transmission development plan 2013-2022

TRANSMISSION DEVELOPMENT PLAN

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Office: Long-term Planning and Development


2013-2022

January 2013


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1. INTRODUCTION ................................................................................................ 5

1.1. Role of the Transmission System and Market Operator ............................................ 7

1.2. Transmission network ............................................................................................... 8

1.3. Access to Planning .................................................................................................. 10

1.4. Content of the Plan ................................................................................................. 12 2. GRID CODE TECHNICAL REQUIREMENTS .............................................. 13

2.1. Introduction ............................................................................................................ 13

2.2. Relevant data for planning –requirements for the transmission system users ........... 14

2.3. Data Attributes ....................................................................................................... 14

2.4. Standards and criteria for transmission network planning ........................................ 15

2.5. 400 kV, 220 kV and 110 kV Network Planning Criteria .......................................... 16

2.6. Long-term planning criteria for the revitalizing of the transmission network ........... 19

2.7. Planning methodology ............................................................................................ 21

2.8. Substation configuration planning ........................................................................... 22

3. ELECTRICITY LOAD FORECAST ..................................................................... 26

3.1. Introduction ............................................................................................................ 26

3.2. Background history of the load, and current situation ............................................. 26

3.3. Demand profile ....................................................................................................... 27

3.4. Long term forecasts of demand 2013-2022 ............................................................. 31 4. GENERATION CAPACITIES OF KOSOVO POWER SYSTEM .................... 32

4.1. Introduction ............................................................................................................ 32

4.2. Planning of the new generating units ....................................................................... 34

4.3. Renewable sources .................................................................................................. 35

4.4. Application for connection of the HPP “Lumi Deçani” with the transmission grid . 36 5. KOSOVO TRANSMISSION NETWORK DEVELOPMENT PROJECTS ..... 37

5.1. History of the transmission network ....................................................................... 37

5.2. Implemented projects 2007-2012 ............................................................................ 39

5.3. Transmission network infrastructure development; 2013-2022 ................................ 41

5.3.1. Introduction ............................................................................................................ 41

5.3.2. Ongoing development projects ............................................................................... 42

5.3.3. List of new development projects planned for the period 2013-2022 ...................... 43

5.3.3.1.The list of new projects in the category of transmission network reinforcement...... 43

5.3.3.2. List of new projects, to support the load ................................................................ 46

5.3.3.3. Projects planned for the category of revitalization of KOSTT substations ............. 47

5.3.3.4. Projects planned in the category of supporting transmission system operation ....... 48

5.4. Technical description of projects planned in transmission ....................................... 49

5.4.2. Transmission grid strengthening projects ................................................................ 50

5.4.3. 110 kV line revitalization projects ............................................................................ 63

5.4.4. Load support projects ............................................................................................. 69

5.4.5. Substation Revitalization Projects ............................................................................ 79


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5.4.6. Projects to enhance monitoring, control and measurement systems in the

Transmission System .......................................................................................................... 84 5.5. Rationale for changes in projects of the TDP 2013-2022 in comparison to the TDP

2012-2021 .......................................................................................................................... 88

6. TRANSMISSION NETWORK PERFORMANCE ANALYSIS ..................... 91

6.1. Description of the network model. .......................................................................... 91

6.1.1. Transformation capacities; Q4-2012 ........................................................................ 92

6.1.2. The current load exchange capacity with neighboring countries .............................. 93

6.2. Analysis of the transmission network condition as per topology Q4-2012 ............... 96

6.2.1. N-security criterion analysis ..................................................................................... 96

6.2.2. N – 1 security criteria analysis ................................................................................. 97

6.2.3. Voltage profile and losses ........................................................................................ 99

6.3. Analysis of the transmission network condition by topology- 2018 ....................... 104

6.3.1. N-security criterion analysis ................................................................................... 104

6.3.2. N-1 security criterion analysis ................................................................................ 105

6.3.3. Voltage profile and losses ...................................................................................... 106

6.4. Analysis of the transmission network condition, topology - 2022 .......................... 112

6.4.1. N security criterion analysis ................................................................................... 112

6.4.2. N-1 security criterion analysis ................................................................................ 113

6.4.3. Voltage profile and losses ...................................................................................... 114

6.5. General conclusion ............................................................................................... 120

6.5.1. Network capacity development ............................................................................. 121

6.5.2. N-1 security criterion ............................................................................................ 122

6.5.3. Quality of supply and efficiency ............................................................................ 123

7. FAULT CURRENTS IN THE TRANSMISSION NETWORK................... 124

7.1. Introduction .......................................................................................................... 124

7.2. Calculation of fault currents level .......................................................................... 124

7.2.1. Mathematical model, calculation methodology and applied software ..................... 124

7.2.2. Features of the power circuits of the transmission network ................................... 126

7.2.3. Results of the calculated fault currents .................................................................. 126 7.2.4. Assessments of the calculated fault currents in busbars 400 kV, 220 kV and 110 kV

(2012) ...............................................................................................................................127

7.2.5. Assessments of the calculated fault currents in busbars 35 kV and 10 kV .............. 128

7.2.6. Assessments of the calculated fault currents (2018) ............................................... 130

7.2.7. Assessments of the calculated fault currents (2022) ............................................... 131

8. ENVIRONMENTAL IMPACTS ..................................................................... 132

8.1. Environmental protection ..................................................................................... 132

8.2. Environmental problems in the transmission system ............................................. 133

8.2.1. Environmental problems caused by the lines ......................................................... 133

8.2.2. Environmental problems caused by the substations .............................................. 134

8.2.3. Caution on the other environmental impacts ......................................................... 135

8.3. Environmental plans ............................................................................................. 136 REFERENCES .......................................................................................................... 137


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Abbreviations

ENTSO/E – (European Network of Transmission System Operators for Electricity)

ESTAP I &II - (Energy Sector Technical Assistance Project)

IPA ( Instrument for Pre-Accession)

KOSTT – System, transmission and market operator JSC

KEK – Kosovo Energy Corporation J. S. C.

MZHE – Ministry of Economic Development

MTI – Ministry of Trade and Industry

OPGW – Optical Ground Wire

TSO – Transmission system operator

PSS/E- Power System Simulator/Engineering

TDP – Transmission Development Plan

EES –Power system

SCADA/EMS – Supervisory Control and Data Acquisition/Energy Management System

SECI – South East Cooperative Initiative (Regional transmission planning project)

EMS – Environment management system

TACSR/ACS – (Special conductor with high level of thermal resistance, Al-Çe)

IT – Information technology

ERO – Energy Regulatory Office


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1. INTRODUCTION

Electricity sector as one of the most important industrial sectors in the economy of Kosovo

should be developed and planned appropriately. Transmission network, which is operated by

KOSTT, plays an important role in the energy and electricity system enabling the

transmission of power from generators to large customers and distribution nodes.

The vision of KOSTT is to “to provide safe and reliable service to users of the transmission

system, responsive to social and environmental aspects, integrated to European transmission

mechanisms, while also being financially stable and profitable”.

KOSTT mission is to provide:

- Quality services by implementing technical and technological achievements in the

development of the transmission system;

- Transparency and non-discrimination for transmission system users in competitive

electricity market;

Advancement of the company’s position on the international level through

increased activities in this way.

Related to the above-mentioned responsibilities on the transmission system development

and legal obligations, KOSTT hereby drafts the Transmission Development Plan (TDP),

which represents one of the main foundations of development planning of KOSTT. The

importance of preparing and implementing such document is faced also in the legislative

requirements related to the preparation and treatment of this document and as such belong

to the primary and secondary level legislation.

Legal Requirements: Law on Energy:

- TSO and DSO prepare and publish development plans, in accordance with the requirements of the

Law on Energy Regulator. These plans must be compatible with license requirements and the

Energy Strategy, Strategy Implementation Plan, and Energy Balances.


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Law on Electricity:

- TSO shall be responsible for fulfilling requirements related to the ten (10) year system development

plan, as per sub-paragraph 5. 6 of paragraph 5 and paragraph 6 of Article 14, Law on Energy

Regulator.

Law on Energy Regulator:

- The Energy Regulatory Office shall examine whether the ten-year development plan submitted by the

transmission system operator covers all investment needs identified in the consultation process, and

may require the transmission system operator to amend the ten-year system development plan as

appropriate.

Licenses for the Transmission System Operator:

- In accordance with Article 7 of the Law on Energy and article 12 of the Law on Electricity, and

Article 14 of the Law on the Energy Regulator, the Licensee shall develop and publish a medium

(3-5 years) investment development plan that shall derive from long-term transmission system

development plan (10 years). Such a development plan shall be made in conformity with the

applicable legislation by consulting current and potential system users. Before its, publication, the

plan shall be submitted to ERO for approval

Grid Code:

- Each year TSO will prepare and issue a detailed plan on Transmission Development Plan

(TDP) for the next 10 years.

Rule on licensing energy activities in Kosovo:

- Transmission System Operator license applicant, in addition to the requirements of Article 9 and

10 of this rule, shall submit to ERO the system development plan, as defined in Article 12,

paragraph 1 (1. 20) of the Law on Electricity, and Article 7 of the Law on Energy, including the

system development’s impact in the tariffs approved by ERO.


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ENTSO-E Requirements: According to the article of the (EC) Regulation No. 714/2009 of the 3rd package that

defines the coordination of the operation and development of the transmission system "an

extensive network plan for the community-wide should include modeling of integrated

network, scenario development, an adequacy concept generation and an assessment of the

resilience of the system”. Furthermore, TDP (Transmission Development Plan) should

“build on national investment plans and, if appropriate under the guidelines for energy

networks”.

Pursuant on the above mentioned legal obligations, KOSTT is obliged to draft and after

approval from Energy Regulatory Office, to publish and implement such document,

which is drafted in full compliance with Energy Strategy of Kosovo.

1.1. Role of the Transmission System and Market Operator

KOSTT mandate is defined by the Law on Electricity, secondary legislation and licenses

issued by the Energy Regulatory Office (ERO). KOSTT as an independent operator of

transmission system and market is responsible for operating and developing the transmission

system, including network transmission and operation of electricity market.

KOSTT responsibilities related to the transmission network development are:

- Organization of preliminary studies for possibilities for new constructions of transmission capacities,

facilities and equipment, supported by technical, economic and financial studies

- Compilation and publication of short and long term plans for expansion and modernization of the

transmission network.

- The development of transmission network and interconnection with neighboring networks in order to

guarantee the security of supply,

- Provision of sufficient information on any other system operator to which the system is connected to

ensure that it is a matter related to their development requirements

- Coordination on the planning and development of transmission network with counterpart companies

in the region and drafting of the ten-years plan at the ENTSO-E level


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Under the granted license, KOSTT shall prepare and publish the mid-term (3-5 years)

transmission development plan as part of the ten-year development plan. After its

approval by the Energy Regulatory Office, TDP should be published by KOSTT.

Network users can use this Plan to plan their future activities, for new connections or

strengthening the existing ones.

1.2. Transmission network

Kosovo Power System, is interconnected through cross border lines with the neighboring

countries: Serbia, Macedonia, Montenegro and Albania through high carrying capacity lines

400 kV, 220 kV and three 110 kV lines. Kosovo Power System is characterized by strong

network interconnection voltage of 400 kV, which is strongly interconnected in the regional

network. Powerful interconnection of the transmission network with the surrounding

networks the ranks the Power System of Kosovo, as one of the important nodes of Power

in the region and beyond. The continuous increase of electricity consumption in the country

and the region, increase power flows in the internal lines and those of interconnection. This

increase of power flows continuously narrows safety margins of the stability of Kosovo’s

Power System, and other systems interrelated with our system. Necessary reinforcements in

the transmission network in the country and in the region are vital in maintaining the

stability and reliability of the system in the near future.

After the decision of the Government of the Republic of Kosovo (no. 10/29 2011) on the

transfer of a part of the 110/35 kV grid and 110/10(20) kV grid from the DSO to the

KOSTT, the transmission system is operating at five voltage levels, 400 kV, 220 kV, 110 kV,

35 kV and 10(20) kV. The boundary of assets with generation and eligible consumers has

remained the same, while the boundary with the Distribution grid has been displaced from

the borns 110 kV of load transformers in connection points at busbars 35 kV and 10 kV at

the bottom of transformer fields 35 kV and 10 kV. This includes the system of auxiliary

supplies, together with the transformer fields for own-consumption at substations 110/35

kV, 110/35/10(20) kV and 110/10(20) kV, and the command facility and the areas around

the location. The figure 1-1 shows the technical boundaries after the Government decision.


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Figure 1-1. Technical boundary between KOSTT and parties connected to the transmission grid

The main problems identified in the assets transferred are mainly related to the transformer

fields 35 kV, with an outdoor construction, built in the 70es and 80es. Also, we have

identified equipment which are not dimensioned according to the short connection load of

the substation in which they were built in. Four 110/10 kV substations have only one

transformer each, the operations of which do not ensure required reliability in consumer

supply, and render the maintenance process rather difficult, due to the lack of alternative

supply lines.

In this TDP, the list of projects from the previous plan was updated in terms of temporal

implementation, and detailed analysis were undertaken, based on the asset transfer from the

KEK-DSO to KOSTT, and emergency and long-term consolidation requirements were

identified, for the part of the grid transferred to the KOSTT management. Preliminarily, a

Transmission network

400kV, 220kV dhe 110kV

KOSTT

G

220kV,110kV

10(20)kV

400kV,220kV,110kV

Generation

10(20)kV

35kV

DSO

220kV, 110kV

6.3kV,10kV,35kV

Industrial consumers

AC/DC

AC/DC

10(20)kV

35kV


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detailed survey of transferred equipment was undertaken by the Planning and Maintenance

Engineers, with a view of identifying the technical condition of load transformers, their

fields, and other auxiliary equipment (protection, control).

1.3. Access to Planning

The process of planning and development of transmission network is a long and complex

process. The process involves a number of activities, such as network development in

relation to energy demand prediction, generation prediction, enabling the identification of

necessary reinforcements and extensions needed to achieve network operating within the

parameters of reliability and environmental impact. Although TDP takes as a reference the

prediction for a certain period based on the Long-Term Energy Balance, the plan must also

convey the strategic development of the transmission system over the long term timeframe.

The planning process is a result of the process of restructuring the energy market. The

planning process has changed in some respects, compared to the previous process in the

vertically integrated companies:

- Uncertainties coming from the market environment and input data.

- Objectives of different network users (generators, traders, suppliers, customers and network

operators)

- Incompliance and disproportion between the technical, economic, environmental and social

requirements.

- Uncertainties coming from the level of integration of energy from the renewable sources

In addition, the need for regional market integration requires increasing and strengthening of

the interconnection capacity, which affects the planning process at national level. Network

development options based on the Planning Code and on the general planning rules

recommended by the ENTSO/E. Determinative methodology (defining), which is based

on the security criteria N-1, presents the basic methodology applied in this plan, the purpose

of identifying and determining the list of projects necessary for development of the

transmission network.


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This plan contains information on the development and reinforcement expected to occur in

the transmission network in Kosovo for 10 years in the following:

- Building of new transformation and transmission capacities,

- Strengthening of existing transmission and transformation capacities,

- Construction of the interconnection lines with the neighboring countries,

- Revitalizing of the existing equipments of the high voltage (lines and substations)

- Development of supporting systems of transmission system.

It also contains information on the possibilities of connecting new generating units and new

loads in the transmission system.

The main objective of the ten-year plan is to identify projects which will increase capacity,

reliability and efficiency of the operation of the transmission network. This plan will enable

consumers, energy market participants, energy producers, prospective investors to familiarize

with the transmission development plan for the next ten years.

This document presents development plan drafted in KOSTT, covering a ten year period,

from 2013 until 2022, in compliance with the ENTSO/E requirements, where the year

2012 represents the reference year, or the so-called year zero. All information in the

development plan, such as project details, the expected starting date of the project

implementation, network transmission connection applications in in 2011, and those

ongoing until end 2012, are all taken into consideration in developing this document.

For the preparation of development plan appropriate calculations were made with the

relevant software PSS/E 33, simulating computer models of the system based on data

provided by KOSTT and network users, and based as well on the load prediction for the

next 10 years. Load forecast is based on historical data (consumption, maximum load, the

load duration curve, etc.), as well as the expected demand from industrial and commercial

consumption and new connections expected to occur. Generation data are provided by

KEK - Generation and other generators. Data for interconnections expected to be built in

the region, were provided by studies made in the Planning Group for Regional Transmission


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Network Planning - SECI, in which group KOSTT contributes as well through its

representatives

For each year of development, studies were conducted for the power flows, simultaneously

following the increase of the demand for maximum load. Calculations were also made for

breakdowns in different periods. Based on results of calculations, it is possible to provide

estimates on how the network will operate for the estimated next years. Bottlenecks have

been identified and possible solutions were presented by analyzing their impact on

improving the operating performance of the transmission network. The transmission

network was analyzed also for minimal loads, thereby identifying eventual problems in

overloads in 400 kV, 220 kV, 110 kV, 35 kV and 10 kV, which may appear in summer

minimal load regimes.

KOSTT has been carefully evaluating the accuracy of information, which does not fall under

KOSTT responsibility, making clear that KOSTT is not responsible for information or

incorrect data received from other parties.

1.4. Content of the Plan

TDP is structured in 8 chapters including the introduction:

Chapter 1– Introduction

Chapter 2 - Technical requirements of the Grid Code - presents the process of data

collection, planning criteria and standards, and configuration of substations by voltage level

400 kV, 220 kV and 110 kV.

Chapter 3 - Presents the electricity demand forecast, broken down in the consumption of

the past three years and forecasted consumption for the next 10 years.

Chapter 4 - List of existing generators and planned ones. It is also presents the renewable

generation and KOSTT policies in support of this technology.

Chapter 5 - Describes the KOSTT network transmission, and interconnection with its

neighbors. A part of this chapter describes in details the future developments of the

network.


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Chapter 6 - System performance is presented for different network conditions for certain

periods of development plan.

Chapter 7 – Contains the results of the short circuit currents for certain periods of time, in

order to assess the disconnection ability of existing circuit breakers and the dynamic stability

of high voltage equipment in case of occurrence of failures in the transmission network.

Chapter 8 - Includes access to environmental planning policy in relation to the

Transmission Development Plan

Chapter 9 - Contains a list of references.

2. GRID CODE TECHNICAL REQUIREMENTS

2.1. Introduction

One of the main KOSTT objectives is development of the transmission system with the

purpose of safe, efficient and reliable operation in order to enable electricity operation,

fulfilling the demand in compliance with the legal requirements. Transmission System

Operator has planned developments of the network based on long-term electricity needs.

Demand for electricity transmission depends on many factors: increased consumption,

installation of new generating units, new cross-border lines, development of heavy industry,

etc.

The need for reinforcements in the transmission network is determined based on the study

of network performance against the planned technical standards outlined in the Grid Code

respectively Planning Code.

The Grid Code covers the operational procedures and provisions governing the interaction

between KOSTT and users of the Transmission System in Kosovo. This code also includes

the processes of planning, connection, operation and balances system in normal and

emergency situations. Processes include different periods based on the situations in the past,

current situation and long-term domain.

The Planning Code specifies technical criteria and procedures to be applied by KOSTT in

planning and development of the Transmission System of Kosovo. Even users of the

Transmission System during the planning and development of their systems should consider

the Planning Code. This code also sets requirements for the collection of reliable


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information from users, so that KOSTT can make planning and development of

transmission system in Kosovo.

Based on Article 15 of the 'License of the Transmission System Operator' Transmission

System Operator also has developed the basic planning criteria which are detailed in the

document approved by the ERO, "Transmission System Security and Planning Standards ”.

This document defines a range of criteria and methodologies that KOSTT should adopt

(enforce) in the planning process of developing the transmission network in Kosovo

2.2. Relevant data for planning –requirements for the transmission system users

In order for KOSTT to implement its Transmission Network development plan, all network

users are required to submit relevant data affecting the determination of the plan. This

section will briefly describe the process of collecting data needed for long-term planning,

since more detailed ones can be found in Planning Code - Grid Code, which can be

downloaded from the official site of KOSTT: www. kostt. com

During the process of applying for new connections to the transmission network, to enable

the completion of each connection offer - each user must submit to KOSTT the standard

data of planning and preliminary project planning, attached to the application for connection

application, and within two months from the date of the receiving the bid, the detailed

planning data should be submitted. Any change from the previous data network users, the

party is obliged to inform KOSTT in order to revise data.

KOSTT is also required to present users with the system data to enable users to model their

network related to the contribution of the fault currents.

2.3. Data Attributes

The data, which transmission system users are obliged to send to KOSTT, are characterized

depending on the type of system users. They usually fall into two main categories:

- Generator, and

- Load.

http://www.kostt.com/


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Existing and new generators are required to submit data for generating units’ plants, which

are required by KOSTT, and all data changes that occur for different reasons. Each

generation in the application for connection to KOSTT for getting a new connection or

modification of an existing connection, must provide the necessary information as required

by Planning Code.

The data which are filled must contain the information such as plant location, name and type

of facility, estimated date of commission etc. , and information of the technical nature such

as expected monthly production of power, features of the power generator, the technical

characteristics of synchronous machine, turbine, adjustment equipment (speed regulator,

exciter, fluctuations stabilizers), the data of step-up transformer, the connection

configuration, data allocation and the type of relay protection, data for the own consumption

needs of the plant, etc. .

The load has the character of distribution points that use the transmission network. They

represent all the substations and distribution network, the network included 220 kV and 110

kV , and industrial customers connected to the transmission network.

Each user with the loading application for connection submitted to KOSTT for a new

connection or modification of an existing connection must provide the necessary

information as required by Planning Code. This information should contain information

about the substation location, time of becoming operational, load forecasting for the next 10

years, etc, and technical data such as configuration of the substation, voltage level,

transformers data, data on high voltage equipment, nature of the load, type of obstacles in

low voltage level, etc.

Detailed description about the user data at this point is made so that the reader could have a

clear perception that any inconsistence in this document is subject to the user if they follow

the criteria listed above.

2.4. Standards and criteria for transmission network planning

Transmission network planning is based on the criteria set out in Planning Code, which are

described in detail in the document “Transmission System Security and Planning Standards”.


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Standard method of planning or determinative methods of transmission network planning,

which presents the classical method used in many countries, which also applies to KOSTT.

The main principle according to which the transmission network is dimensioned, is the

necessity of fulfilling all technical requirements in accordance with Grid Code, and that the

N-1 elements at work facing the most difficult conditions for operation. So basically this

method of planning is mainly based on critical conditions of operation of the transmission

network. In principle, planning the transmission system in Kosovo is conduct is such a

manner that the operation of the system meets the criteria 'N-1'. However, in some

situations where it is not efficient to fulfill the 'N-1' criteria there will be applied exemptions

for a period of time.

In relation to substations 110/35 kV and 110/10(20) kV, and those combined

110/35/10(20) kV, fulfillment of the N-1 criterion is a complex process, depending on the

medium-voltage network infrastructure, which is managed by the DSO. The N-1 criterion is

not met in a large number of substations, in terms of transformation, but in substations with

two or more transformers installed, even despite the failure to fulfill the N-1 criterion, in

coordination with the DSO, this criterion may be achieved, if the connection reserves of

medium voltage grid are used. This implies the transfer of lost load from the failure of one

transformer to the other transformer, or to the other substation, by connecting switches,

which are mainly open and enter into operation in such cases. One of the most complex and

costly cases in fulfilling the N-1 criterion is when the substation has two medium-voltage

levels, 35 kV and 10(20) kV. The N-1 criterion can be accomplished at a much lower cost if

in the side of the distribution system, reserve modular substations 35/10 (kV) are installed,

which would serve only in cases for load transfer from 35 kV to 10 kV, or vice-versa. This

can be achieved by harmonizing the two development plans of the KOSTT and DSO,

thereby minimizing the investment cost.

2.5. 400 kV, 220 kV and 110 kV Network Planning Criteria

Kosovo's transmission system in the 400 kV and 220 kV levels has technical and economic

characteristics which differ from the 110 kV systems. Investment cost and their

dimensioning criteria are much higher than at 110 kV. Transmission system is


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interconnected with regional transmission systems through the network of 400 kV and 220

kV, so the effects of investment in network voltage 400 kV and 220 kV are not isolated but

have a regional character. KOSTT has defined the strategy for developing the transmission

network which is oriented in strengthening/development of the network 400 kV and 110

kV, whilst network 220 kV will not be develop further, except for specific cases where no

other solution could be found.

Transmission System Planning is made according to the criteria defined by the Grid Code,

considering the fulfillment of the N-1 criteria, meaning that the system must be capable of

normal operation in case of occurrence of the fault in the network (in Kosovo or in other

systems) and the loss of one of the following elements:

- airline or cable lines

- transformer,

- compensator, and

- generator (this criterion cannot be seen in the plan, but it is a requirement for the developers of

generation capacity)

In case of loss of one of the above elements as a result of failures or maintenance,

transmission system must fulfill the following operation conditions:

- transmission lines should not be loaded above their thermal limits,

- reduction of the supply capacity is not allowed

- level of voltage tension and speed change cannot exceed allowed limits,

- transient and dynamic stability of the Power System should not be endangered, and

- power transformers should not be over-loaded.

The 110 kV network, which development is done in accordance with the Transmission

Connection Tariff Methodology of KOSTT, includes all equipment, voltage 110 kV (lines

and facilities) in addition to the distribution transformers 110/10 (20) kV and 110/35 kV

and relevant transformation fields, now transferred from KEK DSO to KOSTT.

In normal operating conditions the performance of the transmission system should be

operating in accordance with criteria outlined in the Grid Code.


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Grid Code defines the allowed voltage limits in the transmission system as in Table 2. 1

Table 2-1 Allowed voltage limits

*Allowed limits of medium voltage are referenced in the Distribution Code

Loading the transmission lines above the designed thermal limits of the conductors, will be

perceived as overload of the line. Also, each load of the transformer above their nominal

power will be considered as their overloading.

The following table shows thermal margins for conductor of the cross sections, which

standards are applied in KOSTT.

Table 2-2 Standard electrical parameters for air lines and cables


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High voltage facilities operating in the transmission network should be durable and

sufficiently safe in case of failures of the system. The Electrical Equipment Code defines

maximal nominal currents, maximal fault currents and allowed duration of faults. Table 2-3

shows nominal currents for high and medium voltage equipment.

Table 2-3 Standard electrical parameters for disconnection equipment

2.6. Long-term planning criteria for the revitalizing of the transmission network

The revitalizing plan for the electro-energetic elements as overhead lines, transformers,

cables and substations, generally depends on the technical situation, their age and intensity of

use of these elements in retrospect. The revitalization plan of the transmission network

equipment is done as follows:

- Overhead lines: their revitalization depends on two factors: their age and level of losses

incurred in the line during a long – term period. For phase conductor and earth wire,

insulator, connection bridges, the time of 40 years represents a condition for adding them

into the revitalization list. Frequency of breakdowns in lines is an additional indicator to

select the revitalization list.

Nominal Voltage

Maximal

operation

current

Fault

current

Fault

dynamic current

Fault

permitted

current

400 kV 2500* A 40 kA 100 kA 1 s **

220 kV 2500 A 40 kA 100 kA 1 s **

110 kV 2000 A 40 kA 100 kA 1 s **

35 kV 1600 A 25 kA 63 kA 1 s **

10 (20) kV 2500 A 25 kA 63 kA 1 s **

10 kV*** 3150 A 40 kA 100 kA 1 s **

6. 3 kV 3150 A 40 kA 100 kA 1 s **

* In specific cases and conditions, the 3150 A current may be adapted ** In specific cases and conditions, the 3s time current may be adapted ***In specific cases when used for 63 MVA transformers, 110/10 kV and when Parallel works of the transformers in the 10 kV side is envisaged


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In terms of losses in the list for revitalization are included the lines of cross section of

150mm2, which are also associated with the first factor, since the initial development phase

of the transmission network (1950-1970) 110 kV lines are built with the cross section

conductor of 150mm2. This development concept is now being applied in all ENTSO/E

transmission systems. 220 kV lines are considered to be older lines (>50-60 years), since

their development took place mainly during the 60-ies and 70-ies. The European concept

consists on the point that 220 kV lines are gradually re-raised to 400 kV level, mainly using

only their routes. The difficulties faced in expropriation of private properties for

development of new lines are distinct in all countries in Europe.

- Power transformers: plan of replacing the power transformers of the transmission

network is based on their expected lifetime, which is estimated at 50 years. Another

important factor which affects that the transformers will be included in the list for the

replacement is their factual situation, which is monitored by maintenance teams through

their periodic testing. Historical statistical data of events in specific transformers (load level,

number and frequency of measures in protecting transformers, gas analysis, etc. ) are an

important factor in selecting new transformers to replace the old ones.

Selection of nominal power of transformers will be standardized: For the level of 400/220

kV voltages 400MVA automatic transformers are recommended, for the level 400/110 kV

300 MVA automatic transformers are recommended, for the 220/110 kV voltage level,

150MVA automatic transformers, while for 220/35/10(20) kV, 110/35/10(20) kV levels, it

is transformers with 40 MVA and 31. 5 MVA power. For specific cases, such as large

industrial consumption, transformers with a higher power than 40 MVA can be adapted.

- Substations (overhead line bay and transformers): the revitalizing plan of the

substations areas, which are included in the defined boundaries of the transmission network,

is also based on age of the equipment and their factual situation. Priority for revitalizing have

substations with high impact on transmission systems, but also all the substations that their

age has passed 40 years. Systematic transition from oil-containing disconnection equipment

to gas equipment SF6 is an objective of KOSTT, provided by development and investment


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plans. After the relocation of the boundary between KOSTT and DSO in the medium

voltage level, priorities in Revitalization projects have been revised, resulting with a change

of priorities in some projects presented in the previous year’s plan.

2.7. Planning methodology

The approach of the transmission network planning methodology consists of the following

steps:

- Collection of input data (creation of data base for computer modeling of the network).

- Definition of different scenarios taking into account factors strengthening the development of

generation, load, applications for connection, balance of power system, exchanges etc.

- The creation of computer models of the network transmission format to PSS/E.

- Determine the plan for revitalizing the existing electrical equipment on the basis of their life cycle.

- Identification of network constraints (N-1 tests).

- Definition of the possibilities of strengthening the network on the basis of N-1 tests.

- Analysis of the voltage profiles and losses in the system.

- The final definition of the reinforcement plan and plan for revitalizing transmission network

Figure 2-1shows the transmission network planning methodology


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Figure 2-1 Transmission network process development and revitalization planning

2.8. Substation configuration planning

KOSTT has prepared a document on the Transmission System Security and Planning

Standards, which sets forth planning standards for substations 400/220 kV, 400/110 kV,

220/110 kV and 110/10 (20) kV, a document which is approved by ERO.

All 400/110 kV substations planned will be configured with double bus bars with coupler

and open system. Dimensioning of electrical equipment shall be based on the Electrical

Equipment Code, always being supported by computer analysis of power that define the

power flows and short circuit level to the respective substations. These criteria may

exempt those substations to which power generators and consumers of such importance

Gathering of input data and Creation of system model in PSS/E

Creation of models with current and Planned conditions

Technical analysis of the performance of

system ( Power flows , criteria N -1 with PSS/E

Identification of needs for system reinforcement

Creation of different scenarios of system reinforcement

Selection of most optimal scenarios and

Creation of final list of development

Projects and revitalization of the TN

Technical analysis of the performance of system (power flows, criteria N-1)

with PSS/E

Evaluation of applications for connection to TN

Connection approved

Revitalization plan of transmission network

Data on the state and ageing of equipments


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can be connected, so as to require a higher operational security level in a link. In these

cases the design of bus bars can take into account additional specifications.

Figure 2-2 presents a standard configuration for substations of 400/110 kV voltage level.

Double bus bars system for 400 kV voltage level shown in figure 2-2 can be advanced

with the additional system of the auxiliary bus bars in substations that are connected to

more than three 400 kV lines.

Figure 2-2 Standard planning of the bus bars configuration of new substations in the transmission

network

220/110 kV substations’ configuration will be similar to the 400/110 kV substations.

Configuration of substations 110/10 (20) kV is designed based on two criteria regarding

system bus bars of 110 kV. Determining criteria in determination the busbar system


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configuration will be number of lines planned to be connected in the 110 kV substations.

For substations that will be connected in the long term only with two lines, “H” type bus bar

system applies, as shown in figure 2-3. Medium voltage busbar system 35 kV and 10(20) kV

are also designed with the dual busbar system with a connecting field. Technical concept of

the construction of 35 kV transformer fields could be with outer construction (AIS), or with

internal modular construction installed within the commanding facility. The latter is more

preferred given the savings in space. 10(20) kV transformer fields are planned to be modular,

installed within the commanding facility. In addition, own consumption field, which after

displacement of the technical boundary with DSO belongs to KOSTT, should of the same

type.

Figure 2-3

Substations that will be connected with more than two lines, the double bus bar system with

couplers applies, as shown in the figure 2-4.


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Figure 2-4

Nominal power of the substation shall be projected based on long-term projections of the

relevant substation load. 110/10(20) kV transformers with nominal power of 2x31. 5 MVA

and 2x40 MVA shall be standardized during the projection of 110/10(20) kV substations,

whereby the space for the third transformer field shall be available to hold the

transformation reserves in case of unplanned load increase.

The dimensions of the phase and protective conductors for transmission lines are also

standardized as follows:

For 110 kV lines: conductor 1x240/40mm2 of ASCR, earth wire C 1x50 mm2;

For 220 kV lines: conductor 1x360/65mm2 of ASCR, earth wire C 2x50 mm2 or

1x490/65 mm2 of ASCR earth wire C 2x70 mm2.

For 400 kV lines: conductor mm2 of ASCR 2x490/65, earth wire Al 2x126 mm2.

There is also another technology and conductors that have been applied in KOSTT. These

conductors called "Hot wire" are the work of special alloy TACSR/ACS, which has the

ability to work at higher temperatures. Usually used for short length of lines and where there

is no possibility of strengthening the pillars. Their transmission capacity, e. g. a conductor of

TACSR/ACS of 150/25mm2 / is the same with the transmission capacity of a conventional

conductor 240/40mm2, while the weight is almost the same as conventional 150/25mm2

conductor. Their handicap is that such replacement of conductors does not help reduce

power losses, and therefore they are preferred only in short circuit lines and those cases

T 1 T 2 Reserve

Tr. Bay

Bus coupler

Line 110 kV

Line 110 kV

Line 110 kV Reserve bay Reserve bay

B 1 B 2

110 kV


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where there is no possibility of reinforcement of the towers, which is not possible to install

because of the weight of the conventional conductor of 240/40mm2.

All the new (and enforced) lines will be equipped with at least 48 OPGW fibers in protective

conductor to support the planned telecommunications network SCADA/ EMS.

3. ELECTRICITY LOAD FORECAST

3.1. Introduction

One of the basic data determining future transmission capacity development is to forecast

electricity load or power. The load forecast represents an integral part of network, generation

and and transmission and distribution system operation planning. The main source of data

for development of load forecast in the next 10 years is the demand forecast model

developed by KOSTT, used by the document: Long-Term Energy Balance 2011 to 2020[2].

This model provides a 10 year forecast, hourly electricity demand. As such, this model allows

forecasting of load for each hour in the next 10 years, including seasonal peak loads (winter

and summer).

3.2. Background history of the load, and current situation

For several years the electricity sector in Kosovo has faced electricity supply problems. Daily

shedding, planned or unplanned are still present. This means that the recorded consumption

is not the same as demand which would exist if there was a safe and quality supply of

electricity. Planned reductions (scheduled) are mainly done in the hours when required

consumption cannot be covered by local generation capacity and lack of imports, or because

of capacity limitation of the DSO. The unplanned reductions happen due to unexpected and

unforeseeable faults, and because of interruptions in generation units, in the transmission

and distribution and network infrastructure.

Figure 3-1 shows a historical chart of development of maximum load for our country. The

unusual nature of the load curve in years reflects the political and economic situation in

Kosovo. After the end of the war in Kosovo (1999) and to date, the maximum load has

marked an average annual growth of 6%.


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Fig. 3-1Peak history over years in Kosovo

The figure 3-1 shows maximum loads registered for years 2002-2011, for winter and summer

seasons. The maximum load for 2011 increased for 0. 5 % compared to the previous year.

Tab. 3-1Maximum active loads, summer and winter, for the period 2002-2011

3.3. Demand profile

Characteristics of the load duration curve of the Power System of Kosovo has undergone

constant changes, both in terms of growth but also proportional to the change of load

factor. In figure 3-2 we can see the load duration curve for the previous year in 2011.

Summer consumption growth has led to increased load factor by 0. 57, while other

characteristics of the load duration curve are as follows

1. 54% of the annual period the load was above 1000 MW, 22% of the year, the load was in

the range between 800MW until 1000 MW.

Pe

ak [M

W]

Year 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011

Winter peak [MW] 723 759 811 898 916 933 967 1072 1156 1150

Summer peak [MW] 560 597 569 617 637 690 764 795 810 804


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Fig. 3-2Curve of the duration of the load for 2011

The electricity demand in Kosovo marks a curve which in a considerable time of the year

(winter season), is not constant as a result of reduced consumption in times of peak loads.

Such a curve may be seen in the figure 3-3, which provides a weekly chart in the winter

season, for a typical week of January 2011. Latent consumption provides the real

consumption, if there would not be any consumption reduction. Load shedding causes

deformation of the consumption curves, and as such it differs them from no-shedding

curves, which do not display any obvious surge. Peak loads are marked between 19 and 21

hrs, while the minimum loads between 4 and 6 hrs in the morning.

LOAD DURATION CURVE FOR YEAR 2011

Peak Pmax=1150 MW Load factor LF=0.57

Average Power Paver=642 MW

1.54% of the year, P>1000 MW

22% of the year 800 MW<P<1000 MW


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Fig. 3-3 Typical winter chart in January 2011

Figure 3-4 provides a daily diagram for a characteristic day of January 2011, which

corresponds to one of the reference points as per ENTSO/E. This diagram provides two

curves, from which the first shows consumption made, the second shows the latent

consumption, based on data registered in the dispatch diary of KOSTT. Load shedding in

normal working conditions of the electro-energy system usually occurs in two consumption

ranges: 9:00 – 12:00 and 17:00 – 23:00 hrs. The difference between maximum and minimum

values in winter loads for 2011 is around 450MW or 35% of the peak value.

400

500

600

700

800

900

1000

1100

1200

1300

1 9 17 25 33 41 49 57 65 73 81 89 97 105 113 121 129 137 145 153 161

[MW

]

7 days

Latent consumption Consumption


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Fig. 3-4 Daily load diagram for one selected day in January 2011

Figure 3-5 provides a daily chart for a typical day in July 2011. There is no load shedding in

this chart, and the difference between maximum and minimum values of daily loads is

around 51%. In this time period, this difference in loads makes it very difficult to balance the

system, especially after midnight, when loads are minimal, and fall under the boundaries of

technical minimums of existing plants.

955

10451065

630

915

1015

1035

500

600

700

800

900

1000

1100

1200

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24

Daily Load: Wednesday 3-rd January 2011

Latent consumption realized consumption

Load shedding

MW


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Fig. 3-5 Daily load chart for a typical day in July 2011

3.4. Long term forecasts of demand 2013-2022

The power and load forecast is based on the forecast provided by the document: “Long-

Term electricity Demand 2013-2022”.

For forecasting power and load demands in Kosovo, a complex mathematic model was

created in Excel, which links the influence of four variables (correction factors) in calculating

power and electricity demands. The above-mentioned factors are presented in the following:

- Factor 1: Implementation of the Government program for efficient electricity use;

- Factor 2: Reduction of consumption due to a more efficient billing, and more effective metering and

checking procedures (reduction of commercial losses);

- Factor 3: Influence of GDP forecast in consumption development;

- Factor 4: Forecasting technical losses in transmission and distribution networks

The forecast of demand development for power in the period 2013-2022 according to three

scenarios of growth is presented by figure 3-6, while numerical data corresponding with

figure 3-6 are presented in the table 3-2.


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The basic scenario of load development is characterized by an average annual growth of 2.

41%. This load development scenario shall be the main input in assessing operational

performance of the transmission network.

Figure 3-6 . Low, basic (average) and high growth scenarios for peak loads (maximum load)

Table. 3-2. Respective data of peak forecast, related to Figure 3-6

4. GENERATION CAPACITIES OF KOSOVO POWER SYSTEM

4.1. Introduction

Electricity in Kosovo is produced by two relatively large power plants: PP Kosovo A and

Kosovo B. Both power plants use coal - lignite as fuel. Pursuant to the Government Energy

Program, it has been foreseen that in the period between 2016-2017, capital overhauls will be

1584

1072

1158 11501170

12201250

12831310

13401365

13901410

1452 1494

1404

1000

1050

1100

1150

1200

1250

1300

1350

1400

1450

1500

1550

1600

1650

2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022

High scenario Base scenario Low scenarioMW


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performed on B1 and B2 units, which is to reflect on reliability of operation of these two

units. Units A3, A4 and A5 of the TPP Kosova A according to the Energy Strategy 2009-

2018, shall be operating until the end of 2017, until they are ultimately decommissioned.

Table 4-1. Main features of Kosovo A and Kosovo B generation units

Apart from Kosovo A and B power plants, managed by KEK, there is also a hydro-power plant Ujmani (2x17. 5MW), managed by the POE Ibër-Lepenci. There are also low capacity hydro-power plants in operation. The table 4-2 provides the key data on small HPP-s connected to the distribution network.

Table 4-2. Main features of existing hydro-power plants of Kosovo

Unit Starting Time Action Lifetime

Kosova A

A3 1970 Regular overhauls 2017

Existing TPP A4 1971 Regular overhauls 2017

A5 1975 Regular overhauls 2017

Kosova B

B1 1983 Capital Revitalization(2016) 2030

B2 1984 Capital Revitalization(2017) 2030

Ujmani

Existing HPP U1+U2 1983 Regular overhauls >2030

Lumbardhi

G1+G2 1983 Planning increasing capacity 2030

EXISTING GENERATION UNITS

*During 2012 and 2013 is expected to install new filters in A3,A4 and A5

Installed Net Disposal HPP UJMANI G1 17.5 16 16 1983 G2 17.5 16 16 1983 HPP LUMBARDHI* G1 4.04 4.00 4.00 1957 (2005) G2 4.04 4.00 4.00 1957 (2005) HPP BURIMI G1 0.34 0.34 0.34 1948(2010) G2 0.136 0.13 0.13 1948(2010) HPP DIKANCE* G1 0.67 0.66 0.66 1957(2010) G2 0.67 0.66 0.66 1957(2010) HPP RADAVC 0.00 G1 0.14 0.14 0.14 1934 G2 0.14 0.14 0.14 1934

* HPP Lumbardhi and HC Dikance are given in private investment concession

GENERATING UNIT Capacity units of HPP [MW] Put on operation


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4.2. Planning of the new generating units

Estimates of new generating units for the period 2013-2022 is designed based on the

expected generation from existing generating units, including the continued operation of

some units of PP Kosovo A until 2017, existing hydro plants and new ones planned to be

built, as well as production from PP "New Kosovo" and HP Zhuri

The new generation capacity development concept is focused on primary energy resources in

Kosovo. This concept presented by the Energy Strategy 2009-2018, and updated in the most

recent data of the MED, forecasts during the 2013-2022 period:

Development of the Kosova e Re Power Plant

Development of the Zhur Hydro-Power Plant

Development of renewable energy generation capacities (small HPPs, wind turbines, biomass-

fueled plants, and solar panels)

The Kosova e Re Power Plant project shall consist of two units at an installed capacity of

2x300MW. The first unit (300MW) is expected to be commissioned by the early 2018, while

the second unit in 2019. The development of the Kosova e Re Power Plant will be necessary

for the security of supply of electricity consumption increasing in Kosovo. The Power Plant

is expected to abide by all environmental requirements as set and mandated by the European

Union, by using advanced technology which is already proven in commercial use. These

technologies should apply modern coal combustion processes, with a view of achieving a

general efficiency rate of 37%-40%. The development of the Kosova e Re Power plant

project was expected to be coordinated in time with the TPP Kosovo A decommissioning

process (2016-2017), and the capital overhaul of the two TPP Kosovo B units (2016-2017),

but due to current delays, such coordination seems unlikely.

With a view of securing uninterrupted supply of sufficient lignite for the new and existing

plants, a new lignite mining area “Sibovc South” has been opened, with reserves estimated at

830 M tonnes, which is sufficient to supply power plants for a long-term period of over 40

years. The mine is already fully operational, with full generation capacities.


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The base scenario forecasts the development of the known project of the accumulation HPP

“Zhuri”, at a capacity of 305MW, and estimated annual energy generation capacity of 398

GWh. This HPP is planned to be commissioned for operation in the early 2017. Completion

of this project is considered to be of high importance for the optimization of the electro-

energy system, thereby influencing the stability and flexibility, and regulatory reserves for the

system.

4.3. Renewable sources

According to the objectives of the European Strategy 20-20-20 Renewable Energy Directive,

by 2020, 20% of the total energy generated shall be by renewable sources, such as wind

plants, hydro-power plants, etc. Kosovo has also set long-term indicative targets related to

the development of renewable sources agreed with the Energy Community. Renewable

energy source potentials in Kosovo are not as large, both in terms of water potential and

wind. Nevertheless, there are certain regions endowed in such potential, and they must be

exploited. The plans for development of renewable energy generation capacities are also

supported and promoted by the MED, namely through the Government Program for Clean

and Efficient Energy. This program sets the indicative goals for amounts of energy to be

generated from renewable sources. The base scenario of development of renewable sources

requires the development of a large number of small HPPs (>16), totaling a capacity of 128.

2 MW, by 2022.

A considerable contribution in the renewable energy generation is left to the wind turbines,

in which case the plan is to install up to 154 MW of wind generation capacity by 2022, at an

estimated average capacity factor of 0. 22. KOSTT has so far received applications by several

private investors for connecting wind energy generation plans to the transmission network

but still no significant developments regard this.

Development of generation plants which would use biomass and urban waste as fuel is

forecasted to happen by 2014, with a progressive development of capacities of up to 10 MW

by 2022. Meanwhile, a slower development is forecasted for solar panel generated electricity,

as a result of the costly technology.


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4.4. Application for connection of the HPP “Lumi Deçani” with the transmission

grid

Based on the application of 19. 09. 2012, received by the company “KELKOS ENERGY”,

in relation to the possibility of connecting the Hydro-Power Plant with a generation capacity

of 35. 5MW to the transmission network, the KOSTT has undertaken a technical analysis, by

determining the optimal configuration of the connection with the transmission network. The

HPP proposed consists of an expansion of capacities of the existing HPP Lumbardhi (8.

3MW, 22GWh annual generation), by creating a series of small HPP-s on the Deçani river.

The applicant is planning the development of three additional HPPs with the following

specifications:

- HPP Deçani, available capacity PA=14. 3 MW, and planned annual generation of 41. 9 GWh.

- HPP Belaja, available capacity PA=8. 1 MW, and planned annual generation of 24. 8 GWh

- HPP Lumbardhi, available capacity PA=4. 8 MW, and planned annual generation of 17 GWh

In due consideration of the existing HPP Lumbardhi, the applicant has requested the

connection of a total hydro-generation capacity of Pg=35. 5 MW (Wg=105. 7 GWh) with

the transmission network. Upon a detailed technical analysis, the connection is to be made

with the 110 kV busbars of the Deçani substation, through a 35 kV line and uploading

transformer 35/110 kV , at a 40 MVA power.

Figure 4- 1 shows the basic configuration of the interconnection of HPP generators

with the connection point at SS Deçani.


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Fig. 4-1 Optimal connection point of the 35. 5MW HPP to the transmission grid

5. KOSOVO TRANSMISSION NETWORK DEVELOPMENT

PROJECTS

5.1. History of the transmission network

Kosovo Transmission Network during the years has been developed in several stages of

expansion, reinforcement and consolidation.

Between 1953 and 1958, the first line of 110 kV was built in Kosovo, Novi Pazar (Serbia)

until Butel (Macedonia), by interconnecting the substations (SS): SS Vallaç, Trepca SS, SS

Vucitrn, SS Kosovo A, SS Prishtina 1 and SS Prishtina 4, SS Ferizaj 1 and SS Sharri. 110 kV

conductor built in the initial development of the network were 110 kV cross section

conductors of 150mm2.

In 1960 the first line of 220 kV was built in Kosovo, SS Krushevci (Serbia) to SS Kosovo A,

which was at that time in the construction phase. From 1962 to 1975 it was constructed (PP)


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Kosovo A with its five units. In 1978 was built the first line of 400 kV in Kosovo connecting

to the SS Nish (Serbia) with SS Skopje (Macedonia) through SS Kosovo B.

In 1981 was built the HP Ujmani connected through 110 kV line with SS Vallaçi.

The second 400 kV line of the interconnection Ribarevina (Montenegro) to SS Kosovo B

was built in 1983, as well as two 400 kV lines connecting TP Kosovo B (1983) with SS

Kosovo B. In the same year it was built the 220 kV lines from SS Kosova B to SS Prizren 2,

through the switch gear Drenas. In the same year was also built the second 220 kV line to

Drenas followed by the double line for the supply of industrial facilities of Feronikeli.

The 220 kV interconnection line from SS Prizren 2 to Hydro power plant (HPP) Fierza

(Albania) was build in 1988; in the same year, the 220 kV double lines from the SS Kosovo B

to SS Prishtina 4 were also build. Also in the mid 70s and 80s the network of 110 kV

undertook visible development, using conductors of the large section of 240mm2. The year

1990 represents the end of investments in transmission network for a period of 10 years

until 2000, which represents a break of 10 years without investing in the development of the

transmission network. This can be seen in figures 5-1 and figure 5-2.

Fig. 5-1 Intensity of investments in lines1980-2012

km 100

1980 1990 2000

400 kV 220 kV 110 kV

2010

20 40 60 80

Year

km 100

1980 1990 2000

400 kV 220 kV 110 kV

Line investments

2010

20 40 60 80


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Fig. 5-2 Intensity of investments in substations 1980-2012

After the war in Kosovo, the condition of the SEE in Kosovo was dire, including in

generation, transmission and distribution. Emergency investments in the SEE begun at this

time, supported by the Kosovo Budget and international donors. Due to great demand, the

transmission network did not follow the rapid consumption growth trend after 2000.

5.2. Implemented projects 2007-2012

After the establishment of KOSTT and to this date, intensive capital investments have been

done in the transmission network to develop and strengthen the transmission network.

Transmission network reinforcements, modernization of supporting systems for System

Operation, have resulted with a notable increase of reliability and security of supply. Table 5-

1 lists projects implemented thus far. The process, from planning until implementation, was

rather challenging, considering the high development dynamics and implementation of such

a high number of projects. The most challenging process was the implementation of projects

in the same time period, taking into account the minimization of undelivered energy as a

result of load shedding to carry out works during the project implementation. This challenge

was successfully realized thanks to the commitment of KOSTT engineers in optimizing the

project implementation process.

Years

Nr SS/ vit

3

1980 1990 2000 2010

2

1

Nr SS/ vit

3

1980 1990 2000

Investments in substations

2010

2

1


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Table 5-1. List of realized projects in KOSTT from 2007 until 2012.

Nr Project name Year

1 Replacement the line conductor 110 kV, L 125, SS Kosova A-SS Vushtrri 1&2 2007

2 Replacement the line conductor 110 kV, L164/3, SS Prizreni 1-SS Prizreni 2 2007

3 Replacement circuit breaker 110 kV, SS Prishtina1 & SS Prishtina2 2008

4 New line 110 kV, SS Prizren 2- SS Rahoveci 2008

5 Replacement the line conductor 110 kV, L126/1 SS Deçan- SS Gjakova 1 2009

6 AT1 at SS Kosova A, 220/110 kV 2009

7 Rehabilitation of SS Kosova A 2009

8 Rehabilitation of SS Prishtina 1 2009

9 Package Project PEJA 3 2009

10 Replacement of relay protection at SS Kosova B & SS Prishtina 4 2009

11 ITSMO Meters (to the borders) 2010

12 Line 212 adaptation as 110kV,SS Kosova A-SS Ferizaj 1 2010

13 New line 110 kV, SS Peja 3-SS Klina,within the package project Peja 3 2010

14 Connection of SS Skenderaj 110/10 kV, with double circuit line 110kV, in connection point Line SS Vallaq -SSPeja 3

2010

15 AT3 at SS Prishtina 4, 220/110 kV 2010

16 Replacement the line conductor 110 kV, L 126/5, SS Peja 1- SS Peja 2 2010

17 Rehabilitation of SS Kosova B 2011

18 Package Project FERIZAJ 2 2011

19 SCADA/EMS 2011

20 Rehabilitation of SS PRIZRENI 2, 220/110kV & AT3=150MVA 2012

21 IT system to support market operation 2012

22 Replacement of relay protection at SS Prishtina 2 & SS Prishtina 3 2012

23 Circuit breaker 400 kV for generation bay at SS Kosova B 2012

24 Busbar seperation into two sections at SS Gjilani 1 & SS Theranda 2012

25 Rehabilitation of equipment for own supply at SS Kosova B 2012

26 General rehabilitation equipment 110 kV at SS Prishtina 3 (system GIS) 2012


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5.3. Transmission network infrastructure development 2013-2022

5.3.1. Introduction

This chapter presents and examines the development projects of the transmission network

in the period 2013-2022. Considering the planning process of the transmission network as an

extremely complex process, with greater dependence on many factors, the ten-year domain

that defines this document is divided into two periods: first five years 2013-2017 and the

second period of five years, 2018– 2022.

The first period of five years is considered relevant and influential in the long term

development of the network and with high probability of implementation and as such the

projects that are included in this period of time are analyzed in detail. Second period of

2018-2022 includes optional projects in a comprehensive manner that have internal or

regional character for which KOSTT considers their importance and their contribution in

achieving the technical standards for operation of the transmission system in order to

support the electricity market.

Transmission network development projects are divided into four categories:

- Transmission network reinforcements

- New 110/10(20) kV nodes

- Rehabilitation of the transmission network

- Supporting projects of the transmission system (management, monitoring, measurement and control).

Because of considerable complex dependence on the various factors for the implementation

of the projects, the time and manner of such implementation can be considered as subject to

possible changes and as such the next document will revise the data and update them.

Tables contain the project identification codes (ID), a general description of the project, the

expected completion time and reasons and effects of project implementation.


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5.3.2. Ongoing development projects

The investment intensity in the transmission system infrastructure continued throughout

2011-2012, pursuing objectives and aims deriving from the long-term development plan of

KOSTT. Table 5-2 shows projects in implementation during 2012, or which are in the

tendering process.

Tab. 5-2 Projects in implementation, and projects being procured

Nr Project name Technical description Year

1 Transformer 40 MVA,110/10(20) MVA

New power transformer 40 MVA, 110/10(20) kV, in case of emergency

2012

2 Rehabilitation of equipment for own supply at SS Kosova B

Modernisation of AC/DC supply 2012

3

Replacement the line conductor 110 kV, L125/2 & L125/3 , (SSVushtrri 1-SSTrepçë-SS Vallaq)

Replacement the line conductor 150/25mm2 into 240/40mm2 , length 9.6km from SS Trepça up toSNS Vushtrria 1, and 11.4 km from SS Trepça up to SS Vallaqi

2012-2013

4 Rehabilitation of HV facilities at SS Ferizaji 1 & SS Gjilani 1

110 kV circuit breakers and disconnectors replacement 2013

5 Connection point of SS Lipjani at line 110 kV, L112

New double circuit line 110 kV, from SS Lipjani up to connection point at line L112. Connection with double circuit line 110 kV at the exsisting line L 112 SS Kosova A –SNS Ferizaj 1

2013

6 Allocation of L1806 line from SS Gjakova 2 up to SS Gjakova 1

Construction of double circuit line 110kV, 4km from the connection point line L1806 (SS Klinë-SS Gjakova 2) up to SS Gjakova 1 Total rehabilitation of SS Gjakova1 ( 110kV equipment). Transfer on double busbar.

2013

7 Rehabilitation of HV equipment at SS Prizreni 3

Replacement of three line fields 110 kV, of two transformer fields 110 kV and one coupling bay 110 kV. Replacement of protection equipment for three line fields.

2014

8

Rehabilitation of HV equipment at SS Gjakova 2

Replacement of three line fields 110 kV, of two transformer fields 110 kV and one coupling bay 110 kV. Replacement of protection equipment for three line fields.

2014

9 LFC- Secondary regulation

Project contains telecommunication routes, hardware and software equipment, which will enable the optimal implementation of the secondary regulation of both systems.

2014

10 New interconnection line 400 kV SS Kosova B - SS Kashar(AL)

New line 400 kV, 2x490mm2, length 239km of which 85.5km in the territory of Kosova. HV equipment, control protection and metering system

2015


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Four projects from the list 4, 6, 7 and 11) pertain to projects of enforcement of transmission

capacities. The major interconnection project 400 kV SS Kosovo B – SS Kashar is in the

process of selecting the bidders and is expected to enter into operation by 2015.

5.3.3. List of new development projects planned for the period 2013 -

2022

The following is a list of projects planned broken down by categories, as an outcome of an

optimal selection of various scenarios of network reinforcement during the planning process.

These projects span through the period 2013-2022. The projects are presented in tables

categorized as per respective specifics. A large number of these projects is part of the

Development Plan 2012-2021, as approved by the ERO, while there are some new projects,

resulting from a detailed analysis of the network during the planning process. Factors

considered influential in redesigning some earlier projects, in changing their implementation

period, and selection of some new projects, are processes which are not dependent on

KOSTT, such as: applications for new power or generation connections, funding security

aspects, property expropriations, etc. For the reasons mentioned above, the planning process

and projects selected are adapted to the changes which pursued in the meantime.

In addition, relevant impact in the review of priorities in planned investments is the

displacement of the technical boundary from the 110 kV level to the medium voltage level.

On this occasion, after analyzing and reviewing the technical situation of assets transferred

from KEK-DSO in KOSTT, projects are identified which are qualified with a high priority,

always calling in maintenance of the security of supply.

5.3.3.1. The list of new projects in the category of transmission network

reinforcement

The table 5-3 provides a list of projects planned for the next 10 years, which are considered

to be influential in establishing network capacities, pursuant to requirements of the Grid

Code. Projects are ranked according to their planned implementation period. Some of the

projects should be funded or co-funded by donors such as the IPA 2011 program, KfW etc.


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The commissioning date of the projects will depend on procedures implemented by donors.

Network performance analysis has shown that projects such as second transformer at SS

Peja 3 are necessary much earlier (2012-2013), but due to their incorporation with the IPA

2011 program, cannot be implemented earlier. For the IPA 2012 program, a certain number

of projects have been proposed, as shown in table 5-4. The vast majority of investments is to

be made by KOSTT with soft loans offered by the German Bank for Reconstruction

(KfW), while the remaining part shall be a donation of the European Union and investments

of the Kosovo Budget.

Table 5-3 List of projects planned for reinforcement of transmission network 2013-2022

PROJECTS OF CATEGORY: REINFORCEMENT OF TRANSMISSION NETWORK (2013-2022)

No

ID

Title of Project Technical Description Rationale

Year

1

T&

D T

R_

SK

EN

Second transformer 40 MVA in SS Skenderaj

a) Transformer TR2 110/10(20) kV , 40MVA b) 1 transformer field 110 kV and 10(20) kV completed

Increasing security and reliability of supply in Skenderaj. Optimization of the maintenance process of Substation. Creation of transformation reserves.

Q2-2

014

2

T-A

TR

/P

EJA

3

AT2-300 MVA in SS PEJA3 and SS FERIZAJ 2

(a) Auto-transformer 300 MVA, 400/110 kV ; (b) Installation of high voltage equipment for 400 kV and 110 kV transformer fields

Increase of transformation capacities and fulfillment of the N-1 security criterion. Q

4-2

015

3

T-L

PE

JA3-P

EJA

1

New line 110 kV SS Peja 3- SS Peja 1 and revitalization of SS Peja 1

a) 28 km, Al. Çe240 mm2; b) Line field in SS Peja 3; c) Revitalization of SS Peja 1 of equipment and busbar system in the level 110 kV , moving to dual busbar system and GIS system for 110 kV equipment.

Construction of the line enables the fulfillment of the N-1 criterion. In addition, Revitalization of SS Peja 1 affects the increase of security and reliability of system operation.

Q4-2

015

4

T-R

IV/

L12

6/

5

Revitalization of the line 110 kV : L126/2 SS Peja 2- SS Deçan

(a) Replacement of conductor from 150/25 mm2 to 240/40 mm2 in a distance of 14. 57 km from SS Peja 2 until SS Deçan (b) Reinforcement of concrete towers and replacement of existing insulators with composite insulation

Increase of transmission capacity of the line from 83 MVA to 114 MVA with the aim of reducing power losses, improving the N-1 security criterion for the substation ring110 kV Peja3-Peja1-Peja2-Deçan –Gjakova1.

Q4-

2015

5

T&

D T

R_

KL

INA

Second transformer 40MVA in SS Klinë


Increase security and reliability of Klina supply. Optimization of the maintenance process of Substation. Creation of transformation reserves.

Q2-2

018


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6

T-R

IV/

L16

3/

1

Revitalization of the line 110 kV : L163/1

(a) Replacement of conductor from 150/25mm2 to 240/40mm2 with a length of 32km from SS Kosova A until SS Vallaqi; (b) Reinforcement of concrete towers and replacement of existing insulators with composite insulation.

Increase of transmission capacity of the line from 83 MVA në 114 MVA with the aim of reducing power losses, improving the N-1 security criterion for the substation ring 110 kV Kosova A-Bardhi-Vaganica-Vallaq.

Q4-

2019

7

T&

D

TR

_B

UR

IMI

Second transformer 40MVA in SS Burim


Increase security and reliability of Burimi supply. Optimization of the maintenance process of Substation. Creation of transformation reserves.

Q2-2

020

8

T-R

IV/

L11

8/

3

Revitalization of the line 110 kV : L179/1 SS Prizren 1 – SS Prizren 3-

a) Replacement of conductor from 150/25mm2 to 240/40 mm2with a length of 4. 69 km from SS Prizren 1 to SS Prizren 3

Increase of transmission capacity of the line from 83 MVA në 114 MVA with the aim of reducing power losses, improving the N-1 security criterion.

Q3-2

020

9

TR

IV/

L15

5/

2

Revitalization of the line 110 kV : L155/2 in coordination with construction of SS Leposaviq 110/10 kV

a) Replacement of phased and protection conductors until (14km) b) Reinforcement of towers and replacement of insulators.

Strengthening transmission capacities and supporting the load in the northern part of Kosovo Q

4-2

020

10

T-L

2 P

Z1-

PZ

2

New line 110 kV SS Prizren 1- SS Prizren 2

a) 3. 5km, Al. Çe240mm2, b) Line field 110 kV in SS Prizren 2, c) Line field 110 kV in SS Prizren 1

Continuous growth of consumption in the region of Prizren risks the security of supply of substation ring Prizren 1, Prizren 3, Therandë. Ndërtimi i linjës se re transmetuese mundëson plotësimin e kriterit N-1.

Q4-2

021

11

T&

D T

R_

Beri

v

Second transformer 40MVA in SS Berivojcë


Increasing security and reliability of supply in Kamenica. Optimization of the maintenance process of Substation. Creation of transformation reserves.

Q2-2

021

12

T-L

2 P

EJA

3-U

JMA

N

New line 110 kV Peja 3- HC Ujmani

a) 25km, Al. Çe240mm2 b) Line field 110 kV in SS Peja 3 c) Line field 110 kV në HC Ujmani

Creation of new ring 110 kV Peja 3-Ujman-Vallaq and fulfillment of the N-1 criterion Q

3-2

022


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13

T/

RIN

G_

400 k

V

Package Project RING 400 kV GJAKOVË-PRIZREN-FERIZAJ

(a) Construction of the distribution system 400 kV SSH Gjakova 3 which includes 3 line fields and a connection field (b) Construction of SS Prizren 4, 400/110 kV, 1x300MVA in follow up of SS Prizren 2 which includes two 400 Kv line fields and one connection field 400 kV c) Construction of the 400 kV line, 31.5 km from SSH Gjakova 33 to SS Prizren 4 d) Construction of the line 400 kV, 56.5 km SS Prizren 4 - SS Ferizaj 2

Ring road configuration of the 400 kV network, with a view of optimizing load flows, support of new generation and load. Q

4-2

022

5.3.3.2. List of new projects, to support the load

After the transfer of 110 kV assets from the KEK-DSO to the KOSTT, the approach of

planning new 110 kV nodes pertaining to the category of load support has been revised.

Based on the applicable connection fee methodology in the transmission network, these

projects have been categorized as optional, and they appear in the plan only when an

application is submitted by the DSO, and received by the KOSTT, for their connection.

Currently, activities are ongoing in amending the connection fee methodology, thereby

reviewing more optimal approaches in the process of 110/x kV node planning. This

development plan, in a difference from the last year’s plan, four other projects of the load

support category are presented, harmonized with the priorities recommended by the KEK-

DSO development plan, approved by the ERO. The following table presents the load

support projects for the next 10 years:

Table 5-4 List of projects planned for reinforcement of transmission network 2013-2022

PROJECTS AIMED AT SUPPORTING THE LOAD (2013-2022)

Nr

ID

Title of Project Technical Description Rationale

Vit

i

1

T&

D-L

2/

MIT

2

SS Mitrovica 2 with 110 kV transmission lines

a) Dual line 0. 5km,110 kV connection in the line Vallaq-Palaj and dual line 0. 6km connection in the line Trepça-Vallaq. b) SS Mitrovica 2, 110/10(20) kV , 2x40MVA c) 2 transformer fields in 110 kV and 10(20) kV , 4 line fields 110 kV and connection fields 110 kV . c) command facility with ancillary equipment

Increase of security and quality of supply for the region of Mitrovica Q

4-

2017


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2

T&

D-L

2/

DR

AG

ASH

SS Dragashi and line 110 kV SS Kuks-SS Dragash- SS Prizren 21

(a) SS Dragashi, 2 transformation fields, 2 line fields and one connection field. b) Single line, 8km, Al. Çe240mm2 from SSPrizren 2 to Zhur (dual towers). c) Dual line 13km, Al. Çe2x240mm2 from Zhuri until SS Dragashi d) Single line 26km, Al. Çe240mm2 from Zhur until Kukës (from the border to Kukës 17km)

Optimization of operation of both systems of Kosovo and Albania. Quality and reliable supply for Dragash. Reduction of load flows at SS Prizren 1.

Q4-2

017

3

T-L

/M

AL

ISH

EV

A

Project Package SS Malisheva with 110 kV transmission lines

a) 110kV line Malishevë _Rahovec 16km, and line Malishevë -Therandë 16. 5km, Al. Çe240mm2 b) 2 transformers 31. 5MVA, 110/10(20) kV c) 2 transformation fields 110 kV and 10(20) kV , 2 line fields 110 kV , 1 connection field 110 kV . d) Command facility with ancillary equipment

Increase of security and quality of supply in the region of Malishevë, and fulfillment of the N-1 criterion for SS Rahoveci Q

4-2

018

4

T-L

/P

RIS

HT

INA

6

Package Project Prishtina 6 me dual underground cable 110 kV

a) GIS type substation, 110/10(20) kV , 2x40MVA b) two cable fields 110 kV b) two cables 110 kV , 1000mm2, with a length of 5. 5km c) 2 transformer fields in 110 kV and ne 10(20) kV , 1 connection field 110 kV . d) Command facility with ancillary equipment

Increase of security and quality of supply in the Prishtina center, Fulfillment of the N-1 criterion, reduction of technical losses and discharge of the capital’s 110 kV substations.

Q4-2

018

5

T-L

/F

_K

OS

OV

A

Project SS Fushe Kosova

a) Dual line connection 110 kV ,1. 5kM in the 110 kV line Kosova A- Lipjan (L112a) b) Substation 110/10(20) kV 2x40MVA me 2 transformation fields 110 kV and 10(20) kV , me 2 line fields 110 kV , me 1 connection field 110 kV c) command facility with ancillary equipment

Increase of security and quality of supply in the region of Fushë Kosove, si and fulfillment of the N-1 criterion. Q

4-2

019

5.3.3.3. Projects planned for the category of revitalization of KOSTT

substations

The following table contains a list of projects related to the process of revitalization of

substations managed by KOSTT.

Tab. 5-5. List of projects of the category of revitalization of substations

PROJECTS OF CATEGORY: REVITALIZATION OF SS (KOSTT) - (2013-2022)

Nr

ID Title of Project Technical Description Rationale Viti

1

TD

/R

IV_

GJ1

Revitalization of equipment of TM (35 kV ) in SS Gjakova 1

a)Replacement of 2 transformation fields 35kV , replacement of 1 Petersen reactance, replacement of connection equipment of the neutral of both transformers andb) replacement of dy mbrojtjeve rele te transformatorëve

To increase the security and reliability of substation’s operations Q

4-

2013

1Project SS Dragash with interconnection line 110kV in Kukes is presented in TDP 2012-2021


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2

TD

/R

IVG

JL1

Revitalization of equipment of TM(35 kV ) in SS Gjilani 1

a)Replacement of 2 transformation fields 35kV , replacement of 1 Petersen reactance, replacement of connection equipment of the neutral of both transformers and b) replacement of two transformer relay protections


4-

2014

3

T/

CB

_P

R4

Replacement of breakers in SS Prishtina 4

a)Replacement of breakers of 110 kV and 220 kV power, except two ATR3 fields


4-2

015

4

TD

/R

IVF

Z1

Revitalization of equipment of TM(35 kV ) in SS Ferizaj 1

a)Replacement of 2 transformation fields 35kV , replacement of 1 Petersen reactance and b) replacement of connection equipment of the neutral of both transformers .


4-

2015

5

TD

/R

IVP

2&

LP

Revitalization of equipment of TM(35 kV ,10 kV ) in SS Prishtina 2 andSS Lipjani

a)Replacement of 2 transformation fields 10 kV , replacement of 1 transformation field 35 kV ,replacement of 2 Petersen reactance and b) replacement of connection equipment of the neutral of both transformers in SS Lipjani .

To increase the security and reliability of substations’ operations Q

4-

2017

6

TD

/R

IV_

TH

ER

Revitalization of equipment of TLin SS Theranda

a)Replacement of two line fields 110kV , replacement of two transformation fields 110 kV and one connection field 110 kV. Move to dual busbar system. b) Replacement of two transformation fields 10 kV and one 35 kV . c) Replacement of field for own consumption

To increase the security and reliability of this important substation’s operations for supply for Theranda

Q2-2

018

7

TD

/R

_V

AL

L

Revitalization of equipment of TLin SS Vallaqi

a)Replacement of 5 fields of lines 110kV , replacement of two (2) transformation fields 110 kV . b) Replacement of 110 kV busbar systems and portals and replacement of a connection field 110 kV.

To increase the security and reliability of this important substation’s operations to supply a part of Mitrovica Q

4-2

019

8

TD

/R

IV_

VIT

Revitalization of HV equipment at SS Vitia

(a) Replacement of 2 110 kV line fields, replacement of (2) transformer fields 110 kV For own consumption 35 kV. b) Modernization of transformer protections.

To increase the security and reliability of this important substation’s operations for supply for Vitia

Q2-2

021

5.3.3.4. Projects planned in the category of supporting transmission system

operation

The following table provides the projects planned in the category of supporting transmission

system operation. This list was selected through an identification of transmission system in

complying to technical requirements as per Grid Code and those recommended by

ENTSO/E.

Tab. 5-6. List of projects in the category of support to system operation 2013-2022


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PROJECTS IN CATEGORY: SUPPORT SYSTEM - (2013-2022)

Nr

ID Title of Project Technical Description Rationale Viti

1

TD

_M

AT

JE Installation of metering

groups in the new boundary between KOSTT and KEK/DSO

a)Metering transformer of power in 35 kV and 10(20) kV levels in line with the metering code and associated works

Accurate metering in line with the metering code after the change of the technical boundary, namely the commercial border from 110 kV to 35 kV and 10(20) kV

Q3-2

014

2

T/

TE

LE

K_

OP

GW

OPGW installation at interconnection lines 400 kV - Installation of telecommunication routes by optical fiber, in 400 and 220 kV interconnection lines up to the borders.

(a) Existing protective conductor 65mm2 at 400 kV to the borders with neighboring countries will be replaced with another conductor of same dimension, containing 96 optical fibers.

Fulfilling technical requirements of the ENTSO/E Manual Q

3-2

015

T/

SC

AD

A_

Int

Implementation of changes and their incorporation in SCADA/EMS2

a) Inclusion of all changes in existing substations, and b) incorporation of new substations in SCADA/EMS in the Dispatch Center and Emergency Dispatch Center

Optimal use of the SCADA/EMS system

Q4-2

015

3

T/

MA

T_

NJE

HS

OR

E

INTER-OST Meters - Installation of metering points at cross border lines, in compliance with the Metering Code

(a) Installation of two-core metering transformers for commercial metering, same characteristics in 400, 220 and 110 kV interconnection lines (b) Replacement of existing meters with meters compliant to the Metering Code

The project allows for completion of installation of border meters, in accordance with the Metering Code. Q

4-

2015

4

T/

GIS

-SY

ST

EM

GIS System supporting the Transmission System

(a) Full set of remote controlled equipment: laser locator, thermal camera, digital area photo camera, GPS equipped, internal navigation system (b) Respective software for data integration and processing from equipment, and CAD and GIS data presentation

Improvement of maintenance of lines and substations. Data processing on pillars, line routes, identification of properties affected by lines, etc.

Q2-2

018

5.4. Technical description of projects planned in transmission

5.4.1. Introduction

The first stage of transmission network consolidation was completed with the completion of

the projects: SS Peja 3, L112 line, AT 150 MVA at SS Kosovo A. The second stage of

transmission network reinforcement, which enabled the enhancement of network reliability

security, in terms of N-1 criterion, was completed after the implementation of the SS Ferizaj

2Project with start in 2013 and is in process conform changes in network topology.


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Project and the connection of SS Gjilani 5. The transmission network planning process,

based on high voltage line planning criteria, is a dynamic one, and as such, it aims for

fulfillment of technical criteria which in the long term secure a safe prospect of load and

generation development.

The following is a description of development projects from the list of projects planned for

the period 2013-2022. A series of projects planned to complete by the end of 2022 will bring

the transmission network to a condition which guarantees security and high reliability in

operation, in full accordance with the Grid Code. This period includes projects which

influence directly the reinforcement of the transmission network, substation revitalization

projects and load support projects, for which the parties have applied to KOSTT for

connection to the transmission network.

5.4.2. Transmission grid strengthening projects

The following are detailed descriptions of planned projects pertaining the category of

strengthening or capacity increase of transmission grid, for the planning period 2013-2022.

Project: Second 40 MVA Transformer, 110/10(20) kV at SS Skenderaj

Within the Peja 3 Project Package, the first 110 kV substation was built in Skenderaj, but in

the absence of funding, the substation was only fitted with a single and used transformer

(1988) at power 31. 5 MVA. After the operationalization of substation, the performance of

transformer had serious difficulties with the transformer core, thereby resulting in frequent

failures of the substation, and full loss of supply for the consumers in the Skenderaj region.

The previous transformer capacities 35/10 kV were dismantled by KEK-DSO for use in

other parts of the Kosovo grid. The lack of alternative supply and technical problems in the

existing transformer have emphasized the urgent need to install a second 40MVA

transformer at SS Skenderaj. Also, operating with a single transformer is a major difficulty in

realizing maintenance works, when there are no other alternatives to supply consumption.

The project is given high priority, since the benefits of the project are:


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- Reduction of undelivered power to consumers,

- Increased safety and reliability of supply to Skenderaj and surroundings

- Increased transformation capacities

The project is planned for completion in the second quarter of 2014.

Project: AT2-300 MVA in SS PEJA3 and SS FERIZAJ 2

- Second AT 300MVA at SS PEJA 3,400/110 kV

The consistent increase of the load in the Dukagjini Plain region directly influences the

increased load in the single AT 300MVA at SS Peja 3. Computer analysis have shown that

during winter peak 2012-2013, around 3% (260 hours) of the year, the substation Peja 3

operates at risk as per security criterion N-1. The percentage of hours at risk will continue to

grow for 5% for the winter peak 2013-2014, and 7% for the winter peak in 2014-2015.

Figure 5-3 shows the power flows in PSS/E according to the forecasted load for the year

when the second transformer enters into operation. Based on planning criteria, the need for

a second transformer at SS Peja is rather pressing, but due to financial limitations, this

project was proposed for support from the IPA 2011 program. European Union procedures

for funding and implementing projects to be supported by the IPA program determine the

time of project commissioning, and this time is expected to be the fourth quarter of 2015.

Expected benefits from the project are:

- Enhancement of transformation capacities and fulfillment of the N-1 criterion of the

important 400/110 kV node

- Increasing the reliability and security of supply for 20% of the national consumption

- Reduction of the undelivered energy to the consumers.

- Optimization of the transformer maintenance process and their relevant fields.

- Creation of the conditions for 400 kV and 110 kV network reconfiguration (400 kV ring

and regrouping of 110 kV loads)


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Figure 5-3 . Power flows in two automatic transformers of SS Peja 3 after commissioning in the Q4

of 2015

- Second AT 300MVA at SS FERIZAJ 2, 400/110 kV

A consistent increase of load in southeast Kosovo (Ferizaj, Viti, Sharr, Gjilan, Theranda)

influences directly in the increased load on the single AT 300MVA at SS Ferizaj 2. The

second AT will influence the increased load flows from 400 kV to the 110 kV level at SS

Ferizaj 2, thereby relieving sensibly the load on AT-s SS Kosova A and SS Prishtina 4. With

the installation of the second auto-transformer, the substation Ferizaj 2, will comply to the

N-1 criterion for a long term, thereby increasing transformation capacities of the

transmission system for 300MVA. A project similar to the SS Peja 3 auto-transformer

project will be funded by the IPA 2011 program, the commissioning of which is expected in

the fourth quarter of 2015. The project envisages the financing of the installation of

AT2/300MVA/400/110 kV, from a transformer field 400 kV and 110 kV.

Figure 5-4 shows the power flows in PSS/E according to the forecasted load, for the year

when the second automatic transformer enters into operation.


Two lines 110 kV Up to SS PEJA 1

lines 110 kV Up to NS Burimi Line 110 kV

Up to Klina

Line 110 kV Up to SS Skenderaj

SS PEJA 3 400 / 110 kV


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- Enhancement of transformation capacities and fulfillment of the N-1 criterion of the

important 400/110 kV node

- Increasing the reliability and security of supply for 22% of the national consumption

- Reduction of the undelivered energy to the consumers.

- Optimization of the transformer maintenance process and their relevant fields.

- Creation of the conditions for 400 kV and 110 kV network reconfiguration (400 kV ring

and regrouping of 110 kV loads)

Figure 5-4. Power flows in two automatic transformers of SS Ferizaj 2 after commissioning in Q4-

2015

New 110 kV line SS Peja 3- SS Peja 1, and revitalization of SS Peja 1

Following completion of the L1806 line allocation project from SS Gjakova 2 to SS Gjakova

1, the Dukagjini Plain area will comply fully to the criterion N-1. Based on a long term load

forecast, and based on computer simulations, the security criterion N-1 will not be complied

with until after 2015. A critical outage would be the outage of 110 kV line SS Peja 3-SS Peja

1, in which case there would be an overload in the line SS Gjakova 1- SS Deçan and SS Peja

3 - SS Klina. For this reason, to eliminate this problem, it is necessary to build a second 110

kV supply line, 240mm2, at a length of 28km, from SS Peja 3 to SS Peja 1. The project

should be coordinated with the SS Peja 1 revitalization project, which provides for a full

rehabilitation of 110 kV equipment, and transition to the double bus bar system in the

compact GIS system including 35 kV transformer fields. This project is proposed for

DY LINJAT 110kV

deri NSFerizaj 1

Linja 110kV

deri NS Gjilani 5 Linja 110kV

deri NSLipjani

Linja 110kV

deri NS Sharri


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funding from the IPA 2012 program, while the commissioning of the project is expected in

the fourth quarter of 2016. Due to an over-urbanized area close to the Peja 1 substation, the

five pylons close to the substation must be constructed instead of existing pillars, and they

must be dual. If there are problems in property expropriation, an optional solution will be to

dismantle the existing line, and construction of a new doubled line, thereby avoiding a new

route. The figure 5-5 shows a geographical position of the project.


- Transmission network capacity enhancement and fulfillment of the N-1 criterion for a

long-term period for the network sections of the region of Dukagjini

- Reduction of active and reactive power losses in the transmission network.

- Reduction of undelivered energy to consumers

- Enhancing operational security and reliability of SS Peja 1 (substation built in 1961)

- Support for the integration of small hydropower plants in the energy system

Figure 5-5. Second line SS Peja 3- SS Peja 1


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Project: Second 40 MVA transformer, 110/10(20) kV at SS Klina

The substation 110/10 kV in Klina has had a single transformer in operation since its

construction in 1988. Operating with a single transformer poses a great risk in case of

unplanned failure of transformer, thereby leaving Klina without supply until repair. On the

other hand, consumption supply must have a transforming reserve, which responds to

continuous increase of load. For the reasons mentioned above, there is a need to install a

second transformer at SS Klina. Selection of substations with a single transformer for

installation of the second transformer took into account the age of transformer and technical

condition as recorded by maintenance teams.

The expected benefits of the project are:


- Increased safety and reliability of supply to Klina and surroundings


- Optimization of maintenance processes


Project: Second 40 MVA transformer, 110/10(20) kV at SS Burimi

Substation 110/10 kV in Burimi has only one transformer in operation since its construction

in 1989. Operating with a single transformer poses a great risk in case of unplanned failure

of transformer, thereby leaving Burimi without supply until repair. Also, there are serious

problems in performing maintenance of transformer and its plates, since this process also

requires full interruption of consumption supply. On the other hand, consumption supply

must have a transforming reserve, which responds to continuous increase of load. For the

reasons mentioned above, there is a need to install a second transformer at SS Burimi.

Selection of substations with a single transformer for installation of the second transformer

took into account the age of transformer and technical condition as recorded by

maintenance teams.




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- Increased safety and reliability of supply to Burimi and surroundings




Project: New line 110 kV SS Prizren 1- SS Prizren 2

The consistent growth of load in the Prizren region shall put at risk the N-1 criterion for that

area of the transmission network. This risk will be present after 2017, when the peak load in

Kosovo is foreseen to be 1340MW. The second 110 kV line from SS Prizren 1 to SS Prizren

2 is necessary since with the current network configuration, an outage of the line SS Prizren

2- SS Prizren 3 would cause an overload on the L164/3 line. The project plans for the

construction of a new 110 kV line, 240mm2 (114MVA/605A) 3. 5 km long, as shown in the

figure 5-6. In this case, there are two other options of implementation, depending on

difficulty of expropriation and urban obstacles:

- Transformation of the existing L164/3 line to a double line

- Underground 110 kV cable

The project is due to be completed by 2018. This project is important for the realization of

110 kV consumption grouping concept as per main substations. The same project is also

considered by the Fichner study on redesign of the configuration of the transmission

network 400 kV and 110 kV.


- Fulfillment of the N-1 criterion


- Enhancement of transmission network capacities

- Optimization of power flows and enabling the grouping of 110 kV loads

according to independent supply from main transmission system nodes (in this

case from SS Prizren 2)

The Project is planned to be completed in the fourth quarter of 2021


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Figure 5-6. Second 110 kV line SS Prizren 1- SS Prizren 2

Project: Second 40 MVA transformer, 110/10(20) kV at SS Berivojce

Substation 110/10 kV in Berivojce has only one transformer in operation since its

construction in 2002. Operating with a single transformer poses a great risk in case of

unplanned failure of transformer, thereby leaving Kamenica without supply until repair.

Also, there are serious problems in performing maintenance of transformer and its plates,

since this process also requires full interruption of consumption supply. On the other hand,

consumption supply must have a transforming reserve, which responds to continuous

increase of load. For the reasons mentioned above, there is a need to install a second

transformer at SS Berivojce. This substation is the last one in the list of four substations

currently operation with a single transformer.



- Increased safety and reliability of supply to Kamenica and surroundings



The project is planned to be completed in the second quarter of 2021.


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Project: New 110 kV line SS Peja 3- HPP Ujmani

A consistent growth of consumption in the Mitrovica region, and a single 110 kV line

connecting HPP Ujman with the transmission network, are factors necessitating

construction of a new 110 kV line to connect the plant with the strong network node SS

Peja 3. The figure 5-7 shows the geographical location of the 25 km long line. This project

allows for development of a new 110 kV ring road, which is important for the optimization

of the transmission network for the Mitrovica region. The expected consumption growth in

the region, especially due to the Trepca mine, will be more secure in terms of electricity

supply, in due consideration of increased transmission capacities. The new line will enable a

relief of supply lines for the 110 kV ring SS Kosova A – SS Bardhi – SS Vushtrria 1&2 – SS

Trepça.


- Fulfillment of the N-1 criterion for HC Ujmani

- Optimization of power flows in 110 kV lines, particularly discharging of supply lines of

SS Vallaqi

- Creation of necessary disconnection reserves during the maintenance process or during

unplanned breakdowns of the transmission system

- Valorization of transmigration capacities of Peja 3

The project is planned to be completed in 2022.


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Figure 5-7. Line SS Peja 3- HC Ujmani

Project Pack RING 400 kV GJAKOVA-PRIZREN-FERIZAJ

The current 400 kV network configuration is characterized as a star network, where the

centre of the star is the SS Kosova B. The optimal configuration of high voltage electricity

networks is the ring configuration, which ensures a higher operational flexibility and security

in the power system.

The expected development in terms of new generation capacities and load forecast, the

forecast of increasing flux of loads in regional exchanges, determine the need for

reconfiguration of the 400 kV network. Earlier studies, such as ESTAP I, have

recommended the reconfiguration of the 400 kV network in a ring form, thereby avoiding

220 kV network development.

Computer simulations undertaken in complex models, which incorporate regional systems,

in consideration of new generation capacity development scenarios in the country and the


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region, and the forecasted load development also in the country and the region, reflect the

need for creation of the 400 kV ring in the territory of Kosovo.

This configuration is presented as an optional long-term project also in the earlier

developments of KOSTT. A detailed study on redesigning of the 400 kV network, and its

impact on the Kosovo power system, was undertaken by a German consultancy “Fichner”.

The study’s concept recommends the establishment of powerful 400/110 kV nodes, which

are to supply load groups, and by establishing capacity reserves in 110 kV lines, with a view

of optimization of load flows. Computer simulations in complex models undertaken by

KOSTT have shown that the network area of the Prizren region will not be compliant to the

N-1 criterion after 2020, due to high impedance of two 220 kV supply lines of SS Prizren 2.

A larger problem would occur if the 220 kV interconnection line Fierzë-Prizren 2 would fail.

In this case, voltage collapse may occur, coupled with the disconnection of the load at SS

Prizren 2. If one would view the transmission network before the construction of the 400

kV ring, one would be able to spot the existence of four powerful and sufficient nodes of

transformation to 110 kV: SS Peja 3 supplying Dukagjini consumption, SS Ferizaj 2

supplying southeastern part and SS Kosovo A, together with SS Prishtina 4, which mainly

supply Prishtina consumption. All these nodes are connected to a powerful horizontal

network, while SS Prizren 2 remains connected also to a horizontal 220 kV network, which

is relatively poor.

All these nodes are connected to the powerful horizontal network, while SS Prizren remains

connected in the network also in the horizontal, but relatively weak 220 kV.

The 400 kV network reconfiguration from the star shape to the ring shape configuration

brings about the following benefits:

- Enables the support for new generation capacities

- Increases the 400 kV network’s reliability and security.

- Facilitates the security of power exchange between Kosovo and countries in the region,

or transits going through our network.

- Enables the reconfiguration of the 110 kV network with the aim of optimizing

operational conditions of the transmission system

- Enhances the quality of consumption supply in the region of Prizren.


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- Facilitates the 400 kV line maintenance process.

The ring project is expected to be completed in two phases:

First stage: Includes construction of the 400 kV distribution station Gjakova 3, which will

be positioned very closely to the 400 kV interconnection line SS Kosova B – SS Tirana 2,

where it should be connected at a length of 51 km from SS Kosovo B, as shown in the

figure 5-8. SS Gjakova 3 is expected to perform the function of the new interconnection

point in a 400 kV ring. It should include three 400 kV line fields, with a possibility of

expansion, and one 400 kV connection field. Simultaneously, the SS Prizreni 4 400/110 kV

will be developed, which initially will have an installed 300MVA auto-transformer. The

substation will be positioned in a sequence to SS Prizreni 2, to use the existing 100 kV bus

bars, with a difference in placing a 110 kV sectional bus bar divider. The substation provides

also for the development of double 400 kV bus bars, to contain two 400 kV line fields, and

sufficient space for reserve line and transformer fields. The figure 5-9 shows the

configuration of SS Prizren 4. Both substations would operate in parallel at the 110 kV level,

which means the use of existing 3x150MVA auto-transformers at SS Prizren 2. Existing

220/110 kV auto-transformers will be used to the end of their life cycle, to be replaced with

additional AT-s 400/110 kV to be installed at SS Prizreni 4. The distribution substation

Gjakova 3, 400 kV will be connected by a 400 kV line, 2x490mm2(1316MVA/1900A), at a

length of 31.5km with SS Prizren 4, 400/110 kV. The first stage is planned to be completed

in 2022.

Second stage: Includes the stage of ring completion, with the development of a 400 kV

line, 56. 5 km line from SS Prizren 4 to SS Ferizaj 2, as presented by figure 5-8. The

construction of this line may be completed in the period between 2022-2025, and must be in

timely coordination with generation capacity development projects.


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Fig. 5-8 Geographical positioning of the 400 kV ring SS Gjakova 3-SS Prizren 4- SS Ferizaj 2

TC

PR4

A

B

DR

NS Ferizaj 2

NS Peja 3

SSH Gjakova 3

NS Prizreni 4

Prz. 2

NISH

Krushevc

RIBAREVINË

TIRANA 2

Fierzë

SHKUPI 5

31.5km

56.5km


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Figure 5-9. Single pole scheme of modified substation SS Prizren 2, 220/110 kV to SS Prizreni 4,

400/110 kV

5.4.3. 110 kV line revitalization projects

The important factors that are taken into account for determining the list of lines which will

have the conductors replaced with larger transmission capacity are:

- The age of the lines,

- Line overload frequency (N-1)

- The level of power losses in the line

The first factor is clearly defined; while the second and third factors are identified by

computer analysis, thereby simulating load flows for different transmission system operation

conditions, in due consideration of perspective development of projects, which would

considerably impact the change of load flows in the transmission network. All 110 kV lines

with 150mm2 section, in the transmission network, have been analyzed in terms of load

losses, thereby pursuing reinforcement at the long term.

300 MVA

SY GJAKOVA 3 SS FERIZAJ 2

Reserve .

Reserve

3 x 150 MVA

400 kV 220 kV

110 kV 110 kV

coupling bay

coupling bay

coupling bay

Lines 110 kV Lines 110 kV Lines 110 kV

disconnetor


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Lines that are 40 years old and lines with larger overload frequency and, understandably,

higher losses, are listed in the first place.

The main objective of this category of projects is to increase the capacity of 110 kV lines

with section conductors of 150mm2 (83 MVA), in conductor 240mm2 (114 MVA). Some

very old lines mainly have concrete towers and replacement of the existing conductors with

conductor on greater weight in mechanical and statically terms require reinforcement of

towers, with special emphasis on angular towers. Also portal towers require reinforcement

and eventual addition of the towers in order to increase the mechanical stability of the whole

line. The following 110 kV lines are selected for reinforcement for period 2013-2022:

Revitalization of the 110 kV line: SS Peja 2-SS Deçan, L126/2

Line of 14. 57 km connecting SS Peja 2 with SS Deçan, presented in figure 5-10, is a line

built in 1967, which contains 52 towers of portal type and conductor of 150mm2. Line

L126/2, is an important line, segment of the substations ring of 110 kV Peja 3 – Peja 1, -

Peja 2 - Deçan-Gjakova 1.

The project for the revitalizing of this line includes strengthening of the angular towers of

the portal form, installing new insulators and changing phase conductors. Protective

conductor will be replaced with the project SCADA/EMS. The project will assist in the

increase of the transmitting capacities and will assist in improvement of the N-1 security

criteria.


- Enhancing the transmission capacity of the line from 83 MVA to 114 MVA

- Reduction of active and reactive power losses

- Fulfillment of the N-1 criterion for the section of the network connecting 110 kV

substations of the Dukagjini region

The project is planned to be finalized in the fourth quarter of 2015.


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Fig. 5-10 Line 110 kV SS Peja 2 – SS Deçan with a length of 14. 57km

Project: Revitalization of the 110 kV line SS Kosova A- SS Bardhi – SS Vallaqi

From all results obtained from computer simulations, the current line L163 from Kosovo A

to SS Vallaq at the capacity of 83MVA (150mm2) seems to be more problematic in

comparison to other lines (150mm2) which are in the list for replacing conductors. After the

completion of the project of reinforcement of SS Bardh supply, whereby connection of SS

Kosovo A – SS Vallaq was completed, a part of the line remained with the section 150mm2,

therefore the project as a whole includes the revitalization of this section. Improvement of

capacity of this line should relief its overload, in the case of disconnection of supply line SS

Kosova A – SS Vushtrri 2. The same line with connect SS Mitrovica 2 as well, allowing for

an improvement of security and reliability of supply for the load in the Mitrovica region. The

figure 5-11 presents the part of the line planned for revitalization. The Project includes

replacement of conductors 150mm2 (83MVA/440A) with 240mm2(114MVA/605A)


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conductors, and necessary reinforcement in portal pillars, due to the added load on the

conductor.


- Enhancement of line transmission capacity from 83 MVA to 114 MVA


- Fulfillment of the N-1 criterion for the section of the network connecting the ring:

Kosova A-Bardhi-Vushtrria 1&2-Trepça-Mitrovica 2-Vallaq

The project is planned to complete by the fourth quarter of 2019.

Fig. 5-11 Line 110 kV SS Kosova A – SS Bardhi – SS Vallaq with a length of 38. 5km

Project: Revitalization of 110 kV line, SS Prizren 1 – SSPrizren 3

The project provides for replacement of conductors, from 150/25mm2 to 240/40mm2 at a

length of 4. 69km, from SS Prizren 1 to SS Prizreni 3, as presented by figure 5-12. The

project also provides on static reinforcement of existing pillars, placement of new composite

insulators, and replacement of phase conductors.


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The line is an interconnecting segment for the supply of SS Prizren 3. Revitalization of this

line shall substantially impact the increase of security and operating reliability of that part of

the 110 kV network.


- Fulfillment of the N-1 criterion for the section of the 110 kV network connecting 110

kV substations in the region of Prizren

- Enhancement of line transmission capacity from 83 MVA to 114 MVA


The project is planned to be completed by third quarter of 2020.

Fig. 5-12 110 kV line SS Prizren 1 – SS Prizren 3 with a length of 4. 69 km

Project: Revitalization of the 155/2 line, in coordination with development of the SS

Leposaviq 110/10 kV

The new SS Leposaviq 110/10(20) kV is planned to he supplied by the existing cross border

line SS Vallaq - SS N. Pazar, which shall be realized by a section close to the SS Leposaviq

35/10 kV . The line currently does not have sufficient capacity due to its sectional width

(150mm2). On the other hand, this line is one of the oldest lines of the transmission system

of Kosovo, therefore its reinforcement is necessary. Replacement of the conductor is


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planned for 15km of the line, starting from SS Vallaqi to the point where the section is

planned to occur in the line L155/2. The figure 5-13 shows the geographical position of the

project.


- Enhancement of the line transmission capacity from 83 MVA to 114 MVA


- Enabling the realization of SS Leposaviq 110/10(20) kV

The project is due to complete by the fourth quarter of 2020

Fig. 5-13 Revitalization project for the line L155/2 in coordination with construction of SS Leposaviq 110/10(20) kV .


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5.4.4. Load support projects

The following are technical descriptions of projects supporting the load and expected

benefits from them

Project No. 5: SS Mitrovica 2, 110/10(20) kV

The continuous increase in electricity demand in the area of Mitrovica raise the need

for creating a new distribution facility in the area. The southern part of Mitrovica is currently

being supplied by the substation in the Industrial Complex of Trepça. The current capacities

of the distribution grid are limited, and during peak loads, 35 and 10 kV lines and cables are

overloaded. On the other hand, the mining and metallurgic industrial development requires

special, safe and independent supply. These are the factors necessitating the construction of

an SS Mitrovica 2, 110/10(20) kV, transforming capacity 2x40MVA, close to the existing

distribution substation 35/10 kV.

The optimal position of the new substation is in the proximity of the existing 35/10 kV

substation next to the sports stadium “Trepça”, in lieu to which the Municipality of

Mitrovica has already allocated the plot for the substations and line routes.

Based on the principle of security of operation of Transmission System, Mitrovica 2

should be built close to the existing lines L125/3 Trepça-Vallaq and L163/2 Palaj-

Vallaq. Apart from the short double line 300m, the connection will be made with the

110 kV line Palaj-Vallaq, while a second connection will be made by double line

400m with the 110 kV line Trepça – Vallaq. Figure 1-1 shows the connection to the

substation Transmission Grid. By this topology, this substation shall provide good

security in terms of N-1 security criteria, and as such, it will be an important 110 kV

node for the energy system of Kosovo. The expected benefits of the project are:

- Reliable and qualitative supply of consumption in Mitrovica

- Reduction of large amounts of undelivered power, as a result of elimination of

bottlenecks in the distribution grid

- Reduction of technical losses in the distribution network


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- Support to economic development of Mitrovica

The project is planned for completion in the fourth quarter of 2017.

Fig. 5-14 Connection of SS Mitrovica 2 in the Transmission Network

Project: SS Dragash and 110 kV line SS Kukës-SS Dragash- SS Prizren 2

The project includes the development of SS Dragash 110/10(20) kV to be supplied with two

lines: SS Dragashi – SS Prizreni 2 (21km) and SS Dragashi - SS Kukës (39km). From Zhur to

Dragash, the line shall be double, while from Prizren 2 to Zhur, the line will be single, but

with doubled pillars, so that the other pillar line is used for the HPP Zhur project. The

Figure 5-15 presents the geographical location of the project, with relevant data. The project

coordinated between KOSTT and KEK-DSO is considered to be of importance for both

parties. For KEK_DSO the project allows for a better supply for the southern area of

Kosovo (Dragash and surroundings), reduction of technical losses at distribution, and relief

of 110/35 kV transformers at SS Prizreni 1.

In terms of benefits created by the transmission system project, we can underline a

few:

- Optimization of load flows between two systems KOSTT (Kosovo) and OST (Albania),

and minimization of electricity generation costs for both system generators.

SS MITROVICA 2 110 / 10 ( 20 ) kV

SS Trepça

SS PALAJ

SS Vushtrria 1

SS VALLAQ

HPP Ujmani SS N . Pazar

6 km

28 . 9 km

8 . 89 km

9 . 1 km

10 ( 20 kV )

40 MVA 40 MVA


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- Relief of load from 110 kV lines SS Prizren 1-SS Prizren 2 and SS Prizren 1-SS Prizren 3,

equivalent to the Dragash load.

- Exchange of electricity surpluses between systems, which can be facilitated by radial

operation.

- Secure supply for SS Dragash and SS Kukës, thereby fulfilling the N-1 criterion (outage of

a line does not interrupt supply for SS Dragash or SS Kukës, due to doubled supply)

The project is expected to be operational by the fourth quarter of 2017.

Figure 5-15. Project of SS Dragash and line 110 kV with SS Kukës.

HPP Dikance

SS Zhuri 35 kV

SS PRIZRENI 2 220 / 110 kV

SS PRIZRENI 1 110 / 35 kV

8 . 4 km

SS Kuksi

SS Dragashi 35 kV

Line 35 kV

SS DRAGASHI 110 / 10 ( 20 ) kV

Double circuit line 110 kV Dragash - Zhur , 13 km

Zhuri

One circuit line ** 110 kV Prizren 2 - Zhur , 8 km

** Double towers for HPP Zhuri

One circuit line

110 kV Zhur - Kukes 26 km Zhur - -border 17 km


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Project: Project Package Malisheva 110/10(20) kV

Following the transfer of 110 kV assets from KEK-DSO to the KOSTT, the process of

planning 110/10(20) kV substations for load support was taken by KOSTT, in due

harmonization with plans and priorities, and in connection to load support. The project

package Malisheva was included with the list of capital projects for load support and

strengthening transmission capacities of the network for the following reasons:

a) The condition of supply for the Malisheva is unsatisfactory, since this region is currently

supplied by a 35 kV line from SS Rahoveci. The length of this line causes large losses of

active and reactive power, thereby adversely influencing the quality of electricity

delivered to consumers. The 35 kV voltage level and other distribution levels during the

winter load are below minimum allowed values according to the distribution code. To

be able to provide for sustainable and long-term supply of electricity for the Malisheva

region, it is necessary to construct a 110/10(20) kV substation, with transformation

capacities of 2x31. 5 MVA.

b) The implementation at SS Malisheva shall be made in a way of creating a 110 kV ring,

which would connect SS Malisheva with SS Rahovec with a 17 km line, and SS

Malisheva with SS Theranda with a 19 km line. In this case, the radial supply of SS

Rahoveci will be eliminated, transformers at SS Rahovec are relieved, and a load group

Rahovec, Malishevë, Therandë will be created, supplied in turn by the strong node of SS

Prizren 2. This shall optimize the load flows, it will increase disconnection reserves,

while the line Therandë-Ferizaj 1 may operate remaining open or closed, depending on

the load flows and the system security assessment.

The two 110 kV lines shall be of 240 mm2 in dimension. This project is to be coordinated

with the equipment revitalization project at SS Theranda, which envisages the replacement

of 110 kV equipment, and migration to the double busbar system. At SS Rahovec, there is an

existing 110 kV line field, while at SS Theranda, a new line field must be constructed. Figure

1-2 shows the geographical coverage of the project package.



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- Reliable and quality supply of consumption in Malisheva

- Development of a new flexible 110 kV ring Rahovec - Malisheva - Theranda

- Elimination of radial supply for SS Rahoveci (N-1 Criterion)

- Optimization of load flows and discharge of transformers at SS Rahovec

- Reduction of large amounts of undelivered power to the consumers, as a result of

elimination of bottlenecks in the distribution network

- Reduction of technical losses in the distribution grid

- Support to economic development of Malisheva

The project is planned for completion by the third quarter of 2018.

Figure 5-16 Geographic position of the project package SS Malisheva

SS RAHOVECI SS THERANDA

SS MALISHEVA 110 / 10 ( 20 ) kV 2 x 31 . 5 MVA

SS Malisheva 35 / 10 kV

Existing line 35 kV

Line 110 kV , 240 mm 2 , 15 km

Line 110 kV , 240 mm 2 , 17 km

Line 220 kV SY Drenas - SS Prizreni 2

In SS Ferizaj 1

In SS Priz . 1

In SS Prizreni 2


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Project: SS Prishtina 6, 110/10(20) kV

In terms of security of supply for distribution consumers, the construction of the

new Prishtina 6 substation in the center of Prishtina is necessary, due to the fact that the

current capacities of distribution substations SS Prishtina 1, SS Prishtina 2 and SS Prishtina 3

will not be sufficient for a middle-term period. The consumption in Prishtina and its

surroundings is the highest in Kosovo, making around 25% of the national consumption.

The problems in distribution capacities increase during winter consumption, and specifically

exacerbating when the District Heating Company has difficulties, thereby increasing the

demand for electricity. The position proposed for the new substation is in or close to the

closed building of SS Prishtina III 35/10 kV, which is located close to the main offices of

KEK and KOSTT. The geographical position of the substation, in the urban area, clearly

determines the options of supplying the substation, therefore underground cable. Also, the

type of high voltage equipment should be modular/compact, or so-called “GIS” technology,

which requires smaller space for construction. The figure 1-3 shows the proposed site for

the substation.

Figure5-17. Geographical position of the two substations Prishtina 4 and Prishtina 6.


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Based on the satellite images, one may see that the pipelines must be laid in rather

urban areas, especially in the proximity of SS Prishtina 6. The connections mentioned above

are also presented with the earlier development plans for the Transmission grid. Figure 1-4

shows the projected configuration of connection of the SS Prishtina 6 to the Transmission

grid. According to information from the Department for Project Implementation, earlier

plans of the KOSTT had defined the cable line routes, and the urban consent had also been

given for the route, issued by the Municipality of Prishtina. The route was 5. 3 km long,

while due to the stalling of the project, numerous constructions have taken place on and

along the route, which necessitate the deviation of such a route. Joint KOSTT-DSO teams

have intensified their visits to the Municipality of Prishtina, with a view of defining clearly

the new route for 110 kV lines.


- Reliable and quality supply for the consumption of the centre of the Capital

- Relieved transformers at SS Prishtina 1, 2 and 3


- Optimization of load flows in 110 kV lines, as a result of discharging transformers

at SS Prishtina 1, 2 and 3

- Reduction of large amounts of undelivered power to the consumer, as a result of

eliminating bottlenecks in the distribution network


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Fig. 5-18 Configuration of connection of SS Prishtina 6, 2x40 MVA, 110/10(20) kV to the

transmission grid

Project: SS Fushë Kosova 110/10(20) kV

The list of priority projects of the KEK-DSO includes the construction of the substation

Fushë Kosova 110/10(20) kV, close to the existing substation 35/10 kV. This substation is

supplied by two 35 kV lines, 95 mm2 from SS Kosova A and SS Prishtina 1. Based on the

information from the KEK-DSO, 35/10 kV transformer capacities are close to the critical

limit, while on the other hand, the load in the region of Fushe-Kosove shows a tendency of

continuous growth. For this reason, there is a necessity of creating a new 110/10(20) kV

node in Fushë Kosovë, which should have sufficient long-term transforming capacities in

2x40MVA, which would be able to respond to the continuous load growth, in accordance

with technical criteria of transformation reserve. The construction of the substation should

allow for the relief of transformers at SS Prishtina 1 and SS Kosova A, and reduction of load

flows in supply lines of the SS Prishtina 1. In the technical aspect of connections, based on

the geographical position of the substation, the optimal position of connection with the

transmission grid would be the 110 kV L112 line SS Kosova A- SS Lipjan, which passes

close to the position proposed. The geographical position of the connection of SS Fushë

Kosova is presented in the figure 1-5. A double line of around 1 km in length, standard


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dimensions of 240mm2, will be connected to the 110 kV Kosova A- Lipjan line point at a

distance of 4. 3 km from Kosova A. In this way, an optimal use of the line earlier converted

from 220 kV to 110 kV is achieved, by supplying two substations SS Lipjan and SS F.

Kosova.


- Reliable and quality supply of consumption in Fushe-Kosova

- Relieved transformers at SS Prishtina 1 and SS Kosova A


- Optimal usage of converted L112 line (Kosova A-Lipjan – Ferizaj 2)

- Optimization of load flows at 110 kV lines, which supply substations of Prishtina, as a

result of relieving transformers at SS Prishtina 1 and Kosova A

- Reduction of large amounts of undelivered power to the consumer, as a result of

elimination of bottlenecks in the distribution network

The project is scheduled for completion by the fourth quarter of 2019


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Figure 5-19. Configuration of connection of SS Fushë Kosova to the transmission network.

Existing 110 kV line SS Kosova A-SS Lipjan

SS F.Kosova

SS KOSOVA A

Connection point

4.3 km far from SS

Kosova A

Double 110 kV line 1 km, 240mm2


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5.4.5. Substation Revitalization Projects

In determining the list of substations that required revitalization the following factors were

taken into consideration:

- Impact of the failure of the substations in the transmission system

- The age of the substation

- Frequency of the failures and damages in the equipments of the high voltage

- The level of the fault currents in the substations

Probability of failures in high voltage equipment begins to rise with age of equipment,

especially equipments that are greatly used. Also the substations which are characterized by

large currents failures considerably influenced in the accelerating the loss of their credibility.

Based on data archived in KOSTT related to the above mentioned factors a list was drafted

of substations requiring revitalization in the first five years of the development plan.

Project: Revitalization of equipment in TM at SS Gjakova 1, SS Gjilani 1 , SS Ferizaji

1 and SS Lipjani

Within the activities after the transfer of assets from the KEK-DSO to the KOSTT,

pursuant to the decision of the Government, the assessment of the technical condition of

equipment in terms of their impact on reliability and security of operation of the

Transmission System is essential and necessary, for development planning within the

Transmission Development Plan to be adequate and optimal. In the process of initiating and

completing activities for asset transfer, technical working groups and sub-groups have

collected important data, which were helpful in enabling a proper and real assessment of the

technical asset condition. In having a more detailed overview of technical equipment,

additional visits were arranged to the 110/x kV substations, specially focusing on substations

constructed before 2000. During the process, detailed monitoring was made on the

following components:

- Transformers 110/x (technical parameters, age, physical condition)


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- Transformer neuters and connection equipment

- Transformer plates 35 kV and 10 kV

- Own-consumption fields 35/04 kV or 10/04 kV

- AC/DC system

- Transformer overvoltage dischargers

Based on the current condition of the Kosovo Energy System, the process of asset transfer,

after the displacement of the technical limit from the high voltage to medium voltage levels,

incorporates the following:

- 1 SS 220/35/10 kV

- 6 SS 110/35 kV

- 7 SS 110/35/10 kV

- 14 SS 110/10(20) kV (together with two new SSs in the process, SS Gjilani 5 and SS

Prishtina 7)

As part of the 54 transferred transformers, there are 5 triple-reel transformers with

transformer fields of 35 kV and 10(20) kV.

Total transferred:

- 59 transformer fields (35 kV and 10 kV )

- 28 fields of own consumption

- 28 AC/DC systems

The equipment is divided into age groups, those built before 2000, and those after:

Built before 2000 (old system):

- 13 transformer fields 10 kV and

- 17 transformer fields 35 kV

after 2000 (new system):

- 23 transformer fields 10 kV and


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- 6 transformer fields 35 kV

In total, closely 50% of transformer fields may be considered to be relatively new, and up to

new. The other half may be categorized in various ages, from 26 to 46 years in age.

Within a detailed analysis of the technical condition, and age of equipment transferred, a

certain number of projects is ranked according to priorities in the development plan. This list

of projects, which did not take place in the TDP 2012-2021, includes revitalization of

medium voltage equipment, managed by KOSTT, at substations:

SS Gjakova 1, SS Gjilani 1, SS Ferizaji 1 and SS Lipjani

The project shall be implemented in the next 5 years, according to the priorities listed in

Table 5-5.

This package envisages the replacement of transformer fields 35 kV, internal and external

construction, connection equipment of transformer neuters, and modernization of

transformer relays.

Expected benefits of the Project:

- increased security and reliability of substation operations

- reduction of undelivered power, as a result of interruptions caused by failures

- improved safety of personnel working at the substation, and maintenance personnel

The project shall be implemented in the period 2013-2017

Project: Revitalization of SS Theranda:

This project is of special importance, since it is related to the construction of SS Malisheva

where a new 110 kV line SS Rahoveci- SS Theranda will be connected in this substation. The

current bus bar (H system) configuration of the SS Theranda does not allow for an


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optimization of system operation, while representing a difficulty in the process of

maintenance. Based on planning standards, substations that have three or more lines must be

configured in double bus bar systems and connection fields. This project envisages the

replacement of existing 110 kV high voltage equipment, development of a double bus bar

system (360mm2), installation of a 110 kV connection field, and the replacement of medium

voltage transformer fields. The existing relay protection system in line fields is planned to be

replaced with modern numeric relays. The project package SS Malisheva with the 110 kV

lines, and the substation revitalization project must be integrated in a joint project.

Benefits from the project are:

- Enhancement of the substation operation reliability and security

- Optimization of the substation operation after the transfer to dual busbar system


- Increase of the safety of staff members working in the substation and maintenance

teams

Project: Replacement of the switchgear in SS Prishtina 4:

SS Prishtina 4, 220/110 kV , 3x150MVA, is a very important transformation node in

Kosovo’s transmission system. Substation Prishtina 4, due to its proximity with the existing

and planned generation capacities, with the high level of flows, may risk the dynamic system

stability. Historical data of incidents recorded as a result of failures in switchgear show their

importance. This project is selected to apply for funding by the IPA 2012 program, and as

such, it is planned for implementation by the fourth quarter of 2015.

Benefits from the project are:

- Enhancement of the substation and transmission system operation reliability and security

in general

- Reduction of undelivered energy to consumers as a result of reduction of frequency of

breakdowns in switchgear, after their replacement.

- Adequate dimensioning of switchgear in line with the code of electrical equipment


teams


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Project: Revitalization of SS Vallaqi Substation:

SS Vallaqi was one of the first substations to be built in Kosovo. Revitalization of this

substation is necessary, due to the fact that 5 110 kV lines are connected to its 110 kV bus

bars, one of which conveys the load generated by the HPP Ujmani. The technical condition

of the substation is not satisfactory, and as such, it hampers the security and reliability of

consumer supply. Revitalization of the substation includes replacement of 110 kV high

voltage equipment, replacement of busbars and portal systems with double busbars and

connection lines. The project is due to finish by the fourth quarter of 2019.



- Optimization of the substation operation after the transfer to dual busbar system



teams

Project: Revitalization of Substation SS Vitia:

Exploitation of high voltage equipment for the substations in question, built in 1984, until

the planned time period for revitalization is economically feasible. If one refers to the age of

substations, frequency of outages and the technical state of equipment, their operation is

considered feasible for another 5-9 years.

Substation of Vitia represents a node which belongs to an important ring 110 kV : Sharr-

Viti –Gjilan 5 –Gjilan 1. Modernization of high voltage equipment, medium voltage

equipment which belong to KOSTT, and protection equipment, will have an effect in

increasing the operational security and reliability of this section of the transmission network.

Revitalization of 110 kV high voltage equipment at SS Vitia, 110/35 kV is planned to be

completed by 2021.

Expected benefits are:



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teams

5.4.6. Projects to enhance monitoring, control and measurement

systems in the Transmission System

The following are TDP projects considered necessary to fulfill the requirements of the Grid

Code and ENTSO/E manual.

Project: Installation of metering groups in the new boundary between KOSTT and KEK/OSSH

The project of installing metering groups in the new commercial boundary with KEK-DSO,

after the displacement of such boundary, is considered to be a project of high priority. The

project envisages for the installation of current and voltage metering transformers in all

transformer fields in 35 kV and 10(20) kV levels, in transformers transferred from KEK-

DSO to the KOSTT. Metering transformers must have technical features in compliance with

metering code. Meters from the earlier metering points will be used, only replacing entry

sizes, which were earlier taken from the 110 kV metering transformers, while now from the

35 kV and 10(20) kV transformers. The project is scheduled to be completed by the third

quarter of 2013.

The expected benefits from the project are:

- Electricity metering transferred from KOSTT to the KEK-DSO pursuant to the

metering code

- Accurate metering of losses in the transmission network, including the 110/x kV

transformers


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Project: OPGW in the interconnection lines

Currently there are no telecommunications routes OPGW at the boundary lines.

Requirements of Policy 6 of the Manual of ENTSO/E (UCTE) require that an OST must

have at least two lines of communication with neighboring systems. Therefore, the project of

establishment of OPGW in the interconnection lines up to the border point is considered

important for KOSTT and regional system as a whole. In order for the project to be

operational there should be an Agreement between TSO’s so the OPGW will be installed in

the entire length of the line on both sides of the border.

The main objective of this project is installation of protective conductor with OPGW (up to

the border with neighboring TSO) and telecommunications equipment in the existing

interconnection lines of 400 kV:

- L 407, SS Kosova B – SS Nish, with a length of 41 km

- L 437/2 SS Peja 3 – SS Ribarevina , with a length of 28. 8. km

- L 420 SS Ferizaj 2 – SS Shkupi 5, with a length of30. 6km

Total length of the OPGW installment is 100. 4km

The project was presented in IPA 2011 and is planned to be implemented in the third

quarter of 2015.


- Fulfilling the technical criteria from the ENTSO/E manual

- Exchange of data with neighboring systems

- Increasing operational safety of regional transmission systems

Project: Implementation of changes and their incorporation in the SCADA/EMS

Continuous development and change in the transmission network, namely construction of

new substations, require integration with the existing SCADA/EMS system. This is

necessary after any changes in configuration, with a view of achieving optimal usage of the

SCADA/EMS system. This project is also connected to the projects undertaken by KEK-

DSO, which are not integrated with SCADA/EMS, such as SS Prishtina 7, SS Gjilani 5 etc.

The project is continuous and permanent, in terms of time period, and as such it is planned

to conclude by the end of 2015. The expected benefits of the project are:


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- Increased security and reliability of transmission system operation

- Correct usage of SCADA/EMS applications in the analysis of transmission system

performance

- Monitoring and command of the whole transmission system

- Fulfillment of technical criteria provided upon by the ENTSO/E Manual

Project: INTER-TSO Meters

Currently there are measuring points in all interconnection lines; however, they are not

completely in compliance with the Metering Code and the technical requirements of

ENTSO/E. The problems fall in two aspects:

- Current and voltage metering transformers have only one core for measuring, while the

Metering Code requires to have two commercial cores with identical characteristics.

- Meters should be of multiple tariffs

Project foresees replacement of the measuring points in the interconnection lines:

- Line 400 kV: SS Kosova B – SS Nish

- Line 220 kV: SS Podujeva – SS Krushevc, SS Prizreni 2 – SS Fierza

- Line 110 kV: SS Vallaqi – SS N. Pazari, SS Berivojca – SS Bujanovci

Also the project will include three other measuring points in SS Kosovo B in the border with

PP Kosova B:

- Line 220 kV, SS Kosovo B – PP Kosovo B

- Two generation fields B1 and B2 in SS Kosovo B.

This project will complete the measuring points in all border of the transmission system with

others.

This project was also presented in IPA 2011 and is expected to be implemented in the

fourth quarter of 2015.

- Metering electricity between KOSTT and neighboring systems in line with the

metering code.


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Project: GIS System in support of Transmission System

The geographical information system (GIS) is to be used for organizing and processing of

transmission data for the whole territory of the Republic of Kosovo. The main feature of the

GIS system is the possibility of spatial/geographical data inter-relation, classification of all

technical details of transmission assets in correlation with the surrounding areas. The GIS

system also allows for communication with other IT systems.

The application of a GIS system in the Transmission System would enable:

- Accurate geographical positioning of line (pillars) and substations, information on properties in

and around installation positions.

- Detailed Technical information on each line (pillar), substation, telecommunication antenna, etc

- Information on property structure and construction in routes planned for new lines.

- Remote communication by equipment such as: thermal vision cameras, laser height meters, GPS

photo cameras, logistical means of GPS equipped maintenance teams.

- Data collection and processing inside a single collection centre.

- Communication with other IT systems

Benefits from the GIS system are rather large, both in terms of savings in the maintenance

process, and in the process of operational and long term planning. This system shall also

integrate a system for identification of intensity and positioning of lightning discharges,

which would contribute in further enhancement of preventive maintenance. The project is

due to be completed by 2018.


- Minimization of transmission network maintenance costs

- Optimization of the planning and maintenance process, reduction of action time

- Systematization of technical data


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5.5. Rationale for changes in projects of the TDP 2013-2022 in comparison to the

TDP 2012-2021

The current development plan has differences in the project list and their implementation

periods, in comparison to the TDP 2012-2021. Main reasons for such changes are:

- Displacement of technical and commercial boundaries between KOSTT and

KEK-DSO

- Applications for connection to the transmission network unforeseen with the past

plan

- Optimization of distribution of capital costs in years.

In many transmission systems in European countries and wider, planning criteria are similar

to criteria applied by KOSTT in long-term planning processes of the transmission system.

The fulfilment of the N-1 security security is rather challenging even for the most developed

countries, due to the high investment costs in such realization. For this reason, KOSTT also

takes into consideration the costs of reaching system operation security criteria in its

planning processes. The main objective is to fulfill such criteria within the shortest period

possible. The technical criteria of operation security require time to be met, while additional

information is provided to the ERO. The selection of projects to be postponed in periods

derives from a technical analysis of all projects, their degree of influence in the system

reliability and security, and priority setting based on benefits provided by these projects.

The displacement of the boundary from 110 kV to the medium voltage level between

KOSTT and KEK-DSO is the main factor necessitating the inclusion of new projects, and

postponement of projects in time. The assessment of the technical condition of transferred

assets has brought the emergency and additional investment needs to surface. Also, the

approach taken in planning 110/x kV substations has changed to some extent, thereby

causing additional responsibilities for KOSTT in planning, and in coordinating with KEK-

DSO plans. The ultimate approach in planning substations to support the load shall be

described in the revised methodology of connection fees, to be decided by the ERO.


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Some of the projects which the TDP 2012-2021 had scheduled for the northern part of the

transmission network have been postponed in time, due to the current situation of that part

of the Republic of Kosovo.

The following are projects which were added as new projects, which were not part of the

TDP 2012-2021, as a result of displacing technical and commercial boundaries between

KOSTT and KEK-DSO:

- Second transformers at SS Skenderaj, SS Klina, SS Burimi and SS Berivojce

- Revitalization of 35 kV voltage equipment at SS Gjakova 1, SS Gjilani 1, SS Ferizaj 1, SS

Prishtina 2 and SS Lipjani

- Reserve transformer 40MVA, 110/10(20) kV

Projects of load support, which are not related to the transfer of fees and connection fee

methodology, and are not part of the TDP 2012-2021:

- SS Mitrovica 2

- Project Package SS Malisheva

- SS Prishtina 6 and

- SS Fushë Kosova

The rationale for projects presented and expected benefits from their implementation is

provided with technical descriptions of each project presented above.

The projects which are not part of the TDP 2013-2022, while being earlier listed in the TDP

2012-2021, are:

- New 110 kV line Rahovec-Theranda

- New 110 kV line: Peja 1- Deçan

- New 110 kV line: Peja 3- Mitrovica 2

- Revitalization of L 118/1 SS Prishtina 1- SS Kosova A Line

- Revitalization of SS Klina and SS Lipjani (110 kV level)

The first project, the 110 kV line Rahovec -Theranda is incorporated with the SS Malisheva

Project Package. In this case, KOSTT shall require a derogation from the ERO, in terms of


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N-1 criterion for supply of Rahovec, which is to operate in a radial manner, until the

Malisheva project goes into function.

The second project, the 110 kV line Peja 1- Deçan, is not in the list as a result of connection

of 35 MW HPP “Deçani” with the 110 kV busbars at SS Deçan. This injected power reduces

the load flows in that part of the network, and for this reason, the project is rescheduled for

after 2022.

The project New 110 kV Line Peja 3- Mitrovica 2 is postponed beyond the 2013-2022

period, and it remains optional, the initiation of which shall depend on development of

industrial demand in Mitrovicë.

The project of revitalization of 110 kV Line SS Prishtina 1- SS Kosova A, is eliminated as a

result of influence of SS Prishtina 6, SS Prishtina 7 and SS Fushë Kosova in reducing load

flows in 110 kV lines supplying substations SS Prishtina 1, 2 and 3.

The SS Klina and SS Lipjan revitalization projects have been postponed for after 2013-2022,

due to a reduction in investment costs, thereby considering that their operations until <40

years of age may be economically reasonable, but always in due account of the level of

security of supply.

Also, the project of implementing changes to the SCADA/EMS is a new project, which

appears as necessary after the implementation of changes in the network configuration.


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6. TRANSMISSION NETWORK PERFORMANCE ANALYSIS

6.1. Description of the network model

Transmission network planning begins with creating basic mathematical model which

corresponds to network situation at the end of 2012 using technical data elements that

comprise the Power System. The parameters necessary for creating basic mathematical

model include:

- Electrical parameters of existing generators

- Electrical parameters of 400 kV , 220 kV and 110 kV lines

- Electrical transformer parameters, without including the 110/35/10 kV and 110/10 kV

transformers

- The maximum active and reactive power during winter and summer season in the points of distribution

and other expendable points.

- Common power flow in border lines

- Normal configuration of the transmission network.

Simulations and technical analysis of system performance in different periods have been

conducted with the help of software package PSS/E 32. This applicable software for the

planning processes of transmission networks is used in most countries of South-East

Europe, but also in many European countries and the world.

Iterative method (recurring), "Full Newton Raphson” is used to calculate the power flows,

while in calculating the security network criteria is used the module ACA " AC Contingency

Solution "which is integrated into the PSS/E.

For the purpose of calculating the analysis of short circuits to the system nodes, and

disconnection ability of the breakers for voltage level: 400 kV , 220 kV and 110 kV a more

complex model was used, which includes the entire region of South-East Europe, model

which contains the order parameters of positive, negative and nular elements of the network.

To calculate the short circuit currents in the transmission network are implemented the

method of calculation according to the IEC 60909 standard.


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Power System is analyzed for the most unfavorable conditions during the maximum load

on the network. Operating conditions and system performance depends on network

configuration, interconnection flows and connection of existing generators.

The analyzed performance of the current network has identified the network sections which

do not comply with technical requirements and the needs for reinforcement in appropriate

time sequences, in correlation with the planned development of the system load.

6.1.1. Transformation capacities; Q4-2012

Transformation capacities of the transmission network, managed by KOSTT, are installed at

substations 400/220 kV , 400/110 kV and 220/110 kV , 220/X kV and 110/X kV.

The largest transformation capacity is installed at SS Kosova B 400/220 kV. At this

substation, there are three auto-transformers installed with a nominal load of 400MVA. The

total transformation capacity of this substation is 3*400 = 1200MVA.

- At SS Peja 3, 400/110 kV, only one auto-transformer of nominal load of 300MVA is

installed. In SS Ferizaj 2 400/110 kV also, an automatic transformer with nominal

power of 300 MVA was installed.

- At SS Kosova A, 220/110 kV, three AT-s of nominal load of 150 MVA are installed,

with a total transformation capacity of 450MVA.

- At SS Prishtina 4, 220/110 kV, three AT-s of nominal load of 150 MVA are

installed, with a total transformation capacity of 450MVA.

- At SS Prizreni 2, 220/110 kV, there are three automatic transformers with nominal

power 150 MVA, with a total capacity of 450MVA.

- Whereas, substations 110/x kV and 220/x kV have an installed capacity of 1788. 5

MVA (without Trepça, Sharri and Ujmani).

Table 6-2 shows transformation capacities of the transmission network in Kosovo, as per

network configuration Q4-2011.


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Tab. 6-1 Transformation capacities at transmission network; Q4-2012

Total transformation capacities for the current year 2012 are 4938. 5 MVA. This increase of

the transformation capacity comes as a result of KOSTT’s ownership of all 110/35/10(20)

kV and 220/35/10 kV substations.

Distribution transformers do not include transformers in Trepça, Ferronikeli, Ujmani dhe

Sharri, which are not part of KOSTT assets.

Direct load supply at 35 kV and 10 kV levels is realized with transformation capacities with

400/110 kV, 220/110 kV, 220/35/10 kV and 110/35/10(20) kV, with a total capacity of

3738. 5 MVA.

6.1.2. The current load exchange capacity with neighboring countries

The maximum capacity of load exchange with neighbors (at natural line power) with high

voltage transmission lines is 1740 MW. At 400 kV lines, the existing cross border

transmission capacity is around 1500 MW (3x500 MW), while at the 220 kV level, some

other 240 MW are added (120 MW line with Albania, and 120 MW line with Krusevac,

Serbia).

ATR- Q4 2012 Number Total Transforming Capacity (MVA)

400/220 kV 3 1200 SS KOSOVA B

400/110 kV 1 300 SS PEJA 3 1 300 SS FERIZAJ 2

220/100 kV SS KOSOVA A 3 450 SS PRIZRENI 2 3 450 SS PRISHTINA 4 3 450

110/10 kV & 110/35 kV

49 1708.5

220/10/35 kV & 220/10kV

2 80

Total 65 4938.5


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NTC3 (Net transfer capacity) of interconnection lines in Kosovo is smaller than their natural

power, and it largely depends on the regional electricity balance in neighboring countries,

and from limitations to the regional horizontal network, which may appear in various

operational regimes. The table 6-2 shows the current capacities of interconnection lines as

per their natural power (P), average NTC and nominal thermal power (Sterm) [10]

Table 6-2. Current interconnection line capacities

The simultaneous interconnection transmission capacity (KNTI) is different from NTC, and

is calculated for two cases:

- When the electro-energy system simultaneously imports through all interconnections (at different time

periods), until a first limitation at the horizontal network appears for the importing country and

exporting countries (for the N-1 criterion).

3 NTC – means max total electricity power exchange between two control areas, compatible to security

standards applicable in all regulatory areas, and in due consideration of technical uncertainties of the network

condition (definition from the ENTSO-E guideline).

Niveli Fuqia natyrore Termike NTC

[kV] [MW] [MVA] [MW]

Kosovë - Serbi 600

NS Kosova B- NS Nish 400 500 1317

NS Podujeva - NS Krushevc 220 120 300

Kosovë - Maqedoni 400*

NS Ferizaj 2 - NS Shkupi 5 400 500 1317

Kosovë - Mali I Zi 400

NS Peja 2 - NS Ribarevinë 400 500 1317

Kosovë - Shqiperi 210*

NS Prizreni 2 - Fierza 220 120 300

* Nga https://www.entsoe.eu/fileadmin/user_upload/_library/ntc/archive/NTC-Values-Winter-2010-2011.pdf

SISTEMET DHE LINJAT

INTERKONEKTIVE


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- When the power system simultaneously imports through all interconnections (at different time

periods), until a first limitation at the horizontal network appears for the importing country and

exporting countries (for the N-1 criterion).

Calculation is rendered by the PSS/E software, based on long term demand and generation

forecasts for the regional countries, correlated with regional transmission system

development plans [8]. Natural flows at interconnection lines are flows defined by system

impedance, generation location and loads in case when individual systems are balanced (no

exchange). Natural flows are amongst key factors affecting various capacities of

interconnection for imports and exports.

The Simultaneous Interconnection Transmission Capacity is not calculated as an amount of

Net Transfer Capacity (NTC), and as such, it is much smaller4.

Currently, the KNTI of the transmission system in Kosovo is approximately 900MW for

power imports, and 1000MW for power exports. Considering the electricity balance, it may

be considered that current interconnection capacities are rather large, and allow for any

exchange program for the needs of the power system in Kosovo.

In order to ensure effective access to the transmission network and implicitly market

infrastructure for cross-border transactions, is developed regulations 1228/2003/EC which

sets out the principles for congestions managing. In this case, it has become clear that

interconnection lines congestions should be selected on the basis of market orientation and

non-discriminatory methodology. The allocation of capacity currently based on the

calculation of NTC, on the interconnection lines between TSOs. The experience of recent

years has shown that cross-border capacity allocation method based on the market can lead

to inefficient use of interconnection capacity, if not taken into account the real power flows

properly. Allocation based on power flows, now is used by several TSO in Europe.

In general, capacity allocation based on power flows presents a method which applies to

large group of TSOs. This means that bids for energy and relevant cross-border capacities

are optimized by a centralized entity that takes care of the actual allocation "Coordinating

allocation Office." In capacity allocation mechanism based on power flows, commercial

4ENTSO/E Raport: System Adekuacy Forecast 2009-2020


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transactions are not limited to interconnections where they have been reported, but they are

converted into the physical flow of power using simplified models in order to assess the

impact of flows in other interconnections, and to assess the overall safety of the

transmission system which includes the entire TSO-s group.

The expected advantages from the establishment of the "Office for coordinating allocation"

using coordinated sales based on the power flow are:

optimal use of existing interconnection

high level of system security

Facilitate regional market activities due to the efficient use of the transmission

network and the establishment of cross-border transactions

Increasing transparency between the parties involved.

Promote investment in infrastructure.

6.2. Analysis of the transmission network condition as per topology Q4-2012

Investments made in the transmission network during 2009-2012 have had an effect in

improving the operational performance of the transmission system. Current ongoing

projects, and those expected to be completed by the end of 2012, will enhance the network

even further towards compliance with the technical requirements as per Grid Code. Figures

6-3, 6-4 and 6-5 show Kosovo’s power system, as per network topology Q4-2012. Figure 6-4

shows power flows and voltage levels in the Power System in PSS/E.

6.2.1. N-security criterion analysis

The system was analyzed for a gross max load of 1170 MW, with all elements (lines,

transformers, load) at operation. In this case, power flows were monitored, together with the

level of voltage at bus bars, and level of load on 400 kV, 220 kV and 110 kV lines; and in

auto-transformers 400/220 kV, 400/110 kV and 220/110 kV, and after the transfer of 110

kV assets from KEK-DSO to KOSTT also in the 110/35 kV and 110/10(20) kV

transformers. Simulation results have not identified any overloaded elements. The maximum


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capacity of internal transmission network, as per technical security criterion N for the end of

2012 is around 1480MW. This means that the transmission system can supply a gross load of

1480MW, while fulfilling the N-security criterion. If one refers to the forecasted maximum

load, there is a sufficient security margin, approx. 26. 5% (310 MW).

6.2.2. N – 1 security criteria analysis

The system performance was analyzed in terms of the N-1 security criterion, thereby

monitoring line and transformation loads, and the level of voltage at bus bars when a critical

element (transformer, line, cable) fails. Table 6-3 presents the lines which do not fulfill the

N-1 criterion, the outage of which causes deviation of load or voltage, beyond the limits

allowed by the Grid Code.

Table 6-3. Lines falling out of N-1 criterion, as per network configurationQ4:2012

In addition, critical outages are also associated with the line SS Drenas –SS Prizren 2, but

this is only eliminated if we import 100 MW or more from Fierza.

Critical failures numbered 1 and 2 will be eliminated if the line 110 kV SS Prizren 2-SS

Prizren 1 with a length of 3. 2 km, is converted into a dual line.

Critical failures 3 and 4 will be eliminated with the completion of the project of line

allocation L1806 from Gjakova 2 to Gjakova 1.


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In terms of transformation, there are further restrictions to the fulfillment of N-1 criterion.

Table 6-4 shows substations which do not fulfill the N-1 criterion.

Table 6-4. Auto-transformers falling out of N-1 criterion (Q4:2012)

Computer analysis (simulations in PSS/E in the system model) have shown that currently

the transmission network can fulfill the N-1 criterion for loads smaller than 1080 MW.

Figure 6-1 presents development of N and N-1 capacities of the (internal) network, in

relation to the seasonal load for the period Q1/2011-Q4/2012.

Figure 6-1 Development of internal transmission network capacities from Q1-2011 to Q4-2012.

Capacity /N (MW) Capacity /N-1 (MW)Peak load (MW)


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6.2.3. Voltage profile and losses

Creation of powerful nodes at SS Peja 3 and SS Ferizaj 2, and construction of 110 kV lines

and their reinforcement has made possible the situation that in normal operation conditions

of the transmission system (at maximum load), the level of voltage as per configuration Q4-

2012 is within allowed limits as per Grid Code. Figure 6-2 shows voltage profiles for two

different network topologies in 2011 and 2012. The chart presents that the voltage levels at

all nodes are within limits allowed by the Grid Code. One may observe the impact of entry

into operation of 100 kV line SS Ferizaj 2 – SS Gjilan 5, which reflects in a considerable

increase of voltage level at 110 kV nodes of some substations in the region of Gjilan

connected to the substation. In terms of fulfillment of the N-1 security criterion in terms of

voltage, tables 6-3 and 6-4 present the critical failures which cause a decline of voltage levels

under the limit allowed by Grid Code.

Fig 6-2. Comparison of voltage profile at 110 by two network topologies,2011 and 2012

The system was analyzed also in terms of load loss in maximum load, while the computer

calculation results are presented with the table 6-5. Losses were calculated specifically in lines

and transformers, as per level of voltage. Calculated load losses in peak load are based on

ideal resistance and inductivity of elements modeled at PSS/E, and do not reflect real losses,

which are dependent on other factors which cannot be modeled, such as: resistance of

contact of high voltage equipment, resistance of connection bridges in line conductors,

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114

116

118

120

122

124

U(k

V)

Topology_2012_P=1170 MW Topology_2011_P=1150 MW


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crown effect, impact of temperature change at Ohm resistance, etc. Nevertheless, the results

gained provide important comparisons showing the trend of loss development at the

function of load changes and network capacity. Grid load losses for various years do not

match with energy losses during a year, since in the majority of cases, grid reinforcements

take place in the fourth quarter of a year, while the effects at the volume of energy losses in

the network can only be recorded in the next year, after relevant reinforcements are made.

Tab. 6-5. Active and reactive power losses at maximum load (Q4-2012)

In terms of active power, the largest losses are caused at transmission lines (76%), where

losses at 110 kV lines dominate with a percentage of 66. 7% in comparison to total loss. In

comparison to peak losses in the previous year 2011 (29MW), current year losses have

marked an increase, 15% higher, which can be justified by the fact that 10/35/10(20) kV/

kV and 220/35/10(20) kV/kV distribution transformers have also been added in the

transmission network, and the peak load increased simultaneously with the network capacity

improvement. Reactive power losses are caused mainly at power transformers, while total

lines are rather close to reactive compensation. Losses of reactive power are greater than the

distribution transformers (74. 8 MVAr).


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KOSOVO POWER SYSTEM 400/220/110 kV

Fig. 6-3 Single pole scheme, Kosovo power system, network topology Q4-2012


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Fig. 6-4 Modell of the PSS/E of the Kosovo Power System by network topology Q4-2012


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Fig. 6-5 Kosovo Power System by network topology Q4-2012


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6.3. Analysis of the transmission network condition by topology- 2018

During 2018, rather important projects are due to complete, thereby influencing directly the

improvement of the operational performance of the transmission system. In the period

2013-2018, we expect to have operational the following projects

- SS Prishtina 7 110/10(20) kV

- SS Mitrovica 110/10(20) kV

- Interconnection line 400 kV SS Kosova B – SS Tirana 2

- Hydropower Plant “Lumi Deçani” 35 MW

- Second Auto-Transfomer 300MVA, in SS Peja 3, 400/110 kV

- Second Auto-Transfomer 300MVA, in SS Ferizaj 2, 400/110 kV

- New 110 kV line SS Peja 3- SS Peja 1

- Revitalization of the line L155/2 and L163

- SS Dragashi and line 110 kV SS Kukës-SS Dragash- SS Prizren 2

- SS Malisheva and line 110 kV SS Rahovec -SS Malisheva– SS Theranda

- SS Prishtina 6 110/10(20) kV

- SS Fushë Kosova 110/10(20) kV

- Revitalization of the line110 kV: L126/2 SS Peja 2- SS Deçan

Gross maximal load in 2018 is forecasted to be 1365MW. Figure 6-9, 6-10 and 6-11is shown

in Kosovo’s Power System, by network topology Q4-2018. Figure 6-10 shows the power

flows and voltages in the Power System in PSS/E.

6.3.1. N-security criterion analysis

The system was analyzed for the maximum estimated gross load of 1365 MW, for the

network topology Q4-2018, with all elements (lines, transformers, load) in operation.

The simulation results have not identified any lines or transformers overloaded. The

maximal capacity of the internal transmission network, as per N-security criterion for the

end of 2018 will increase considerably compared to 2012, as a result of planned

reinforcements in the transmission network. Maximal capacity of the internal transmission


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network would revolve around the amount of 1850MW. This means that the transmission

system can supply a gross power of 1850 MW by the end of 2018, without any network

bottlenecks and under the allowed voltage level limits. Referring to the maximum estimated

load for 2018, there is a sufficient security margin, which circles around 34% (465 MW).

6.3.2. N-1 security criterion analysis

Implementation of planned projects until 2018 will result with a transmission system which

for the first time will fully meet the technical criteria required by the Grid Code, in terms of

security and quality of supply. From the fourth quarter of 2018, the transmission system will

fulfill the N-1 security criterion for lines (cables) and transformers, always referring to the

values outlined for the load in the next ten years. If the load forecast goes according to the

low scenario, the N-1 criterion will be fulfilled earlier.

Figure 6-6 shows N and N-1 capacity development of the (internal) network, in relation with

the seasonal load for the time period Q1:2013-Q4:2018

Capacity /N (MW) Peak load (MW) Capacity /N-1 (MW)

Figure 6-6 Internal transmission network capacity development, from Q1-2012 to Q4-2018.


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The voltage profile at all 110 kV voltage levels in the 2018 network topology should remain

within optimal limits in maximum load, as shown in the figure 6-7.

Fig. 6-7Voltage profile in 110 kV bus bars as per 2018 network topology

In operational regimes at summer loads in the system, higher voltage levels are recorded,

especially at 400 and 220 kV horizontal grids, as shown in the figure 6-9. The reason for

such an increase in voltage is development of the 400 kV network capacities in the region

influencing our system; construction of a 239km long line SS Kosova B- SS Tirana 2, which

in minimum load regimes should inject around 75MVAr of capacitative reactive power in SS

Kosovo B bus bars. In this case, the installation of an inductive reactor 120MVAr at SS

Tirana 2 (220kV bus bars) is considered.

The control of voltage level at 400kV bus bars is almost negligible, by undertaking

operational measures within the relatively small power system of Kosovo, while the voltage

level at 220 kV bus bars is partially controllable, by making limited modifications of the

network topology (opening of the SS Fierza – SS Prizren 2 line, disconnection of a

transformer at SS Kosova B etc). Over-voltage levels at 110kV level can be managed easily,

since the 110 kV network topology can be modified as per certain modes, with a view of

avoiding line overcompensation. The only technical possibility of controlling overloads on

transmission grids is installation of an inductive static reactor 100MVAr at SS Kosova B (at

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U(k

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substations 110 kV

Profile UUmax,UminUnominal


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220 kV bus bars). Due to high uncertainty of network developments in the region, the

voltage level at the horizontal network (inside and outside the system) will be monitored

carefully, so as to ensure a timely decision on planning installation of a 100 MVAr reactor at

SS Kosova B.

Fig. 6-8 Voltage level at 400kV and 220kV bus bars in summer minimum load regimes.

Active power losses will be reduced at 110 kV lines, while at 400 kV lines there will be an

increase of losses, as a result of construction of the 400 kV line SS Kosova B – SS Tirana 2,

and the increased transit flux in the transmission network. The active power losses will

increase in comparison to 2012, while reactive power losses will decrease in comparison to

2012. The following table shows total losses at transmission network, and loss percentages as

per voltage level and type of element.

234.5kV

412.8kV 411.6kV 412kV

234.3kV 233.4kV

230.3kV

233.4kV 233.8kV

0.98

1

1.02

1.04

1.06

1.08

1.1

1.12

(P.U

)

Voltage profile Unominal Umax Uextrem


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Tab. 6-6. Active and reactive power losses in maximum load (2018)


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Fig. 6-9 Single pole scheme of Kosovo power system, network topology 2018


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Fig. 6-10 Model of the Kosovo Power System in PSS/E according to network topology 2018


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Figure 6-11. Kosovo Power system according to network topology 2018


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6.4. Analysis of the transmission network condition, topology - 2022

The operational performance of the transmission system was analyzed for 2022, modeled in

PSS/E by integrating all planned projects for the next 10 years. As per a list of projects

selected by a computer analysis determination, a considerable number of important projects

of transmission network reinforcement is planned for implementation for the time period

2019-2022 such as the following:

- Revitalization of the line SS Prizren 1 – SS Prizren 3

- New line 110 kV SS Prizren 1- SS Prizren 2

- Revitalization of the line L163 SS Kosova A- SS Bardhi - SS Mitrovica 2- SS Vallaq

- New line 110 kV SS Peja 3- HC Ujmani

- Revitalization of the line110 kV , L115/2

- Project Package 400 kV ring Gjakova - Prizren - Ferizaj (phase I)

Figures 6-15, 6-16and 6-17show Kosovo’s Power System according to network topology of

Q4-2022. Figure 6-16shows the power flows and voltages of the Power System in PSS/E.

6.4.1. N security criterion analysis

The system was analyzed with 1000 MW of new generation capacity connected to SS

Kosova B and decommissioning of the TPP Kosovo A, referring to the conservative

generation development scenario as per document “Generation Adequacy 2013-2022”.

The system was modeled to a gross load of 1494 MW as forecasted for 2022. The

construction of SS Prizren 4, 400/110kV and creation of a 400kV ring, should ultimately

bring the transmission network to a condition conducive to further support for the load and

development of large generation capacities, both conventional and renewable. As presented

by the Fichner study, the new 400 kV network topology will enable the sectioning of load

groups connected at 110 kV network, and enhancement of operational security of the

transmission network, by establishing reserve disconnection capacities. The internal network

capacity will have attained the amount of 2100MW with a 40. 5% (606MW) security margin


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in relation to the maximum load for 2022. The figure 6-11 presents a horizontal scheme of

the transmission network, modeled after the regional network (SECI_2020_PSS/E). The

model shows the load flows for certain regimes of regional exchange. The ring configuration

allows for the creation of four consumption groups to be supplied by main transmission

substations.

Fig. 6-12 Horizontal network of transmission system, after development of 400 kV ring - topology

2022

6.4.2. N-1 security criterion analysis

The 2022 network topology transmission system does not identify any lines or transformers,

the outage of which would create any overload or underload in other parts of the network.

Such a network topology allows for a full compliance with the N-1 security criterion up to

the consumption rate of 1500MW. The creation of a 400 kV ring, and creation of four


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consumption supply groups, all create higher flexibility and operation security of the system.

The failure of any single 400 kV line would not influence the security of supply for

consumption and regional exchange. The N-1 criterion is fulfilled both for interconnection

lines and internal lines.

Development of internal network capacities for the period 2018-2022 is presented with the

figure 6-13.

Capacity /N (MW) Peak load (MW) Capacity /N-1 (MW)

Fig. 6-13 Internal transmission network capacity of transmission 2018-2022.


The reconfiguration of the 110 kV network, by creation of four supply groups I- Peja 3, II-

Kosova A & Prishtina 4, III- Ferizaj 2 and IV-Prizreni 2&4, creates an almost maximal

optimization conditions for load flows, reflected into an ideal voltage profile at all bus bars

400, 220 and 110kV during the winter consumption.


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Figure 6-14 shows the voltage profile for 110kV bus bars.

Fig. 6-14 Voltage profile in 110 kV bus bars as per network topology for 2022

MW-expressed network active power losses will be higher than 2018, as a result of growing

consumption. As per computer calculations (Table 6-7), losses of active power in peak load

1494MW will be 40. 5 MW, from which 77. 8% are caused by lines, where line losses

dominate 110kV (54. 3%).

In terms of reactive power in the transmission system, the influence of 400 kV ring is rather

present. Lines inject a total reactive power of 161 MVAr (capacitative) into the network,

while on the other hand transformers can absorb a reactive power rate or approx 225.5

MVAr (inductive), which means that only 73. 5 MVAr are counted as reactive power losses

caused by the transmission network. The reactive side of consumption is to be covered by

domestic generation sources.

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Fer

2

Fer

1

Ber

iv

Vush

i 2

Bar

dh

Deç

Dra

Gja

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Sh

arri

Gjil

ani 5

Ujm

ani

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mi

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i K

lina

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eja

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a 1

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Pz

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z T

hez

Tre

pz

Ko

s A

Val

l

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Vo

ltag

e [

kV

]

Voltage profile Unominal Umax Umin


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Tab. 6-7. Active and reactive power losses in maximum load (2022)


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Fig. 6-15 Single-pole scheme of the Kosovo power system, network topology 2022



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Fig. 6-16 Model of the Kosovo Power System in PSS/E according to network topology 2022


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Figure 6-17 Kosovo Power System by network topology 2022


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6.5. General conclusion

The Kosovo transmission system must develop in a manner of allowing for a secure, reliable

and qualitative supply of consumption, pursuant to technical requirements of the Grid Code

and the operation manual of ENTSO/E. An adequate and sustainable development of the

transmission system provides for favorable conditions of development of conventional and

renewable generation capacities. Appropriate long term planning for transmission system

development is essential to meeting above-mentioned requirements. The Transmission

Development Plan 2013-2022 has identified medium and long term needs for infrastructure

projects necessary for the enhancement and maintenance of the operational performance of the

system, in relation to development in consumption, generation and regional markets of energy.

The TDP 2013-2022 sets forth the development priorities broken down by category and

implementation timelines. The full realization of transmission development plans is challenging

to the most developed countries. Difficulties in accessing property, global economic crisis, lack

of financial resources, social implications, are some of the factors which may slow or prevent

the realization of projects which are necessary to be taken into account by planning engineers.

If one would refer to development of KOSTT in the last 5 years, it may be considered that

development objectives have largely been realized thanks to financial support of the Kosovo

Budget and international donors. Positive impacts of projects completed and those ongoing

have been analyzed in the previous development plan, while the following are general

comments on new development projects presented in the TDP 2013-2022.

Developments in the last 5 years of the transmission system have created conditions for

KOSTT membership to ENTSO/E. Regarding policies arising from ENTSO/E Operation

Handbook which relates with technical requirements to be fulfilled each TSO, KOSTT with

recent investments, increasing the transmission capacity, security and reliability of the system as

well as development modern systems for measurement, monitoring and control, is in the same

position or better than some of the TSO-s in the region which are already members of the

ENTSO/E. With development of the secondary control project which represents one of the

main technical requirements for membership in the ENTSO/E, KOSTT will be fully ready for

membership.


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6.5.1. Network capacity development

The implementation of projects identified by the TDP 2013-2022 will enable a consistent

enhancement of internal network capacities, which in turn would render conducive to supply

consumption. Reinforcement at key nodes at SS Peja 3, SS Ferizaj 2 and SS Prizren 4, 400 kV

and 110 kV network reconfiguration with the development of new 110 kV lines, are the key

factors to foster development of transmission network capacities. The figure 6-18 shows a chart

of development of internal network capacities in relation to load development for the next 10

years, in two scenarios of peak development.

Fig. 6-18. Development of internal network capacities in relation to load development for the next 10

years

In the next ten year period, the horizontal network will also be subject to capacity

enhancement, as a result of development of the new 400 kV interconnection line SS Kosova B

– SS Tirana 2, and construction of the 400 kV ring in Kosovo. The capacity of transmission

network interconnection lines in Kosovo will be much higher than the import margin, or

possibilities of electricity export available to our country for the next 10 years, even in due

consideration of a considerable volume of transit flows (through our network) for the regional

countries. However, on the other hand, restrictions are announced in the regional network,

which could limit high imports. In most cases, capacities presented by TSO-s of the region,

particularly by EMS, are considerably lower than the reality. Figure 6-16 provides indicative

Capacity /N (MW) Peak load (MW) High peak load (MW)

Security margin


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values of simultaneous interconnection capacity for export and import, calculated in a regional

model. The estimated capacities take into consideration the N-1 criterion for the whole

horizontal network of regional transmission systems.

When referring to planned generation development in Kosovo, the horizontal network will be

able to accommodate considerable generation capacities in full compliance with technical

requirements of ENTSO/E. In case of construction of a second 400 kV line SS Kosova B –

SS Skopje, interconnection capacities would be considerably higher. This project remains

optional, and its advancement will largely depend on the changes of transit flows to

Southeastern European countries, and the size of generation capacities to be installed in

Kosovo.

Fig. 6-19 Simultaneous interconnection capacity development 2013-2022

6.5.2. N-1 security criterion

If one was to review the situation in the network before 2009, the N-1 security criterion would

not be compliant even in summer consumption, while in normal operation conditions, the

network would be subject to overloads which were managed by reducing load. In reference to

the current situation (2012), the network condition has changed largely for the better, in which

case the network does not display any bottleneck, while the N-1 security criterion is not

complied with only at 5% of the annual time, excluding radial supplies of Rahovec and Lipjan.

1000

1500 1500

-900

-1400 -1400-1600

-1400

-1200

-1000

-800

-600

-400

-200

0

200

400

600

800

1000

1200

1400

1600

1800

2013 2014 2015 2016 2017 2018 2019 2020 2021 2022

KNTI Export [MW] KNTI Import [MW]MW


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Full implementation of the N-1 security criterion requires considerable investment. If we refer

to development processes planned for the next 10 years, the security criterion will be fully

complied with only after 2018, while until then, the criterion will be very close to completion.

The figure 6-20 shows the ability of the network to fulfill the N-1 security criterion, in a relation

with the maximum load for the next 10 years, for two load scenarios. It is clear from the Figure

that the N-1 criterion will not be fulfilled even after 2018 if we take as reference the high load

increase scenario.

Capacity /N -1(MW) Peak load (MW) High peak load (MW)

Fig. 6-20. N-1 capacity development of the transmission network 2013-2022

6.5.3. Quality of supply and efficiency

Not long ago, a considerable part of the transmission network could not provide quality supply

in winter peaks due to the poor network, large active and reactive power losses. All this resulted

in rather low voltage levels at the 110 kV level, especially in areas remote to generation sources.

On the other hand, the amount of energy undelivered to consumption, as a result of restrictions

in the transmission network, was rather high. Reinforcements to the network, especially after

2008, have created the conditions for a quality supply of consumption and an extraordinary

reduction of power losses in the grid. The voltage level was stabilized after the commissioning

of the Peja 3 project, while with further investments, the operational efficiency of the network

and quality of supply were enhanced to a satisfactory level. The planned reinforcement in the


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next 10 years will allow for a further enhancement of quality of supply and efficiency, but also

maintenance, pursuant to technical requirements of the Grid Code.

7. FAULT CURRENTS IN THE TRANSMISSION NETWORK

7.1. Introduction

This chapter examines the problem level of fault currents in all bus bars of 400 kV, 220 kV and

110 kV voltage level. Review of fault currents or three phases and one phase to ground short

circuit level was made for periods in relation to the planned developments in transmission

network and the overall Kosovo Power System.

7.2. Calculation of fault currents level

Kosovo Power System is strongly interconnected to regional transmission network 400 kV and

220 kV . Relevant supplies of fault currents which are characterized by serious impact on

system security are concentrated in two main substations of the system: SS Kosovo B and SS

Kosovo A. All existing TP plants are connected in the two substations. The objective of the

study of short circuits is assessment of the impact of fault currents in the security of the system.

Fault currents in 400 kV, 220 kV and 110 kV bus bars will be calculated in accordance with

Policy 3 of the Operation Handbook of ENTSO-E.

The essential objective of this study is to identify the bus bars in which the level of fault

currents exceeds breaking capacities of the existing breaker and determination of security

margin of all installed breakers or those that will be installed in the transmission system in

Kosovo.

7.2.1. Mathematical model, calculation methodology and applied software

In order to determine the maximum fault currents in transmission system of Kosovo and the

impact of neighboring systems in these currents, in study was used regional model which

include 13 models of integrated Power System of the countries of South-Eastern Europe. For

this analysis is also used software PSS/E 32. Part of the network which is interconnected with


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this model it’s equal to the Teveneni network (method for simulations of models in the case of

large networks).

Calculation methodology is based on the IEC 90609 standard. Maximum effective value of the

sub-transient component of the total fault currents three-phase and one-phase with ground, is

applied to every bus bars of level 400 kV, 220 kV and 110 kV. Different from the previous

plan, after the transfer of 110 kV assets, two and tri layer 110/x kV transformers were

incorporated in computer models in PSS/E. In this case the generators are equaled to their sub-

transient reactance X "d. The time of 100ms is considered as the time of fault elimination.

Based on IEC 90609 standard, calculations are made for no load operation, while the initial

conditions of the equaled network voltage of the Tevenen is taken as 1.1Un.

Idc Dc component of fault current

Higher limit

Lower limit

Current

Time

Ik” = Effective value of the fault currents

ip = The initial amplitude of the fault currents

Ik= Continual fault currents

idc = Dc component of the fault currents

A = Initial value of the dc component of idc

Fig 7-1 Form of the fault currents and its components


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7.2.2. Features of the power circuits of the transmission network

In the transmission system currently in the existing substations of KOSTT are installed

different types of circuit breakers in terms of producers. While in terms of types of dielectrical

medium for extinguish electric arch are installed two types of breakers:

- Oil circuits and

- Gas circuits SF6

The old generation of the breakers have usually used oil as a dielectric medium for extinguish

the arch, while new generations of breakers use SF6 gas with a dielectric characteristic and

much better durability.

Breakers with SF6 medium for arch extinguish represent necessary standard of breakers for

installation in transmission network. Also this kind of breaker has general features significantly

better than oil breakers, as in electro-mechanical stability during the process of normal

connections and disconnection, or the occurrence of fault currents.

KOSTT systematically is replacing the oil breakers with the new breakers within the re-

vitalizing projects of the existing substations. Disconnection capacity of circuit breakers is

different starting from 16. 5 kA, 18. 3 kA, 23 kA, 31. 5 kA and 40 kA. The safety margin of the

breakers and other high voltage equipments is estimated by recognizing the level of faults

currents failures in a long-term domain that can occur in all substations and compared with the

level of disconnection capacities of the breakers.

7.2.3. Results of the calculated fault currents

Based on IEC 60909 standard, are calculated three-phase and one-phase to ground short circuit

for voltage levels 400 kV, 220 kV and 110 kV of the transmission network. Calculation of

currents is made in computer models in relation to the project development under the network

configuration: 2012, 2018 and 2022.

In Chapter 8, in a more general manner, we have presented the effects of installing new

generators to increase the value of fault currents in the domain of the second five year planning

period, starting from the lowest scenario development of generating units of PP New Kosovo,

HPP Zhuri, and the HPP “Deçan River” connected in SS Deçan.


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7.2.4. Assessments of the calculated fault currents in busbars 400 kV, 220 kV

and 110 kV (2012)

Results of simulation of three-phase and one-phase fault currents with ground for network

configuration according to the latest situation in 2012 based on the IEC 60909 standards is

presented in Figure 7. 2.

The results of computer calculations in PSS/E show greater level of short circuit power in two

main substations, SS Kosovo A and SS Kosovo B, which are very close to generating resources

and supplies from the powerful interconnection of 400 kV .

At 220 kV busbars at SS Kosovo A the one phase to ground short circuit at a value of 27 kA

represents the largest electricity transmission network. Also in the SS Kosovo B at the both

levels of voltage the one phase to ground short circuit are relatively large at 20. 9kA (at 400 kV)

and 26 kA (220 kV). In all other parts of the network, distancing from generator sources, three-

phase short circuit current dominates over the single-phase. All 110 kV substations near SS

Kosovo A (Prishtina area), are characterized with large fault currents. Results of calculating the

level of fault currents lead to the following conclusions:

- 400kV , 220kV and 110kV breakers installed in the transmission network have e sufficient security

margin (>20%). Their disconnection capacity towards fault currents level is within the limits allowed

under the IEC standards for the high voltage disconnection equipments.

Plans for re-vitalizing of substations SS Peja 1, SS Gjakova 1 etc will help increase the safety

margin of these substations, which have very old breakers installed that do not guarantee the

stated nominal stability.


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Ik3-three phase fault Ik1-one phase to earth faultFa

ult

cu

rren

t [k

A]

Fig. 7-2 Chart of three and single phase earthed fault currents, for the current network topology

7.2.5. Assessments of the calculated fault currents in busbars 35 kV and 10 kV

After the transfer of distribution transformers 110/X kV from KEK-DSO in KOSTT, two and

three-layer transformer models were transferred to calculate short circuits in the computer

model, for the busbars 10 kV and 35 kV . Transformer fields and owner consumption fields are

now part of the KOSTT infrastructure. Calculation of fault currents have identified breakers

which have no security margin and their operation may risk the security of supply. Table 8-

1shows values of three-phased short circuit current values for busbars 10 kV and35 kV for the

case when transformers are not working in parallel in the medium voltage side, as it is the

practice.

Single-phase short circuit currents with grounding in distribution systems are usually limited

through Xg reactance or Omic resistance Rg. According to the Distribution Code, transformers

110/35 kV must ground their neutrals through the so-called Petersen reactance, which

represents and resonant impedance and are applied when there are long and numerous 35 kV

cables. In this case, single-phase short circuits with grounding are limited in the range 300-

400A.


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Transformer neutrals 110/10(20)kV are grounded through omic resistor of various resistances,

depending on the transformer power and desired value of single-phase short circuit limitation

with grounding. Usually single-phase fault currents with grounding are limited in the range 150-

300A.

The breakers’ security margin was determined from the calculations of three-phased fault

currents comparing with the disconnection breakers installed capacity in existing substations.

The data presented in Table 8-1identify three substations with inadequate dimensioning of

currents breakers.

Calculation results of the level of fault currents lead to the following conclusions:

- In SS Prishtina 1 and SS Prishtina 3, existing breakers of 10 kV level risk the security of supply, as

they have a negative security margin

- In SS Klina, the 10 kV transformer field breaker has the best dimensioning (25kA), but other

outgoing breakers 10 kV have a highly reduced margin. Breakdowns during nighttime when voltage

level may exceed 1. 1Un,may be a risk for the substation.

- Other substations have a sufficient security margin

- Installation of transformers 63MVA of voltage level 110/10 kV must be avoided due to high fault

currents in busbars 10 kV


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Table8-1 Calculations of three-phased short circuit current in busbars 35 kV and 10 kV

7.2.6. Assessments of the calculated fault currents (2018)

The development of the network and change of the configuration change affects the values of

fault currents. An input in raising fault currents should be given by the new interconnection line

400 kV SS Kosovo B – SS Tirana 2, which is expected to enter operation in 2015. Also

Substation Ik3

[kA] CB

[kA] Margin

Besiana 35kV 9.9 20 50.5% Besiana 10kV 24.2 31.5 23.2% Prishtina 1 35kV 9.5 16 40.6% Prishtina 1 10kV* 34.7 25 - 38.8% Prishtina 2 10kV 30 40 25.0% Prishtina 3 10kV* 23.1 20 - 15.5% Prishtina 5 23.1 31.5 26.7% Bardhi 35kV 14 25 44.0% Vushtrria 1 35kV 4.5 12 62.5% Vushtrria 2 10kV 16.4 25 34.4% Skenderaj 10kV 15.3 25 38.8% Vallaq 35kV 8 12 33.3% Burim 10kV 16.6 25 33.6% Peja 1 35kV 5.9 25 76.4% Peja 2 10kV 16 25 36.0% Deçan 10kV 15.3 20 23.5% Klinë 10kV 15.6 16 2.5% Gjakova 1 35kV 3.8 16 76.3% Gjakova 2 10kV 16.7 25 33.2% Rahovec 35 kV 4.6 20 77.0% Rahov ec 10kV 10.6 25 57.6% Prizren 1 35kV 4.6 16 71.3% Prizren 1 10kV 16.7 20 16.5% Prizren 3 10kV 17.2 20 14.0% Therandë 35kV 6.4 16 60.0% Therandë 10kV 16.4 25 34.4% Lipjan 35kV 4.9 25 80.4% Lipjan 10kV 17 25 32.0% Ferizaj 1 35 kV 4.8 15 68.0% Ferizaj 1 10kV 23.3 31.5 26.0% Viti 35kV 3.7 25 85.2% Gjilani 1 35kV 4.3 12 64.2% Gjilani 5 10kV 15.6 25 37.6% Berivojce 13.3 25 46.8%


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impedance reduction of 110 kV lines due to their reinforcement impacts the growth of fault

currents. Figure 7-3 shows the values of short circuit currents, three and single-phased earthed

connections in main substations.

Based on the plan for re-vitalization of substations in relation to the disconnection capacity of

high voltage equipment and values calculated for the fault currents in the system for

configuration 2018 can be concluded that:

- All circuit breakers installed in the transmission network and all high voltage equipment have

sufficient margins of safety(>20%).

Plans for re-vitalizing of substations SS Peja 1, SS Gjakova 1 etc will help increase the safety

margin of these substations, which have very old breakers installed that does not guarantee the

stated nominal stability.

Fig. 7-3 Chart of three and single phase earthed fault currents, for the 2018 network topology.

7.2.7. Assessments of the calculated fault currents (2022)

The 2022 model takes into account the development of new generation units based on the

conservation scenario of the Generation Adequacy Plan 2011-2020. In this model TPP Kosova

A is disconnected, and three units 3x300MW are modeled as shown in Figure 6-11. From

results presented in Figure 7-4, a notable increase is noticed in the level of fault currents as a

result of the construction of new generation capacities, and the construction of the ring 400 kV.

Ik3-three phase fault Ik1-one phase to earth fault

Fau

lt c

urr

ent

[kA

]


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At 220 kV bus bars at SS Kosovo B the one phase to ground short circuit at a value of 29. 3 kA

represents the largest electricity transmission network. In 220 kV busbars, there is a domination

of single-phased short circuit current with grounding with a 26. 8kA value. Because of the

decommissioning of TPP Kosovo A, the level of fault currents will be lowered if compared

with the calculated values from 2012 and 2018 models, the effects of construction of SS Prizren

4, 400/110 kV connected with the 400 kV ring, are also noticed in the region of Dukagjini.

Fault currents are notably higher in substations near SS Prizren than before construction.

If we compare the disconnection ability of fault breakers with the level of fault current level, we

reach the following conclusions

- All installed power breakers in the transmission network have a sufficient security margin. (20%).

- Installed power breakers in SS Kosova B and SS Kosova A and all high voltage equipment are not

risked by the construction of TPP New Kosova, 3x300MW. Their disconnection capacity 40kA allows

sufficient security margin.

Fig. 7-4 Chart of three and single phase earthed fault currents, for the current network topology2022.

8. ENVIRONMENTAL IMPACTS

8.1. Environmental protection

Continuous caution for environment will be part of the overall KOSTT Policy and engagement

of this police is addressed in the certification of KOSTT with ISO 14001:2004 Standard.

KOSTT Development Plan will take measures to prevent and correct any mistake that is

Ik3-three phase fault Ik1-one phase to earth fault

Fau

lt c

urr

ent

[kA

]


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referred to the environmental protection in accordance with the internal and external legal

bases. Negative impacts mainly include terms of the impact of electromagnetic fields (EMF),

noise and visual impact on the environment (more important effects).

It is a primary objective for KOSTT for the future to put particular attention to gaps, which can

directly or indirectly affect the health and wellbeing of the KOSTT staff, and certainly the

health and wellbeing of parties outside of KOSTT.

8.2. Environmental problems in the transmission system

One can say that the Environmental problems in the transmission system are divided into following:

- Environmental problems caused by the lines, and - Environmental problems caused by the substations

8.2.1. Environmental problems caused by the lines

Today when needed energy necessary for the development of our country, appeared in the

Development Plan, we need to adjust the priority of claims being aware of their impact on the

environment. Therefore we can say that the priority is set towards a necessary development of

electricity transmission of high voltage (during the above elaboration this need is reflected and

justified), not to eliminate the need to minimize the possible impacts on the environment.

Most of the lines pass through the agricultural areas, while a little less of those lines that pass on

the mountain ecosystems where their impact is not so expressed.

From the aspect of electromagnetic radiation, greater influence has the industrial frequency

electromagnetic fields. The research of harmful effects of this type of non-ionizing radiation on

man have not yet given the final answer, but it should be noted that nowadays there is a special

interest for the possible effects of electromagnetic fields on electrical equipment as well as on

the living creatures, especially on people. On the moment of the legal sanction of

electromagnetic impact this plan will take into consideration and will be subject to TDP's

implementation.


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We are in the phase of adequate recordings for most sensitive aspects of environment impact,

aiming to adapt to the requirements recommended by the WHO. We also have to monitor the

causes of faulty automatics actions, reduction of the signal-noise ratio in communication and

transmission equipment, and other important impacts, summarizing the necessary and required

data.

8.2.2. Environmental problems caused by the substations

Besides occupying the surfaces substations carry the biggest visual changes in their

surroundings, but in aesthetic terms do not affect significantly, since under the rules they

should be located outside residential areas. The continuous noise caused (transformers work) or

the non-continuous work (disconnection equipment/circuits), the most direct impact on the

environment of substations, and due to vegetation relief is rarely transferred to the residential

areas, but in the substations location is likely to have greater value than those allowed. This will

be determined soon, and adequate measures are likely planned and undertaken.

In modern equipment, breakers/disconnections include inert gas, hazardous for human health

of not used properly and sufficiently (timelines are specified and gas releases must be

sporadically measured), but have a undesirable impact in the ozone layer and with toxic

products in small concentrations, which are caused during the working process in equipment.

Having in mind that there are strict procedures in accordance with international rules, in the use

and maintenance of SF6 circuits, it is proposed that the implementation of SF6 technology, is

ensured after a period of time, when we consider the need to add gas, detectors issuing leaking

warning near the switch, followed by measurements of compensated amounts, and also through

adequate measurements, so that the risk index will be brought to minimum.

Large quantities of synthetic oils found in power transformers, while a little less in the high

voltage equipment. Having in mind that oils possess a high potential for environmental

pollution, adequate measures are taken, such as the construction of collecting pool and

protection for collections of any oil leakage. These pools at the same time are a kind of

prevention in cases of large failures likely to occur.

In the second half of 2012, we have received 28 facilities of SS 110 kV , for which we have

undertaken GAP analysis, which, with ToR, should be oriented towards appropriate


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improvements and, as we have acted in previous KOSTT SS, this is a perspective of objectives

in developments in environmental aspects in KOSTT, in terms of SS. Draft Pilot Project for an

Echo-analysis of the largest SS in KOSTT, “Kosova B” 400/220 kV will start its

implementation in 2013. With this Project we will also create an adequate and effective

assessment plan, in the perspective of other environmental assessments.

8.2.3. Caution on the other environmental impacts

At a time when the need for more and more energy is growing, the real impact on the

environment and aims for qualitative protection of this segment including this TDP that

supports the following:

- Reduction of emissions in water, air and land

- Increase of energy efficiency

- Enforcing preventive measures in order to reduce the number of accidents

- Addressing remains, particularly hazardous ones

- Possibility for recycling in many functional forms, including in indirect ways

- Development of systems for data collection and database (electronic forms)

- Reduction of parts and equipment that are outdated

- Follow-up of gaps in the Line system

- Drafting documentation for this Transmission segment

- Construction of dual lines, where there are possibilities to rationalize the use of surfaces and corridors

- In general, the improvement of corridor occupation for Transmission, where possible

All these are implemented in preliminarily planned time frames, such as:

- Reducing the damage done in the past

- Reduce the impact of ongoing activity in the relevant sector, and

- Prevention of pollution from activities in the future (e. g. EIA - Environmental Impact Assessment

and preventive measures in proper reduction)


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8.3. Environmental plans

In favor of the implementation of the requirements for environmental protection is the well

supported initiative in setting environmental policy in KOSTT which is under the procedure to

be adopted. Clear definition of environmental issues in KOSTT and orientation on what will be

done to control the environment, means planning. Planning is accomplished through new

projects, which are followed by the Environmental Impact Assessment. The implementation is

started by established the organizational structure, staff responsibilities, competencies and

training. Communication practices, control of documents and procedures, operational control

and emergency preparation, define the operational part of the program. These points are also

included in the EMS Manual (Environmental Management System) which will document a

program that has determined objectives and targets to be achieved. This Manual was developed

and has 18 procedures included which will be complemented with the Operational part, based

in practical requirements of the Transmission Operator and its operational plans. These, along

with routine monitoring conducted in the period 2013 – 202, reporting the situation recorded

along with appropriate recommendations, constitute a program of controlling acts and

corrective ones in EMS. Finally, a review of routine management activities is lowed by the

highest level in KOSTT the aim of which is to ensure future Environment protection and

sustainable development.

The long term environmental planning will support the benefit and KOSTT development plan,

by aiming:

- Proper financial management, which directs a better environmental control

Therefore all operational parts that have impact in environment will be included in KOSTT,

controlling the costs and its impact in the overall budget.

In addition to this, the following elements shall be respected:

- Domestic legislation (environment, energy)

- EU Legislation (environment, energy)

- Technical codes in KOSTT

- International standards and norms etc.


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More needs to be done to improve and update of the new technologies and in improvement of

the infrastructure of the operation system (SCADA) and transmission system (construction of

the double and triple lines. The world has advanced much in terms of environment, and we

have to progress in achieving the required and targeted goals.

REFERENCES

The following are references made on published studies and reports:

[1]Transmission Development Plan 2012-2021 /KOSTT

[2] Long term energy balance 2013-2020/KOSTT (proposed)

[3] Generation Adequacy Plan 2013-2020/KOSTT (proposed)

[4] List of new Transmission Capacities 2011-2020/KOSTT

[5] Grid Code – second edition /KOSTT

[6] Electrical Equipment Code/KOSTT

[7] Transmission Connection Charging Methodology /KOSTT

[8] Transmission System Security and Planning Standards/KOSTT

[9] Operating Security Standards/KOSTT

[10] Electrical Standard Code/KOSTT

[11]. Distribution Code/KOSTT-KEK

[12] ESTAP II: Feasibility Study for the Kosova – Albania 400 kV Transmission

Interconnection Project (CESI, September 2005), World Bank Grant #H048

[13] ENTSO-E (UCTE) Operation Handbook, Last Edition

[14]Energy strategy of Kosovo 2009-2018

[15] “Transmission Network Expansion Project” FICHNER

[16] International Standard ISO 14001: 2004

[17] Many domestic and EU environmental laws

(The end of document)


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Prepared Controled ISO 9001

Approved

Name and surname

Gazmend Kabashi Safete Orana Kadri Kadriu

subscription

Data 31. 10. 2012

transmission development plan 2013-2022

Documents

transmission network

transmission grid

planning requirements

kv network planning

planning methodology

longterm planning criteria

transmission system

relevant data