Wind Energy Center

Offshore Wind Energy in Deep Water:The Next GenerationThe Next Generation

New England Conference of Public Utilities Commissioners

James F. Manwell, Prof.Director, Wind Energy Center

Dept of Mechanical and Ind strial EngineeringDept. of Mechanical and Industrial EngineeringUniversity of Massachusetts/Amherst

May 18, 2010

University of Massachusetts

Wind Energy Center

Deep Water Offshore Wind: The VisionDeep Water Offshore Wind: The Vision

Offshore wind farm concept, UMass, 1973

University of MassachusettsSpar buoy concept, UMass, 1973

Wind Energy Center

Potential US Offshore Resource5 - 50 nautical miles

• Shallow water:– ~ 100 GW– (350 TWh)

• Transitional depths:p– ~ 150 GW– (520 TWh)

• Deep water:– ~ 750 GW– (2,600 TWh)

• Total: – ~ 1,000 GW

University of MassachusettsSource: NREL

– (3,500 TWh)

Wind Energy Center

New England Offshore Wind Resourceg

• ExcellentExcellent Resources off New England coast

• Map showsMap shows winds relatively close to shore; even better further out

University of Massachusetts

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Water Depthsp• Much of offshore is too deep for available technology

University of Massachusetts

Wind Energy Center

Floatingg

University of MassachusettsSource: NREL

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Comparison: Land Based Turbinesp

• Capacity– 1.5 – 2.5 MW– (600 - 1000 households)

• Diameter• Diameter– 80 - 130 m (263 - 427 ft)

• Hub height– 60 - 90 m (197 - 295 ft)

• Total height105 155 (345 509 ft)– 105 - 155 m (345 - 509 ft)

• Capacity factor– 20 - 35%

University of MassachusettsBig Horn Wind Farm, Washington. Source: NREL PIX

Wind Energy Center

Shallow Water Turbines• Capacity

– 2 - 5 MW2 - 5 MW– (800 - 2100 households)

• Diameter– 80 - 130 m (263 - 427 ft)

• Hub height60 90 m (197 295 ft)– 60 - 90 m (197 - 295 ft)

• Total height– 105 - 155 m (345 - 509 ft)

• Capacity factor– 35 - 45%

University of Massachusetts

Kentish Flats (UK)

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Shallow Water FoundationsShallow Water Foundations• Water depth

– < 20 m (66 ft)< 20 m (66 ft)

• Monopiles– 4 - 6 m (13 - 20 ft) diameter– 20+ m (66 ft +) deep

• Gravity caisson17 m (56 ft) diameter– 17 m (56 ft) diameter

– 1,800 metric tonnes (~ 2000 tons,~11 diesel locomotives)

University of Massachusetts

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Shallow Water Technologygy• Installation

– Jack-up barge with craneJack-up barge with crane

• Economics– $3 - $5 million / MW

University of MassachusettsLife cycle cost of energy

Wind Energy CenterTransitional Depths30 60 m (100 200 ft)30 - 60 m (100 - 200 ft)

University of MassachusettsSource: NREL

Wind Energy Center 12

Transitional DepthsExample: Beatrice demonstration project

• Northeastern Scotland, T li ETalisman Energy

• Two 5 MW turbines• 45 m (148 ft) deep• 45 m (148 ft) deep• $50 million ($5 million / MW)

www.beatricewind.co.uk

University of Massachusetts

Wind Energy Center

Deep Waterp• Advantages

– Potentially much greater wind resource– Much greater total energy potential– Reduced visual impact – “over the horizon”– Less shipping traffic; potentially out of migration routes

• DisadvantagesDisadvantages– More expensive components, installation, maintenance– R&D needed for floating supportsg pp– Greater cost risk and lack of support infrastructure– Harsh environment—people and equipment

University of Massachusetts

Wind Energy Center

Floating Platform Optionsg p

Dutchtri-floater Barge Spar Mono-hull

TLP

Concept Marine

Associates C t TLP

SWAYTLP Concrete TLP

University of MassachusettsSource: NREL

Wind Energy CenterCurrent Work in Deep Water R&D

• Turbine prototypes

• Technology transfer from petroleum industryfrom petroleum industry

• Developing engineering modeling tools

• Developing systems to increase accessibility

• Detailed quantification of the wind resource and ocean environment

• More thorough understanding of the deep water environment and marine ecology

University of Massachusetts

gy

Wind Energy Center

Deep Water Wind R&D in Europep p• Spar buoy designs: Hywind (Siemens and Statoil)

Prototype

University of MassachusettsConcept

Wind Energy Center

Deep Water Wind R&D in Europep p• Tension leg platform (TLP): BlueH

University of Massachusetts

Wind Energy Center

Turbine Design Considerationsg•Wind

•Waves•Waves

•Tides

I•Ice

•Currents

•Soil

•Materials

•Anchoring

• Marine life

University of Massachusetts

a ine life

•More!

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Example: Storm wavesp

• Design must anticipate forces due to waves!

Texas Tower 4, off NJ, destroyed Breaking waves on structure

University of Massachusetts

, , yin storm, 1961similar to offshore wind turbine;

forces can be very large!

Wind Energy Center

Example: Turbine on Spar Buoyp p y

• 5 MW turbine (like Beatrice) on spar buoy( ) p y• Turbine weight: ~700 mt ( ~ 4 locomotives)• Spar: 120 m draft; weight: 7500 mt (~ 42

locomotives)• Total weight: 8,200 mt (~2.3 x Liberty Ship)

University of Massachusettshttp://www.dvrbs.com/monuments/camden/CamdenMMliberty.jpg

Wind Energy Center

Electrical Transmission• AC submarine cables used at present

C d id i f l di• HVDC under consideration for longer distances• Interconnection on land significant issue• “Supergrid” under consideration in Europe

University of Massachusetts

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Infrastructure• Vessels and ports will be critical!

High speed service vessel Floating crane

University of Massachusetts

Wind Energy Center

Why Did Europe Move Offshore?y pA variety factors created an attractive environment in Europe for initiating offshore wind development, including:

• Limitations on landG l f bl• Goals for renewable energy

• Large expanses of relatively shallow oceanE cellent ind reso rces offshore• Excellent wind resources offshore

• Available maritime industries and capabilities• Policy including “feed in tariffs”• Policy, including feed-in tariffs • Opportunity for technical superiority and industry development

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Considerations for the US

• Policy, planning, incentives

• Infrastructure

• Supply chain• Supply chain

• Environmental issues

• Research and development

• EducationEducation

• Experience

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Wind Energy Center

Summaryy

• There is tremendous offshore wind energy potential gy pin New England.

• Shallow water technologies available, but still g ,maturing

• Transition and deeper water technologies are at the p gR&D level.

• Major offshore wind activities in Europe will spur jo o s o e w d c v es u ope w spudevelopment here

• Deep water offshore wind will eventually come to

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eep wate o s o e w d w eve tua y co e toNew England