Wave and tidal power could provide up to a third of the electricity in the United States by 2030, according to two new reports released on Jan. 18 by the Dept. of Energy. According to the studies, wave and tidal power could generate about 1,420 terawatt hours, or TWh, of electricity per year. The U.S. uses 4,000 TWh each year.
"Although not all of the resource potential identified in these assessments can realistically be developed, the results still represent major opportunities for new water power development in the United States," said a DOE press release. About 6% of the nation's energy comes from conventional hydropower resources, DOE said.
The studies show that while West Coast states have a high potential for wave energy development—that is, 590 TWh—the East Coast could produce up to 240 TWh of electricity a year. Previous studies did not identify the East Coast as a potential source for wave power.
Alaska's coast has the greatest potential, according to the study by the Electric Power Research Institute of Palo, Alto, Calif. EPRI conducted a similar study in 2004, but the updated, DOE-funded study indicated more wave power than had been expected.
The studies themselves are a big step toward commercializing wave and tidal power, says Sean O'Neill, president of the industry group Ocean Renewable Energy Coalition. "They are tremendous," he said of the studies. "DOE's investment in these studies, as well as the corresponding results, is a testament to the importance of our unique opportunity to pursue a diverse energy portfolio that includes wave and tidal energy in an effort to secure our energy supply, create jobs and lower greenhouse-gas emissions."
Large tidal, hydrokinetic or wave energy projects have been slow to get off the ground partly because wave and hydro power were not even in the federal definition of renewable energy until 2005, O'Neill says. In other regions of the world, wave and tidal power have had a head start. On Jan. 17, Alstom Renewables and Scotland-based SSE Renewables signed an agreement to develop the world's largest wave project—up to 200 MW—off the coast of Scotland.
Another obstacle for U.S. developers is the lengthy permitting process for hydropower, which is geared to massive hydroelectric dams on interior rivers.
"We need accelerated decision-making in permitting and regulation. We need investment incentives. Marine and hydrokinetic power get half" of the amount allocated to other renewables in the nation's production tax credit, and they don't get to accelerate the depreciation of assets as other renewable projects do under tax law, O'Neill says.
In one example, New York City-based Verdant Power put in its prototype a decade ago for a turbine to capture tidal power in that city's East River. The company expects its first pilot commercial license from the Federal Energy Regulatory Commission early this year.