The U.S. Department of Energy (DOE) has released two nationwide resource assessments showing that waves and tidal currents off the West and East coasts could generate up to one-third of the nation’s electricity usage per year. The two reports, “Mapping and Assessment of the United States Ocean Wave Energy Resource” and “Assessment of Energy Production Potential from Tidal Streams in the United States,” calculate the maximum kinetic energy available from waves and tides off both U.S. coasts that could be used for future energy production. The analyses show that water power, including conventional hydropower and wave, tidal, and other water power resources, can potentially provide 15% of the nation’s electricity by 2030, or 1420 TWh. The US uses about 4000 TWh of electricity per year, according to the DOE. The West Coast, including Alaska and Hawaii, has especially high potential for wave energy development, while significant opportunities for wave energy also exist along the East Coast. Additionally, parts of both the West and East Coasts have strong tides that could be tapped to produce energy. Earlier this year, DOE announced the availability of its national tidal resource database, which maps the maximum theoretically available energy in the nation’s tidal streams. This database contributed to the “Assessment of Energy Production Potential from Tidal Streams in the United States” report, prepared by Georgia Tech. The wave energy assessment report, titled “Mapping and Assessment of the United States Ocean Wave Energy Resource,” was prepared by the Electric Power Research Institute (EPRI), with support and data validation from researchers at Virginia Tech and DOE’s National Renewable Energy Laboratory (NREL). The report describes the methods used to produce geospatial data and to map the average annual and monthly significant wave height, wave energy period, mean direction, and wave power density in the coastal United States.