Ocean Power Fights Current Thinking
Ocean waves provide a predictable source of energy that is easily tapped, and will likely have minimal impact on the environment, but the U.S. government is not pursuing this renewable resource.
Recent advancements in the technology indicate that with a relatively small investment from the government, wave energy could soon compete with other renewable sources.
Wave energy systems place objects on the water’s surface that generate energy by rising and falling with the waves. The wave energy in turn moves a buoy or cylinder up and down, which turns a generator that sends the electricity through an undersea cable to a power station on the shore.
Several companies – Ocean Power Delivery, AquaEnergy Group and Ocean Power Technology – have developed prototype wave energy conversion systems that the companies say are ready to be deployed along United States coastlines.
The potential energy to be captured from ocean waves could surpass the other forms of renewable energy such as solar, wind, or hydropower, according to a recent study by the Electric Power Research Institute (EPRI), a research group funded by hundreds of utilities.
According to a report released in January, 2005, the total wave power along the coastlines of the U.S. is approximately 2,100 terrawatt hours per year, nearly as much as all of the electricity produced by coal and roughly 10 times the total energy produced by all of the country’s hydroelectric plants.
Wave energy systems can capture the same amount of energy using smaller and less expensive equipment than wind or solar systems, according to Roger Bedard of EPRI, who authored the study.
Wave energy “is among the most environmentally benign technologies,” and is less visible than off shore wind farms, according to Bedard. He says wave energy conversion devices have a smaller footprint than offshore wind farms and interfere less with marine life movements.
Bedard says that wave energy systems requires smaller investments than offshore wind energy systems because the equipment is much lighter, but the private sector has been wary to invest because the expense for setting up demonstrations is high, and obtaining federal permits can take many years.
Instead, Bedard says the federal government should step in with funding to help the technology succeed.
“Very simply, new energy sources have always been funded by the federal government,” Bedard says. However, “(t)he Department of Energy does not have an ocean energy program.”.
The Department of Energy had a program for ocean energy, but it was discontinued, according to spokesman Tom Welch.
Several wave energy systems are currently being tested in the United Kingdom, a country which according to Bedard “wants to be the world leader.”
Ocean Power Delivery’s Pelamis system, a series of steel cylinders, began riding the waves off the coast of Scotland in August of 2004 and is sending sufficient electricity to the grid to power 500 households annually.
The 750-kilowatt wave energy conversion devices resemble metal sausage links that are connected by hydraulic pumps that pressurize oil to turn a generator and produce electricity, according Ocean Power Delivery. The devices are connected to a junction box on the seabed and feed electricity through a single cable to the shore.
Ocean Power Technologies (OPT) of Pennington, NJ, is currently building a one-megawatt wave energy system off the coast of Hawaii for the U.S. Navy, according to company founder and CEO George Taylor.
The OPT’s PowerBuoy systems converts the up and down motion of the ocean, to electricity and feeds the energy via an undersea cable into the power grid. Taylor says the project will begin to generate electricity this year and will be completed by 2006.
The cost of the technology will go down as larger systems are developed, according to Taylor. The current technology can generate electricity at a cost of between 7 to 10 cents per kilowatt hour, depending on the quality of the waves, according to Taylor.
Mass producing the devices will drive down the cost over time, making them competitive with both on- and offshore windfarms, Taylor says, and to that end, the company is planning test the technology off the coasts of New Jersey and Spain.
“Within five years we will be able to compete with fossil fuels by delivering energy at three to four cents per kilowatt hour,” says Taylor.
AquaEnergy Group is trying to obtain the necessary federal permits to test its AquaBuoy technology in the Makah Bay of Washington state, according to Alla Weinstein, the president and CEO of the Mercer Island, WA, company.
Weinstein says the AquaBuoy uses a hose pump that expands and contracts as the waves go up and down, creating water pressure that is used to produce electricity.
“We could be in the water in less than 12 months after the permit is approved,” says Weinstein. Her company, which this month received a $1 million investment from Irish renewable energy company Finavera, is seeking $3 million in federal funding to complete the demonstration project.
However, the comprehensive energy bill that has been stalled in Congress for several years does not include ocean energy among its list of renewable resource eligible for tax credits, Weinstein says. The Bush administration has been unsuccessful in passing the energy policy because it includes a controversial provision that opens the Alaska’s Arctic National Wildlife Refuge to oil drilling.
Across the Atlantic, however, the British parliament is actively supporting wave energy through funding programs and a new testing facility. The government established the European Marine Energy Centre in 2004 to test emerging technologies being developed by private companies .
“The U.K. has a national renewable energy strategy that is driven right from the top,” says Mike Rosenfeld, the vice consul of the British Consulate-General in Los Angeles.
Rosenfeld recently made a trip to the Northwest U.S. where he met with several U.S. wave energy companies to encourage them to test their technology at EMEC.
“The idea is that a U.S. marine energy developers have a good opportunity to tap into UK policies and funding mechanisms for testing and development, after it is proven, the technology can be brought back to the U.S.,” Rosenfeld says.
In addition to having greater energy potential than other renewable sources, ocean energy is viewed as more aesthetically pleasing. Wave energy systems “have less visual impact” than offshore wind farms because they are partially submerged, according to Cliff Goudey, director of Massachusetts Institute of Technology’s Center for Fisheries Engineering Research.
One challenge is that wave energy systems must be engineered to tolerate the sometimes volatile conditions of the ocean, Goudey says. “You need to have areas where the average waves are not that different from the extreme waves, and the devices have to design to withstand a storm, but also be efficient with average current,” he says.
If testing programs succeed, ocean energy could become cost-competitive with wind energy in as little as four years, according to EPRI’s Bedard. However, Bedard is doubtful that the current administration will have a sea change of opinion on ocean energy. “The administration is basically a coal and oil administration,” Bedard says.
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