Basic Investigations

• Hydrological network• Water Basin Plans

Ranking of projects according to size, cost, environmental effects etc

Planning of Hydropower Projects

Purpose Oriented Investigations

Identify, investigate and select the best projects for a stated purpose. Benefit greatly from basic investigations

Investigation of Resources Planning Parameters and Data

• Power Demand• Hydrology• Topography• Geology, Soils and Materials• Environment• Socio-economic aspects• Tariffs and Tariff Policy or Market Price

Investigation of Resources Power Demand

• Demand• Supply systems• Energy conservation• Power market surveys• Demand forecast

Investigation of ResourcesPower Demand

Investigation of ResourcesHydrology

• Availability of hydrological data• Rainfall data• Supplementary gauging stations• Establishment of flow records• Reconstruction of flows• Projection of design flows• Overall average flow• Seasonal distribution of flows

Investigation of ResourcesHydrology (cont’d)

• Minimum flow• Run-off estimates• Water balance (rain, evaporation, flow)• Floods• Flood routing• Diversion during construction• Hydraulic design studies• Design flood (Probable Maximum Flood)

Investigation of ResourcesHydrology (cont’d)

• Operation studies• Software for power production• Direct diversion operation (run-of-river)• Reservoir operation• Power operations• Hydrological data required (duration curve)

Investigation of ResourcesHydrology

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1011121314151617181920

0 % 20 % 40 % 60 % 80 % 100 % 120 %

Percent of Time

Flow

, m3/

s

Investigation of ResourcesTopography

• Power = Efficiency x Head x Flow• Project layout• Catchment Area• Dam sites• Waterways• Power Stations• Transmission lines• Geology

Investigation of ResourcesGeology, soils and materials

• Exploration of foundation conditions• Reservoir water tightness• Reservoir slope stability• Seismic activity• Sediment problems in reservoirs• Sediment problems in structure design• Identify construction materials

Investigation of ResourcesEnvironment

• Diversion of water• Regulation and inundation• Impacts on settlements• Influence on climate• Impacts on fish and wildlife• Impacts on irrigation/agriculture• Increased malaria spread because of

reservoir (proposal from former class)

Investigation of ResourcesSocio-economic aspects

• Social benefits• Economic benefits

Investigation of ResourcesTariffs, tariff policy or market price

Country Households (UScent/kWh)

Commercial (UScent/kWh)

Average salary for employees (USD/year)

Comments

Tanzania 8 12 1 300 Tariff

Uganda 25-27 25-27 2 900 Tariff

Ethiopia 9 13 1 200 Tariff

India 6.25 12.5 4 500 Tariff state by state

Nepal 11 15 1 800 Tariff

Bhutan 3 5 3 500 Tariff

Belgium 15-20 15-20 30 000 Element of market price

Norway 8-20 8-20 50 000 Market price

PlanningThe hydropower development cyclePhase Large HPP Small/Mini HPP

Less than 10-20 MW

Preconstruction 3-5 years 1-2 years

ImplementationConstruction

3-8 years 1,5-3 years

Operation 50-100 years 30-50 years

PlanningThe hydropower development cycle Typical process resulting in

implementation of one HPP

• Reconnaissance studies of 20-30 schemes• Pre-feasibility studies of 3-5 schemes• Feasibility studies of 1-2 schemes

Go-ahead

PlanningThe hydropower development cyclePhase Large HPP Small/Mini HPP

Less than 10-20 MW

Preconstruction 3-5 years 1-2 years

ImplementationConstruction

3-8 years 1,5-3 years

Operation 50-100 years 30-50 years

PlanningThe hydropower development cycle

Project Planning Project Implementation Operation

3 - 5 years 3 - 8 years 50 - 100 years

DEFINITE PLAN ENGINEERING STUDY

CONSTRUCTION MANAGEMENT - SUPERVISION OF WORKS

MANUFACTURING, TRANSPORT AND ERECTION

DETAIL DESIGN WORKING DRAWINGS

COMMISSIONING OF WORKS

DESIGN AND PROCUREMENT

RECONNAISSANCE STUDIES

FEASIBILITY STUDIES

PRE_FEASIBILITY STUDY

OPERATION OF INSTALLATIONS

When is financial closure?

PlanningRequired expertise

• Project organisation• Power market• Economic and financial analyses• Hydrology/meteorology• Geodesy and surveying• Electro-mechanical engineering• Geology and rock mechanics• Soil mechanics• Erosion and sedimentology

PlanningRequired expertise (cont’d)

• Hydropower planning and design• Hydraulic structures• Operation and maintenance• Cost engineering• Quality engineering• Environmental baseline disciplines• Socio-economy

Reconnaissance StudiesMain Objectives

• Purpose oriented• Screening of rivers, kWh per km, etc• Identification of projects• Identification of alternatives • Desk studies on available data• Development of preliminary project

solutions, generation capacity, etc• Preliminary cost estimating

Reconnaissance StudiesMain Objectives (cont’d)

• Comparison of project alternatives• Ranking of projects for further

investigations• Listing of projects for further reference

Reconnaissance StudiesPersonnel

Reconnaissance studies require the most experienced personnel

• Hydropower Planner/Team Leader• Hydrologist• Engineering Geologist/Geotechnical exp• Various other experts• Support Personnel

Reconnaissance StudiesThe Environment

• Identification of obvious and severe environmental implications

• Search for mitigating solutions• Abandon if deemed necessarySevere impacts may be:• Inundation of large land areas• Interference with large habitations and

infrastructure• Severe changing of water regimes

Reconnaissance StudiesThe Study

• DATA COLLECTION• DESK STUDY

– Power demand– Flow– Head– Regulation possibilities and needs– Environmental constraints

Reconnaissance StudiesThe Study (cont’d)

• FIELD WORK AND DESIGN– Verification of desk study in the field– “Care of River” problems– Information of technical and environment

features– Information on habitation– Information on other socio-economic impacts– Confirmation of project concept

Reconnaissance StudiesThe Study (cont’d)

ESTIMATES AND SCHEDULES– Preliminary cost estimate– Contingencies– Preliminary implementation schedule

Reconnaissance StudiesThe Study (cont’d)

• ECONOMIC ASSESSMENT– Power generation assessment (kWh per year)– Unit cost of power (USc/kWh)– Ranking according to unit cost

• REPORT

Reconnaissance StudiesModel for Cost Estimate

1000 MU*)

1.0 General and preconstruction cost . . . . . . . . .10 Acquisition of land, water rights, right of way . . . . . . . . .20 Field investigat., hydrology, topography, geology . . . . . . . .2.0 Auxiliary works . . . . . . . . .10 Infrastructure and permanent installations . . . . . . . . .20 Temporary installations, camps, etc . . . . . . . .3.0 Civil works . . . . . . . . .10 Regulation works . . . . . . . . .20 Dams and intakes . . . . . . . . .30 Waterways . . . . . . . . .40 Power station . . . . . . . .

Reconnaissance StudiesModel for Cost Estimate (cont’d)

1000 MU*)

4.0 Electromechanical works . . . . . . . .10 Turbines . . . . . . . .20 Generators . . . . . . . .30 Control system . . . . . . . .40 Transformers and switchyard . . . . . . .5.0 Transmission lines . . . . . . .6.0 Engineering, management and administration . . . . . . .Cost Summary . . . . . . .Physical contingencies: 25% of 3.0, 10-15% of other items. . . . . . .GRAND TOTAL . . . . . . .*) MU = monetary units

Pre-feasibility StudiesSubject

• One or several defined projects

Objectives• Establishment of the need and justification of the project• Formulation of development plan for the project• Determination of the technical, economic and

environmental merits of the project• Definition of project limit• Recommendations for further actions

Pre-feasibility StudiesProject Formulation

METEOROLOGY

HYDROLOGY

SEDIMENT

MARKET SURVEYS

DEMAND FORECASTS

ALTERNATIVE SUPPLY

WATER STUDIES

POWER STUDIES

POWER & ENERGY BALANCE

HYDROPOWER INSTALLATION

OTHER SUPPLY

Pre-feasibility StudiesWater Studies

• Rain fall• Evaporation• Surface water• Groundwater• Quality of water• Water rights

Pre-feasibility StudiesWater Requirements

• Irrigation• Domestic and industrial water• Power generation• Navigation• Fisheries• Recreation• Wildlife and vegetation

Pre-feasibility StudiesVarious Studies

• Flood control• Sediment studies• Operation studies

Pre-feasibility StudiesEngineering

• Surveying and mapping• General geology• Foundation geology• Construction materials• Project plan• Cost estimates

Pre-feasibility StudiesOther Activities

• Power studies• Land resources survey• Land acquisition and resettlement• Environment (Initial Environment Examination)• Economic analysis• Financial analysis• Future investigations• Pre-feasibility study report

Pre-feasibility StudiesCheck-list

Collection and evaluation of existing data on:• Existing infrastructure• Power market (existing demand-future demand)• Topographical maps• Aerial photos and other photos• Hydrology records• Evaporation records• Geology records (geological maps, geological description, soil maps,

previous field investigation records (from prospecting, mining, road building etc)

• Sedimentation and erosion records• Seismicity records• Existing plans for hydropower development in the area• Environmental aspects• Present and future multipurpose considerations (irrigation, flood control etc)

Feasibility StudiesSubject

• One specific projectObjectives

• Determination of the technical, economic & financial, environmental and socio-economic feasibility of the project

• To constitute the basis for:– Financing– Authorisation and licensing– Compensation

• To constitute a firm basis for definite plan studies, detailed design and tender documents

Feasibility StudiesPower Market

• Supply of a new market• Extension of a existing market• Previous studies, review• History, stability/instability and market structure• Classification of load:

– Households– Industry– Public administration– Service– Transportation etc

• Historical trends• Future development scenarios• Energy conservation

Feasibility StudiesPower Market

• Important factors– Historical trends– Population growth– Economic development scenarios– Tariff policy– Substitution loads– Other supply alternatives– Load distribution, geographically– Load distribution, over time– Load factor(s)

Feasibility StudiesHydrology

• Must be firmly established• Quality tests• Gauging station programme• Checking rating curves• Establish run-off series >30 years if

possible• Establish critical flows, min / max

Feasibility StudiesTopography

• Catchment areas: Scale 1 : 50 000• General maps: Scale 1 : 10 000• Reservoir areas: Scale 1 : 25 000• Construction sites: Scale 1 : 2 000 or

1 : 1 000

Nowadays also digitalised maps are produced based on aerial photos

Feasibility StudiesGeology

• Continuation of pre-feasibility programme• Sub-surface exploration

– Core drilling– Seismic refraction– Pilot tunnels and shafts– Fraction, leakage and stress tests– Trenches and holes– Laboratory tests

• Field investigation report

Feasibility StudiesEnvironment

• Physical impacts caused by technical structures and installations– Mitigating the impacts by altering plans

• Impacts caused by the implementation of the project, direct and indirect– Subject of a separate study

• Part of the feasibility study• Require special assigned expertise

Thank you