George Aggidis -Tidal Eneergy Review

Lancaster University

Renewable Energy Group

George A. Aggidis

Director



& Fluid Machinery Group

[email protected]

Wednesday 24 March 2010

The Irish Sea's

Tidal Power

Potential

including the Dee

Estuary

Wales

North

Network

http://www.lancs.ac.uk/

mailto:[email protected]

http://www.theiet.org/



OVERVIEW

• Introduction

• Tidal Resource

• Present state of the art,

technology

• Tidal range projects

• Environmental implications

• UK and NW Tidal range

projects including Dee

• Conclusions


http://derek4messiah.files.wordpress.com/2009/08/earth.jpg



Introduction

• The Irish Sea's potential for electricity generation from tidal power is substantial, comparable with that of the Bristol Channel.

• The presentation will touch on all major schemes being considered and developed, including the potential for the Dee Estuary.

3




CENTRIPETAL

GRAVITATIONAL FORCE

GRAVITATIONAL & CENTRIPETAL

Tides Governed by Earth-Moon-

Sun




Neap & Spring Tides

Lunar Month = 29.53 Days

• Neap Tide ( ¼ Moon & ¾ Moon)

• Spring Tide (Full Moon & New Moon)




Earliest Tidal Research

Dates back to ~ 350BC

AristotleLyceum

Ancient Greece

Evripos Straits

PytheasMassalia

Ancient Greece

ARISTOTLE Earliest reference on the world on ocean

research

PYTHEASProduced accounts of tidal movements

Atlantic Ocean


http://images.google.co.uk/imgres?imgurl=http://www.geocities.com/joek_bm/images/matematica/biografias/foto_matematicos/Aristotle.jpg&imgrefurl=http://www.geocities.com/joek_bm/images/matematica/biografias/aristotle.htm&usg=__WeTFB1fcAY9hVclo_hJ7_PTj39Q=&h=326&w=268&sz=18&hl=en&start=6&um=1&tbnid=8zDm7lVweFU5-M:&tbnh=118&tbnw=97&prev=/images?q=aristotle&um=1&hl=en&sa=G

http://images.google.co.uk/imgres?imgurl=http://www.athropolis.com/arctic-facts/people/pytheas.gif&imgrefurl=http://www.athropolis.com/arctic-facts/fact-pytheas.htm&usg=__y9TfX1s4TJzH5QErpydYBrFz948=&h=154&w=161&sz=13&hl=en&start=9&tbnid=M__OPzalMFT6MM:&tbnh=94&tbnw=98&prev=/images?q=pytheas&gbv=2&hl=en&sa=G



Historical development

(to the 1970s)

Salter Edinburgh Duck

Edinburgh University

The Lancaster Flexible Bag


Prof Michael French


Prof Steven Salter

Edinburgh University

• La Rance Tidal Barrage

France

• Location: Saint Malo,

Brittany

• D=5,350mm

• n=93.75 rpm

• H=11m

• P=10 MW

• 24 Units (Alstom)

• Contract year: 1967


http://images.google.co.uk/imgres?imgurl=http://www.mech.ed.ac.uk/research/wavepower/duck/duck%20SH%20rig%20big.jpg&imgrefurl=http://www.mech.ed.ac.uk/research/wavepower/&h=1167&w=1750&sz=275&hl=en&start=13&um=1&tbnid=bJIEf4G7AwfpUM:&tbnh=100&tbnw=150&prev=/images?q=Salter,+S+H&svnum=10&um=1&hl=en&rls=DNUK,DNUK:2007-05,DNUK:en&sa=N



World & UK tidal resource

• Worldwide tidal energy potential about 500-1000TWh/year

• UK is estimated to hold 50TWh/year

• UK represents 48% of the European resource

• Few sites worldwide are as close to electricity users and the transmission grid as those in the UK

• Department of Energy (DoEn) studies in the 1980s, identified 16 estuaries where tidal barrages should be capable of procuring over 44TWh/year

• The bulk of this energy yield would accrue from 8 major estuaries, in rank order of scale, the Severn, Solway Firth, Morecambe Bay, Wash, Humber, Thames, Mersey and Dee

8




Global Distribution of Tidal Range

9




UK Resource

Key to map

Proudman

Oceanographic

Laboratory




Atlas of UK Marine Renewable Energy Resources: Atlas Pages

A Strategic Environmental Assessment Report September 2004

NW

Resource




Tidal Current

Energy Resource

• Tides depend on position of moon and sunin relation to the earth – provide a highly predictable source of power

• 18TWh/year technically extractable tidal current resource in UK – could meet 3-5%of energy demand1

• Power extracted from kinetic energy of flowing water:

P= ½ ρAU3

•Water 800 times denser than air, so require lesser flow rates

1 Carbon Trust. “Future Marine Energy”. January 2006.

2 DTI. “Atlas of UK Marine Energy Resources”. 2004

Marine Current Turbines Ltd (MCT) Seagen 1.2 MW




Peak Flow for a Mean

Spring Tide (2)



Spring tidal currents around

double neap

Tidal currents vary with depth




Mean Spring Tidal Power

Density (2)






Tidal Current

Turbine Technologies

Four main types of Tidal

Energy Convertors (TEC)

• Horizontal Axis

– Rigidly mounted

– Floating and Semi-

Submerged

• Vertical Axis

• Hydrofoil

– Oscillating

– Translating

• Venturi Systems

• Other

Open Hydro




• This device extracts energy

from moving water in much

the same way as wind

turbines extract energy from

moving air.

• Devices can be housed within

ducts to create secondary

flow effects by concentrating

the flow and producing a

pressure difference

Horizontal axis turbines




Horizontal Axis TurbinesRigidly Mounted

Tidal Generation (UK)

http://www.tidalgeneration.co.uk

KESC Bowsprit Generator /

KESC Tidal Generator (USA)

http://www.kineticenergysystems.comFree Flow Turbine (USA)http://www.verdantpower.com

Kuroshio Ocean Turbine (TW)

http://www.iam.ntu.edu.tw/

Rotech Tidal Turbine (UK)http://www.lunarenergy.co.uk/

Clean Current Tidal Turbine (Canada)http://www.cleancurrent.com

Voith Siemens Hydro (Germany)

http://www.hydro.org/news/Weilepp.%20Wave%20Power.pdf


http://www.tidalgeneration.co.uk/

http://www.tidalgeneration.co.uk/

http://www.kineticenergysystems.com/

http://www.verdantpower.com/

http://www.iam.ntu.edu.tw/

http://www.verdantpower.com/gallery2/main.php?g2_itemId=141

http://www.lunarenergy.co.uk/

http://www.cleancurrent.com/

http://www.hydro.org/news/Weilepp. Wave Power.pdf





Horizontal Axis Turbines

Floating & Semi- Submerged

Devices

Underwater Electric Kite (USA)

http://www.uekus.comModril (Norway)

http://www.statkraft.com

Hydro-Gen (France)

http://www.hydro-gem.fr

OCGen (USA)

http://www.oceanrenewablepower.com


http://www.uekus.com/

http://www.statkraft.com/

http://www.hydro-gem.fr/



http://www.oceanrenewablepower.com/




Rigidly Mounted

The Blue Concept (Norway)

http://www.e-tidevannsenergi.comSwanturbines (UK)

http://www.swanturbines.co,uk/

Hydrohelix Turbine (France)

http://www.hydrohelix.fr/

Open Centre Turbine (Ireland)

http://www.openhydro.com

Tocardo (Nederlands)

http://www.tocardo.com

Seaflow (UK) & Seagen (UK)

http://www.marineturbines.com


http://www.e-tidevannsenergi.co.uk/



http://www.swanturbines.co,uk/

http://www.hydrohelix.fr/

http://www.openhydro.com/

http://www.tocardo.com/

http://www.marineturbines.com/




Floating & Semi- Submerged

Devices

Evopod (UK)

http://www.oceanflowenergy.com

SRTT (UK)

http://www.scotrenewables.com

TidEl (UK)

http://www.smdhydrovision.com

Semi submersible Turbine (UK)http://www.tidalstream.co.uk

CORMAT(UK)

[email protected]


http://www.oceanflowenergy.com/

http://www.scotrenewables.com/

http://www.smdhydrovision.com/

http://www.tidalstream.co.uk/




• This device extracts energy

from moving water in a

similar fashion to the

horizontal axis turbines,

however the turbine is

mounted on a vertical axis.

Vertical axis turbines




Vertical Axis Turbines

Proteus (UK)

http://www.neptunerenewableenergy.com

Polo (UK)

http://www.mech.ed.ac.uk

Blue Energy (Canada)

http://www.bluenergy.com

Gorlov Helical Turbine (USA)

http://www.gcktechnology.com

Kobold Turbine (Italy)http://www.pontediarchimede.it

EnCurrent Turbine (Canada)

http://www.newenergycorp.ca


http://www.neptunerenewableenergy.com/

http://www.mech.ed.ac.uk/

http://www.bluenergy.com/

http://www.gcktechnology.com/

http://www.pontediarchimede.it/

http://www.newenergycorp.ca/



Vertical Axis Turbines

Water Turbine (Norway)

http://www.anwsite.com

Lancaster University (UK)

http://www.engineering.lancs.ac.uk/REGROUPS/LUREG/home.htm

Water Power Industries WPI (Norway)

http://www.wpi.noAlternative Hydro Solutions (Canada)

http://www.alternativehydrosolutions.com


http://www.anwsite.com/

http://www.engineering.lancs.ac.uk/REGROUPS/LUREG/home.htm

http://www.wpi.no/

http://www.alternativehydrosolutions.com/



• A hydrofoil attached to an

oscillating arm and the motion is

caused by the tidal current flowing

either side of a wing, which results

in lift.

• This motion can then drive fluid in a

hydraulic system to be converted

into electricity.

Oscillating Hydrofoil




Hydrofoils

Pulse Generator (UK)http://www.pulsegeneration.co.ukBioStream (Australia)

http://www.biopowersystems.com

Stingray (UK)

http://www.engb.com

Harmonica (Norway)

http://www.tidalsails.com

Aquanator

http://www.atlantisresourcescorporation.com


http://www.pulsegeneration.co.uk/

http://www.biopowersystems.com/

http://www.engb.com/

http://www.tidalsails.com/

http://www.atlantisresourcescorporation.com/



• By housing the device in a duct,

this has the effect of concentrating

the flow past the turbine.

• The funnel-like collecting device

sits submerged in the tidal current.

• The flow of water can drive a

turbine directly or the induced

pressure differential in the system

can drive an air-turbine.

Venturi Effect




Venturi Devices

Gentec Venturi (New Zealand)http://www.greenheating.com

Hydro Venturi (UK)

http://www.hydroventuri.com

Spectral Marine Energy Converter (UK)

http://www.verderg.com


http://www.greenheating.com/

http://www.hydroventuri.com/

http://www.verderg.com/



• This covers those

devices with a unique

and very different

design to the more

well-established types

of technology or if

information on the

device’s characteristics

could not be

determined.

Other Designs




SuperGen Marine II Energy

Research Consortium

• WS1: Numerical and physical convergence

• WS2: Optimisation of collector form and

response

• WS3: Combined wave and tidal effects

• WS4: Arrays, wakes and near field effects

• WS5: Power take-off and conditioning

• WS6: Moorings and positioning

• WS7: Advanced control of devices and

network integration

• WS8: Reliability

• WS9: Economic analysis of variability and

penetration

Generic Research

MARINE II




30

University scale

1/100 testing




At NaREC in NE England there is a 1/10th

scale wave and tidal test facility

UK marine energy

infrastructure




• 5 Berths 10-50m

• Grid connected

• 3.5m/s flow

• Sheltered area

EMEC Tidal Test Site

© EMEC

UK marine energy infrastructure




•We have come a long way from the mid 1970s

•We have moved from artists’ impressions to devices at sea generating into the electricity network

The Birth of an Industry


http://images.google.co.uk/imgres?imgurl=http://www.mech.ed.ac.uk/research/wavepower/duck/duck%2520SH%2520rig%2520big.jpg&imgrefurl=http://www.mech.ed.ac.uk/research/wavepower/&h=1167&w=1750&sz=275&hl=en&start=13&um=1&tbnid=bJIEf4G7AwfpUM:&tbnh=100&tbnw=150&prev=/images%3Fq%3DSalter,%2BS%2BH%26svnum%3D10%26um%3D1%26hl%3Den%26rls%3DDNUK,DNUK:2007-05,DNUK:en%26sa%3DN



•Open Hydro 250 kW open flow tidal current turbine in Orkney connected to the network

•Marine Current Turbines SeaFlow has been operating for three years and is rated 300 kW

•Marine Current Turbines installed SeaGen – a twin propeller device rated 1200 kW and connected to the network

Device Development

© OpenHydro

© MCT© MCT




MARINE

MW to market

£/MW R D D D

Scottish Enterprise

The UK commitment to the

marine energy provides this

type of support for sectoral

development

UK marine energy

infrastructure

Research/Development/Demonstration/Deployment


http://www.hie.co.uk/



The UKERC Road Map identified research priorities to establish the industry as:

– Test facilities– Moorings and Foundations– Resource modelling– Device modelling– PTO and control– Installation and O&M– Survivability– Electrical Power infrastructure and technology– Economics & Policy– Standards & Life cycle analysis

UK Energy Research Centre

Future Challenges

for the Industry




Tidal Stream

• Tidal stream offers predictable renewable energy

• Existing commercial developments demonstrate the possibilities

• Rapidly growing sector

• Offers considerable advantage over other renewables

• There exists significant potential for new inshore devices

• The UK requires a varied distributed energy network to remain competitive




• The Northwest of England has the capability to provide at least 5% of UK power through renewable energy tidal schemes; around half the Northwest’s total energy needs

• The NWTEG brings together the Northwest’s four pipeline tidal energy projects & key stakeholders to raise the profile of the sector and disseminate best practice

• 95 plus members

• Chaired and facilitated by NWDA




Tidal Range

Technology

• Across Estuaries/Rivers/Islands

• Manmade pools




Barrage Tidal Energy

• The energy available from a barrage is dependent on the volume of water.

The potential energy contained in a volume of water is:

• where:

• h is the vertical tidal range,

• A is the horizontal area of the barrage basin,

• ρ is the density of water = 1025 kg per cubic meter (seawater varies

between 1021 and 1030 kg per cubic meter) and

• g is the acceleration due to the Earth's gravity = 9.81 meters per second

squared.

• The factor half is due to the fact, that as the basin flows empty through the

turbines, the hydraulic head over the dam reduces. The maximum head is

only available at the moment of low water, assuming the high water level is

still present in the basin.




Terminology

• The relative scale of turbine installation adopted from the Severn Tidal Group studies formed the basis of the DoEn’s follow-up studies, namely ebb mode being favoured with turbine numbers roughly compatible with extracting about 50% of the available ebb-phase energy.

• This results in tidal levels in the estuary basins dropping only to mean sea level or thereabouts, and in this respect is consistent with the theoretical approach put forward by Prandle.

• Schemes with these characteristics are referred to as ‘1xDoEn’ turbine installations.

41




Ebb, Flood, Dual Generation

• Delay the natural motion of the tidal flux as sea level changes:

• Holding back the release of water as tide level subsides under ‘ebb generation’ so that ‘head’ (water level) difference is sufficient for turbine operation

• Deferring the entry of rising tidal flow to the inner estuary basin for ‘flood generation’

• or ‘dual mode’, a combination of both

– Each mode has some restricting effect, so reducing the range of tidal variation within the basin, with ebb generation solutions uplifting mean water levels, flood generation reducing mean levels and dual mode operation resulting in little change

42




Double regulated bulb turbine Hill-Chart

(Escher Wyss)

43




• Existing tidal references world wide:

– La Rance, France, 1967

• Alstom

– Annapolis, Canada, 1980

• Andritz VATECH Hydro

– Sihwa, South Korea, 2005

• Andritz VATECH Hydro

Tidal Range

References

La Rance, France Bay of Fundy, Canada

Bird's eye view of Sihwa, South Korea tidal power plant

to be completed in 2010 © DAEWOO




La Rance Tidal Plant

France

La Rance Tidal Barrage Brittany, France

– Completed 1966/67

– 8 m tidal range

– 330 m long

– 22 km2 basin

– 24 x 5.4 m turbines

– 240 MW total capacity




La Rance Tidal Barrage

France

• Location: Saint Malo, Brittany

• D=5,350mm

• n=93.75 rpm

• H=11m

• P=10 MW

• 24 Units





Annapolis Tidal Plant

Canada

• Location: Bay of Fundy

• D=7,600mm

• n=50 rpm

• H=7.1m

• P=19.9 MW

• 1 Unit





Sihwa Tidal Plant

South Korea

• Location: Sihwa Tidal Plant

• D=7,500mm

• n=64.3 rpm

• H=5.8m

• P=26 MW

• 10 Units

• Contract year: 2005Bird's eye view of Sihwa tidal power plant

to be completed in 2010 © DAEWOO




(A. Schwab/B. Hindelang Dec. 08)

PROJECT BACKGROUND:

• An existing dam built in 1994 (agriculture, reclamation of land)

• Industrial and biological pollution→ return to natural exchange of water

• Korea is investing into renewable energies (Kyoto-Mechanism): from 1.4 % to 5 % in 2011 & reducing oil imports

• Total project costs: around 250 million USD

• Specific Investment Costs:250 million USD / 260 MW ≈ 1 million USD / MW

SIHWA TIDAL

Largest tidal power plant

in the world




(A. Schwab/B. Hindelang Dec. 08)

Purpose of Sihwa power plant

• Improve water quality inside the lake

• Power generation

Plant Data

• Mean Tidal Range : 5.6m

• Spring Tidal Range : 7.8m

• Basin Area : 43km2

• Generation Method : One-way during flood tide

• Installed Capacity : 250MW (Horizontal Axial Bulb Unit)

• Estimated Annual Output : 553 GWh

SIHWA TIDAL

Largest tidal power plant

in the world




Other Systems

Tidal Delay (Australia)

http://www.woodshedtechnologies.com.au

Tidal Lagoons (UK)

http://www.tidalelectric.com

Tidal ‘Reef’ Barrage (UK)

http://www.evans-engineering.co.uk


http://www.woodshedtechnologies.com.au/

http://www.tidalelectric.com/

http://www.evans-engineering.co.uk/





• Modification of resource

• Alteration of physical environment

• Robustness of device (climate change)

• Connection to land

• Impact on flora and fauna

– Birds, mammals, fish, invertebrates

– Habitats

• Terrestrial impacts

Environmental Issues

Anglersnet.co.uk


http://upload.wikimedia.org/wikipedia/commons/c/c4/Bristol.zoo.common.eider.arp.jpg

http://upload.wikimedia.org/wikipedia/commons/5/51/Haematopus_ostralegus_He.jpg



Geographic variability

• Match device to opportunity

• Interaction between location and form of land

• Importance of dynamics

• Need to recognise risks & barriers





Barriers

• Economics

• Environmental change

• Social disruption

• Electricity grid connection





• Siltation

• Change in tidal regime

• Whole system (terrestrial & marine)

• Ecology




Environmental constraints

• Habitats

– EU Habitats Directive

– Designated landscapes (RAMSAR, SAC, SPA, etc)

• Species

– Birds

– Fish

– Others (marine mammals, terrestrial plants and animals)




Environmental Overview

• A degree of environmental modification is, therefore, inevitable, but

• this does not necessarily imply serious degradation from a physical or ecological perspective, though

• issues related to protection of habitats inevitably need to be confronted.

57




58

IET – Tidal Power




59

UK Tidal Schemes - Severn




UK Tidal Schemes - Other

60




Map of proposed optionsSevern Tidal

Project




Map of proposed shortlistSevern Tidal

Project




Tidal Lagoon

Proposed Location




Demonstration Scheme




Mersey

Irish Sea

Dee

8.5m

5.5m

7.46m

?

?

11 hours

10 hours

Ribble

Morecambe

Solway

Wyre

The Northwest of England has a significant tidal energy resource, with

capability to provide at least 5%of UK power through tidal energy.




66

The Dee Estuary Aber Dyfrdwy

• River Dee flowing into Liverpool Bay

• The estuary starts near Shotton after a five miles (8 km) 'canalised' section

• The river soon swells to be several miles wide forming the boundary between the Wirral Peninsula in north-west England and Flintshire in north-east Wales


http://upload.wikimedia.org/wikipedia/commons/4/46/Dee_estuary2.jpg



Potential Dee Barrage alignment & extended

Dee–Wirral lagoon

67

• Installing 2-3 times the number of turbines theoretically doubles the total energy capture, at unit costs around 10p/KWh (Dee)

• The SDC report shows 10p/KWh for the unit cost of energy from offshore wind installations which receive strong backing at present

(Burrows, 2009)




2-D ADCIRC modellingFlow simulations

(Burrows, 2009)

68

The whole grid

Upper Irish Sea

Dee estuary with barrages in place




Dee Estuary 40x21MW 8m turbines

40x8mx12m sluices

• Operating Modes

• Ebb 1.35 TWh

• Dual 1.30 TWh

• Flood 0.78 TWh

(Burrows, 2009)

External tidal elevation & reduced basin

level variations (m) against time (days)




Dee – Power outputs and basin/tide levels

70(Burrows, 2009)




Dee – Annual Energy vs turbine numbers

71(Burrows, 2009)




Estimated unit cost (p/kWh) for Dee schemes with

different number of turbines

72

(Burrows, 2009)




Dee with increasing installed capacity

73

(Burrows, 2009)




0-D Modelling Summary

74(Burrows, 2009)




Hatton, 2009

Mersey




Hatton, 2009




Mersey Tidal Power Feasibility study 2010

• The feasibility study is being led jointly by a consulting team comprising Scott Wilson, Drivers Jonas and EDF, on behalf of Peel Energy and the Northwest Regional Development Agency (NWDA).

• The study aims to identify a tidal power scheme that meets three prime objectives:

• The tidal power scheme has to be capable of generating a meaningful amount of electricity at a price that the country can afford;

• The direct impacts on the environment, shipping, local businesses and communities must be kept to acceptable levels (in determining their acceptability, measures may need to be provided to mitigate or compensate for the impacts); and

• The tidal power scheme should be to the maximum possible benefit of the region in a socio-economic and environmental sense.

77




Mersey Tidal PowerFour Technologies

• The four technologies selected are:

• A tidal barrage incorporating conventional tidal turbines similar to those routinely used in low head hydroelectric power applications;

• A tidal power gate – which could perform as a very low-head barrage –containing a grid of specially designed, smaller tidal turbines This is the kind of technology used to produce power from, for example, reservoir spillways and sluices;

• A tidal fence – a means of capturing energy from the natural or constrained velocity of the tidal flow – with either horizontal- or vertical-axis turbines designed for generating electricity in open streams; and

• An alternative tidal fence based on a new proprietary device that concentrates the energy contained in a large body of slow-moving water into a smaller body of fast-flowing water using the Venturi effect.

• The developers warn that the list may be revised and developed as the study proceeds and further information becomes available.

78




Mersey Tidal PowerNext steps

• The Mersey Tidal Power project has completed in March 2010 the first stage (shortlist down to four technologies) of a major feasibility study designed to select a preferred tidal power scheme for Mersey Estuary, North West England.

• Next step in the progress of the feasibility study is to formulate an acceptable scheme on which to base a planning application by the end of 2011.

79




Mersey – Next steps

• In the next stage of the feasibility study, indicative sites within the estuary where the different tidal power technologies could be best deployed will be identified and possible scheme layouts established.

• There will be an economic analysis that looks at the likely energy yields of the different tidal power schemes set against their anticipated construction and operating costs.

80




RIVER WYRE

Southern barrage

position

Sand and

Mud flats

Salt marshes

Edward Greenwood, Wyre Tidal Energy

Wyre




AN IMPRESSION OF BARRAGES ON THE RIVER WYRE (SOUTHERN AND JUBILEE)

Material dredged out for power

generating barrages is used to

reclaim land and make a deep water

shipping terminal

River dredged to

form access harbour

to the lagoon

FLEETWOOD

A barrage on the River Wyre has a potential output of 90MW. Due to its unique location the

opportunity exists for a Compressed Air Energy Storage Plant (CAES) by injecting compressed

air into some of the redundant salt caverns in the area. The system can eliminate the problems

associated with an intermittent power source and add to the economic viability of the project.

Edward Greenwood, Wyre Tidal Energy




Morecambe Bay

Bridge Proposal




Bridge Across The Bay

• Bridge hosting/supporting

renewable energy technologies

• Tidal, wind and solar being

investigated

• Free stream vertical axis

tidal turbines favoured

• Target to extract 200MW

• Aims to have minimal environmental

impact and maximum socio/economic

benefit

Morecambe Bay




Solway




Solway Firth EnergyFeasibility Study 2010

Halcrow RSK Mott MacDonald

86

Catterson, 2009




Multi Functional Infrastructure including

Power Generation• Barrage schemes are unique amongst power installations, being

inherently multi-functional infrastructure, offering flood protection, possible road and rail crossings and significant amenity/leisureopportunities, amongst other features.

• Thus, a fully holistic treatment of overall cost-benefit is imperative for robust decision-making. It is suggested that, to date, this position has been inadequately addressed in the formulation of energy strategy, especially in respect of barrages’ potential strategic roles in flood defense and transportation planning.

• It follows, therefore, that apart from the direct appraisal of energy capture, other complementary investigations must be sufficiently advanced to enable proper input in decision-making in respect of these ‘secondary’ functions, as well as the various potentially adverse issues, such as sediment regime change, impact on navigation and environmental modification. 87




Multi Functional Infrastructure

Power

Generation

Flood

Risk

Transport

Tourism

Job

Creation

Water

Habitat &

SpeciesLand

Use

Fisheries

Cultural

Heritage




Conclusion

• The UK has substantial potential of tidal renewable energy generation, to about 20% of present UK demand

• Eight major estuaries capable of meeting at least 10% of present electricity demand, employing fully proven technology

• Achievable, under favourable UK Treasury discount rates

• The UK has tidal stream practicable potential to about 5% of present electricity demand

• NW potential from barrages at least 5% of present electricity demand

• Tidal barrages in the estuaries of the NW capable of meeting about 50% of the region’s electricity needs

• The Challenge is for engineers and scientists to deliver UK’s marine renewable energy targets

• The Opportunity is for the UK to deliver renewable energy with minimal environmental impact

89




George A. Aggidis

Director



& Fluid Machinery Group

[email protected]

The Irish Sea's Tidal Power

Potential including the Dee

Estuary

Wales

North

Network Thank you



http://www.theiet.org/

Documents

George Aggidis -Tidal Eneergy Review