A major marine infrastructure project off the coast of Cornwall could help test the efficiency of wave energy devices in the next few years
The South West Regional Development Agency (RDA) is moving ahead with plans for the Wave Hub project, 17 miles offshore England.
Wave Hub is one of a number of projects and facilities that could expand Britain’s exploitation of a plentiful renewable energy source.
According to the U.K.’s Department of Energy and Climate Change (DECC), the British wave and tidal market was worth around GBP 73 million (US$121 million) in 2007/2008. However, wave and tidal power are still in an early stage of development. If properly developed, wave energy could supply around 50 TWh of electricity a year to the U.K., with tidal stream resources adding another 18 TWh per year.
Growth forecasts cited by the government indicate that the wave power sector could grow by over five percent a year until 2015, when it would enter the early mass deployment phase. The cost of testing and demonstrating devices in actual marine conditions has been cited as an obstacle to the industry’s development. The U.K. Government hopes to overcome this with financial support for testing and demonstration facilities.
Wave and tidal lag wind
In the U.K., wave and tidal power solutions have found governmental support, but have taken somewhat of a back seat to offshore wind power proposals. In July, the U.K.’s DECC announced that under the UK Low Carbon Transition Plan, the 2009 budget would include up to GBP 60 million (US$99.5 million) to help accelerate the development and deployment of wave and tidal energy in the country. At the same time, the offshore wind industry in the region was promised up to GBP 120 million (US$198.9 million).
The money for wave and tidal power includes almost GBP 30 million (US$49.7 million) for investment in the Wave Hub project off Cornwall and support for testing facilities at the New and Renewable Energy Centre (NaREC) in Blyth, Northumberland to provide infrastructure for testing marine drive systems and other wave energy device components. GBP 8 million (US$13.2 million) was directed to fund expansion of testing facilities at the European Marine Energy Centre (EMEC) in Orkney, Scotland, while GBP 22 million (US$36.5 million) was earmarked for a Marine Renewable Proving Fund, which would support testing and demonstration of pre-commercial renewable energy devices.
The government has promised around GBP 9.5 million (US$15.7 million) for Wave Hub, plus another GBP 10 million (US$16.6 million) out of GBP 100 million (US$165.8 million of government funding destined for the southwest of England. NaREC will get GBP 10 million (US$16.6 million) to build on and use existing infrastructure.
Another GBP 20 million (US$33.1 million) in funding for Wave Hub has been secured from the European Regional Development Fund Convergance Programme. The South West RDA is investing GBP 12.5 million (US$20.7 million) in the project. Overall, Wave Hub is valued at GBP 42 million (US$69.6 million).
Oyster and others in place for testing
Wave Hub, NaREC and EMEC are all expected to complement each other with the research and development of marine renewable technology. Testing of various wave energy devices has already taken place at NaREC and EMEC.
AquaMarine Power recently completed installation of its Oyster wave energy converter device at EMEC.
The 194-tonne full scale device was lowered onto its seabed subframe and bolted in place. Oyster will next be connected to subsea pipelines which will deliver high pressure fresh water to an onshore turbine ahead of grid connection and sea trials later this year.
Oyster is designed to capture the energy found in near-shore waves up to depths of 10 to 12 meters. Oyster has minimal moving parts, with all electrical components are onshore, making it able to withstand rough seas. The company expects to deliver power to the national grid by the end of 2009.
Bristol-based Tidal Generation Ltd. (TGL) and Irish company OpenHydro have installed and are testing their own tidal power devices at the site. OpenHydro is testing a six-m open center turbine that is installed on the seabed. TGL is developing the 500 kW prototype of what will eventually be a fully-submerged 1 MW turbine.
The Wave Hub socket
Wave Hub itself has been described as an “electrical socket,” installed in around 50 meters (164 feet) of water, 10 nautical miles offshore, and connected to the National Grid by a subsea cable.
Groups of wave energy devices will be connected to Wave Hub, either floating on or just below the surface of the sea. Here, the devices will be tested to determine how well they work in actual maritime conditions and how much power can actually be generated, before the system is placed into full commercial operation.
Four berths will be available at Wave Hub, each covering two square kilometers. Wave Hub will have an initial maximum capacity of 20 MW, though its design allows for it to scale up to 50 MW. The project will be built in the summer of 2010 with the first wave energy devices expected to be deployed in 2011.
The project will work with up to four different technologies at any one time. A one-kilometer by two-kilometer (0.6-mile by 1.2-mile) sea area will be leased to each developer for installation from 2010 onwards. Leases will run for five years and allow each developer to generate a maximum of 4 to 5 MW of power. The Wave Hub will record the strength of the incoming waves and will enter into a power purchase agreement on behalf of all developers using the project.
The infrastructure for Wave Hub involves a substation building at the town of Hayle, Cornwall, adjacent to a connection point to the distribution network. From there, a cable will be taken through a duct beneath the sand dunes and then across the sea bed to an eight-square-kilometer (3.08-sq-mile) area in which the devices will be moored. This area will be indicated with navigational markers.
Ocean Power Technologies (OPT) has become one of the first wave energy companies to commit to development at Wave Hub. OPT will build, install and operate a wave power station comprised of its patented PowerBuoy systems generating up to 5 MW of electricity. Following completion of the Wave Hub infrastructure by the South West RDA, OPT plans to deploy its systems in a phased roll-out. OPT is hoping to bring in commercial partners to invest with OPT in the project.
OPT’s PowerBuoy system uses groups of buoys. The rising and falling action of the waves causes the buoys to move freely up and down. The resultant mechanical stroking is converted via a power take-off to drive an electrical generator. The generated power is transmitted ashore via an underwater power cable. OPT’s latest design, the PB150 PowerBuoy, may also be deployed for testing at EMEC and as part of a wave power project offshore Reedsport, Oregon.
The Wave Hub is also inviting other wave technology developers to submit their own proposals to install wave energy technology at the site.
Subsea cable provider JDR has been awarded a contract to supply subsea power cables for Wave Hub. The scope awarded to JDR includes 25 kilometers (15.5 miles) of 33-kV three-phase power cables, which will provide the link between the Wave Hub and the onshore control room. The wave energy convertors are connected back to the Wave Hub by four additional 300-meter (984-foot) three-phase power cables and dry mate connector sets. All cables include fiber optics and will be subject to rigorous integration testing.
JDR will also supply the Wave Hub assembly, consisting of subsea terminations and a complete subsea protection structure. The package of equipment will be delivered in the second quarter of 2010 from JDR’s new deepwater quayside facility at Hartlepool Dock.
Nick Harrington, Head of Marine Energy at the South West RDA said that recruitment for a Wave Hub general manager would soon begin. The manager would lead operations at the facility.
The South West RDA is hoping that Wave Hub will be a financial boon for the region. An independent economic impact assessment commissioned by the South West RDA calculated that the project could create 1,800 jobs and inject GBP 560 million (US$928.4 million) into the UK economy over 25 years. Almost 1,000 of these jobs and GBP 332 million (US$550.4 million) could be generated in southwest England.