Master Class on innovative tidal energy techniques

Transcription

PRO-TIDE
MASTER CLASS ON INNOVATIVE TIDAL ENERGY TECHNIQUES
VERSION 2.0 - 23 DECEMBER 2013
Toon Goormans, Steven Smets, Roeland Notelé
Colophon
International Marine & Dredging Consultants
Address: Coveliersstraat 15, 2600 Antwerp, Belgium
: + 32 3 270 92 95
: + 32 3 235 67 11
Email: [email protected]
Website: www.imdc.be
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Waterwegen en Zeekanaal nv
IMDC nv
Master Class Innovative Tidal Energy Techniques
Overview of available technologies
Table of Contents
0
INTRODUCTION .............................................................................................................................................. 10
0.1
PRO-TIDE .................................................................................................................................................... 10
0.2
AIM OF THE STUDY .................................................................................................................................... 10
0.3
STRUCTURE OF THE REPORT ................................................................................................................. 10
0.4
DISCLAIMER ................................................................................................................................................... 10
1
TIDAL ENERGY TECHNIQUES ...................................................................................................................... 11
1.1
TIDAL CURRENT ENERGY CONVERTORS ............................................................................................................ 11
1.1.1
Horizontal axis marine current turbines using lift forces ...................................................................... 12
1.1.1.1
Open HAMCTs ................................................................................................................................ 12
1.1.1.1.1
Alstom (previously Tidal Generation Ltd) ........................................................................................ 12
1.1.1.1.2
Andritz Hydro Hammerfest .............................................................................................................. 13
1.1.1.1.3
Aquaphile sarl ................................................................................................................................. 14
1.1.1.1.4
AquaScrew bvba ............................................................................................................................. 15
1.1.1.1.5
Atlantis Resources Corporation ....................................................................................................... 16
1.1.1.1.6
Hydra Tidal ...................................................................................................................................... 17
1.1.1.1.7
Nautricity Ltd ................................................................................................................................... 18
1.1.1.1.8
Oceanflow Energy Ltd ..................................................................................................................... 19
1.1.1.1.9
SABELLA SAS ................................................................................................................................ 20
1.1.1.1.10
Scotrenewables Tidal Power Ltd ..................................................................................................... 21
1.1.1.1.11
Siemens (previously Marine Current Turbines Ltd) ......................................................................... 22
1.1.1.1.12
SMD ................................................................................................................................................ 23
1.1.1.1.13
Swanturbines .................................................................................................................................. 24
1.1.1.1.14
Tidal Energy Ltd (originally Tidal Hydraulic Generators Ltd) ........................................................... 25
1.1.1.1.15
TidalStream Ltd – SCHOTTEL GmbH ............................................................................................ 26
1.1.1.1.16
Tocardo International BV ................................................................................................................ 28
1.1.1.1.17
Verdant Power Inc........................................................................................................................... 29
1.1.1.1.18
Voith ................................................................................................................................................ 30
1.1.1.2
Ducted HAMCTs ............................................................................................................................. 31
1.1.1.2.1
Clean Current Power Systems Inc. ................................................................................................. 31
1.1.1.2.2
Lunar Energy................................................................................................................................... 32
1.1.1.2.3
Open Hydro ..................................................................................................................................... 33
1.1.1.2.4
UEK Corporation ............................................................................................................................. 34
1.1.2
Cross axis marine current turbines ...................................................................................................... 35
1.1.2.1
Open VAMCTs ................................................................................................................................ 35
1.1.2.1.1
Aquascientific .................................................................................................................................. 35
1.1.2.1.2
Comarent ........................................................................................................................................ 35
1.1.2.1.3
Edinburgh Designs Ltd .................................................................................................................... 36
1.1.2.1.4
IHC Merwede – Bluewater .............................................................................................................. 36
1.1.2.1.5
INSEAN and Ponte di Archimedi S.p.A. .......................................................................................... 38
1.1.2.2
Ducted VAMCTs ............................................................................................................................. 39
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1.1.2.2.1
Blue Energy Canada Inc. ................................................................................................................ 39
1.1.2.2.2
Deepwater Energy BV ..................................................................................................................... 40
1.1.2.2.3
HydroQuest ..................................................................................................................................... 41
1.1.2.2.4
Tidal Energy Pty Ltd ........................................................................................................................ 42
1.1.2.3
Horizontal cross-axis turbines ......................................................................................................... 43
1.1.2.3.1
Kepler Energy Ltd. .......................................................................................................................... 43
1.1.2.3.2
OceanRenewable Power Company ................................................................................................ 44
1.1.2.4
Marine current turbines using drag forces ....................................................................................... 45
1.1.2.4.1
Atlantisstrom GmbH & CoKG .......................................................................................................... 45
1.1.2.4.2
Eco Hydro Energy Ltd. .................................................................................................................... 46
1.1.2.4.3
Hales Water Turbines Ltd................................................................................................................ 47
1.1.2.4.4
Neptune Renewable Energy Ltd. .................................................................................................... 48
1.1.2.4.5
S.A. Rutten ...................................................................................................................................... 49
1.1.2.4.6
Sea Power International AB ............................................................................................................ 49
1.1.2.4.7
Tideng ............................................................................................................................................. 50
1.1.2.4.8
Other ............................................................................................................................................... 50
1.1.3
Other techniques ................................................................................................................................. 51
1.1.3.1
1.1.3.1.1
1.1.3.2
1.2
2
Rotation ........................................................................................................................................... 51
Flumill AS ........................................................................................................................................ 51
Oscillation and transverse motion ................................................................................................... 52
1.1.3.2.1
Aqua Energy Solutions .................................................................................................................... 52
1.1.3.2.2
BioPower Systems .......................................................................................................................... 53
1.1.3.2.3
IHC Engineering Business Ltd. ....................................................................................................... 54
1.1.3.2.4
Pulse Tidal ...................................................................................................................................... 55
1.1.3.2.5
Robert Gordon University ................................................................................................................ 56
1.1.3.2.6
Tidal Sails AS .................................................................................................................................. 57
1.1.3.2.7
Vortex Hydro Energy ....................................................................................................................... 58
1.1.3.2.8
Other ............................................................................................................................................... 58
TIDAL BARRAGES ............................................................................................................................................ 59
KNOWN INITIATIVES IN NORTH WEST EUROPE ....................................................................................... 61
2.1
MARINET ..................................................................................................................................................... 61
2.2
SEA GENERATION ........................................................................................................................................... 62
2.3
PENTLAND FIRTH AND ORKNEY W ATERS MARINE ENERGY PARK ...................................................................... 64
2.4
THE NETHERLANDS ........................................................................................................................................ 66
2.5
FRANCE ......................................................................................................................................................... 67
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PRO-TIDE PROJECTS .................................................................................................................................... 68
3.1
PROVINCE OF ZEELAND................................................................................................................................... 68
3.2
PORT OF DOVER ............................................................................................................................................ 70
3.3
ISLE OF W IGHT............................................................................................................................................... 72
3.4
LABORATORY OF OCEANOLOGY AND GEOSCIENCES ......................................................................................... 74
3.5
W ATERWEGEN & ZEEKANAAL NV ..................................................................................................................... 76
4
EVALUATION FRAMEWORK ......................................................................................................................... 78
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REFERENCE LIST .......................................................................................................................................... 79
List of Tables
TABLE 4-1: EXAMPLE OF A MULTI CRITERIA ANALYSIS. ........................................................78
List of Figures
FIGURE 1-1: ILLUSTRATION OF ALSTOM'S TIDAL STREAM TURBINE (ALSTOM (2013)). ...................12
FIGURE 1-2: INSTALLATION OF THE HS300 (TAKEN FROM ANDRITZ, 2013). ..............................13
FIGURE 1-3: HS1000 (TAKEN FROM ANDRITZ, 2013). .......................................................13
FIGURE 1-4: CONCEPT DRAWING OF A FLOATING HYDRO-GEN TURBINE (TAKEN FROM AQUAPHILE,
2013). ............................................................................................................14
FIGURE 1-5: HYDRO-GEN TURBINE OUT OF THE WATER (TAKEN FROM AQUAPHILE, 2013). .............14
FIGURE 1-6: CONCEPT DRAWING OF THE FLOATING PADDLE WHEEL (TAKEN FROM AQUAPHILE, 2013).14
FIGURE 1-7: FLOATING PADDLE WHEEL (TAKEN FROM AQUAPHILE, 2013). .................................14
FIGURE 1-8: AR SERIES (TAKEN FROM ATLANTIS RESOURCES, 2013). .....................................16
FIGURE 1-9: AS SERIES (TAKEN FROM ATLANTIS RESOURCES, 2013)). ....................................16
FIGURE 1-10: AN SERIES (TAKEN FROM ATLANTIS RESOURCES, 2013). ...................................16
FIGURE 1-11: FLOATING MORILD II TIDAL POWER PLANT (TAKEN FROM HYDRA TIDAL (2013)). .......17
FIGURE 1-12: MORILD II TIDAL POWER PLANT ILLUSTRATION (TAKEN FROM HYDRA TIDAL (2013))...17
FIGURE 1-13: CORMAT PRINCIPLE (NAUTRICITY, 2013)). ...................................................18
FIGURE 1-14: FULL SCALE CORMAT (NAUTRICITY, 2013)....................................................18
FIGURE 1-15: EVOPOD MONO TIDAL TURBINE (TAKEN FROM OEL (2013)). ...............................19
FIGURE 1-16: EVOPOD TWIN TIDAL TURBINE (TAKEN FROM OEL (2013)). ...............................19
FIGURE 1-17: SABELLA D03 PROTOTYPE (TAKEN FROM SABELLA (2013)). ..............................20
FIGURE 1-18: SABELLA D10 (TAKEN FROM SABELLA (2013)). ............................................20
FIGURE 1-19: SR250 IN OPERATION MODE (TAKEN FROM SCOTRENEWABLES, 2013). ..................21
FIGURE 1-20: SR250 IN TRANSPORT/SURVIVABILITY MODE (TAKEN FROM SCOTRENEWABLES, 2013).21
FIGURE 1-21: TIDEL AT NAREC (TAKEN FROM NAREC (2013)). ...........................................23
FIGURE 1-22: TIDEL (TAKEN FROM SMD (2013)). ............................................................23
FIGURE 1-23: SWANSEA TURBINE (PROJECT CYGNET) (TAKEN FROM SWANTURBINES (2013)). .......24
FIGURE 1-24: DELTASTREAM (TAKEN FROM TEL (2013)). ...................................................25
FIGURE 1-25: TRITON TIDAL ENERGY PLATFORM, FLOATING (LEFT) AND OPERATING (RIGHT) (TAKEN
FROM TIDALSTREAM (2013)). ................................................................................26
FIGURE 1-26: TRITON TS WITH 25 STG50 TURBINES (TAKEN FROM TIDALSTREAM (2013)). .........27
FIGURE 1-27: SCHOTTEL STG50 (TAKEN FROM SCHOTTEL (2013)). ..................................27
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FIGURE 1-28: TOCADO T100 DESIGN (TAKEN FROM TOCARDO (2013)). ..................................28
FIGURE 1-29: TOCARDO T100 TEST SET-UP AT DEN OEVER (NL) (TAKEN FROM TOCARDO (2013)). .28
FIGURE 1-30: CONCEPT DRAWING OF THE FREE FLOW SYSTEM (TAKEN FROM VERDANT POWER, 2013).29
FIGURE 1-31: FREE FLOW SYSTEM TURBINES AT RITE PROJECT (SEPT 2008) (PHOTO: CHRISTOPHER
R. GRAY/VERDAN POWER, INC. TAKEN FROM VERDANT POWER, 2013). ..............................29
FIGURE 1-32: VHOCT 110 KW TURBINE (TAKEN FROM VOITH, 2013). ...................................30
FIGURE 1-33: VHOCT 1 MW TURBINE (TAKEN FROM VOITH, 2013). ......................................30
FIGURE 1-34: MODEL CC015A (TAKEN FROM CLEAN CURRENT, 2013). ...................................31
FIGURE 1-35: TURBINE FOR TIDAL APPLICATIONS (TAKEN FROM CLEAN CURRENT, 2013). ..............31
FIGURE 1-36: CONCEPT OF THE LUNAR TIDAL TURBINE (TAKEN FROM LUNAR ENERGY, 2013). ........32
FIGURE 1-37: REMOVAL OF TURBINE MODULE (TAKEN FROM OPEN HYDRO, 2013). ......................32
FIGURE 1-38: CONCEPT OF THE OPEN-CENTRE TURBINE (TAKEN FROM OPEN HYDRO, 2013). .........33
FIGURE 1-39: OPEN-CENTRE TURBINE AT EMEC (TAKEN FROM OPEN HYDRO, 2013). ..................33
FIGURE 1-40: CONCEPT DRAWING OF THE UEK (TAKEN FROM UEK, 2013). ..............................34
FIGURE 1-41: UNDERWATER ELECTRIC KITE (TAKEN FROM UEK, 2013). ..................................34
FIGURE 1-42: COMARENT (TAKEN FROM VAN BERKEL, 2013). ...............................................35
FIGURE 1-43: FULL SCALE TEST OF THE WAVE ROTOR (IHC, 2012). .......................................36
FIGURE 1-44: CURRENT DESIGN OF THE OCEAN MILL (IHC, 2012). ........................................36
FIGURE 1-45: BLUETEC WITH FOUR VERTICAL AXIS TURBINES (1 MW) (TAKEN FROM BLUEWATER,
2013). ............................................................................................................37
FIGURE 1-46: KOBOLD TURBINE (CALGANO & MOROSO, 2007). ............................................38
FIGURE 1-47: ENERMAR PROJECT (TETHYS, 2013). ............................................................38
FIGURE 1-48: VAHT TOP VIEW (TAKEN FROM BEC, 2013). ..................................................39
FIGURE 1-49: VAHT SIDE VIEW (TAKEN FROM BEC, 2013). ................................................39
FIGURE 1-50: CONCEPT OF THE ORYON WATERMILL (TAKEN FROM DEEPWATER-ENERGY, 2013). .....40
FIGURE 1-51:TEST SET-UP WITH THE ORYON WATERMILL (TAKEN FROM DEEPWATER-ENERGY, 2013).40
FIGURE 1-52: HYDROQUEST CONCEPT (TAKEN FROM HYDROQUEST, 2013). ..............................41
FIGURE 1-53: HYDROQUEST TURBINE FIXED TO A FLOATING BARGE (TAKEN FROM HYDROQUEST,
2013). ............................................................................................................41
FIGURE 1-54: DISMANTLED DAVIDSON-HILL TURBINE (TAKEN FROM TIDAL ENERGY, 2013). ..........42
FIGURE 1-55: ASSEMBLED DAVIDSON-HILL TURBINE (TAKEN FROM TIDAL ENERGY, 2013). ............42
FIGURE 1-56: DAVIDSON-HILL TURBINE MOUNTED ON THE SUPPORT STRUCTURE (TAKEN FROM TIDAL
ENERGY, 2013). .................................................................................................42
FIGURE 1-57: CONCEPT OF THE THAWT (TAKEN FROM KEPLER ENERGY, 2013). .........................43
FIGURE 1-58: SCALE MODEL (1:20) OF THE ROTOR (TAKEN FROM KEPLER ENERGY, 2013). ...........43
FIGURE 1-59: TURBINE GENERATOR UNIT (TAKEN FROM ORPC, 2013). ...................................44
FIGURE 1-60: RIVGEN® POWER SYSTEM (TAKEN FROM ORPC, 2013). ...................................44
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FIGURE 1-61: TIDGEN® POWER SYSTEM (TAKEN FROM ORPC, 2013). ...................................44
FIGURE 1-62: OCGEN® POWER SYSTEM (TAKEN FROM ORPC, 2013). ....................................44
FIGURE 1-63: EXAMPLE OF A 1:10 PROTOTYPE TEST (TAKEN FROM ATLANTISSTROM, 2013). ..........45
FIGURE 1-64: CONCEPT DRAWING OF THE ATLANTISSTROM TURBINE (TAKEN FROM ATLANTISSTROM,
2013). ............................................................................................................45
FIGURE 1-65: PROTOTYPE OF THE GR-40 WITH THE PROTRUDING BLADES (TAKEN FROM EHE, 2005).46
FIGURE 1-66: BLADE PITCH ADJUSTMENT ACCORDING TO THEIR RELATIVE POSITION IN THE ROTATION
CYCLE OF THE ROTOR (TAKEN FROM EHE, 2005). .........................................................46
FIGURE 1-67: FLOATING POWER STATION WITH SPOON-SHAPED BLADES (TAKEN FROM EHE, 2005). 46
FIGURE 1-68: HALES WATER TURBINE (TAKEN FROM HWT, 2013). ........................................47
FIGURE 1-69: VENTURI DUCTED HALES TURBINE. (TAKEN FROM HWT, 2013). ...........................47
FIGURE 1-70: PROTEUS CONCEPT (NEPTUNE RENEWABLE ENERGY, 2011). ................................48
FIGURE 1-71: FULL SCALE PROTOTYPE MOORED IN THE HUMBER. (PHOTOGRAPH: SEAN SPENCER/HULL
NEWS & PICTURES, 2013). ...................................................................................48
FIGURE 1-72: RUTTEN WATERWHEEL (TAKEN FROM KHAN, 2006). ..........................................49
FIGURE 1-73: EXIM TURBINE (TAKEN FROM WATER POWER & DAM CONSTRUCTION, 2003). ..........49
FIGURE 1-74: CONCEPT OF THE TIDENG ROTOR (TAKEN FROM TIDENG, 2013). ...........................50
FIGURE 1-75: TIDENG LAB TEST (TAKEN FROM TIDENG, 2013). .............................................50
FIGURE 1-76: CONCEPT OF THE FLUMILL SYSTEM (TAKEN FROM FLUMILL, 2013). ........................51
FIGURE 1-77: FLUMILL HELIX (TAKEN FROM FLUMILL, 2013). ................................................51
FIGURE 1-78: CONCEPT OF THE AES DESIGN (TAKEN FROM AES, 2013). .................................52
FIGURE 1-79: CONCEPT OF THE BIOSTREAM™ (TAKEN FROM BIOPOWER SYSTEMS, 2013). ..........53
FIGURE 1-80: STINGRAY MECHANICAL GENERAL ARRANGEMENT (TAKEN FROM EB, 2003). ..............54
FIGURE 1-81: PROTOTYPE OF THE STINGRAY (TAKEN FROM TETHYS, 2013). ..............................54
FIGURE 1-82: CONCEPT OF THE PULSE STREAM (TAKEN FROM PULSE TIDAL, 2013). ....................55
FIGURE 1-83: PS100 IN THE HUMBER RIVER (TAKEN FROM PULSE TIDAL, 2013). .......................55
FIGURE 1-84: SEA SNAIL (TAKEN FROM RGU, 2013). ........................................................56
FIGURE 1-85: CONCEPT OF THE TIDAL SAILS (TAKEN FROM TIDAL SAILS, 2013). ........................57
FIGURE 1-86 : WORKING PRINCIPLE OF THE VIVACE CONVERTER (TAKEN FROM VHE, 2013). ........58
FIGURE 1-87: CONCEPT OF AN ARRAY OF VIVACE CONVERTERS (TAKEN FROM VHE, 2013). ..........58
FIGURE 1-88: OPERATING PRINCIPLE OF A TIDAL BARRAGE (TAKEN FROM ESRU, 2002). ...............59
FIGURE 1-89: ROTOR DESIGN OPTIMIZATION TO IMPROVE FISH-FRIENDLINESS (PENTAIR FAIRBANKS
NIJHUIS, 2012). ................................................................................................60
FIGURE 1-90: AERATED SIPHON TURBINE.........................................................................60
FIGURE 2-1: OVERVIEW OF FACILITIES PARTICIPATING IN MARINET (TAKEN FROM MARINET, 2013).61
FIGURE 2-2: DRAWING OF THE SEAGEN S TURBINE (MCT, 2013). .........................................62
FIGURE 2-3: SEAGEN S WITH THE CROSS BEAM RAISED ABOVE THE WATER (MCT, 2013). .............63
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FIGURE 2-4: ARRAY AREA AND CABLE CORRIDOR OPTIONS FOR THE SKERRIES TIDAL STREAM ARRAY
(SEA GENERATION (WALES), 2013). .......................................................................63
FIGURE 2-5: PROJECT AREA FOR THE KYLE RHEA TIDAL STREAM ARRAY PROJECT
(ROYAL HASKONINGDHV, 2012). ...........................................................................64
FIGURE 2-6: OVERVIEW OF THE PENTLAND FIRTH AND ORKNEY WATERS MARINE ENERGY PARK:
ROUND 1 DEVELOPMENT SITES (HI-MARINE ENERGY PARK, 2012). ....................................65
FIGURE 2-7: SLUICE AT THE TIDAL TESTING CENTRE IN DEN OEVER (TAKEN FROM TTC, 2013). ......66
FIGURE 2-8: TOW TEST AT THE TIDAL TESTING CENTRE IN DEN OEVER (TAKEN FROM TTC, 2013). ..66
FIGURE 2-9: TIDAL POWER PLANT ON THE RANCE RIVER IN SAINT-MALO, FRANCE (TAKEN FROM
INFORSE, 2013). ..............................................................................................67
FIGURE 2-10: OPERATING PRINCIPLE OF THE TIDAL ENERGY PLANT IN THE RANCE (TAKEN FROM FRERS,
2005). ............................................................................................................67
FIGURE 3-1: LOCATION OF LAKE GREVELINGEN IN THE NETHERLANDS. .....................................68
FIGURE 3-2: BROUWERSDAM SEPARATING LAKE GREVELINGEN FROM THE NORTH SEA. ..................68
FIGURE 3-3: CONCEPT OF A BULB TURBINE AS POSSIBLE TURBINE FOR THE BROUWERSDAM. ............69
FIGURE 3-4: CONCEPT OF A SIPHON TURBINE AS POSSIBLE TURBINE FOR THE BROUWERSDAM. .........69
FIGURE 3-5 : TIDAL ENERGY INVESTIGATION ZONE OF THE PORT OF DOVER. ...............................70
FIGURE 3-6: LOCATION OF THE SOEC NURSERY AND DEVELOPMENT SITES. ...............................73
FIGURE 3-7: BATHYMETRY OF THE SOEC NURSERY SITE. ......................................................73
FIGURE 3-8: INDICATIVE BERTH LAYOUT AT THE SOEC DEVELOPMENT SITE. ...............................73
FIGURE 3-9: EXPERIMENTAL STATION DEVELOPED BY LOG. ...................................................74
FIGURE 3-10: EXAMPLE OF MEASUREMENTS PERFORMED WITH THE TRIPOD. DEPLOYMENT WEST OF THE
BOULOGNE HARBOUR. TOP: VELOCITY MEASUREMENTS; MIDDLE: REYNOLDS STRESS (SOUTH-NORTH
COMPONENT); BOTTOM: TURBULENT KINETIC ENERGY PRODUCTION RATE. .............................75
FIGURE 3-11: TOWED CURRENT PROFILER. .......................................................................75
FIGURE 3-12: SURFACE CURRENTS ON FLOOD (HW-0.5 H) IN BOULOGNE HARBOUR. ....................75
FIGURE 3-13: LATERAL VIEW OF THE CONCEPTUAL DESIGN OF THE HYDROPOWER PLANT AT THE LOCK IN
HEUSDEN. .........................................................................................................76
FIGURE 3-14: SELECTION OF A SUITABLE LOCATION FOR PERFORMING SMALL-SCALE TIDAL CURRENT
TURBINE TESTS USING AN ENERGY DENSITY MAP BASED ON A 2D-HYDRODYNAMIC MODEL. .........77
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0
INTRODUCTION
0.1 PRO-TIDE
Waterwegen en Zeekanaal nv (W&Z) is participating in the European project PRO-TIDE,
funded by the Interreg IVB North-West Europe program. The main goal of this project is
“to increase the use of renewable energy by promoting innovative, sustainable and cost
effective solutions for tidal energy through research, development, testing and
comparison of different forms of tidal energy at different locations and circumstances, in
coastal zones and estuaries”.
0.2 AIM OF THE STUDY
This study tries to give an overview of both available and emerging techniques for
harvesting tidal energy. For this, the study heavily relies – but not solely – on the
techniques and technologies presented during the Master Class on Innovative Tidal Energy
Techniques, hosted by W&Z, in the buildings of Flanders Hydraulics Research in Antwerp,
Belgium, on Thursday May 30, 2013.
The focus will be on tidal current energy convertors and tidal barrages, since these are
the two methods considered in the partner projects.
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0.3 STRUCTURE OF THE REPORT
The report starts with a concise overview of the different methods for converting tidal
energy into electricity (Chapter 1). For each type of energy conversion method, the
convertors currently available or under development, are listed and shortly described.
After that, Chapter 2 discusses the known project initiatives in North West Europe
regarding tidal energy. Next, an overview of the projects as performed by the PRO-TIDE
partners is given in Chapter 3. The report ends with the definition of the evaluation
framework, that can be used to compare different techniques.
0.4 DISCLAIMER
In making this overview, special care was taken to be as exhaustive as possible. However, new
tidal energy conversion techniques are being developed constantly throughout the globe, which
makes a watertight overview difficult, if not impossible. Moreover, existing technologies are
continuously being improved, and the market for developing tidal energy convertors shows to be
highly dynamic, i.e. it is characterized by an almost constantly changing composition of developers
and manufacturers. Inevitably, some technologies or companies might not be listed in this report.
Also, very recent information regarding a technology or a company’s position in the market (e.g.
name change, take-over, liquidation etc.) although available at the time of writing, might not have
made this report. Therefore, readers wanting more information regarding a certain technology
should always contact the manufacturer directly. Nor PRO-TIDE or any of the PRO-TIDE partners
can be held liable for any errors or matters of incompleteness.
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1
TIDAL ENERGY TECHNIQUES
In this chapter, first the different energy conversion methods to harvest tidal energy will
shortly be discussed. The aim is to give an overview of the main principles rather than
explaining in detail the technical aspects. Then, a list of technologies is given in
alphabetical order (by company name). When a company develops multiple techniques, it
is classified according to their leading technology, as interpreted by the authors. However,
for sake of completeness, reference to the relevant paragraph will be made in the
appropriate technology section as well.
1.1 TIDAL CURRENT ENERGY CONVERTORS
Tidal current energy convertors extract energy from the water flow, by either using the lift
forces or the drag forces – originating from the water flow interacting with the convertor –
to generate a mechanical motion, i.e. rotation, translation, vibration, of a movable part of
the convertor, which in turn is connected to a electric generator.
The lift forces originate from pressure gradients due to differences in flow velocity around
hydrodynamically shaped blades. The same principle is applied in airplanes: the wings
have a hydrodynamically favourable shape, resulting in a flow pattern that causes a
pressure gradient over the wing. The plane is lifted vertically, although the wind flow is
horizontal. Drag forces are the result of the water ‘pushing’ directly against a surface,
which sets the surface in motion. The reverse principle was applied to the steamboats
sailing the Mississippi in the 19th century. Generally, turbines relying on lift forces have
higher conversion efficiencies compared to those relying on drag forces. The latter on the
other hand are more easily to design and construct.
Two main types of rotor turbines can be discerned: horizontal axis and vertical axis
marine current energy convertors. While the latter are omnidirectional by concept, which
is undoubtedly an advantage, part of the blade rotor will always move opposite the flow
direction, which of course forms an additional resistance. Hence much attention must be
given to rotor design.
Next to the above described technologies, tidal current energy convertors based on
oscillation exist as well. These convertors are fitted with e.g. hydrofoils that start
oscillating due to the current flowing around it. The oscillating motion then can be used to
generate electricity.
Because of their operating principle, the application of tidal current energy convertors is
not limited to offshore applications. When properly scaled these convertors can be
deployed in rivers as well. Nevertheless, the term ‘marine current turbine’ is kept
throughout the text.
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1.1.1 HORIZONTAL AXIS MARINE CURRENT TURBINES USING LIFT FORCES
Horizontal axis marine current turbines (HAMCTs) using lift forces have an axis parallel to
the direction of flow, and so could be described as ‘underwater windmills’. Additionally a
duct channel can be incorporated into the design, causing an increase of the water
velocity and hence an increase in energy density.
1.1.1.1 Open HAMCTs
1.1.1.1.1
Alstom (previously Tidal Generation Ltd)
Alstom, having teams in both France and the UK working on tidal and wave energy,
acquired Tidal Generation Ltd (TGL), and with it its technology for tidal stream turbines.
The system exists from a bottom mounted, three-bladed turbine. It is provided with a
yawing nacelle, so the turbine is aligned along the direction of flow at all times. The
500 kW turbine has a blade diameter of 18 m, a cut-in velocity1 of 1 m/s, a rated velocity2
of 2.7 m/s, and a maximum operating water velocity of 5 m/s (Alstom, 2013).
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Figure 1-1: Illustration of Alstom's tidal stream turbine (Alstom (2013)).
The company recently finished testing with their 500 kW turbine for 2 years at the
European Marine Energy Centre (EMEC) in Scotland. The EMEC is part of the Pentland
Firth and Orkney Waters Marine Energy Park, on which is elaborated further in §2.3.
The following website contains more information:
http://www.alstom.com/power/renewables/ocean-energy/tidal-energy.
1
The minimal velocity required for the rotor to start spinning.
2
The velocity at which the turbine generates the design level of power.
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1.1.1.1.2
Andritz Hydro Hammerfest
ANDRITZ HYDRO Hammerfest is a Norwegian-based company, and developed and
installed the HS300, a 300 kW prototype in Kvalsund, Norway. The turbine is deployed at
50 m depth. They also installed a 1 MW pre-commercial turbine at EMEC (§2.3), the
HS1000. With the HS1000, the company is planning to develop a tidal turbine array at
their Islay and Duncansby Head sites in Scotland.
The turbines consist of a three-bladed rotor, and bidirectionality is obtained by pitching
the blades. The support structure is designed as a tripod, which minimizes the footprint
on the seabed; the structure’s foundation is gravity based.
13
Figure 1-2: Installation of the HS300 (taken from
Andritz, 2013).
More information can be found on the company’s website:
http://www.hammerfeststrom.com.
Figure 1-3: HS1000 (taken
from Andritz, 2013).
IMDC nv
1.1.1.1.3
Aquaphile sarl
Aquaphile sarl, a French company, develops a floating turbine for sea, estuaries, rivers or
streams. According to Aquaphile (2013), their Hydro-Gen turbines have a cut-in speed of
0.3 m/s and a cut-out speed of 3.5 m/s. The propeller consists of two or three blades,
ranging from 3 m to 5 m. “The turbines are designed following the possibilities and
requirements from 10 kW to 100 kW” (Aquaphile, 2013).
Figure 1-4: Concept drawing of a floating
Hydro-Gen turbine (taken from Aquaphile,
2013).
Figure 1-5: Hydro-Gen turbine out of the
water (taken from Aquaphile, 2013).
Currently the company developments focus on the above mentioned HAMCTs – and that is
why it is listed here –, but they offer ‘taylor made’ paddle wheel current turbines,
applicable in situations with very low depth or very turbulent flow (Aquaphile, 2013).
Figure 1-6: Concept drawing of the floating
paddle wheel (taken from Aquaphile, 2013).
Figure 1-7: Floating paddle wheel (taken
from Aquaphile, 2013).
More information can be found on the following website: http://www.hydro-gen.fr.
14
IMDC nv
1.1.1.1.4
AquaScrew bvba
Aquascrew bvba is a Flemish company developing a progressive screw, which should
make it very fish friendly. Developments are leaving lab testing phase, and efforts are
being made to establish the first field tests. The system can be installed in rivers with
sufficient current and depth, but the technology can also be applied in tidal streams or
ocean currents.
Further information is available under a non-disclosure agreement only.
15
IMDC nv
1.1.1.1.5
Atlantis Resources Corporation
The English Atlantis Resources Corporation develops and manufactures tidal energy
covertors. The AR series (Figure 1-8) are commercial scale horizontal axis turbines with
fixed pitch blades. Bidirectionality is provided by yawing the turbine each tidal exchange.
The AR-1000 is rated at 1 MW at 2.65 m/s water flow velocity. In the summer of 2011,
the AR-1000 was successfully deployed and commissioned at the EMEC (§2.3) (Atlantis
Resources, 2013).
Figure 1-8: AR series (taken from Atlantis Resources, 2013).
The company also develops a ducted horizontal axis turbine, the AS series, suitable for
river environments and tidal locations (Figure 1-9). “The AS turbines are rated at 2.6 m/s
and are available in 100 kW, 500 kW and 1 MW configurations.” (Atlantis Resources,
2013). Finally, the AN series are shallow water turbines, using “Aquafoils™ to capture
momentum from the flow of water to drive a chain perpendicular to the flow.” (Atlantis
Resources, 2013). An example is shown in Figure 1-10.
Figure 1-9: AS series (taken from Atlantis
Resources, 2013)).
Figure 1-10: AN series (taken from Atlantis
Resources, 2013).
More information can be found on the following website:
http://www.atlantisresourcescorporation.com.
16
IMDC nv
1.1.1.1.6
Hydra Tidal
The Norwegian company Hydra Tidal, a subsidiary of STRAUM, developed and installed the
prototype Morild II tidal power plant, in the Gimsoy stream in Lofoten, Norway. The plant
is a floating system and can be towed to the deployment location (Figure 1-11). It has a
dual configuration: four rotors are foreseen, in a pair wise opposite configuration (Figure
1-12). Opposite rotors turn in opposite direction, thus limiting the torque load on the
floating structure. A blade pitch of 180° is possible. Remarkable is the fact that the rotor
blades are from wood.
17
Figure 1-11: Floating Morild II tidal power
plant (taken from Hydra Tidal (2013)).
Figure 1-12: Morild II tidal power plant
illustration (taken from Hydra Tidal (2013)).
The rotor diameters measures 23 m, and the plant has an installed capacity of 1.5 MW.
On-site maintenance access is possible through the vertical shaft.
More information on this
http://www.hydratidal.info.
technology
and
the
company
can
be
found
on:
IMDC nv
1.1.1.1.7
Nautricity Ltd
The Scottish Nautricity Ltd develops the CoRMaT device. It is a contra-rotating turbine,
i.e. it employs two closely spaced contra-rotating rotors, driving a contra-rotating
electrical generator. The first rotor has three blades rotating in a clockwise direction while
the second rotor, located directly behind the first, has four blades rotating in an anticlockwise direction (Figure 1-13).
Figure 1-13: CoRMaT principle
(Nautricity, 2013)).
Figure 1-14: Full scale CoRMaT
(Nautricity, 2013).
Due to the contra-rotating rotors, reactive torque is eliminated thus removing the need
for fixed foundations. The device has buoyancy chambers at the front and rear sections of
the nacelle for subsurface floating. Water depths from 8 m to 500 m are possible.
Recently, the company installed a full scale CoRMaT device (Figure 1-14) at EMEC,
situated in the Pentland Firth and Orkney Waters Marine Energy Park (§2.3).
Because the device comprises only a small number of simple sub-assemblies, it is
relatively easily maintained. More information can be found on:
http://www.nautricity.com.
18
IMDC nv
1.1.1.1.8
Oceanflow Energy Ltd
The English company Oceanflow Energy Ltd developed a semi-submerged floating energy
capture device, the Evopod™. Several different configurations are envisaged, varying
from a single turbine (Figure 1-15) over a double turbine (Figure 1-16) to a multi-turbine
platform.
Figure 1-15: Evopod Mono Tidal Turbine
(taken from OEL (2013)).
Figure 1-16: Evopod Twin Tidal Turbine (taken
from OEL (2013)).
After a 1/10th scale test in Strangford Narrows (Northern Ireland, UK), Oceanflow is
currently developing a 1/4th scale mono tidal turbine Evopod™. This scale model has a
nominal generation capacity of 35 kW, at flow velocities of 4 knots, or about 2 m/s. The
scale model has a rotor diameter of 4.5 m, and will be installed in the Sanda Sound,
South Kintyre (Scotland, UK).
More information on the technology and the company can be found on their website:
http://www.oceanflowenergy.com.
19
IMDC nv
1.1.1.1.9
SABELLA SAS
SABELLA SAS installed the first French submarine tidal stream turbine, Sabella D03, in
2008 (Figure 1-17). This first experimental prototype has a diameter of 3 m, and was
successfully tested for a year in Bénodet (Brittany, France). The company currently
develops turbines in the range D10, D12 and D15 (rotor diameter 10, 12 or 15 m),
designed for speeds from 2.5 m/s to 4.0 m/s, producing 0.3 to 2.5 MW. The multibladed
rotors can operate bidirectionally. The turbine unit can be disconnected from the support
frame for maintenance.
20
Figure 1-17: Sabella D03 prototype
(taken from SABELLA (2013)).
Figure 1-18: Sabella D10 (taken from
SABELLA (2013)).
The website of the company: http://www.sabella.fr.
IMDC nv
1.1.1.1.10 Scotrenewables Tidal Power Ltd
The Scottish company Scotrenewables Tidal Power Ltd develops the Scotrenewables Tidal
Turbine (SRTT), a floating structure with dual horizontal axis rotors. The two rotors can be
retracted during transport or during heavy weather conditions at sea. After a series of
scale model tests, the 250 kW prototype, the SR250, was installed at EMEC (§2.3) in
March 2011. The SR250 comprises a 33 m long steel tube with a diameter of 2.3 m
(Scotrenewables, 2013). The counter-rotating rotors each have a diameter of 8 m. The
rotors have a fixed pitch, but omnidirectional operation is achieved through the patented
mooring system. Most of the electromechanical equipment are located in the main hull
tube.
Figure 1-19: SR250 in operation mode
(taken from Scotrenewables, 2013).
Figure 1-20: SR250 in transport/survivability
mode (taken from Scotrenewables, 2013).
Currently the company is designing the SR2000, capable of delivering 2 MW at 3 m/s flow
velocity, which will undergo a 12 month testing programme at EMEC.
The company’s website gives more information on the technology, the tests and the
future plans: http://www.scotrenewables.com.
21
IMDC nv
1.1.1.1.11 Siemens (previously Marine Current Turbines Ltd)
Marine Current Turbines Ltd (MCT) pioneered by designing, building and installing the
world’s first commercial tidal stream power station, SeaGen, in Strangford Lough,
Northern Ireland, UK. MCT is now wholly owned by Siemens. More information on this UK
based company and the SeaGen project can be found in §2.1.
The SeaGen power station consists of a double two-bladed turbine group, that is
retractable from the water, along the support pylon (Figure 2-3). This enables relatively
easy maintenance.
The company website is: http://www.marineturbines.com.
22
IMDC nv
1.1.1.1.12 SMD
The British company SMD designed and tested a 1/10th scale model, known as TidEL, at
the National Renewable Energy Centre (NaREC) in Blyth, UK (Figure 1-21, Figure 1-22).
The TidEL system consists of two contra-rotating rotors mounted together by a cross
beam. The system is buoyant.
Figure 1-21: TidEL at NaREC (taken
from NaREC (2013)).
Figure 1-22: TidEL (taken from SMD (2013)).
A full scale prototype is being developed, and will consist of two 500 kW turbines. The
mooring system will allow the turbines to align themselves along the tidal flow
automatically. Such 1 MW dual units are designed for an offshore tidal environment,
having peak velocities up to 9 knots (about 4.5 m/s) or more, in water depths of greater
than 30 m.
More information
development.htm.
is
given
on:
http://www.smd.co.uk/products/renewables/design-
23
IMDC nv
1.1.1.1.13 Swanturbines
Swanturbines, a company in Wales (UK), is developing a 330 kW demonstrator
(Swanturbines, 2013). Their system uses a gravity based foundation, and a hinged pylon
enables the turbines to orientate themselves along the current (Figure 1-23). They are
currently working on a commercial installation methodology (together with Jumbo
Offshore).
Most recently Swanturbines has extended its focus towards smaller inshore turbines,
capable to operate in estuaries and near shore sites. Tests with the ½ scale tests of the
turbine blade and installation system of the Cygnus ISTT (In-Shore Tidal Turbine) were
performed.
24
Figure 1-23: Swansea Turbine (project Cygnet) (taken from Swanturbines (2013)).
The company website can be visited at: http://www.swanturbines.co.uk.
IMDC nv
1.1.1.1.14 Tidal Energy Ltd (originally Tidal Hydraulic Generators Ltd)
Tidal Energy Ltd – previously Tidal Hydraulic Generators Ltd – is based in Wales (UK), and
develops the DeltaStream technology (TEL, 2013). Basically, DeltaStream consists of a
free-standing triangular structure with three turbines, which requires no drilling or piling
into the seabed to be deployed in a stable manner, due to the patented “Rock foot”. A
patented predictive control system creates active damping effects so the frame withstands
and absorbs dynamic forces resulting from turbulence. The rotor blades’ orientation
towards the flow can be adjusted to vary the swept area in function of the hydraulic
conditions (patent filed in January 2013).
25
Figure 1-24: DeltaStream (taken from TEL (2013)).
More information can be found on the company’s website: http://www.tidalenergyltd.com.
IMDC nv
1.1.1.1.15 TidalStream Ltd – SCHOTTEL GmbH
TidalStream Ltd is based in the UK and develops the Triton tidal energy platform
(TidalStream, 2013). It is a floating structure, capable of supporting up to 10 MW of
turbine capacity from a single seabed installation. The platform can be fitted with turbines
before sailing it to the site. It is then put into operation by water ballasting (Figure 1-25).
While in operating position, access to the electromechanical equipment is possible via the
top of the vertical buoys.
26
Figure 1-25: Triton tidal energy platform, floating (left) and operating (right) (taken from
TidalStream (2013)).
It should be noted that the company itself does not produce turbines; the Triton system is
a support system for third-party turbine developers. It is highly adaptable: it can
accommodate several rows of smaller turbines, or fewer turbines with larger rotor
diameter. The Germany based company SCHOTTEL GmbH plans to use the Triton system
(Figure 1-26).
SCHOTTEL GmbH develops the SCHOTTEL Tidal Generator (STG) (SCHOTTEL, 2013). The
STG50, shown in Figure 1-27, has a rotor diameter of 4.0 to 4.5 m, is designed for rated
flow speeds of approximately 2.5 m/s – with a maximum of 5.0 m/s, and generates a
rated power of 45 to 50 kW (grid ready). The turbine is light weight (800 kg), and the
company claims that in total only 16 tons of material are required to obtain a capacity of
1 MW, compared to 130 ton for existing single 1 MW turbines. Both riverine and off-shore
applications are possible.
IMDC nv
Figure 1-26: Triton TS with 25 STG50
turbines (taken from TidalStream (2013)).
Figure 1-27: SCHOTTEL STG50 (taken from
SCHOTTEL (2013)).
The website of TidalStream Ltd is: http://www.tidalstream.co.uk.
The website of SCHOTTEL GmbH is: http://www.schottel.de/schottel-group/schottelworldwide/josef-becker-forschungszentrum/schottel-tidal-and-current-energy.
27
IMDC nv
1.1.1.1.16 Tocardo International BV
Tocardo International BV is a Dutch based company, producing tidal current turbines since
2008. The concept was developed by Teamwork Technology, an incubator for renewable
concepts such as energy, transport and housing. Since 2012 the company is fully
commercial when selling the first turbines to clients in Nepal and Japan (Tocardo, 2013).
Tocardo offers turbines in the range of 100-1000 kW, with the smaller turbines being
suitable for river currents or inshore tidal currents, and the larger turbines being specially
designed for offshore tidal currents. Figure 1-28 shows the design principle of the smallest
turbine (100 kW) in their range, the T100, suitable for riverine applications. Larger
turbines are T200, T500 and T1000. Each type of turbine can be fitted with a different
rotor size, depending on the project site. The turbines can be bottom mounted, installed
underneath floating platforms or retrofitted to existing structures like bridges and
barrages (Figure 1-29).
Instead of focusing on efficiency the company decided to focus on reliability and
affordability, resulting in a simple design with only minimal maintenance requirements.
The patented rotor blades reverse automatically when the current changes direction, so
bi-directional operational becomes possible without the need for the nacelle to rotate
around a vertical axis.
The company has a turbine “installed in Den Oever, The Netherlands, [that] has been
operational for 5 years and is delivering electricity to Dutch households” (Tocardo, 2013).
Figure 1-28: Tocado T100
design (taken from Tocardo
(2013)).
Figure 1-29: Tocardo T100 test set-up at Den Oever (NL)
(taken from Tocardo (2013)).
More information regarding the Tocardo turbines can be found on:
http://www.tocardo.com.
28
IMDC nv
1.1.1.1.17 Verdant Power Inc.
Verdan Power Inc. is a USA-based company developing the Free Flow Kinetic Hydropower
System, three-bladed horizontal axis turbines. The Free Flow System is bottom mounted.
The rotor is fixed at the tail of the nacelle instead of the nose. A yawing system enables
fully bidirectional operation.
The company’s Generation 4 System was successfully demonstrated from 2006-2009 in
the RITE project (Roosevelt Island Tidal Energy) in New York City’s East River. The project
comprised of six full-scale tidal turbines, “representing the world’s first operation of a
grid-connected tidal turbine array” (Verdant Power, 2013). The company is planning to
develop a 1 MW pilot comprised of up to 30 Generation 5 turbines.
29
Figure 1-30: Concept drawing
of the Free Flow System (taken
from Verdant Power, 2013).
Figure 1-31: Free Flow System Turbines at RITE Project
(Sept 2008) (Photo: Christopher R. Gray/Verdan Power,
Inc. Taken from Verdant Power, 2013).
More information can be found on: http://verdantpower.com.
IMDC nv
1.1.1.1.18 Voith
The German Voith Hydro Ocean Current Technologies (VHOCT) – a Voith and Siemens
Company – is a Center of Competence for the development of ocean current power
stations (VHOCT, 2013). Voith developed and deployed a 110 kW test turbine (Figure
1-32) near the South Korean Island of Jindo. It is a 1/3th scale model. The turbine has a
rotor diameter of 5.3 m, and reaches it rated capacity at a current speed of 2.9 m/s. The
rotor blades are designed in such a way that the system works bidirectionally without
yawing.
30
Figure 1-32: VHOCT 110 kW turbine (taken
from Voith, 2013).
Figure 1-33: VHOCT 1 MW turbine (taken
from Voith, 2013).
The next step is to install a full-size turbine, with a rotor diameter of 16 m and a rated
capacity of 1 MW at 2.9 m/s (Figure 1-33), at the European Marine Energy Center (EMEC)
in Scotland. This system will be mounted on a drilled monopole, unlike the gravity based
foundation of the 110 kW model in Jindo.
The company stresses the simplicity and sturdiness of their system, in order to obtain low
maintenance requirements. More information can be found on:
http://www.voith.com/en/products-services/hydro-power/ocean-energies/tidal-currentpower-stations--591.html.
IMDC nv
1.1.1.2 Ducted HAMCTs
Horizontal axis marine current turbines can be ducted, i.e. provided with a ventureshaped channel, the aim being to accelerate the water passing the turbine. Moreover, the
duct results in a flow pattern that is more perpendicular to the rotor, in case when the
current is not. Of course, a duct comes with a higher material cost.
1.1.1.2.1
Clean Current Power Systems Inc.
Clean Current Power Systems Inc. is a Canadian company, developing turbines for both
riverine and tidal applications. The river turbines family covers a range of diameters from
1.5 m (CC015A) to 3.5 m (CC035A), with a rated power output of 12-65 kW at 3 m/s. The
turbines can be deployed in a water depths of minimum 3 m for the CC015A to a
minimum of 5.5 m for the CC035A (Clean Current, 2013).
31
Figure 1-34: Model CC015A (taken
from Clean Current, 2013).
Figure 1-35: Turbine for tidal applications (taken
from Clean Current, 2013).
For tidal applications, a yawing mechanism is provided, to align the turbine along the flow
(Figure 1-35). The family of tidal in-stream turbines has larger dimensions, starting from
3.5 m diameter (CC035A) to 10.0 m diameter (CC100A). Consequently the rated power
output at 3 m/s is larger, ranging from 65 kW to 500 kW. The minimal water depths
range from 5.5 m (CC035A, same as above) to 13.0 m (CC100A) (Clean Current, 2013).
The company’s website gives more details on the technical specifications:
http://www.cleancurrent.com.
IMDC nv
1.1.1.2.2
Lunar Energy
The Scottish company Lunar Energy develops the Lunar Tidal Turbine (LTT) (Figure 1-36).
The load bearing self-supporting foundations requires no expensive seabed preparations,
and hence “allows for a rapid installation process” (Lunar Energy, 2013). The turbine can
be lifted from the duct, e.g. for maintenance purposes (Figure 1-37).
Figure 1-36: Concept of the Lunar Tidal
Turbine (taken from Lunar Energy, 2013).
Figure 1-37: Removal of turbine module
(taken from Open Hydro, 2013).
Due to the venturi duct, no yawing mechanism is required, because the flow is
straightened as it approaches the blades. Also the duct “removes the need for blade pitch
control” (Lunar Energy, 2013).
More information is given on the company’s website: http://www.lunarenergy.co.uk.
32
IMDC nv
1.1.1.2.3
Open Hydro
The Irish Open Hydro, a DCNS company, develops the Open-Centre Turbine, a ducted
horizontal axis turbine, of which the blades of the rotor are not connected to a central
nacelle, but to the outer rim (Figure 1-38). According to Open Hydro (2013), the “open
centre increases efficiency [and provides] an exit route for marine life.” The generator is
integrated in the outer rim of the device.
The company installed a 6 m diameter test unit at EMEC (§2.3), which “produces enough
energy to supply 150 average European homes and save the emission of over 450 tonnes
of CO2 greenhouse gas each year.” (Open Hydro, 2013). The test turbine is suspended
between a twin-piled structure (Figure 1-39), enabling testing of “future generations of
the Open-Centre Turbine at minimal cost” (Open Hydro, 2013), but all commercial
deployments will be mounted on the seabed, as shown in Figure 1-38.
33
Figure 1-38: Concept of the Open-Centre
Turbine (taken from Open Hydro, 2013).
The
company’s
website
http://www.openhydro.com.
gives
Figure 1-39: Open-Centre Turbine at EMEC
(taken from Open Hydro, 2013).
more
information
on
this
technology:
IMDC nv
1.1.1.2.4
UEK Corporation
The USA-based company UEK Corporation is designing and developing the Underwater
Electric Kite (UEK) Dual Hydroturbine System. The standard design “accommodates
velocities from 4 knots up to 8 knots” (UEK, 2013), i.e. approx. 2-4 m/s. For the standard
model, at 2.5 m/s the name plate capacity is 90 kWe, since two 45 kWe generators are
installed. The dimensions are approximately 3 m x 5.5 m x 4.6 m at approximately
2.6 tons. The runner diameter is 8 ft, or 244 cm (UEK, 2013). According to UEK (2013),
“fish, seabirds and mammals are protected from entering the turbine intakes by screens
and efficient bubbler deterents.”
Figure 1-40: Concept drawing of the
UEK (taken from UEK, 2013).
The following website
http://uekus.com.
gives
Figure 1-41: Underwater Electric Kite (taken from
UEK, 2013).
more
details
on
the
Underwater
Electric
Kite:
34
IMDC nv
1.1.2 CROSS AXIS MARINE CURRENT TURBINES
Cross axis marine current turbines can have their axis either horizontally or vertically
positioned. In both cases the water flow is perpendicular to the axis. As with the
horizontal axis turbines, devices can be open or ducted.
1.1.2.1 Open VAMCTs
Open vertical axis marine current turbines have the main advantage that they require no
yawing mechanism to operate omnidirectionaly. Moreover, the vertical axis enables that
the electromechanical equipment can be easily installed above the waterline, which
enables an easier access for maintenance (van Berkel, 2013).
1.1.2.1.1
Aquascientific
Aquascientific is an English research and development company in the field of ocean and
tidal energy extraction (Aquascientifc, 2013). They develop a turbine that utilises both lift
and drag in an optimal combination, which is, according to Aquascientific (2013), “more
efficient than propeller type designs”, and is “key to achieving high conversion efficiency
particularly at low flow velocities of less than 2 m/s”.
Wind tunnel trials confirmed the predicted power extraction efficiency, and water flow
trials are underway (Aquascientific, 2013). The turbine will be positioned by anchoring
and cabling, and will be “resilient to changes in flow velocity and direction“
(Aquascientific, 2013).
The
above
information
was
http://aquascientific2.moonfruit.com.
taken
from
the
company’s
website:
Further information is available under a non-disclosure agreement only.
1.1.2.1.2
Comarent
The Comarent turbine is a vertical axis turbine, the rotor of which exists from hydrofoils
instead of blades (Figure 1-42). The turbine is moored to the bed. Except from the picture
in Figure 1-42, which is taken from van Berkel (2013), no additional information could be
found on this technology.
Figure 1-42: Comarent (taken from van Berkel, 2013).
35
IMDC nv
1.1.2.1.3
Edinburgh Designs Ltd
In van Berkel (2013), a vertical axis turbine is depicted from Edinburgh Designs Ltd. This
Scottish company has been specialising in the design, manufacture and installation of a
wide range of wave and tidal generators, i.e. devices that generate waves and water level
changes. Those generators can be used for instance in research labs or for recreational
purposes.
At the moment of writing this report, no information regarding possible turbine
development could be found.
1.1.2.1.4
IHC Merwede – Bluewater
The Dutch company IHC Merwede acquired the Wave Rotor technology (Figure 1-43) from
Ecofys, another Dutch company, in 2012. Since then, IHC Merwede further develops and
commercializes the concept (Figure 1-44).
36
Figure 1-43: Full scale test of the Wave
Rotor (IHC, 2012).
Figure 1-44: Current design of the
Ocean Mill (IHC, 2012).
The turbine can be fitted to existing infrastructure, e.g. bridges or windmill support
structures, or on a floating pontoon. For this last application, a possible solution is via
Bluewater’s Tidal Energy Converter (BlueTEC) open-architecture floating support platform,
as shown in Figure 1-45. The figure shows an application with vertical axis turbines, but a
solution with horizontal axis turbines is possible as well.
IMDC nv
Figure 1-45: BlueTEC with four vertical axis turbines (1 MW) (taken from Bluewater,
2013).
Currently, IHC Merwede is investigating the possibilities to increase the turbine’s
efficiency by using active pitch of the blades. The active pitch re-orientates the blades
during rotation, so as to minimize resistance when the blade is turned towards the flow
direction.
More information on the Ocean Mill can be found on: http://www.ihctidalenergy.com.
The website of the Dutch based company Bluewater is: http://www.bluewater.com.
37
IMDC nv
1.1.2.1.5
INSEAN and Ponte di Archimedi S.p.A.
The Italian National Institute for Naval Architecture Studies and Testing (INSEAN) and
Ponte di Archimedi developed the Kobold turbine (Calgano & Moroso, 2007). Figure 1-46
shows a computer image of the turbine. A test project, the Enermar project (Tethys,
2012) was launched in 2011, in which the turbine was installed in the Strait of Messina,
along the Sicilian coast (Figure 1-47).
Figure 1-46: Kobold turbine (Calgano &
Moroso, 2007).
Figure 1-47: Enermar project (Tethys,
2013).
38
IMDC nv
1.1.2.2 Ducted VAMCTs
As with the HACMTs, VAMCTs can be provided with a duct channel, that aims at increasing
the flow velocity and thus the power output of the turbine.
1.1.2.2.1
Blue Energy Canada Inc.
Blue Energy Canada Inc. is based in Richmond, British Columbia (Canada). The company
develops the so-called vertical axis hydro turbine (VAHT), that is fitted with four vertical
hydrofoil blades (Figure 1-48). The blades employ a hydrodynamic lift principle that
causes the turbine foils to move proportionately faster than the speed of the surrounding
water. The rotation speed is in the range of 5-30 rpm, which is fairly low, so a significant
influence on the movement of aquatic fauna is not expected.
39
Figure 1-48: VAHT top view (taken from BEC,
2013).
Figure 1-49: VAHT Side view (taken from
BEC, 2013).
The rotor “is mounted in a marine caisson which direct the water flow through the turbine,
houses the rotor and supports the generator and electronic controls in a dry climate
controlled machinery room above the water line” (BEC, 2013).
The patented modular approach makes the system highly suitable to construct complete
tidal bridges, in which the modules are stacked. On the other side of the power spectrum,
floating micro turbines delivering 1-2 kW are possible as well.
The company’s website gives more information: http://www.bluenergy.com.
IMDC nv
1.1.2.2.2
Deepwater Energy BV
Deepwater-Energy BV, a Dutch company, is commercializing the Oryon Watermill, a
concept developed by Oryon Consultancy & Development, also a Dutch company. The
Oryon Watermill can be installed in rivers, tidal currents, ocean currents or artificially
created currents (e.g. at weirs or locks) of 1 m/s and higher. Because of the low rotation
rate there should be no negative effects on underwater fauna and flora (DeepwaterEnergy, 2013).
The turbine can consist of multiple turbine units aligned one after the other (Figure 1-50,
Figure 1-51). A convergent in front of the turbines is foreseen, to direct more flow
towards the turbine units. The design is scalable from approximately 25 kW to several
megawatts (Deepwater-Energy, 2013).
40
Figure 1-50: Concept of the Oryon Watermill (taken from Deepwater-Energy, 2013).
Figure 1-51:Test set-up with the Oryon Watermill (taken from Deepwater-Energy, 2013).
More information on this technology can be found on the
http://www.deepwater-energy.com and http://www.oryon.nu.
following websites:
IMDC nv
1.1.2.2.3
HydroQuest
The French company HydroQuest develops the HydroQuest©, a cross-flow turbine,
evolved from the Darreius and Gorlov turbines (HydroQuest, 2013). The design originated
from the HARVEST project, lead by the Grenoble Institut National Polytechnique
(Grenoble-INP). The HydroQuest has a “modular concept that can be adapted to any river
profile with a draft of at least 2 m” (HydroQuest, 2013). It consists of two counterrotating columns, and depending on the site, it can have a rater power of up to 200 kW
(HydroQuest, 2013). Arrays of HydroQuest turbines, fixed to floating barges, are possible
(Figure 1-53).
41
Figure 1-52: HydroQuest concept
(taken from HydroQuest, 2013).
Figure 1-53: HydroQuest turbine fixed to a floating
barge (taken from HydroQuest, 2013).
In spring 2014, a prototype will be installed in the Loire River.
The company’s website gives more information: http://www.hydroquest.net.
IMDC nv
1.1.2.2.4
Tidal Energy Pty Ltd
The Australian company Tidal Energy Pty Ltd develops the Davidson-Hill turbine, that is
fitted with a so-called Venturi shroud. According to Tidal Energy (2013), “the shroud
allows the turbine to achieve at least 3 times the power output over the same turbine
without the shroud.” The design is scalable from 1.5 m to 10 m in diameter, and can be
‘flat packed’ for shipping (Figure 1-54). Figure 1-55 shows an assembled Davidson-Hill
turbine.
Figure 1-54: Dismantled Davidson-Hill
turbine (taken from Tidal Energy, 2013).
Figure 1-55: Assembled Davidson-Hill
turbine (taken from Tidal Energy, 2013).
According to Tidal Energy (2013), a 1.5 m rotor delivers 4.6 kW at 2 m/s, up to 120 kW
at 6 m/s. For a 10 m rotor, this is 200 kW up to 5.5 MW for the same water velocities.
Regarding installation requirements, the depth of water should be approximately twice
and the width of the flow approximately four times the rotor diameter.
The turbine is mounted on a support structure with a yawing mechanism, so it can align
itself along the current. This concept is depicted in Figure 1-56.
Figure 1-56: Davidson-Hill turbine mounted on the support structure (taken from Tidal
Energy, 2013).
More details can be found on the following website: http://www.tidalenergy.net.au.
42
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1.1.2.3 Horizontal cross-axis turbines
1.1.2.3.1
Kepler Energy Ltd.
Kepler Energy Ltd., an English company, is developing the Transverse Horizontal Axis
Water Turbine (THAWT), a concept originating from the Engineering Department of the
Oxford University. Figure 1-57 shows a possible configuration of & 3-rotor THAWT turbine
assemby. The turbine requires no enveloping supporting structure, leading to a lower
parasitic drag and hence low power losses (Kepler Energy, 2013). A 1:20 scale model of
the rotor has been tested in the flume of Newcastle University (Figure 1-58).
43
Figure 1-57: Concept of the THAWT (taken from
Kepler Energy, 2013).
Figure 1-58: Scale model (1:20) of
the rotor (taken from Kepler
Energy, 2013).
According to Kepler Energy (2013), “the transverse horizontal axis configuration works
equally well with flows from either direction and hence requires no adjustments as the
tide changes direction”. Also, “the turbine is scalable to suit different marine sites”. A
rotor would typically be 10 m in diameter and 60 m long in a tidal flow with a mean
depths of 20 m. Flume tests on a scale model showed that a 10 m diameter rotor with a
length of 125 m – two turbines with one generator – would generate more than 4.4 MW
at a water velocity of 2 m/s, and more than 5.3 MW when the velocity would be 2.5 m/s
(Kepler Energy, 2013). However, “the unit will operate with reasonable efficiency at low
water velocties” (Kepler Energy, 2013).
The company website gives more information: http://www.keplerenergy.co.uk.
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1.1.2.3.2
OceanRenewable Power Company
The American company Ocean Renewable Power Company (ORPC) develops different
types of power systems, all based on the same principle of their proprietary Turbine
Generator Unit (TGU), which is shown in Figure 1-59. The TGU consists of foils that rotate
around a horizontal axis, perpendicular to the flow direction.
Figure 1-59: Turbine Generator Unit
(taken from ORPC, 2013).
Figure 1-60: RivGen® Power System (taken
from ORPC, 2013).
The TGU has a modular design, is scalable and can be stacked in groups, depending on
the site conditions. The RivGen™ Power System (Figure 1-60) aims at generating
electricity at small river sites. It is designed to be connected to a diesel-electric grid, and
is provided with automatic fuel-switching, balancing the power delivery by the RivGen™
Power System and the diesel generator. A RivGen™ Power System can consist of up to
several dozen TGUs, each TGU generating up to 25 kW at 2.25 m/s.
The TidGen™ Power System, that is depicted in Figure 1-61, is designed to generate
electricity at shallow tidal and deep river sites. The system is larger and more powerful
than the RivGen™ system, with each TGU having a rated capacity of 150 kW. In August
2012, the company completed the installation of the first grid-connected TidGen® Power
System. Finally, in the OCGen® Power System (Figure 1-62), up to four TGUs are stacked
vertically to create larger power generating modules, that can be combined horizontally
into a larger subsurface floating system. One module of four TGUs will have a peak
generating capacity of 600 kW in a 6 knot current (approx. 3 m/s).
Figure 1-61: TidGen® Power System (taken from ORPC, 2013).
Figure 1-62: OCGen®
Power System (taken
from ORPC, 2013).
The company’s website gives more information on the technology and projects:
http://www.orpc.co.
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1.1.2.4 Marine current turbines using drag forces
1.1.2.4.1
Atlantisstrom GmbH & CoKG
Atlantisstrom GmbH & CoKG, based in Germany, is developing a horizontal axis drag force
based turbine. The axis is perpendicular to the current; the patented folding mechanism
of the rotor blades “facilitates the exploitation of the incoming and outgoing tide
automatically, without switching procedures” (Atlantisstrom, 2013). The rotor blades
hence position themselves in an optimal way, lowering the hydraulic resistance when
moving in the direction opposite of the current. The rotation speed is only 7 rpm, which
probably results in a very low impact – if any – on aquatic fauna.
From prototype tests, conducted by the Pfleiderer Institute for Fluid Machinery of
Braunschweig Technical University, an optimal number of 5 drop-shaped vanes of 20 m
length were identified as resulting in the highest effectiveness (see Figure 1-63 for an
example of a 1:10 prototype test). These vanes are placed between two metal circular
plates of 8 m diameter. The power output is around 70 kW at a current velocity of 2 m/s,
but if blocking of the channel – in which the device is installed – is increased, i.e. if the
channel is relatively more narrow compared to the width of the device, power output at
2 m/s can increase to over 200 kW. Due to the relative simplicity of the design, the
company claims a low maintenance over a lifetime of about 20 years. Figure 1-64 shows a
concept drawing of the Atlantisstrom device.
Figure 1-63: Example of a 1:10 prototype test
(taken from Atlantisstrom, 2013).
Figure 1-64: Concept drawing of the
Atlantisstrom turbine (taken from
Atlantisstrom, 2013).
More information on the device and planned tests, can be found on the company website:
http://www.atlantisstrom.de.
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1.1.2.4.2
Eco Hydro Energy Ltd.
The Canadian company Eco Hydro Energy Ltd. develops the Floating Power Station (FPS),
horizontal axis turbines that are installed inline in the river course. The turbines are
characterized by the special blade design. The GR-40 model is fitted with long blades,
protruding from the rotating axis into the water (Figure 1-65). The blades’ pitch is
adjusted according to their relative position in the rotation cycle of the rotor, so as to
minimize resistance when rotating in the adverse direction of the river flow (Figure 1-66).
The optimal water flow velocity is about 1.5 m/s (EHE, 2005).
Figure 1-65: Prototype of the GR-40
with the protruding blades (taken
from EHE, 2005).
Figure 1-66: Blade pitch adjustment according to
their relative position in the rotation cycle of the
rotor (taken from EHE, 2005).
The company also applies spoon-shaped blades for their FPS. The blades unfold when
they have to capture the momentum of the water flow, but close when moving against
the current. Figure 1-67 depicts a prototype.
Figure 1-67: Floating Power Station with spoon-shaped blades (taken from EHE, 2005).
The
following
website
gives
http://www.ecohydroenergy.net.
more
information
on
this
technology:
46
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1.1.2.4.3
Hales Water Turbines Ltd.
The English company Hales Water Turbines Ltd. develops a side drive turbine with vertical
axis (Figure 1-68). The blades automatically rotate to position themselves optimally,
depending on their position relative to the current. The large blade area results in a high
torque at low speeds, i.e. 10-16 rpm, and makes that the turbine can “operate
successfully in water flows between 1-2 m/s” (HWT, 2013). Coupled with a modern
permanent magnet generator, the Hales turbine can start producing electricity from
rotations as low as 2 rpm (HWT, 2013). A ducted variant is being investigated as well
(Figure 1-69).
47
Figure 1-68: Hales Water Turbine
(taken from HWT, 2013).
Figure 1-69: Venturi ducted Hales Turbine. (taken
from HWT, 2013).
The company’s website gives more information: http://www.hales-turbine.co.uk.
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1.1.2.4.4
Neptune Renewable Energy Ltd.
Neptune Renewable Energy Ltd., an English company, was developing the Proteus, a
floating ducted vertical axis turbine, using drag forces (Figure 1-70). A full scale
demonstrator was deployed in the Humber estuary in January 2012 (Figure 1-71).
Unfortunately, on 7 February 2013, the company stated to go into liquidation.
Figure 1-70: Proteus concept (Neptune
Renewable Energy, 2011).
Figure 1-71: Full scale prototype moored in the
Humber. (Photograph: Sean Spencer/Hull News
& Pictures, 2013).
More information on the reasons for this liquidation can be found on the following
website: http://www.neptunerenewableenergy.com.
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1.1.2.4.5
S.A. Rutten
The company S.A. Rutten is based in Herstal, near Liège, in Belgium, once was developing
a turbine concept as well (Figure 1-72). The concept consisted of a twin tubular pontoon
with a floating turbine and a straight bladed waterwheel, that was tested in Zaire (the
current Democratic Republic Congo)(Khan, 2006). The company still exists, but produces
centrifugal turbine wheels (http://www.ruttensb.com).
49
Figure 1-72: Rutten waterwheel (taken from Khan, 2006).
1.1.2.4.6
Sea Power International AB
The Swedish company Sea Power International AB developed a drag force based vertical
axis turbine, called the EXIM turbine (Figure 1-73). Tests were conducted at sites off the
Shetland Islands (Water Power & Dam Construction, 2003). However no additional data
can be found, hence it seems it never passed the prototype stage.
Figure 1-73: EXIM turbine (taken from Water Power & Dam Construction, 2003).
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1.1.2.4.7
Tideng
The Danish Tideng develops a horizontal cross axis turbine based on drag forces. The six
rotor wings are extended via a guided line when they are able to catch the current, and
withdrawn when they are turning opposite the current’s direction, so as to minimize
resistance. The principle can be seen in Figure 1-74. Figure 1-75 shows an image from a
lab test.
The turbine base will be built in concrete, and can be towed. When the base has to be
lowered, it is filled with water. When properly in position, it will be filled with sand to
increase the weight.
50
Figure 1-74: Concept of the Tideng
rotor (taken from Tideng, 2013).
Figure 1-75: Tideng lab test (taken from
Tideng, 2013).
More information on this technology can be found on: http://www.tideng.com.
1.1.2.4.8
Other
Aquaphile sarl, as already explained in §1.1.1.1.3 (p. 14), offers ‘taylor made’ paddle
wheel current turbines, applicable in situations with very low depth or very turbulent flow
(Aquaphile, 2013).
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1.1.3 OTHER TECHNIQUES
1.1.3.1 Rotation
1.1.3.1.1
Flumill AS
The Norwegian company Flumill AS is currently developing the Flumill System, a device
existing from two counter-rotating helixes. The helixes are buoyant, enabling them to
automatically adjust their operational angle according to the water flow (between 25 and
50°), which results in a low load on the foundation. The dual helixes are made from
composite material for reasons of durability, strength and cost reduction.
According to the manufacturer, “the outer edge of the helix will be restricted by the speed
of the water, thus creating no harm to marine fauna” (Flumill, 2013). Furthermore, “the
design gives low turbulence and no cavitation” (Flumill, 2013). This lower turbulence
should enable more concentrated tidal parks. The Flumill System can operate in tidal
streams as low as 1 m/s.
51
Figure 1-76: Concept of the
Flumill System (taken from
Flumill, 2013).
Figure 1-77: Flumill helix (taken from Flumill, 2013).
The generator and other equipment is housed in a watertight compartment at the bottom
of the helixes. The system has undergone a wide range of tests, from CFD simulations
through tank, tow and pilot test to successful testing at the EMEC (for more information
on the EMEC, see §2.3). The next step would be to deploy a full-scale pilot in Rystraumen,
neer Tromsoe in northern Norway (Flumill, 2013).
More information on this technology can be found on the company’s website:
http://www.flumill.com.
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1.1.3.2 Oscillation and transverse motion
1.1.3.2.1
Aqua Energy Solutions
Aqua Energy Solutions, a Norwegian company, develops an energy conversion device that
consists of blades fitted on a chain, that is installed perpendicularly to the flow (Figure
1-78). The flow causes the blades, and thus the chain, to move transversally. This
movement is converted into electricity by generators.
52
Figure 1-78: Concept of the AES design (taken from AES, 2013).
The AES design “has undergone ‘proof-of-concept’ testing, analysis and CFD simulations
and a 3rd party verification“ (AES, 2013). Currently the company is planning to build a
second prototype, which would be a scaled down 120 kW. According to AES (2013), “a full
size tidal power plant is expected to exceed 6 MW – in nominal currents.”
On the company website more information can be found: http://www.aquaenergy.no.
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1.1.3.2.2
BioPower Systems
The Australian Biopower Systems is currently developing the bioSTREAM™, a hydrofoil
system that resembles the tail fin of a fish (Figure 1-79). “An onboard computer
continually adjusts the angle of the hydrofoil (fin) relative to the oncoming flow such that
the tail and fin system develops a swimming motion. The energy transferred by this sideto-side motion is converted to electricity by O-Drive™ modules installed on the
bioSTREAM™.” (BioPower Systems, 2013).
Figure 1-79: Concept of the bioSTREAM™ (taken from BioPower Systems, 2013).
The system should be a “commercially viable source of electricity” for sites having a peak
current speed of at least 2.5 m/s (BioPower Systems, 2013). Currently a 250 kW
demonstration project is being developed.
The company website offers additional information: http://www.biopowersystems.com.
The company also develops the bioWAVE™ technology, to produce electricity from wave
energy.
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1.1.3.2.3
IHC Engineering Business Ltd.
The English company The Engineering Business Ltd. was developing a vertically oscillating
hydrofoil called the Stingray (Figure 1-80). The forces acting on the horizontal wing are
comparable to those causing a airplane to lift. While moving upwards, a downward force is
exerted on the wing, pulling it down again. The device was tested at Yell Sound off
Shetland in 2002 (Figure 1-81). The rated power at 1.5 m/s and above was 150 kW for
the 15.5 m wide hydroplane (EB, 2003).
54
Figure 1-80: Stingray mechanical general
arrangement (taken from EB, 2003).
Figure 1-81: Prototype of the Stingray
(taken from Tethys, 2013).
The Engineering Business Ltd. was taken over by IHC Merwede, creating the company IHC
Engineering Business. At the moment of writing it is unclear whether IHC is further
developing the Stingray concept.
More information on the Stingray can be found in EB (2002), EB (2003) and EB (2005).
The company website is: http://www.engb.com.
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1.1.3.2.4
Pulse Tidal
The English company Pulse Tidal develops the Pulse Stream machine, a multi-bladed
hydrofoil turbine (Figure 1-82). Already in May 2009, the company deployed the 100 kW
PS100 in the Humber river (Figure 1-83).
55
Figure 1-82: Concept of the Pulse Stream (taken from
Pulse Tidal, 2013).
Figure 1-83: PS100 in the
Humber river (taken from Pulse
Tidal, 2013).
According to Pulse Tidal (2013), one of the main advantages of their technology is the
applicability in shallow waters, making the installation and maintenance more
straightforward. Commercial scale devices – nominal power of 1 MW and more – could be
deployed “in water as shallow as 20 m” (Pulse Tidal, 2013). The machine is buoyant, so it
can be “fully assembled and commissioned onshore before floating out for installation”
(Pulse Tidal, 2013).
More information can be found on the company website: http://www.pulsetidal.com.
IMDC nv
1.1.3.2.5
Robert Gordon University
van Berkel (2013) also lists the Sea Snail concept, developed by The Robert Gordon
University (RGU) of Aberdeen, Scotland. The Sea Snail is no energy converter, but a
support structure for e.g. seabed mounted tidal current turbines. Conventional attaching
of structures to the seabed often involves drilling or piling, which considerably disturbs
benthic flora and fauna. Gravity based foundations require considerable amounts of mass,
necessitating large and heavy equipment to deploy and recover the structure.
Figure 1-84: Sea Snail (taken from RGU, 2013).
The Sea Snail aims at eliminating these concerns, by making use of hydrofoils on the
structure. The foils are positioned in such a way that the current exerts a downward force
on them. When the flow increases, the overturning moment on the turbine increases but
so does the downward force on the hydrofoils, resulting in a stable support structure for
marine current turbines.
“An omnidirectional version with greatly reduced fabrication costs” will be demonstrated
soon (RGU, 2013). More information on the concept is given on RGU’s website:
http://www4.rgu.ac.uk/cree/general/page.cfm?pge=10769.
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1.1.3.2.6
Tidal Sails AS
The Norwegian Tidal Sails AS, founded in 2004, develops underwater sails, that are
suspended perpendicular to the flow on cable works (Figure 1-85). The flow causes the
chain of sails to move horizontally. According to Tidal Sails (2013), the system can be
applied “in slow moving waters such as e.g. the Gulf Stream, the Amazon or Yangtze
River”. The motion drives a generator that converts the mechanical energy into electricity.
A pilot installation allegedly produced 28 kW (Mead, 2013).
Figure 1-85: Concept of the Tidal Sails (taken from Tidal Sails, 2013).
The Tidal Sails AS website (http://tidalsails.com) was inactive at the time of writing
(17 december 2013). The website of Aqua Energy solutions is: www.aquaenergy.no.
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1.1.3.2.7
Vortex Hydro Energy
Vortex Hydro Energy, an American company, develops the VIVACE converter, a device
using vortex induced vibrations to convert kinetic energy into electricity. Horizontal
cylinders are positioned perpendicular to the flow, and the flow passing these cylinders
creates vortices downstream of the cylinder, that result in a vertical oscillation. This
vertical motion is transformed into electricity by a generator. This principle is depicted in
Figure 1-86.
Figure 1-86 : Working principle of the VIVACE converter (taken from VHE, 2013).
Multiple cylinders can be installed in a single module, and several modules can be used to
create an array of devices (Figure 1-87). According to the manufacturer, the device can
harness energy from flow speeds as slow as 1-2 m/s. The cylinder oscillation frequency is
rather low, about one cycle per second, “creating no direct physical threat to fish” (VHE,
2013).
58
Figure 1-87: Concept of an array of VIVACE converters (taken from VHE, 2013).
The company’s website gives more information on the operating principle and ongoing
tests and developments: http://www.vortexhydroenergy.com.
1.1.3.2.8
Other
Atlantis Resources, as already explained in §1.1.1.1.5 (p. 16), develops the AN series,
shallow water turbines using “Aquafoils™ to capture momentum from the flow of water to
drive a chain perpendicular to the flow.” (Atlantis Resources, 2013).
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1.2 TIDAL BARRAGES
A tidal barrage is a closure of a reach that is influenced by the tide. As the tide comes in,
the barrage is open and water flows in the tidal basin behind the barrage. During low tide,
the excess water in the basin is released again, the flow being directed along turbines.
The principle is shown in Figure 1-88. Other configurations are possible as well, in which
power is generated by utilizing the incoming tide, or a combination of high and low tide.
The scheme in Figure 1-88 shows a bulb turbine, but other turbines are possible as well.
Figure 1-88: Operating principle of a tidal barrage (taken from ESRU, 2002).
The currently largest tidal power plant is the Sihwa Lake Tidal Power plant in South Korea,
with an installed capacity of 255 MW (van Berkel, 2013). The overall configuration has not
changed significantly through time, since the plant also makes use of bulb turbines.
According to ESRU (2002), the tidal difference should exceed 5 m for a barrage to be
feasible. Civil costs are very high, and the construction phase will take years. Another
important issue regarding tidal barrages is the impact on marine fauna and flora. Of
course there is the elevated risk for migrating marine fauna to collide with the rotor
blades. On a larger scale, the barrage will change the inland tidal environment. For
instance, the Rance plant in France caused a change in the composition of the fish
population (Retiere, 1994).
To lower the risk of collision with the rotor blades, technological solutions are being
developed. Recent turbine developments are focussing strongly on this ‘fish-friendliness’.
One example of such a development is the improvements on the rotor design by Pentair
Fairbanks Nijhuis together with FishFlow Innovations, two Dutch companies. An example
of such an improved rotor design can be seen in Figure 1-89.
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Figure 1-89: Rotor design optimization to improve fish-friendliness (Pentair Fairbanks
Nijhuis, 2012).
Another development that looks promising is the aerated siphon, in which the energy is
transferred to a second medium, being air. The main operating principle relies on the
Venturi-principle: water flowing through an inverted U-tube causes a pressure drop. This
pressure difference is created over a conventional gas turbine, resulting in rotations of the
latter (Figure 1-90). Since the rotations of the gas turbine occur at a much higher rate,
the turbine is less expensive (van Berkel, 2013). This technology removes the chance of
fish being hit by rotating parts, when passing the turbine.
Figure 1-90: Aerated siphon turbine.
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2
KNOWN INITIATIVES IN NORTH WEST EUROPE
This chapter focuses on the known initiatives, on project scale, in North West Europe. As
with the overview of technologies, this list might not be exhaustive, as new initiatives are
constantly emerging.
2.1 MARINET
The Marine Renewables Infrastructure Network (MARINET), is a network of research
centres and organisations that are working together to accelerate the development of
marine renewable energy technologies – wave, tidal and offshore-wind. It is co-financed
by the European Commission (FP7) specifically to enhance integration and utilisation of
European marine renewable energy research infrastructures and expertise. MARINET
offers periods of free-of-charge access to world-class R&D facilities and expertise and
conducts joint activities in parallel to standardise testing, improve testing capabilities and
enhance training and networking.
Figure 2-1 shows a map with the available facilities. More information on the network can
be found on: http://www.fp7-marinet.eu.
61
Figure 2-1: Overview of facilities participating in MARINET (taken from MARINET, 2013).
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2.2 SEA GENERATION
Sea Generation Ltd. (http://www.seageneration.co.uk) is the project company which is a
wholly owned subsidiary of Marine Current Turbines Ltd., which in turn is wholly owned by
Siemens in 2012. In the SeaGen project, a 1.2 MW version large-scale tidal current
turbine, SeaGen S (Figure 2-2), was installed in Strangford Lough, Northern Ireland, UK.
Its first operation was in July 2008.
62
Figure 2-2: Drawing of the SeaGen S turbine (MCT, 2013).
The project is part funded (50%) by the UK Department for Business (Department of
Trade and Industry until June 2007). The other part of the funding comes from private
and corporate investors “who are keen to see the technology become a key element of
any renewable energy project around the UK in the future”.
The SeaGen S system consists of twin power trains mounted on a cross beam, that can be
raised above the water for routine maintenance, by winching it up the monopole support
structure, as can be seen in Figure 2-3. According to MCT (2013), the system generates
rated power for water flow velocities of greater than 2.4 m/s, and it “is capable of
delivering up to [...] 6000 MWh per year”, which corresponds to the rate of energy
capture of a 2.4 MW wind turbine.
The turbine has been tested and the environment monitored extensively. From these
tests, a number of changes will be implemented in the next turbine, the SeaGen S Mk 2.
Most importantly, the Mk 2 is scaled up to 2.0 MW, with an increased rotor diameter of
20 m.
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Figure 2-3: SeaGen S with the cross beam raised above the water (MCT, 2013).
The next step would be to develop an array of similar turbines. For this, a joint venture
between ‘Marine Current Turbines Ltd.’ and ‘RWE npower renewables’ was set up, named
‘SeaGeneration (Wales) Ltd.’. The project is named the ‘Skerries Tidal Stream Array’, and
will consist of five 2 MW turbines, resulting in an electricity supply for 10 000 homes.
63
Figure 2-4: Array area and cable corridor options for the Skerries Tidal Stream Array
(Sea Generation (Wales), 2013).
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A very similar project will be developed between the Isle of Skye and the west coast of
Scotland,
at
the
Kyle
Rhea
site.
For
this,
the
development
company
‘SeaGeneration (Kyle Rhea) Ltd.’ was set up. Figure 2-5 shows a map of the project area.
64
Figure 2-5: Project area for the Kyle Rhea Tidal Stream Array project
(Royal HaskoningDHV, 2012).
2.3 PENTLAND FIRTH AND ORKNEY WATERS MARINE ENERGY PARK
According to the Pentland Firth and Orkney Waters Leadership Forum, “the Pentland Firth
and Orkney Waters around the North of Scotland are home to some of the world’s best
wave and tidal energy resources”. The mission statement of the Leadership Forum, which
is a public/private group is “[to work] together to lead the effective and timely delivery of
up to 1.6 GW of wave and tidal energy in the Pentland Firth and Orkney Waters by 2020,
and in doing so, supporting the creation of a new, commercial scale marine energy
industry and secure maximum economic and social benefit for Caithness, Orkney, the
wider Highlands and Islands, and Scotland”. An overview of the Marine Energy Park can
be seen in Figure 2-6.
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65
Figure 2-6: Overview of the Pentland Firth and Orkney Waters Marine Energy Park:
Round 1 Development Sites (HI-marine energy park, 2012).
The European Marine Energy Centre (EMEC) – a test facility for full scale prototype marine
energy devices is situated in the park as well. EMEC, which is spread over five sites across
Orkney, offers open-sea testing facilities. The full scale test sites, one for wave energy
and one for tidal current energy, are connected to the UK national grid through a subsea
cable. The centre also operates two scale test sites with less challenging conditions, for
testing smaller scale devices. These sites have berths with moorings, foundations for
wave and tidal devices, specially designed test support buoys for electricity dissipation
and remote communications with the device, and an area of seabed for rehearsal of
deployment techniques. The EMEC also gathers weather, wave and tidal data from each
site (EMEC, 2013).
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2.4 THE NETHERLANDS
The Tidal Testing Centre (TTC) is situated in Den Oever, The Netherlands. The centre is
part of MARINET (§2.1), and is located next to the sluice complex connecting Lake Ijssel
to the Wadden Sea (Figure 2-7). Its main function is to discharge water from the lake to
the Wadden Sea, twice a day. In the sluice water flows up to 5 m/s are reached.
According to TTC (2013), the sluice is “ideal for intermediate scale [1:3] testing of
offshore devices” and “1:1 scale testing of small in river power units”. A grid connection is
available as well as other services such as data acquisition services, engineering support
or office space.
66
Figure 2-7: Sluice at the Tidal Testing Centre in Den Oever (taken from TTC, 2013).
Besides the sluice, the TTC also offers the possibility of performing tow tests at large scale
through still open water by sailing a barge on Lake IJssel, for turbines with a diameter up
to 4 m (TTC, 2013). Up to 100 kW can be dissipated on board. At the Wadden Sea,
diameters up to 10 m are possible.
Figure 2-8: Tow test at the Tidal Testing Centre in Den Oever (taken from TTC, 2013).
Finally, the TTC is currently developing an offshore site for testing, with a flow of about
1.8 m/s and depths up to 30 m, to accommodate larger size turbines.
More information on the TTC can be found on their website: http://tidaltesting.nl.
IMDC nv
2.5 FRANCE
France was the first country to built a tidal barrage, on the estuary of the Rance river,
near Saint-Malo, France, in 1966. Figure 2-9 shows an aerial view. According to van
Berkel (2013), the Rance plant is fitted with ten bulb turbines with a rotor diameter of
5.4 m. With a tidal difference of 6 m and a basin surface of 22.5 km2, this results in a
total capacity of 240 MW. EDF (2013), the operator of the plant, states that the Rance
plant accounts for 90% of the electricity generated in Brittany.
67
Figure 2-9: Tidal power plant on the Rance river in Saint-Malo, France (taken from
INFORSE, 2013).
Figure 2-10 shows a cross section of the plant. The bulb turbines can work in both
directions of flow; also they can be as pumps e.g. to store water in the basin to anticipate
expected power consumption (ESRU, 2002).
Figure 2-10: Operating principle of the tidal energy plant in the Rance (taken from Frers,
2005).
IMDC nv
3
PRO-TIDE PROJECTS
In this chapter the project of each PRO-TIDE partner is briefly described. More information
on the different projects can be found in the related PRO-TIDE reports.
3.1 PROVINCE OF ZEELAND
Originally Lake Grevelingen, situated in the south-western part of The Netherlands (Figure
3-1) was part of the Scheldt estuary. However after the heavy and fatal floods in 1953, it
was decided to close large parts of the Scheldt estuary using a combination of mobile and
immobile storm surge barriers, in order to protect the low-lying land in the Province of
Zeeland. So currently the so-called Brouwersdam separates Lake Grevelingen from the
North Sea (Figure 3-2).
Brouwersdam
68
Figure 3-1: Location of Lake
Grevelingen in The Netherlands.
Figure 3-2: Brouwersdam separating Lake
Grevelingen from the North Sea.
Because of this cut-off, oxygen levels in the lake have become critically low through the
course of time. Studies have shown that re-enabling a tidal variation in the lake will
increase oxygen levels resulting in a total recovery of soil life, and this within six years
after re-establishing a tidal difference. Therefore, the decision has been made to
(partially) open the Brouwersdam, however without compromising its primary protective
function. This re-opening of the Brouwersdam offers opportunities for constructing a tidal
barrage.
For the Province of Zeeland the PRO-TIDE project is the first of three phases to construct
this tidal barrage. In the project, first a desktop study of suitable technologies is
performed, primarily – but not solely – focussing on low-head performance, capital and
operational expenditures, and fish-friendliness. Figure 3-3 and Figure 3-4 show two
concepts. Afterwards, pilot tests in laboratory conditions will take place. The project also
IMDC nv
aims at developing the necessary know-how on private-public partnerships, essential in
funding a project of this scale.
Figure 3-3: Concept of a bulb turbine as
possible turbine for the Brouwersdam.
Figure 3-4: Concept of a siphon turbine
as possible turbine for the Brouwersdam.
In the second phase the Tidal Test Centre Grevelingen will be established. One unit of the
tidal barrage will be designed, constructed and tested on-site. The experience and results
from this Tidal Test Centre will undoubtedly be highly valuable in developing the third and
final phase, i.e. the construction of a full tidal barrage in the Brouwersdam.
69
IMDC nv
3.2 PORT OF DOVER
Within the PRO-TIDE project, the Port of Dover is investigating the feasibility of a tidal
energy power station, including testing smaller scale devices in a commercial location.
The feasibility will cover the economical, environmental and practical aspects of a small
scale array. The port is one of the world’s busiest international ferry ports with a high
number of vessel movements and vital navigational areas. Consequently the location of
any pilot device was restricted to certain areas which would not interfere with the Ports
commercial operations. A tidal investigation zone of approximately 0.45 km2 outside the
Southern Breakwater was identified (Figure 3-5). The depths are relatively shallow
ranging from 12 m at the near shore to 17 m at the seaward end at Chart Datum. The
flow speed is estimated to be between 2-2.5 m/s.
70
Figure 3-5 : Tidal energy investigation zone of the Port of Dover.
The first phase of the project is an initial desktop feasibility exercise investigating the
environmental conditions of the site, understanding the ecology, tidal flow and
technological requirements. This information will help determine what types of devices will
be suitable and what the requirements are regarding consents, licences and approvals.
With the support of PRO-TIDE, the Port of Dover started scouting for locations with the
most ideal tidal flow rate. The predictability of that flow rate is also important. By
modelling the area, they were able to identify two tidal energy ‘sweet spots’.
Measurements are being performed to check if the calculations of the modelling are
IMDC nv
correct. These measurements are executed by LOG, another PRO-TIDE partner (see
§3.4).
Meanwhile, the Port of Dover is going through a long list of manufacturers to see which
devices are most suitable for use in the harbour area. Important is that the manufacturers
can not only deliver a usable device, but also deliver within the correct timeframe. This
process is ongoing, and the aim is to have three devices selected. The selection criteria
are:
Size: operation possible in a depth of 12 m
Ease of access and removal for maintenance
Maintenance frequency
Maintenance support requirements
Sensitivity to undersea fouling – marine growth or debris
Electrical output and connection
Fixing: piled, gravity based, tethered floating or tethered mid-stream
The next step will be to test the selected devices. This will enable further assessment of
the device performance, environmental implications and compatibility to the site. The pilot
study is expected to inform future maintenance requirements as well as an understanding
of the applicability of port infrastructure to energy generation. These tests are scheduled
for 2015. The results of the pilot should answer three important questions:
Does the system generate power?
Which of the three systems performs best?
Are the devices cost effective?
An economic business case will be conducted, answering the last question.
71
IMDC nv
3.3 ISLE OF WIGHT
The Isle of Wight is an ideal location to develop a marine energy centre to complement
the existing test and support infrastructure available within the UK, the Perpetuus Tidal
Energy Centre (PTEC), formerly called Solent Ocean Energy Centre (SOEC). With a rich
and diverse tidal resource in physically protected waters, the PTEC is suitable for a wide
range of tidal technologies and testing parameters. PTEC will offer this and provide an
asset that will allow users to achieve the technology readiness level and certifications
necessary for the commercialisation and large-scale production of tidal energy.
Hence the Isle of Wight aims at developing a project similar to the EMEC. The site will be
suitable for up to full-scale single units and for small arrays of devices from prototypes to
pre-commercial demonstrators. The main site characteristics are:
grid-connected
depth range of 30-80 m
mean spring peak velocity of 2.6-2.9 m/s at surface
relatively sheltered.
In addition, the Isle of Wight has a rich marine infrastructure and significant
manufacturing, composites and engineering capability, and there are extensive synergies
with the tidal, wave and offshore wind sectors.
The PTEC will consist of two sites: a nursery site and a development site (Figure 3-6). The
nursery site has maximal velocities of 1.5 m/s, a water depth of 10-20 m, available space
for up to 3 devices, with a total installed capacity of 1 MW. To illustrate, Figure 3-7 shows
the bathymetry of the nursery site. The development site is characterized by more
energetic conditions: a spring peak velocity of about 3 m/s, water depths ranging from
20-60 m and space for single devices or small arrays, with a total installed capacity of
20 MW. An indicate berth lay-out for the development site is shown in Figure 3-8.
72
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Figure 3-6: Location of the SOEC Nursery and Development sites.
73
Figure 3-7: Bathymetry of the SOEC
Nursery site.
Figure 3-8: Indicative berth layout at the SOEC
Development site.
More
details
of
the
project
can
be
found
at
the
following
website:
http://www.iwight.com/Residents/Environment-Planning-and-Waste/Future-EnergyInitiatives/Solent-Ocean-Energy-Centre-SOEC/Background.
IMDC nv
3.4 LABORATORY OF OCEANOLOGY AND GEOSCIENCES
Within the PRO-TIDE project, the Laboratory of Oceanology and Geosciences (LOG) of the
Université du Littoral Côte d’Opale (ULCO) will establish a standardized and repeatable
methodology for the characterization of potential deployment sites. For this, LOG develops
and applies instrumentation packages on a stationary bottom mounted tripod (Figure
3-9). The tripod contains an ADCP (Acoustic Doppler Current Profiler) for high-frequency
velocity profiling and an ADV (Acoustic Doppler Velocimeter) for obtaining high-frequency
velocity measurements in the bottom layer. Also suspended matter measurements are
possible with the laser granulometer, abd the tripod is also fitted with optical sensors and
a mini CTD (to measure conductivity, temperature and depth).
74
Figure 3-9: Experimental station developed by LOG.
Figure 3-10 shows an example of possible data output, when the tripod was deployed
west of the Boulogne harbour. The measurements took place over 12 tidal cycles,
covering the period of transition from mean spring to neap tide. The depicted Reynolds
stress is a measure of the turbulence in the flow; the turbulent kinetic energy production
rate shows the rate at which energy is transferred from the mean flow to turbulence. The
energy of the mean flow decreases when the production rate increases.
LOG can also perform high resolution current mapping using a towed current profiler
(Figure 3-11), fitted with a highly accurate positioning system. Figure 3-12 shows an
example of processed measurements: it depicts the surface currents during flood in the
Boulogne harbour.
IMDC nv
Figure 3-10: Example of measurements performed with the tripod. Deployment west of
the Boulogne harbour. Top: Velocity measurements; middle: Reynolds stress (south-north
component); bottom: turbulent kinetic energy production rate.
75
Figure 3-11: Towed current profiler.
Figure 3-12: Surface currents on flood
(HW-0.5 h) in Boulogne harbour.
Finally, LOG will also perform statistical analysis of local turbulence time series in relation
with the power production from installed test turbines, in order to characterize the nonstationarity of the power output time series.
IMDC nv
3.5 WATERWEGEN & ZEEKANAAL NV
The project of Waterwegen & Zeekanaal (W&Z), or Waterways and Seacanal in English,
consists of two topics:
investigating the feasibility of energy harvesting from potential energy at the lock
in Heusden.
investigating the possibilities of harvesting tidal energy using free flow turbines at
several locations in the Sea Scheldt.
The project is a continuation, in a more detailed way, of a previous study of W&Z, in
which the feasibility of harvesting tidal energy on the Sea Scheldt was considered in more
general terms. Different techniques were described, that are applicable at several types of
locations, such as tidal measuring stations, inlet-outlet structures or the lock to be
constructed in Heusden, that has a downstream water level influenced by the tide (IMDC,
2011). In the feasibility study regarding the lock in Heusden, the previous study is
extended by taking additionally into account the water availability around Ghent and the
hydraulics of the inlet to and outlet from the turbine. Also a conceptual design is
developed so as to estimate the civil costs in more detail (Figure 3-13).
76
Figure 3-13: Lateral view of the conceptual design of the hydropower plant at the lock in
Heusden.
IMDC nv
The second part of the W&Z project starts with assessing the tidal current energy density
in the Sea Scheldt, after which a suitable location to install a test set-up is selected
(Figure 3-14). The aim then is to have several third-party turbines installed on this
location and tested, in different phases of their development. The project focuses on
smaller-scale applications of the technology, suitable for riverine environments.
77
Figure 3-14: Selection of a suitable location for performing small-scale tidal current
turbine tests using an energy density map based on a 2D-hydrodynamic model.
IMDC nv
4
EVALUATION FRAMEWORK
This chapter explains the evaluation framework, as developed within the PRO-TIDE
project.
The evaluation framework has to take into account multiple criteria. Starting from a
proposal for the Multi Criteria Analysis (MCA) presented during the WP1 Masterclass in
Antwerp, 30 May 2013, suggestions were made. The updated MCA is given in Table 4-1.
In the MCA, each criterion is scored according to a pre-defined scale. The total score is
calculated using a weighted sum of the individual scores, the weighting factors also being
pre-defined. Of course, the number of criteria and the weighting factors can be adjusted
depending on the considered project.
Table 4-1: Example of a Multi Criteria Analysis.
MULTI CRITERIA ANALYSIS
Technology
kWh
costs
Weighting
30%
factor
Fish
friendliness
Maturity of
technology
Exportability
InnoPump
vation functiona)
Total
score
30%
20%
10%
5%
5%
100%
Tech 1
3
1
1
4
2
4
2.10
Tech 2
2
3
2
3
2
3
2.45
Tech 3
4
2
2
3
1
4
2.75
key:
a) if applicable
4
Excellent
3
Good
2
Fair
1
Bad
0
Very bad
78
IMDC nv
5
AES
(2013).
Aqua
Energy
http://www.aquaenergy.no.
REFERENCE LIST
Solutions.
Consulted
on
17 December 2013.
Alstom (2013). Tidal Power Solutions. Brochure. Retrieved 7 August 2013
http://www.alstom.com/power/renewables/ocean-energy/tidal-energy.
Andritz (2013). ANDRITZ HYDRO Hammerfest.
http://www.hammerfeststrom.com.
Consulted
on
from
30 October 2013.
Aquaphile (2013). Aquaphile sarl. Consulted on 29 October 2013. http://www.hydrogen.fr.
Aquascientific
(2013).
Aquascientific.
http://aquascientific2.moonfruit.com.
Consulted
on
30 October 2013.
Atlantis Resources (2013). Atlantis Resources Corporation Pte Limited. Consulted on
30 October 2013. http://www.atlantisresourcescorporation.com.
Atlantisstrom (2013). Atlantisstrom GmbH & CoKB. Consulted on 29 October 2013.
http://www.atlantisstrom.de.
BEC
(2013).
Blue
Energy
Canada
http://www.bluenergy.com.
Inc.
Consulted
BioPower Systems (2013). BioPower Systems.
http://www.biopowersystems.com.
Consulted
on
17 December 2013.
on
17 December 2013.
Bluewater (2013). Bluewater’s Tidal Energy Converter. Consulted on 28 October 2013.
http://www.bluewater.com/new-energy/bluetec.
Calgano G. & Moroso A. (2007). The Kobold marine turbine: from the testing model to the
full scale prototype. Presentation at the Tidal Energy Summit, London, UK, 28-29
November 2007.
Clean Current (2013). Clean Current Power Systems Incorporated. Consulted on
30 October 2013. http://www.cleancurrent.com.
Deepwater-Energy (2013). Deepwater-Energy
http://www.deepwater-energy.com.
BV.
Consulted
on
30 October 2013.
EB (2002). Research and Development of a 150 kW Tidal Stream Generator. The
Engineering Business Ltd. Work carried out under contract as part of the UK
Department of Trade
and Industry Sustainable
Energy Programmes.
ETSU T/06/00211/00/REP, DTI pub URN no 02/1400.
EB (2003). Stingray Tidal Stream Energy Device – Phase 2. The Engineering Business Ltd.
Work carried out under contract as part of the UK Department of Trade and
Industry Sustainable Energy Programmes. T/06/00218/00/REP, URN 03/1433.
EB (2005). Stingray Tidal Stream Energy Device – Phase 3. The Engineering Business Ltd.
Work carried out under contract as part of the UK Department of Trade and
Industry Sustainable Energy Programmes. T/06/00230/00/REP, URN 05/864.
79
IMDC nv
EDF
(2013).
Electricité
de
France.
Consulted
on
19 December 2013.
http://businesses.edf.com/generation/hydropower-and-renewable-energy/marineenergies/our-strategy-43776.html.
EHE
(2005).
Eco
Hydro
Energy
http://www.ecohydroenergy.net.
EMEC
(2013). European Marine
http://www.emec.org.uk.
Ltd.
Energy
Consulted
Centre.
on
Consulted
17 December 2013.
on
12 July 2013.
Frers C. (2005). El planeta Tierra se está calentando. Consulted on 4 November 2013.
http://www.tiempo.com/ram/1886/el-planeta-tierra-se-est-calentando.
HI-marine energy park (2012). Brochure. Retrieved 12 July 2012 from http://www.hienergy.org.uk/hi-marine-energy-park.htm.
HWT (2013). Hales Water Turbines Ltd. Consulted on 29 October 2013. http://www.halesturbines.co.uk.
HydroQuest
(2013).
HydroQuest.
http://www.hydroquest.net.
Consulted
on
30 October 2013.
IHC (2012). IHC Tidal Energy – The never ending energy. Brochure, November 2012.
IMDC (2011). Getijdenenergie op de Zeeschelde – dossier Interreg: Haalbaarheidsstudie
(in Dutch). Final report. Study commissioned by Waterwegen en Zeekanaal NV,
Department Sea Scheldt. I/RA/11372/11.071/TGO.
INFORSE (2013). International Network for Sustainable Energy. Consulted
4 November 2013. http://www.inforse.dk/europe/dieret/Hydro/hydro.html.
Kepler
Energy (2013). Kepler
http://keplerenergy.co.uk.
Energy
Ltd.
Consulted
on
on
19 December 2013.
Khan J. (2006). State of River Energy Technology. White paper, Powertech Labs, British
Columbia,
Canada.
Downloadable
from
http://hydrovolts.com/wpcontent/uploads/2011/06/In-Stream-Hydrokinetic-White-Paper2.pdf.
Lunar
Energy
(2013).
Lunar
http://www.lunarenergy.co.uk.
Energy.
Consulted
MARINET (2013). Marine Renewables Infrastructure
18 December 2013. http://www.fp7-marinet.eu.
on
Network.
30 October 2013.
Consulted
on
ESRU (2002). Renewables in Scotland. Energy Systems Research Unit, Universtity of
Strathclyde.
Consulted
on
19 December 2013.
http://www.esru.strath.ac.uk/EandE/Web_sites/01-02/RE_info/index.htm.
ESRU (2006). Marine Current Resource and Technology Methodology. Energy Systems
Research Unit, University of Strathclyde. Consulted on 17 December 2013.
http://www.esru.strath.ac.uk/EandE/Web_sites/0506/marine_renewables/home/welcome.htm.
80
IMDC nv
MCT
(2013).
Marine
Current
Turbines.
http://www.marineturbines.com.
Consulted
on
12
July
2013.
Mead D. (2013). How Tidal Sail Generators Could Be More Efficient. Motherboard online
magazine.
Consulted
on
17 December 2013.
http://motherboard.vice.com/blog/how-tidal-sail-generators-could-be-moreefficient.
NaREC (2013). National Renewable Energy Centre Corporate brochure. Retrieved 7
August 2013 from http://www.narec.co.uk/corporate.
Nautricity
(2013).
Nautricity
http://www.nautricity.com.
Ltd.
Consulted
Neptune
Renewable
Energy
(2011).
Consulted
http://www.neptunerenewableenergy.com.
on
on
28 October 2013.
20
June
2011.
OCRP (2013). Ocean Renewable Power Company. Consulted on 30 October 2013.
http://www.orpc.co.
OEL
(2013).
Oceanflow
Energy
Ltd.
http://www.oceanflowenergy.com.
Open
Hydro
(2013).
Open
http://www.openhydro.com.
Hydro.
Consulted
Consulted
on
7
on
August
2013..
30 October 2013.
Pentair Fairbanks Nijhuis (2013). Pentair Fairbanks Nijhuis’ lage druk visvriendelijke hydro
turbine – i.s.m. FishFlow Innovations (in Dutch). October 2012.
Pulse
Tidal
(2013).
Pulse
http://www.pulsetidal.com.
Tidal.
Consulted
on
19 December 2013.
Retiere C. (1994). Tidal power and the aquatic environment of La Rance. Biol. J. Linn.
Soc., 51(1-2), 25-36.
RGU (2013). Prototype support structure for seabed mounted tidal current turbines (The
Sea Snail). Robert Gordon University, Aberdeen, UK. Consulted on
17 December 2013. http://www4.rgu.ac.uk/cree/general/page.cfm?pge=10769
Royal HaskoningDHV (2012). The Kyle Rhea Tidal Stream Array – Volume I: NonTechnical Summary of the Environmental Statement.
SABELLA (2013). SABELLA SAS. Consulted on 7 August 2013. http://www.sabella.fr.
SCHOTTEL
(2013).
SCHOTTEL GmbH.
Consulted
on
7
Augstus
http://www.schottel.de/schottel-group/schottel-worldwide/josef-beckerforschungszentrum/schottel-tidal-and-current-energy.
2013.
Scotrenewables (2013). Scotrenewables Tidal Power Ltd. Consulted on 30 October 2013.
http://www.scotrenewables.com.
Sea Generation (Wales) (2013). Sea Generation (Wales) Ltd. Consulted on 12 July 2013.
http://seagenwales.co.uk.
81
IMDC nv
Swanturbines
(2013).
Swanturbines.
http://www.swanturbines.co.uk.
Consulted
on
7
August
2013.
TEL
Consulted
on
7
August
2013.
(2013).
Tidal
Energy
Ltd.
http://www.tidalenergyltd.com.
Tethys (2013). Environmental Impacts Knowledge Management System (KMS). Retrieved
12 July 2013 from http://mhk.pnnl.gov/wiki/index.php/Tethys_Home.
Tidal
Energy (2013). Tidal Energy
http://www.tidalenergy.net.au.
Pty
Ltd.
Consulted
on
30 October 2013.
Tidal Sails (2013). Tidal Sails AS LinkedIn page. Consulted on 17 December 2013.
http://www.linkedin.com/company/1221559?trk=tyah&trkInfo=tas%3Atidal%20sai
ls%2Cidx%3A1-1-1.
TidalStream
(2013).
TidalStream
http://www.tidalstream.co.uk.
Ltd.
Tocardo
(2013).
Tocardo
International
http://www.tocardo.com.
TTC (2013). Tidal Testing Centre
http://tidaltesting.nl.
Consulted
BV.
Den Oever.
on
7
Consulted
Consulted
on
August
2013.
28 October 2013.
on 18 December 2013.
UEK (2013). UEK Corporation. Consulted on 30 October 2013. http://uekus.com.
van Berkel J. (2013). Tidal Conversion Techniques. Pro-Tide work package WP1A2.
Concept version, 9 September 2013, working draft.
Verdant Power (2013). Verdant
http://verdantpower.com.
Power,
VHE (2013).
Vortex
Hydro
Energy.
http://www.vortexhydroenergy.com.
Inc.
Consulted
Consulted
on
on
30 October 2013.
17 December 2013.
VHOCT (2013). Voith Hydro Ocean Current Technologies. Consulted on 7 August 2013.
http://www.voith.com/en/products-services/hydro-power/ocean-energies/tidalcurrent-power-stations--591.html.
Voith (2013). Voith Hydro Ocean Current Technologies brochure. Retrieved 7 August 2013
from
http://www.voith.com/en/products-services/hydro-power/oceanenergies/tidal-current-power-stations--591.html.
VREG (2013). Vlaamse Regulator van de Elektriciteits- en Gasmarkt (Flemish Regulator of
the Electricity and Gas market). Consulted on 8 April 2013. http://www.vreg.be (in
Dutch).
Water
Power & Dam Construction (2003). Consulted on 31 October 2013.
http://www.waterpowermagazine.com/features/featurenorthern-exposure-testingtidal-turbines.
82

Master Class on innovative tidal energy techniques

Transcription

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