EPRI Ocean Energy Program
EPRI Wave Energy Conversion (WEC) Project
EPRI Tidal In Stream Energy Conversion (TISEC) Project
EPRI River In Stream Energy Conversion (RISEC) Project
Welcome to the EPRI Ocean Energy Web Page!
What is ocean energy?
"Ocean energy" is a term used to describe all forms of renewable energy derived from the sea including wave energy, tidal energy, river current, ocean current energy, offshore wind, salinity gradient energy and ocean thermal gradient energy.
For more information, please contact
- Wave energy is the capacity of the waves for doing work. Ocean waves are generated by the influence of the wind on the ocean surface first causing ripples. As the wind continues to blow, the ripples become chop, fully developed seas and finally swells. In deep water, the energy in waves can travel for thousands of miles until that energy is finally dissipated on distant shores.
- Tidal in stream energy occurs due to the moving mass of water with speed and direction as caused by the gravitational forces of the sun and the moon, and centrifugal and inertial forces on the earth's waters. Due to its proximity to the earth, the moon exerts roughly twice the tide raising force of the sun. The gravitational forces of the sun and moon and the centrifugal/inertial forces caused by the rotation of the earth around the center of mass of the earth-moon system create two "bulges" in the earth's oceans: one closest to the moon, and the other on the opposite side of the globe.
- River in stream energy occurs to the hydrokinetic energy of the moving river water. A tidal signature can be seen in rivers up to a hundred miles or so from where the river empties into the ocean. In these cases, it is not important whether the site is called a tidal site or a river site. The velocity of the river current is a function of the slope of the reach and the effect of gravity and the roughness of the riverbed and the effect of frictional forces slowing the current.