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Hydropower explained Wave power

Waves have a lot of energy

Waves form as wind blows over the surface of open water in oceans and lakes. Ocean waves contain tremendous energy. The theoretical annual energy potential of waves off the coasts of the United States is estimated to be as much as 2.64 trillion kilowatthours, or the equivalent of about 66% of U.S. electricity generation in 2017. The west coasts of the United States and Europe, and the coasts of Japan and New Zealand, have potential sites for harnessing wave energy.

The Pelamis wave power device in use in Portugal

Pelamis wave power device off the coast of Portugal

Source: Marine and Hydrokinetic Technologies Program, U.S. Department of Energy, Energy Efficiency and Renewable Energy (public domain)

CETO underwater wave energy device

CETO underwater wave energy device

Source: Tuscanit, Wikimedia Commons author (GNU free documentation license) (public domain)

Different ways to channel the power of waves

One way to harness wave energy is to bend or focus waves into a narrow channel to increase their size and power and to spin the turbines that generate electricity. Waves can also be channeled into a catch basin or reservoir where the water flows to a turbine at a lower elevation, similar to the way a hydropower dam operates.

Diagram of wave energy site.

Wave energy site

Source: Adapted from National Energy Education Development Project (NEED)

Many other methods of capturing wave energy are under development. These methods include placing devices on or just below the surface of the water and anchoring devices to the ocean floor. The U.S. Department of Energy's Marine and Hydrokinetic Technology Database provides information on marine and hydrokinetic renewable energy, both in the U.S. and around the world.

Last updated: August 28, 2018