Wave Energy News: USA, UK and South Africa
There are multiple ways to tap the energy of the ocean, including its tides, thermal features, and salinity. But wave energy appears to be the most promising and closest to commercial production.
A new report from the Electric Power Research Institute (EPRI) suggests that generation of electricity from wave energy may be economically feasible in the near future. The study was carried out by EPRI in collaboration with the DOE's National Renewable Energy Laboratory (NREL) and energy agencies and utilities from six states.
Conceptual designs for 300,000 megawatt-hour (MWh) plants (nominally 120 MW plants operating at 40% capacity factor) were performed for five sites in the United States: Waimanalo Beach, Oahu, Hawaii; Old Orchard Beach, Cumberland County, Maine; WellFleet, Cape Cod, Massachusetts; Gardiner, Douglas County, Oregon; and Ocean Beach, San Francisco County, California.
The study determined that wave energy conversion may be economically feasible within the territorial waters of the United States as soon as investments are made to enable wave technology to reach a cumulative production volume of 10,000 - 20,000 MW.(For comparison land-based wind turbines currently generate 40,000 MW.)
"Wave energy will first become commercially competitive with land-based wind technology at a cumulative production volume of 10,000 or fewer MW in Hawaii and northern California, about 20,000 MW in Oregon and about 40, 000 MW in Massachusetts," said Roger Bedard, ocean energy project manager. This forecast was based on the output of a 90 MW Pelamis wave energy conversion plant design and application of technology learning curves that will enable cost savings.
The forecast results have convinced the project team of the rationale for investment in wave energy technology research and development, including demonstration projects to prove the feasibility of wave energy conversion technology in actual sea environments.
Bedard explained that there are several compelling arguments for investing in offshore wave energy technology. First, with proper siting, conversion of ocean wave energy to electricity is believed to be one of the most environmentally benign ways to generate electricity. Second, offshore wave energy offers a way to minimize the 'Not in my backyard' (NIMBY) issues that plague many energy infrastructure projects. Wave energy conversion devices have a very low profile and are located far enough away from the shore that they are generally not visible. Third, wave energy is more predictable than solar and wind energy.
A characteristic of wave energy that suggests that it may be one of the lowest cost renewable energy sources is its high power density. Solar and wind energy is concerntrated into ocean waves, making it easier and cheaper to harvest. Experts estimate that 0.2% of the ocean's untapped energy could power the entire world.
Wave power was delivered to the electrical grid for first time in August 2004. The electricity was generated by a full-scale preproduction Pelamis prototype in Orkney, Scotland by Ocean Power Delivery Corporation.
The new EPRI study indicates that a site off the central Oregon coast is probably the best place in the country to establish a United States Ocean Energy Research and Demonstration Center. Electrical engineers at Oregon State University (OSU) have already created three prototypes of devices that could harness wave energy: A permanent magnet linear generator, a permanent magnet rack and pinion gearbox, and a contactless direct drive generator buoy.
Meanwhile in a British company hopes to harness South Africa's wave energy and establish three wavepower farms. The South African government has set targets to introduce renewable energy over the next decade, but there are no commercial renewable energy power plants in the country.
And in more wave energy news, UK Energy Minister Mike O'Brien recently announced a $78 million support scheme for wave power. The new scheme will allocate up to GBP £42 million towards supporting a number of larger scale pre-commercial demonstration wave and tidal farms.
"One of the other extremely promising possibilities with wave energy is the ability to scale these systems either up or down in size, whatever you need to fit the electrical demand," OSU professor of electrical engineering - Annette von Jouanne said. "Small systems could even be used with individual boats at anchor to generate their own electricity."
The development of wave energy right now is probably 15-20 years behind wind power, which is just starting to achieve some optimal production technologies
EPRI Offshore Wave Energy Reports
Eskom Press Release on Wave Energy