desmond b seepersad writing sample

U.C.D. School of Mechanical and Materials Engineering

Mechanical Engineering Project

MEEN 30120

Modelling of Energy Flows during

Container Handling by Gantry Cranes

used at Sea-Ports

Author: Desmond Seepersad

Supervisor: Dr. David Timoney

April 2015

Modelling of Energy Flows during Container Handling by Gantry Cranes used at Sea-Ports

i

Copyright Declaration

This thesis is the copyright of the author’s original research. It has been composed by the author and

has not been previously submitted for examination which has led to the award of a degree.

The copyright of this thesis belongs to the author. Due acknowledgement must always be made of the

use of any of the material contained in, or derived from, this thesis.

Copyright © 2015 by Desmond Seepersad

All rights reserved


ii

Contents

Copyright Declaration .............................................................................................................. 1-i

Contents ..................................................................................................................................... ii

Abstract ..................................................................................................................................... iii

List of Figures ............................................................................................................................ iv

List of Tables ............................................................................................................................. iv

List of Graphs ............................................................................................................................. v

Glossary ..................................................................................................................................... vi

Acknowledgements ................................................................................................................. viii

Introduction ............................................................................................................. 1

1.1 Context and motivation .............................................................................................. 1

1.2 Irish ports .................................................................................................................... 5

1.3 Dublin Port ................................................................................................................ 10

1.4 Throughput at Dublin Port ........................................................................................ 15

1.5 Port Capacity ............................................................................................................. 17

1.6 Ports and their Environment ..................................................................................... 19

1.7 Ports as Energy Hubs ................................................................................................. 21

1.8 Air quality and Emissions .......................................................................................... 26

1.9 Dublin Ferryport Terminals (DFT) .............................................................................. 29

1.10 Rubber Tyred Gantry Cranes (RTGs) ......................................................................... 31

1.11 Overall Project Aim ................................................................................................... 38

1.12 Project Objectives ..................................................................................................... 38

1.13 Report Layout ............................................................................................................ 39


iii

Abstract

This project is centred on the issue of fuel efficiency of gantry cranes for container handling in use at

container terminals throughout the world. In particular, the possibility of regenerating a portion of

the energy used in the operation of the cranes through the use of energy recovery and storage

technologies is addressed. The method used was to undertake a literature review to gain an

understanding of the operation of the cranes and the potential energy recovery and storage

solutions. It was found that of all crane operations, hoisting and lowering of containers presents the

greatest energy recovery opportunity and that motion in the horizontal plane can be ignored.

Microsoft Excel and Visual Basic for Applications were used to develop a detailed calculation scheme

and user interface. It was calculated that the use of a flywheel ESS can result in a reduction in fuel

consumption of up to 50.09% while the use of a SC ESS offers the potential to reduce fuel

consumption by 28.34%.


iv

List of Figures

Figure 1.1.1: PM from ships navigating a port’s waterways .................................................................................. 2

Figure 1.1.2: Trans-European Transport Network .................................................................................................. 5

Figure 1.2.1: Irish ports and transport connections ................................................................................................ 7

Figure 1.2.2: LoLo tonnage profile 2012 [13] Figure 1.2.3: RoRo tonnage profile 2012 [13] ........................... 10

Figure 1.3.1: Aerial view of Dublin Port ................................................................................................................ 12

Figure 1.3.2: Overview of Dublin Port lands ......................................................................................................... 12

Figure 1.3.3: Current tenants leasing on the Dublin Port estate .......................................................................... 14

Figure 1.3.4: Energy consumption distribution as a percentage of total terminal energy consumption 2012 ..... 15

Figure 1.6.1: Sensitive natural environment of Dublin Port .................................................................................. 20

Figure 1.7.1: RTG share of total fuel consumption ............................................................................................... 25

Figure 1.10.1: Gantry cranes “Samson and Goliath” ............................................................................................ 31

Figure 1.10.2 Various Crane uses .......................................................................................................................... 32

Figure 1.10.3: RTG diagram .................................................................................................................................. 33

Figure 1.10.4: Hoisting mechanism known as a spreader .................................................................................... 34

Figure 1.10.5: Hoisting mechanism for spreader .................................................................................................. 35

Figure 1.10.6: Sample container handling operation ........................................................................................... 36

Figure 1.10.7: RTG diesel genset ........................................................................................................................... 36

Figure 1.10.8: Diagram of genset connection to hoist .......................................................................................... 37

List of Tables

Table 1.2.1: Three tiers of the Irish port system ..................................................................................................... 8

Table 1.2.2: Specialisation of Irish ports ............................................................................................................... 10

Table 1.4.1: Dublin Port Company overview ......................................................................................................... 16

Table 1.7.1: Terminal equipment at Dublin Port ................................................................................................... 22

Table 1.7.2: CO2 equivalent of diesel fuel consumption ........................................................................................ 23

Table 1.9.1: Dublin Ferryport Terminals specifications ......................................................................................... 30

Table 1.10.1 RTG diagram .................................................................................................................................... 33


v

List of Graphs

Graph 1.1.1: Throughput through Irish ports 1997 - 2011 ..................................................................................... 3

Graph 1.1.2: 30 year annual growth rate at Dublin Port 1990 - 2014 .................................................................... 4

Graph 1.2.1: Increase in port throughput 1998 - 2007 ........................................................................................... 6

Graph 1.2.2: Increase in tonnage of vessels calling at irish ports 2000 – 2011 [11] ............................................... 9

Graph 1.3.1: Composition of total tonnage at Dublin Port by category 2007 ...................................................... 13

Graph 1.4.1: Historical throughput at Dublin Port ............................................................................................... 16

Graph 1.4.2: Dublin Port’s share of Republic of Ireland’s tonnage 2002 & 2007 ................................................. 17

Graph 1.5.1: Dublin Port throughput projections for 2010 - 2040 ........................................................................ 19

Graph 1.7.1: Diesel fuel provides most of the energy input to container terminals ............................................. 22

Graph 1.7.2: Breakdown of fuel consumption showing the RTGs consume the most fuel ................................... 25

Graph 1.7.3: Breakdown of fuel consumption showing the RTGs consume the most fuel ................................... 25

Graph 1.8.1: World Health Organisation guidelines for PM10 exceeded in 2013 ................................................ 28

Graph 1.8.2: Sources and trends of So2 emissions 1990 - 2012 ........................................................................... 28


vi

Glossary

ACC Anthropogenic Climate Change

BCT Belfast Container Terminal

CAES Compressed Air Energy Storage

CAGR Compound Annual Growth Rate

CNG Compressed Natural Gas

CO Carbon Monoxide

CO2 Carbon Dioxide

COE Cost of Electricity

DCC Dublin City Council

DFT Dublin Ferry Port Terminal

DGPS Differential Global Positioning System

DMS Drive Management System

DPC Dublin Port Company

Draft Distance From Waterline To Keel Of The Vessel

Dwell Time Time Spent By Cargo At A Terminal Prior To Being Dispatched For Further Transport

EC Electrochemical Capacitors, Also Referred To As Ultracapacitor

EDLC Electric Double-Layer Capacitor

EMS Environmental Management System

EPA Environmental Protection Agency

EPF Ecoports Foundation

ERTG Electric Rubber Tyred Gantry

ERTG Electric RTG

ESPO European Seaports Organisation

ESS Energy Storage System

EU European Union

EV Electric Vehicle

FC Fuel Cell

GHG Greenhouse Gas

HGV Heavy Goods Vehicle

hp Horsepower

HSF High Speed Flywheel

Hz Hertz

ICG Irish Continental Group

kg Kilograms

kg/kWh Kilograms per Kwh

kJ Kilojoules

km Kilometres

km/h Kilometres per Hour

kW Kilowatts

kWh Kilowatt Hours


vii

l/h Litres per Hour

Li-Ion Lithium-Ion

LNG Liquefied Natural Gas

LoLo Lift On Lift Off

m/min Metres per Minute

m/s Metres per Second

MJ Megajoules

MS Microsoft

NaS Sodium–Sulphur

NCTV Noatum Container Terminal Valencia

NG Natural Gas

Ni-MH Nickel-Metal Hydride

Nox Oxides Of Nitrogen; Nitric Oxide (No) Or Nitrogen Dioxide (No2)

OPS On-Shore Power Supply, Also Referred To As Shore-Side Electricity

Pb-Acid Lead-Acid

PE Potential Energy

PERS Ports Environmental Review System

PM Particulate Matter

RES Renewable Energy Systems

RMG Rail-Mounted Gantry Crane

RoRo Roll On Roll Off (One Of Five Cargo Modes)

RPM Revolutions Per Minute

RTG Rubber Tyred Gantry Crane

SC Supercapacitor

SECA Sulphur Emission Control Area

SMES Superconducting Magnetic Energy Storage

STS Ship-To-Shore Crane

TEN-T Trans-European Transport Network

TESS Thermal Energy Storage Systems

TEU Twenty Foot Equivalent Units

TT Terminal Tractor

UHC Unburned Hydrocarbons

UI User Interface

Unladen units Containers That Are Shipped Through A Port Without Containing Any Goods

UPS Uninterruptible Power Source

US DOE United States Department Of Energy

V Volts

V2G Vehicle-To-Grid

VBA Visual Basic For Applications

VSD Variable Speed Drive

YICT Yantian International Container Terminal


viii

Acknowledgements

Firstly, I thank Dr. David Timoney for his invaluable assistance and guidance throughout the course

of this project. His honest feedback helped shape the progress of the project. I wold also like to

thank Mr. Ciaran Callan of Dublin Port Company and Mr. Alec Colvin of Dublin Ferryport Terminals

for their time and insight into the operation of a port terminal. Finally, I would like to thank John

Moran, senior technician at University College Dublin, for his support, encouragement and interest

during the execution of this project.


Chapter 1: Introduction - 1.1 Context and motivation 1

Introduction

1.1 Context and motivation

Anthropogenic climate change1 (ACC), environmental sustainability and energy efficiency are major

concerns of developed nations, governments, businesses and citizens. As unwanted and often

harmful emissions are the direct result of energy consumption in the form of fossil fuels, a reduction

in consumption levels leads to improved environmental compatibility. Hence, improving energy

efficiency typically has the knock-on effect of decreasing fossil fuel consumption and increasing

environmental sustainability. Significant work is undertaken on an ongoing basis by companies and

engineers to determine sources of energy wastage, opportunities for improved energy efficiency,

and means to exploit renewable energy systems (RES). While these efforts may initially seem costly,

they have great potential to reduce costs as a result of lower fuel consumption and to pose

opportunities for new business ventures [1]. For example, the member states of the European Union

(EU) have established an energy saving scheme to reduce the energy consumption level of 2005 by

20% until 2020 with the aim of generating cost savings of approximately €60bn per annum [2].

The concern over global climate change has increased in recent years leading to local, national and

regional governments becoming more heavily involved in the promotion and enforcement of

improved environmental sustainability. This is particularly relevant within the EU where, taking 1990

as a base year, the “Europe 2020” ten-year growth strategy aims by 2020 to reduce greenhouse gas2

(GHG) emissions by 20%, increase energy from RES to 20% and improve energy efficiency by 20%

[3]. The EU has further committed to reduce GHG emissions to 80%-95% of 1990 levels by 2050 [3].

In order to achieve these ambitious targets, it is wholly necessary to understand energy flows within

the major energy consuming industries [1].

1 Anthropogenic climate change is climate change as a result of human activities, namely the emissions of

greenhouse gases (GHGs) and in particular Carbon Dioxide (CO2).

2 Greenhouse gasses are the gaseous constituent of the atmosphere, both natural and anthropogenic, that

absorb and emit radiation at specific wavelengths. GHGs maintain earth at a habitable temperature, however

excessive concentrations lead to an increase in that temperature. GHGs include carbon dioxide (CO2), methane

(CH4), nitrous oxide (N2O), hydrofluorocarbons (HFCs), perfluorocarbons (PFCs) and sulfur hexafluoride (SF6).



Transportation is one of these sectors which contributes significantly to energy consumption across

the EU [4]. In fact, the transportation industry’s carbon footprint is deemed to be second only to the

energy industry [3]. “Clean Power for Transport: a European Alternative Fuels Strategy” was

launched by the European Commission in January 2013 with the aim of investigating opportunities

for reducing the energy intensity of the transportation network [4]. The entire transportation supply

chain is affected by this strategy. However, this is particularly relevant to the maritime transport and

port and logistic industries given their strategic importance as key drivers of international trade and

transporters of goods [4]. Hence, “Green Technologies and Eco-Efficient Alternatives for Cranes and

Operations at Port Container Terminals – GREENCRANES”, a project specific to port container

terminals (PCT), was launched and ran from August 2012 to May 2014 [4].

PCTs consume huge amounts of energy, particularly in the form of fossil fuels [5]. However, within

the global transportation supply chain they constitute a minor portion of the overall energy

consumption [3]. Furthermore, the majority of emissions at a given PCT can often be attributed to

ships navigating the PCT’s waterways or maintaining their engines in a standby position during

unloading [3].

Figure 1.1.1: PM from ships navigating a port’s waterways



But, it is difficult to attribute the emissions of a docked international vessel to a particular company,

PCT or even country. Nonetheless, nationally PCTs are considered to emit GHGs on an equivalent

scale to other heavy industries and hence are the focus of political efforts to reduce emissions and

improve energy efficiency [3]. Furthermore, the fossil fuels upon which the PCTs are so reliant are

mostly imported and subject to unstable price fluctuations [6].

Graph 1.1.1: Throughput through Irish ports 1997 - 2011

Although throughput at Irish ports experienced a sharp decline from 2007 to 2010 as a result of the

global financial crisis, those volumes have since returned to growth and are set to reach pre-crisis

levels in the immediate future [7].



Graph 1.1.2: 30 year annual growth rate at Dublin Port 1990 - 2014

This will subsequently lead to increased levels of related transportation services. Hence, in order to

meet the Europe 2020 targets, the transportation sector will have to make emission reductions

allowing for the overall increase in activity relative to 1990 [8].

Despite the reliance of the port and maritime transport industries on consumption of vast amounts

of energy, energy efficiency was not previously considered as an area of major importance [4]. The

Green Cranes project, funded by the Trans-European Transport Network (TEN-T ), aims to change

this mentality by highlighting the potential to implement energy efficiency improvements resulting

in cost reductions [4].


Chapter 1: Introduction - 1.2 Irish ports 5

Figure 1.1.2: Trans-European Transport Network

Port equipment and machinery are the main focus of the project as they constitute the majority of

the energy consumed by a PCT and hence provide vast opportunity to reduce fuel costs [4].

Additionally, the customers of PCTs are becoming increasingly interested in the perceived

environmental impact of their services [1]. It is thus acknowledged that port authorities must strive

to determine energy sinks and sources within their businesses to reduce costs and environmental

impact, improve their overall energy efficiency and relationship with their customers [1].

The Green Cranes project and other innovative efforts can provide solutions to the main

environmental issues faced by ports, but these approaches are occasionally met with resistance as

businesses are hesitant to invest in technologies which they fear could prove to be unsuccessful [9].

To avoid this uncertainty, it is first necessary to gain a better understanding of the energy flows

within the port and the surrounding areas [10]. This should involve both active monitoring and

calculation of the major energy flows within the port to determine the areas which represent the

greatest opportunity for efficiency improvements. Without such information, energy efficiency

measures cannot be effectively implemented [1]. Unfortunately, for the majority of ports worldwide

such monitoring programmes are absent [1]. Hence, it was the aim of this project to develop a

calculation scheme to estimate the energy usage in typical operating circumstances at a port.

1.2 Irish ports

As an island economy with 90% of GDP exported and seaports responsible for handling 99.5% of the

volume, equivalent to 62% of the value, of foreign trade, the Irish port network plays a crucial role in

facilitating economic growth across the island of Ireland [11-13]. Many of Ireland’s leading

employers and contributors to national GDP are exporters who rely on the port network to conduct

their business on international markets, examples include the pharmaceuticals, chemicals,

electronics, meat, dairy, and beverage industries [13]. In recent years, exports have been the only

net contributor to economic growth in Ireland and it is widely accepted that Ireland’s chances of

economic success rely heavily on the ability to trade internationally and hence rely on an adequate

and competitive port network [13, 14]. The Irish port governance model is coherent with the

approach taken in Europe, in that the port authorities are publically controlled with a large amount

of private sector involvement in the provision of ancillary services [11].



In the past 20 years, throughput at Irish ports has drastically expanded and contracted in line with

the wider economy. However, an EU wide comparison has shown that the port sector overreacts to

changes in the economy with large changes in throughput for moderate changes in economic activity

[15]. In the decade between 1997, when the Irish commercial ports were corporatized, and 2007,

when the effects of the global financial crisis were beginning to be felt, there was a 35% increase in

the quantity of goods moving through Irish ports with throughput reaching its peak at 54.1 million

tonnes (t) in 2007 [11].

Graph 1.2.1: Increase in port throughput 1998 - 2007

Unitised traffic was responsible for a large portion of the increase as it almost doubled in the period.

Subsequently, overall volumes plummeted by 30% in 2008 and 2009 with marginal improvements

being made in the following years [11]. Currently, throughput is at the level seen approximately a

decade ago [11]. Such major decline has alleviated concern over national port capacity but is likely to

become an issue once again as the economy recovers and begins to grow in the coming decade [16].



Irish ports are spread around the island’s coastline and vary significantly in size and hence overall

contribution to the national economy.

Figure 1.2.1: Irish ports and transport connections

The National Ports Policy categorises the Irish ports into three tiers; Tier 1 - Ports of National

Significance (with between 15%-20% of national tonnage), Tier 2 - Ports of National Significance

(with at least 2.5% of national tonnage), Tier 3 - Ports of Regional Significance (remaining

commercial ports) [11].



Tier 1 Tier 2 Tier 3

Dublin Port Company Port of Waterford Company Bantry Bay Harbour Authority

Port of Cork Company Rosslare Europort Castletownbere Fisheries Centre

Shannon Foynes Port Company Drogheda Port Company

Dundalk Port Company

Dún Laoghaire Port Company

Galway Port Company

Greenore Private Ownership

Killybegs Fisheries Centre

Kinsale Local Authority

New Ross Port Company

Sligo Local Authority

Tralee Fenit Local Authority

Wicklow Port Company

Youghal Table 1.2.1: Three tiers of the Irish port system

Tier 1 ports are seen as the primary gateways to the Irish economy and must operate on an efficient

and cost-effective basis if Ireland is to undergo economic recovery and development [11]. Thus, if

ports operate inefficiently or charge excessively high rates, economic growth in the country will be

dampened [13].

In order to expedite Ireland’s economic recovery, transportation costs must be reduced and kept to

a minimum. It has been suggested that an increase in transport costs of 10% can lead to a reduction

in trade volumes by as much as 20% [13]. An efficient, high-quality, port marketplace can achieve

these cost reductions, through inter-3 and intra-4 port competition [13]. With different ports

competing for the same cargo, efficiency is maximised and charges for importers and exporters are

minimised resulting in a more attractive marketplace for businesses [13]. Alternatively, competing

terminals and service providers within a single port act to reduce the overall costs of doing business

at that port [11]. However, inter-port competition can often be low due to restrictions on the flow of

goods through certain ports because of geographical location and hence access to international

shipping lanes, road transport and ancillary services [11]. As a direct result, certain ports enjoy a

competitive advantage due to their location. For example, the ports at Dublin, Cork and Belfast

3 Inter-port competition is the competition between different ports for the same cargo

4 Intra-port competition is the competition within a port for different cargo types



benefit from their proximity to major urban concentrations and hence can offer a higher level of

choice and service frequency of ancillary service provision, something that appeals to load-on-load-

off5 (LoLo) terminal users [11, 13]. The large size of these ports also appeals to container shipping

lines as they can facilitate larger, more efficient vessels and cranes – an approach preferred by many

global shipping lines6 as is clear from the data presented in Appendix A [11, 13].

Graph 1.2.2: Increase in tonnage of vessels calling at irish ports 2000 – 2011 [11]

The economic recession has increased this trend with cargo traffic moving towards larger ports in

search of reduced costs as shown in the below figure [11]. This trend leads to further issues relating

to the depths of water required at ports and the type and scale of transport connections to the

hinterland [11]. Dublin Port and Belfast Harbour can also provide the shortest sea crossing the

United Kingdom which enables them to offer shorter travel times and hence appeal more to the

Roll-On-Roll-Off (RoRo) market segment [13]. This had led to the RoRo market becoming

concentrated on the east coast as shown below. Low levels of competition due to geographical

advantage is avoided through intra-port competition established through implementation of a

landlord-type operating model [11]. Port specialisation, where a port or terminal aims to provide a

low variety of services to improve those fewer services, can also reduce the level of competition

within the marketplace as there will be fewer providers competing for the same freight types. This

5 LoLo is containerised or otherwise unitised cargo. LoLo cargo must be loaded to and from ships by means of

either portside or on-board ship-to-shore cranes

6 In 2000 the average gross tonnage of commercial vessels entering Irish ports was 1,095 tonnes; by 2011 an

increase of 69% occurred, increasing the number to 1,855 tonnes.


Chapter 1: Introduction - 1.3 Dublin Port 10

has resulted in Dublin Port handling 57% of LoLo and 43% of RoRo freight, Shannon handling 42% of

dry bulk freight and Cork handling 33% of liquid bulk freight [11].

2012 % Total

% Ro/Ro

% Lo/Lo

% Liquid

% Dry

Dublin 29% 43% 57% 22% 9%

Shannon 15% 0% 0% 7% 42%

Cork 13% 0% 18% 33% 9%

Table 1.2.2: Specialisation of Irish ports

In general, Dublin and Belfast compete for RoRo freight, Waterford and Cork compete for LoLo

freight while Shannon Foynes and Cork compete for dry bulk [13].

Figure 1.2.2: LoLo tonnage profile 2012 [13] Figure 1.2.3: RoRo tonnage profile 2012 [13]

1.3 Dublin Port

Dublin Port, shown overleaf, is Ireland’s largest seaport and is located at the hub of national road

and rail networks, adjacent to the Poolbeg power generation facility and within 4 kilometres (km) of

the centre of Dublin city [17]. Dublin Port is Ireland’s second largest industrial estate, operating 24



hours a day with 4,000 people employed in the port area and sprawling over 260 hectares (650

acres) with approximately 14km of waterfront in the capital, also shown overleaf [12, 18, 19]. Dublin

Port handles an estimated 42% of Ireland’s gross domestic product (GDP) [12]. The land is mainly

used for LoLo/Roll-On-Roll-Off terminals and berths, quayside loading and unloading operations

including the necessary equipment and container storage locations, bulk materials handling and

other commercial and industrial activities [18]. Dublin Port is considered Ireland’s key gateway for

both imports and exports as it provides vital port capacity for the Irish economy at a scale location

favoured by many of the international shipping lines and ferry operators [16, 17]. Dublin Port

handles approximately 50% of Ireland’s trade, including 70% of LoLo and 85% of RoRo trade making

up two thirds of all containerised freight in Ireland [11, 17]. Dublin Port also provides very significant

amounts of liquid bulk fuels for consumer markets [14]. In recent times, over 1.76 million visitors

have travelled through Dublin Port each year availing of the ferry and cruise services operated from

the port [17]. Dublin Port is the largest of only three base ports7 across Ireland and Northern Ireland

(NI), with the ports at Belfast and Cork making up the remainder [17].

7 Base ports offer multimodal services with connections to transhipment ports such as Rotterdam and are

important strategic trading hubs.



Figure 1.3.1: Aerial view of Dublin Port

Figure 1.3.2: Overview of Dublin Port lands

These base ports are the only ports on the island of Ireland able to handle all the major cargo types;

RoRo, LoLo, Dry Bulk, Liquid Bulk, Break Bulk [12].



Graph 1.3.1: Composition of total tonnage at Dublin Port by category 2007

Despite most of Ireland’s ports being constructed at rail heads, only the ports at Dublin and

Waterford receive rail freight [11]. This may prove to be of great significance in future as multi-

modal distribution can provide the most effective means of transportation of goods throughout the

hinterland without conflicting with changes to environmental and charging regulations [11]. The

above makes Dublin Port a very substantial component of Ireland’s productive infrastructure and is

vital to the recovery of the economy and any potential future development [14]. Thus, of all the Irish

ports to focus on when investigating the potential for operational improvements through energy

recovery and storage, Dublin Port is a clear choice.

Dublin Port Company (DPC) is Ireland’s largest port company, it was established in 1997 when the

Irish commercial ports were corporatized, it is a private limited company owned entirely by the Irish

state, and it is self-funded and owns the Dublin Port estate. The primary purpose of DPC is to

facilitate the movement of passengers and cargo through the port by providing and maintaining the

port’s infrastructure [20]. DPC operates a landlord-type operating model whereby it manages the

property and development of the port and is responsible for the licensing and leasing of the land,

infrastructure and facilities to private companies and port operators [11, 14, 16, 17].



Figure 1.3.3: Current tenants leasing on the Dublin Port estate

While Dublin Port competes with the other major port companies across the island, there is

significant competition within the port itself for unitised trade between the eight private terminal

operators, and between ancillary service providers [17]. DPC published its Masterplan in February

2012 outlining its plans for development through to 2040. The primary objectives are to; maximise

usage of existing port land area, reintegrate the port with the city, develop the port to the highest

environmental standards [11]. However, this does not mean operating at 100% capacity, as spare

capacity is necessary in order to provide competition for trade taking place at other ports [14].

Instead increased utilisation can be achieved by improving the load-bearing properties of the ground

and investing in better handling equipment [16]. DPC also clearly acknowledges that in order to

continue to provide a market leading service, it will need to maintain and improve its operational

efficiency and environmental standing. The issues of improved handling equipment, operational

efficiency and environmental performance can be addressed, at least in part, through the use of the

results obtained through this project.

With approximately 50% of Ireland’s trade passing through Dublin Port, and 80% of Dublin Port’s

trade comprised of unitised/containerised cargo, this cargo mode emerges as the one of key

importance [12, 17]. Furthermore, as Ireland’s economy is export led and exports are primarily

containerised, the value of optimising the handling of containerised cargo cannot be understated

[13]. Since containerisation was introduced globally in the 1960s, it has had a massive impact on the

operation of Irish ports as ports could standardise their services and move towards larger more

efficient port models as can be seen at Dublin Port. This led to reduced transport costs and increased

reliability of the cargo network, resulting in a more level playing field for economies which were

previously being out-priced due to the high cost of transportation [13]. Consequently, the Irish

economy benefitted enormously and has become a global hub for high value manufacturing reliant

on an excellent distribution and transport network for exports [19]. If such economic growth is to be

achieved once again, no doubt exports will play a significant role and hence further improvement to

the containerised market must be achieved. The Green Cranes project identified that container

handling is responsible for up to 90% of a port’s energy consumption and that this consumption

relates specifically to LoLo trade as RoRo handling requires much less input from the terminal

operator [4]. Additionally, a monitoring programme in South America measured that fossil fuel


Chapter 1: Introduction - 1.4 Throughput at Dublin Port 15

delivered the majority of each terminals energy requirements and that energy input was again due

to container handling [1].

Figure 1.3.4: Energy consumption distribution as a percentage of total terminal energy consumption 2012

Thus, to achieve the necessary improvements in the handling of containers at Irish ports, specifically

Dublin Port, an understanding and subsequent optimisation of the energy consumption in this area

is needed. This defines the overall aim of this project; to develop a calculation scheme to estimate

the energy usage in container handling cranes at Dublin Port with the goal of specifying reductions in

this consumption through the use of energy recovery and storage technology.

1.4 Throughput at Dublin Port

In the two decades preceding 2008 the Irish economy enjoyed above average growth in exports and

consequently the national port network underwent vast increases in throughput, as shown in the

below graph [16]. By 2007, total throughput at Dublin Port had quadrupled from its 1980 position,

with RoRo tonnage increasing nine fold from a share of 24% to 55% and LoLo increasing to almost six

times its 1980 value from 16% to 23% of throughput at the port. At the same time non-unitised

cargo decreased from 61% to 22% of total throughput, this highlights the very pronounced rise in

unitised trade and hence the increased importance of this cargo mode into the future as the


Chapter 1: Introduction - 1.4 Throughput at Dublin Port 16

economy recovers and moves towards growth once again [16]. These overall increases in the

quantity of cargo moved through the port are reflected in the company’s historical performance as

shown in the table below.

Dublin Port Company overview Year

1998 2010 2011

Tonnage (’000) 13,240 19,548 19,467

Turnover (€’000) 45,240 66,969 69,111

Operating Profit (€’000) 20,415 27,031 27,830

Profit after Interest and Tax (€’000) 14,063 20,534 27,911

Employees 455 152 145

Table 1.4.1: Dublin Port Company overview

Graph 1.4.1: Historical throughput at Dublin Port

1,888 2,186 2,3904,895

11,36014,888

17,154 17,093

1,237 1,247 2,062

3,101

4,452

5,815

7,152 5,679

4,807 2,9953,184

3,885

5,187

6,219

6,6575,341

0

5,000

10,000

15,000

20,000

25,000

30,000

35,000

1980 1985 1990 1995 2000 2005 2007 2010

Throughput(thousand tonnes)

Year

Historical throughput at Dublin Port

RoRo LoLo Other Cargo


Chapter 1: Introduction - 1.5 Port Capacity 17

Throughout this period, Dublin Port has held the largest share of unitised trade of any port in Ireland

and has grown its share of overall Irish tonnage through the port networks as shown below [14].

Graph 1.4.2: Dublin Port’s share of Republic of Ireland’s tonnage 2002 & 2007

1.5 Port Capacity

Across the entire island, there are seven LoLo ports, but particular importance should be placed on

the ports at Dublin and Belfast due to the size of their respective shares of total LoLo throughput

[14]. In 2008 the theoretical capacity 8of the LoLo ports across the island amounted to 1.97 million

twenty-foot equivalent units9 (TEUs), with 1.56 million TEU of capacity located in Ireland – and

8 The LoLo Terminals theoretical capacity of 900,000 TEU’s providing that the terminals are actively managed

with an average container dwell time of no more than 5 days

9 Twenty foot equivalent unit (TEU), the standard measure in the container industry used to specify the

capacity and throughput of ports, terminals, shipping vessels and countries

76.5%

57.3%

26.1%

8.8% 9.1%

34.6%

75.3%

64.0%

28.4%

16.3% 13.9%

40.3%

0.0%

10.0%

20.0%

30.0%

40.0%

50.0%

60.0%

70.0%

80.0%

90.0%

100.0%

RoRo LoLo Liquid Bulk Dry Bulk Break Bulk andOther

Total

Percentage

Cargo Mode

Dublin Port's Share of RoI Tonnage2002 & 2007

2002 2007


Chapter 1: Introduction - 1.5 Port Capacity 18

900,000 TEU of capacity located at Dublin Port alone [14]. This further emphasises the need to focus

on Dublin Port regarding energy consumption and recovery.

The global financial crisis has had very severe negative effects on the national economy and

consequently on the ports [14]. This resulted in a sharp contraction in national throughput at the

ports from the peak of 2007 and has led to both an excess in port capacity and unstable demand for

the port services. The impact of the decline in throughput varied across the ports and cargo modes.

On a national level between 2007 and 2008, LoLo decreased by approximately 10% and RoRo along

with all Bulk trade decreased by 5% [14]. Furthermore, between 2009 and 2011 LoLo decreased an

additional 8% while RoRo actually increased by 8% [11]. These contractions alleviated some of the

concern regarding port capacity in the short-term, but at time of writing (2015) throughput is

approaching the quantities of a decade ago and is beginning to show signs of growth, hence

additional port demand is forecast for the post 2030 period or as early as the decade beginning 2020

for the LoLo market [11, 14, 19]. The Dublin Port Masterplan predicts that by 2040 a doubling of the

peak LoLo throughput experienced in 2007 will have occurred, resulting in over one million TEUs

passing through Dublin Port and far exceeding the 2007 peak of 743,947 TEUs and the theoretical

current capacity including any potential increase due to improved efficiency [16]. This assumes a

compound annual growth rate (CAGR) of just 2.5% which is below that experienced in the two

previous 30 year periods as shown in the table below [21]. If the growth rates experienced in the

three years prior to this project are sustained, it is very likely that the CAGR will be above 2.5% and if

growth returns to the scale experienced in the five years preceding 2007 CAGR will far exceed this

level [14, 21]. This will result in the need to develop additional port capacity somewhere in Ireland,

and very probably at Dublin Port as there is existing land suitable to bring LoLo capacity to

approximately 1.9 million TEUs [14, 19]. The projections from throughput at Dublin Port are shown

below. Performance improvements should be established in advance of implementing any new

capacity. Hence, gaining an understanding of the energy flows during LoLo container handling and

initiating appropriate energy saving technologies will be of great importance to ensure that

additional capacity is as effective as possible.


Chapter 1: Introduction - 1.6 Ports and their Environment 19

Graph 1.5.1: Dublin Port throughput projections for 2010 - 2040

1.6 Ports and their Environment

Ports operate at a complex interface of very different environments, the land and the foreshore.

Furthermore, many ports, such as those in Ireland, are located at river estuaries which are

surrounded by diverse and often protected natural habitats. This interface leads to unique and

elaborate considerations when managing or developing port land and infrastructure [11]. The Dublin

Port estate is situated within the Eastern River Basin District and surrounded by a dynamic natural

environment, adjacent to two areas of international importance designated as a Special Protection

Area and a Special Area of Conservation as illustrated below [19].


Chapter 1: Introduction - 1.6 Ports and their Environment 20

Figure 1.6.1: Sensitive natural environment of Dublin Port

In 2014, in their environmental policy, DPC recognises the sensitivity of these locations and states

that they will continue with a positive focus on nature conservation at these sites and other

surrounding areas [20]. DPC goes on to specify that they will use best environmental practice to

ensure that pollution prevention is sought throughout all operational activities [20]. This will require

great sustained effort as there are many industrial facilities in the immediate vicinity and the Dublin

City Development Plan 2011-2017 highlights that Dublin Port is zoned as Z7, stipulating that it should

aim “to provide for the protection and creation of industrial uses and facilitate opportunities for

employment creation” [18]. This then may seem to be at odds with the DPC environmental policy,

however both objectives can be achieved if a sustainable and energy efficient approach is taken,

such as is outlined by the results from this project.

In 2008 and again in 2010, DPC attained the Ports Environmental Review System (PERS) certification

from the Ecoports Foundation (EPF). The EPF was comprised of ports and related stakeholders who

shared environmental experiences, in January 2011 EPF was combined into the European Seaports


Chapter 1: Introduction - 1.7 Ports as Energy Hubs 21

Organisation (ESPO) [22]. This certification is subject to external assessment every two years by

Lloyd’s Register [23]. DPC is also compliant with ISO 14001 for the use of a suitable Environmental

Management System (EMS). The commitment to PERS and ISO 14001 pushes DPC to make

operations throughout the estate as sustainable as possible. Compliance with these internationally

recognised standards benefits the surrounding environment and the business conducted within the

port estate. Compliance can be sustained through actively seeking and implementing efficiency

improvements throughout the port operations and especially when considering expansion of

existing facilities. This further highlights the need and potential for a project to focus on reduced

energy consumption.

1.7 Ports as Energy Hubs

Ports can often be considered as energy hubs10 due to their location adjacent to high energy supply

and demand activities such as power generation, densely populated urban areas and the energy

intense activities that take place within the port estate itself [10]. This adds to the importance of

understanding the energy consumption and emissions within ports as there is both the potential for

harm to nearby urban populations due to emissions and vast possibilities regarding alternative fuels

as a result of proximity to power generation facilities combined with being a centre for international

transportation [10]. This is particularly true for Dublin Port which can accurately be described as an

energy and transportation hub. Of the eight private terminals operating at Dublin Port, Terminals 1,

2, 3 and 5, located on the north side of Dublin Port facilitate the RoRo operations. Tabulation of the

important specifications of these terminals and services they offer can be found in Appendix B [16].

Additionally there are three container terminals, each facilitating a number of container shipping

companies [16]. These terminals employ specialised heavy duty equipment for the loading and

unloading of container shipping vessels. They also maintain secure storage facilities for containers

awaiting transport to the hinterland or loading onto vessels [16]. A table detailing the important

specifications and the equipment used at each of the terminals can be found on the following page.

As can be seen in the table, cranes are the main equipment used, with rubber tyred gantry cranes

(RTGs) and rail mounted gantry cranes (RMGs) as well as mobile harbour cranes and ship to shore

10 An energy hub is a location where high levels of energy generation and consumption are situated. These

energy intense activities can include; industrial installations, power generation and other similar businesses



cranes (STS) providing the majority of the lifting and manoeuvring capabilities [16]. Images of each of

these cranes is provided in Appendix C.

Table 1.7.1: Terminal equipment at Dublin Port

The operations within the Dublin Port estate consume vast amounts of energy primarily in the form

of fossil fuels, namely diesel [19]. A study carried out from 2011 to 2012 across thirteen terminals in

four countries in South America (Argentina, Uruguay, Chile, and Paraguay) found that the majority of

energy input to terminal operation, approximately 70%, comes in the form of diesel fuel [1].

Graph 1.7.1: Diesel fuel provides most of the energy input to container terminals

Parameters Dublin Ferryport Terminals (DFT)

Marine Terminals Limited (MTL)

Common User Terminal (CUT)

Berth Length/s 360m + 180m 700m 900m

Berth Depth/s 9.5m + 11.0m 10.2m 10.0m

Cranes (Ship/Shore)

3 3 5

Crane Type Ship Gantry Ship Gantry Harbour Mobile

Gantries (Container)

8 4 6

Gantry Type RTG RMG RTG

Reefer Points 275 270 252

Area (Hectares)

14.0 Hectares 15.1 Hectares 12.3 Hectares

Parent company

Irish Continental Group Peel Ports Group

Portroe Stevedores (PSL)



The significant energy inputs demanded by these cranes and the consumption of such vast amounts

of diesel fuel directly leads to the emission of known pollutants and GHGs such as Carbon Dioxide

(CO2) and Carbon Monoxide (CO). CO is formed through the incomplete oxidation of fuel during

combustion and hence can form in areas of high levels of traffic congestion or where there are diesel

driven generators such as those used at ports to power the container handling equipment [24]. The

results from the Green Cranes study at the Noatum Container Terminal Valencia (NCTV) show that in

a single year at just one terminal, the CO2 emissions can vary from 372 tonnes to 6,868 tonnes

across families of RTG as shown in the below table.

RTG FAMILIES DIESEL CONSUMPTION (l) CO2 (Tonnes)

2011 2012* 2011 2012*

RTG A.1 64,837 84,364 168 219

RTG A.2 78,710 91,152 204 236

SUBTOTAL FOR FAMILY A

143,547 175,516 372 455

RTG B.1 1,113,110 1,107,421 2,884 2,869

RTG B.2 1,537,785 1,519,685 3,984 3,938

SUBTOTAL FOR FAMILY B

2,650,895 2,627,106 6,868 6,807

RTG C.1 178,613 178,512 463 463

RTG C.2 884,924 834,520 2,293 2,162

SUBTOTAL FOR FAMILY C

1,063,537 1,013,032 2,756 2,625

TOTAL 3,857,979 3,815,654 9,996 9,887

Table 1.7.2: CO2 equivalent of diesel fuel consumption

The Green Cranes project further highlighted that at two of the three container terminals under

study, RTGs were the single largest user of diesel fuel of all the yard machinery as shown in the

below figures [5].



RTGs63%

Yard Tractors33% Reach

Stackers3%

Empty Forklifts

1%

Yard Machinery Total Fuel Consumption NCTV 2011



Graph 1.7.2: Breakdown of fuel consumption showing the RTGs consume the most fuel

Graph 1.7.3: Breakdown of fuel consumption showing the RTGs consume the most fuel

In terms of aggregated data, the study found that 90% of the total fuel consumption was a result

from RTGs and terminal tractors (TTs).

Figure 1.7.1: RTG share of total fuel consumption

Misc.2%

Forklifts6%

Yard Tractors7%

Reach Stackers

20%

Road Tractors31%

RTGs34%

Tractors38%

Yard Machinery Total Fuel Consumption Port of Koper 2011


Chapter 1: Introduction - 1.8 Air quality and Emissions 26

Due to the nature of the operation of RTGs and TTs, it is clear that RTGs offer the greatest

opportunity for improved efficiency through energy recovery due to their larger share of

consumption and their primary function of raising and lowering loads. This process lends itself to

energy recovery as the load is lowered. Dublin Port is committed to their environmental obligations

and will play a significant role in enabling Ireland to meet its Europe 2020 targets of reducing GHG

emissions and improving energy efficiency. Hence this project focussed on the development of a

calculation scheme relating to the hoisting operations at Dublin Port using RTGs with the aim of

specifying the potential for energy saving activities if energy recovery or storage technology was

implemented. This reductions could lead to cost savings and increased competiveness due to

improved environmental credentials [1]. A more efficient and sustainable Dublin Port is also likely to

garner more support for expansion if capacity requirements demand such action.

1.8 Air quality and Emissions

Concentrations of high levels of fossil fuel combustion can lead to serious concerns over air quality.

As energy hubs - often located within short distances of large urban populations - ports with their

associated industrial activity and vehicular movement certainly meet the criteria to raise concern

over air quality. As previously highlighted, this is particularly true for Dublin Port given its reliance on

sea-going vessels, heavy machinery, transport infrastructure and its proximity to power generation

facilities and the largest conurbation in Ireland. Hence, monitoring emission levels and maintaining

them below safety guidelines is of crucial importance to Dublin Port and the local communities. The

most important pollutants in the Dublin Port area are oxides of nitrogen11 (NOx), particulate matter

(PM) especially PM1012 and sulphur dioxide (SO2) as these are the pollutants known for having

negative effects on human health, and in the case of SO2 for causing acid rain [18]. Combustion at

high temperatures in transport and power generation are the primary producers of NOx, PM

emissions also result from vehicular traffic but can be formed from burning solid fuel too, SO2 gas is

formed by combustion of fuels containing sulphur such as coal and oil such as that used in many sea-

faring vessels [25]. Locally, dust emissions from operations within the port estate or construction

11 The majority of NOx emissions are comprised of NO, with typically 5 ‐ 10% being directly emitted NO2. Diesel

engines tend to emit a higher percentage of NO2

12 Particulate matter with diameter of 10m or less



relating to the port can also cause concern. Air emissions can be temporarily increased by additional

throughput of LoLo and RoRo due to emissions from container handling and vehicular movement

[19]. Occasionally, this can result from the pronounced weekly cycles of LoLo throughput at Dublin

Port as peak arrivals occur on Sunday and early Monday. Hence, there is above average activity in

terms of docked vessels and container handling equipment during this time [16]. Thus, it is clear that

these harmful emissions will be generated in the Dublin Port area and efforts must be taken to

monitor and maintain them below safe levels, the levels considered as safe are given in Appendix D.

With regard to SO2, the EU Sulphur Directive came into effect on January 1st 2015, and encompasses

all ships transiting the area designated as a sulphur emission control area13 (SECA). This directive

requires all ships travelling through these waters to use fuel with a sulphur content of 0.1%,

significantly lower than the previously allowed 1% sulphur content. This is primarily aimed towards

improving air quality as sulphur dioxide emissions can lead to acid rain and generate fine dust which

is dangerous for human health, causing respiratory and cardiovascular diseases and reducing life

expectancy in the EU by up to two years [26]. However, this fuel is more expensive and those costs

will likely by passed down the supply chain resulting in an increase in the cost of container transport

[27]. This highlights both the need for businesses in the container transport industry to meet their

environmental obligations and also aim to reduce costs where possible. Hence, a project such as this

which aims to achieve both these goals can be very beneficial.

In 2009 and again in 2011, DPC monitored air quality within the estate with the intention of

obtaining accurate measurements of NOx, SO2 and PM. The results showed that the air quality inside

the estate is broadly similar to that in Dublin city, for example NO2 levels were largely below

legislative limits only exceeding the limit occasionally, SO2 levels were measured to always be below

the legislative limits and PM levels were within legislative limits [22]. Despite being within the

legislative limits of 40 μg/m3, concentrations of PM10 for the Dublin region exceeded the World

Health Organisation (WHO) air quality guidelines as shown below [24].

13 SECA includes the Baltic Sea, the North Sea and the English Channel



Graph 1.8.1: World Health Organisation guidelines for PM10 exceeded in 2013

Due to fuel switching from solid and liquid fuels to natural gas, particularly in the power generation

and industrial sectors, Ireland met the national emission ceiling14 in 2009 as a result of the large

decreases in SO2 emissions as shown overleaf.

Graph 1.8.2: Sources and trends of So2 emissions 1990 - 2012

14 The emission ceiling is implemented by the European Commission, Ireland’s ceiling is 42,000 tonnes


Chapter 1: Introduction - 1.9 Dublin Ferryport Terminals (DFT) 29

The coal-fired power generation facility at Moneypoint was a key emitter of SO2 that managed to

enact substantial reductions through implementing flue gas desulphurisation [24]. However,

excessive NOx levels caused Ireland to fail to reach the emissions ceiling in 2010, with the

Environmental Protection Agency (EPA) measuring excessive NO2 levels in a particular location in

Dublin city [18]. Dublin City Council (DCC) identified that the air quality monitoring stations

applicable to Dublin Port are those located at Marino and Ballyfermot due to their immediate

proximity as well as those situated at Winetavern Street, Coleraine Street and Ringsend as they are

within 4km of the port estate [22]. The results from these locations obtained between 2007 and

2009 showed once again that NO2 levels exceeded the legislated limit on certain occasions [22]. This

highlights the serious need to monitor emission levels and maintain them below legislative limits and

those deemed safe for nearby populations. Reducing fuel consumption in the container handling

equipment is an approach that among others will assist in achieving this goal.

Noise pollution is also an issue for Dublin Port as despite being primarily surrounded by industrial

facilities, it also shares the locality with residential areas and the city of Dublin. The emission of noise

from Dublin Port mostly arises from the RoRo and LoLo terminals, container storage areas and traffic

moving through the port estate [18]. If the trend outlined above regarding the increasing size of

container vessels continues then it is possible that there will be the need to extend RoRo and LoLo

operational hours at night [19]. This will be of concern as night-time noise poses a more significant

disturbance to the local community. In recent years, DPC have implemented noise monitoring within

the port estate to monitor their noise emissions. From the perspective of the DPC, little can be done

to minimise the noise due to traffic, but there is the potential for improvement in the LoLo terminals

through implementing the recommendations of this project which would bring about lower noise

levels generated.

1.9 Dublin Ferryport Terminals (DFT)

This project focussed on the container handling terminal of Dublin Ferryport Terminals within the

Dublin Port estate. Such a selection is appropriate as DFT operate the largest number of RTGs (8) of

the three container handling terminals in the port. Furthermore, DFT’s parent company Irish

Continental Group (ICG) also operates Belfast Container Terminal (BCT) at Belfast Harbour, thus any


Chapter 1: Introduction - 1.9 Dublin Ferryport Terminals (DFT) 30

operational efficiency improvements that can be calculated can be shared with BCT where possible

[28]. ICG was formed in 1972 as Irish Continental Line through an Irish-Scandinavian venture with

the aim of providing a direct ferry connection between Ireland and mainland Europe. In 1992, ICG

expanded into container transport and port operations through the purchase of B&I line from the

Irish government. Since 2000, ICG has invested over €500 million in port infrastructure, new vessels

and acquisitions [29]. This has enables ICG to provide both port services and RoRo and LoLo

transport [30]. ICG state that their leased 33 acre terminal at DFT with 480 metres of berths up to 11

metres in depth, located within one kilometre of the Dublin Port Tunnel providing immediate access

to the national motorway network, is the most modern in the Dublin Port estate [31]. In

combination with connections to other Irish ports (Cork and Belfast) DFT operates high frequency

container freight services to the important European ports of Rotterdam, Antwerp and Le Havre

(Radicatel) [32]. The specifications of the terminal are given in the table below [32].

DFT Terminal Specification

Capacity 450,000 TEUs

Length of Berths 1 x 360 meters @ 9.5 meters depth

1 x 180 meters @ 11 meters depth

Ship to shore cranes 3 x 40 tonne STS (Liebherr, 2 with full curve going facility)

Secondary handling equipment 8 x 40 tonne RTGs (3 x Liebherr/5 x Kalmar)

1 x 45 tonne Reachstacker (Kalmar DRF)

4 x empty container handlers

2 x 18 tonne Fork lift (Hyster)

Reefers 275 points

Table 1.9.1: Dublin Ferryport Terminals specifications

In addition to DFT and BCT, ICG operate the intermodal shipping line Eucon and a ferry division,

making ICG the leading Irish marine transport operator [30]. Eucon operates a fleet of chartered

container vessels with sizes ranging in capacity from 400-1,000 TEUs which when combined with

their 2,900 containers enables them to offer the entire range of shipping options [28, 30]. The

structure of ICG is displayed graphically in the Appendix E.


Chapter 1: Introduction - 1.10 Rubber Tyred Gantry Cranes (RTGs) 31

1.10 Rubber Tyred Gantry Cranes (RTGs)

As previously detailed, the main area of port operations where improvements regarding costs,

environmental issues and operational efficiency are possible is in container handling, particularly

through the optimisation of equipment that consumes excessive quantities of fossil fuels. This was

further refined to RTGs as they both consume vast amounts of fuel and offer the potential for energy

recovery. In the Irish context, many readers will be familiar with two of the most famous rail

mounted gantry cranes (RMGs) in the world, located in the Harland and Wolff shipyard in Belfast,

the cranes named Samson and Goliath were used for the construction of the RMS Titanic. Each crane

has a 140 metre span with a combined lifting capacity of over 1,600 tonnes to a height of over 70

metres [33, 34].

Figure 1.10.1: Gantry cranes “Samson and Goliath”

The gantry crane currently credited with lifting the heaviest weight in the world is named ‘Taisun’

and is located in the Yantai Raffles shipyard in China. In 2008, ‘Taisun’ lifted a barge ballasted with

water with a weight of 20,133 tonnes [35]. This crane operates in a dry dock over 14 metres deep

and can facilitate loads up to 120 metres in width up to a lift height of 83 metres. Taisun’s

construction cost approximately $40 million, some of its notable projects are presented in the

Appendix F [36]. As opposed to being stationary or rail mounted, RTGs have the freedom to traverse



their work area due to being mounted on rubber tyres. RTGs are mobile and can derive their power

from a variety of sources, however RTGs are typically powered by an on-board diesel engine coupled

to an alternator. This enhances the cranes freedom of movement and also allows them to be used

temporarily at a location and then relocated as necessary, or to be moved in the event of dangerous

weather conditions. RTGs come in a variety of different lifting and hoisting arrangements depending

on their use case. Hence, RTGs have found uses lifting heavy loads in warehouses, manufacturing

facilities and both rail and shipping yards as shown below [37].

Figure 1.10.2 Various Crane uses



Figure 1.10.3: RTG diagram

Table 1.10.1 RTG diagram

In general, an RTG is a crane with rubber tyred wheels at the base of the vertical upright beams

(labelled C in the above figure) which enables the entire crane to traverse, this is known as gantry

travel [37]. The crane uses a hoist fitted with a hook or specialised lifting mechanism to raise and

lower objects for either general lifting or for a particular role. The hoisting system consists of cables

running over and around sheaves that are connected to one or more winches and is fitted to a

platform called a trolley. The trolley is supported between the horizontal bridges or gantries of the

Component Direction

A Trolley 1 Horizontal trolley motion (trolleying)

B Gantries/Bridge 2 Complete gantry motion (gantry travel)

C Uprights 3 Vertical spreader motion (hoisting)

D Spreader

E Hoist



RTG [37]. As shown by direction 1 labelled in the above figure, the trolley and hence the hoist can

move horizontally along rails fitted onto the cranes gantries to enable lateral motion of the empty or

loaded hoist, this is known as trolleying [33]. The gantries are in turn supported by the cranes

uprights. The horizontal motion of the trolley, and hence the hoist, along the bridges combined with

the vertical motion of the lifting mechanism derived from the hoist and the overall motion of the

entire crane results in three axes of motion for the lifting mechanism [33]. This level of freedom

enhances the suitability of RTGs for a wide range of industries as shown above.

In the case of this project, focussing on a port environment, RTGs are used for the loading and

unloading of freight vehicles and for the positioning of shipping containers within the container stack

of a shipping terminal [38, 39]. This requires the standard lifting mechanism to be replaced with a

lifting device called a spreader, shown below, which enables the crane to securely lift shipping

containers to heights of up to 21 metres in a stable manner often against poor weather conditions

and high winds of up to 72 kilometres per hour (km/h) [40, 41].

Figure 1.10.4: Hoisting mechanism known as a spreader



In order to maintain the containers in a safe and level position during lifting an extra device is often

incorporated into the hoisting mechanism. This device employs additional cables to prevent the

container from swaying due to high winds or motion of the trolley or the RTG as shown below.

Figure 1.10.5: Hoisting mechanism for spreader

While the spreader of a typical RTG weighs approximately ten tonnes, the hoist is capable of lifting

containers with a weight of up to fifty tonnes at a rate of approximately one container per minute,

depending on the hoisting speed and the distance to be travelled [38, 39]. The nature of the lifting

operations, shown in the figure overleaf, requires peak power output for very short durations when

the container is accelerated from rest to the steady hoisting speed. Once the desired height has

been achieved, a constant power output is provided to slowly trolley the container to its destination.

Finally power is dissipated as the container is lowered [39].



Figure 1.10.6: Sample container handling operation

To meet the high peak power output required, an RTG typically uses a powertrain comprised of a

diesel engine rated between 350 kilowatts (kW) and 675 kW paired to an electrical generator in the

form of a 3-phase alternator [41]. Such a combination of a diesel engine and generator is commonly

referred to as a genset and is shown in the below image [38].

Figure 1.10.7: RTG diesel genset



The genset provides the electrical power for the individual motors responsible for hoisting, trolleying

and gantry travel as shown in the accompanying diagram [38, 42].

Figure 1.10.8: Diagram of genset connection to hoist

This standard configuration operates without an ESS and hence the power demand, including all

peaks, must be entirely met by the diesel engine. Furthermore, any energy regeneration potential

must be dissipated resulting in an unnecessarily high fuel requirement [42]. This leads to the

secondary aim of this project – to determine the magnitude of energy savings that could be achieved

if energy recovery and storage technology was employed. This topic is in line with recommendations

from the European Commission to reduce fuel consumption and subsequent GHG emissions of RTGs

[43].


Chapter 1: Introduction - 1.12 Project Objectives 38

1.11 Overall Project Aim

For the many reasons outlined above, the overall aim of this project is to develop a computer based

calculation scheme to estimate the energy usage by RTGs during standard daily operations. The

mathematical model must allow for future revisions or updates. Visual aids were included to verify

with the user that the specified operating conditions were correct. The magnitude of potential

energy savings made possible through energy saving or recovery technology were determined.

1.12 Project Objectives

The objectives of this project were as follows;

1. Perform a literature review to gain an understanding of previous work and background material

relating to this topic.

2. For existing energy recovery and storage technology, compare parameters to determine which would

be most suitable for use with RTGs.

3. Determine the important components on an RTG which relate to the potential to regenerate energy.

4. Determine the efficiencies of these critical components.

5. Use the efficiencies to develop a calculation scheme in Microsoft Excel, using Visual Basic for

Applications (VBA), to calculate the energy used by a crane during typical operations.

6. Create a user interface to allow for the error-proof entry of data into the calculation scheme.

7. Develop code using VBA to fully automate the data entry process and include all possible data.

8. Determine the quantity of energy that is regenerated in the hoist motor through the various lowering

events.

9. Convert this energy quantity to equivalent fuel energy input.

10. Calculate the potential reduction in fuel consumption and corresponding emissions.

11. Convert the volume of fuel to financial quantities based on approximate fuel costs.


Chapter 1: Introduction - 1.13 Report Layout 39

1.13 Report Layout

Chapter 1 sets the context of the project by introducing the importance of ports in Ireland,

particularly Dublin Port. The impact of Ports on the environment is also introduced with emphasis on

container handling equipment.

The overall aim of the project is outlined, as are the objectives.

Chapter 2 presents the literature review where the operation of generators, motors and ESSs are

explored. A selection of use cases for ESSs are examined with the aim of determining the suitability

of ESSs to RTGs. The operation of the most usual ESS are explored. Alternative means of reducing

fuel consumption and emissions are discussed.

Chapter 3 contains the methodology undertaken to complete the project. Including the means of

selecting the chosen ESS and how the problem was tackled.

Chapter 4 contains the results of the calculation scheme and the calculations arising from the

equations developed in chapter 3.

Chapter 5 presents a discussion of the results obtained through the use of the calculation scheme

and a discussion of alternatives as researched in the literature review.

Chapter 6 presents the conclusions of the project.

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