Millions of American homes could soon be powered by the ocean’s waves, tides, and currents.

An estimated 2.64 trillion kilowatt hours could be produced annually from wave energy alone, which is equivalent to 64 percent of the electricity generated across the nation in 2018. Waves, tides, and currents could generate as much as 90 gigawatts of power, according to the U.S. Department of Energy (DOE).

PNNL researchers are working to understand and predict marine energy, particularly wave and tidal resources, to maximize this power potential and to give industry confidence in the reliability of marine energy.

What’s in a wave and tide

Researchers conduct marine energy resource characterization work from the Marine and Coastal Research Laboratory (MCRL), previously known as the Marine Sciences Laboratory, at PNNL-Sequim, in support of DOE’s Water Power Technologies Office. MCRL is DOE’s only marine energy research laboratory. MCRL scientists are studying what it takes to develop and deploy marine energy resources by using theoretical analysis, numerical modeling, and field-measurement approaches.

PNNL researchers use wave spectral modeling capabilities to simulate, classify, and predict resources for wave energy in U.S. coastal regions. Wave spectral models use meteorological and oceanographic data to predict the sea states under various conditions, especially large waves induced by extreme storms. Meteorological and oceanographic data include sea surface winds, tides, and ocean currents. Long-term wave modeling allows researchers to evaluate the seasonal, interannual, and decadal variabilities of wave climate.

PNNL researchers have developed an advanced turbine farm model to simulate tidal energy in energetic tidal current systems. The tidal-turbine modeling tool enables the ability to accurately estimate the maximum extractable tidal energy in specific tidal sites, assist with optimal site selection, and understand the potential environmental impacts of tidal energy extraction. Coupled with coastal hydrodynamic and transport simulations, the tidal turbine model can be used to evaluate the environmental interaction between tidal energy extraction and marine ecosystems, such as impacts on water quality, fish migration, and sediment erosion and transport. 

PNNL’s wave and tidal resource characterization and assessments inform designs for wave energy and tidal current converters, reduce financial risks, and guide device siting to meet energy production goals and commercial development at specific sites. Additionally, researchers are identifying and mitigating environmental concerns arising from technologies that harness marine energy.