Thermal Variances in Oceans Yield Renewable Energy

For years the world's oceans have been looked at for sources of renewable energy, primarily in the form of wave, tidal and current energy. But a different technology known as Ocean Thermal Energy Conversion (OTEC) could potentially generate a significant amount of electricity.

OTEC relies on the temperature difference between water on the surface and at the ocean's depths. The technique uses heat from warm surface water to boil a liquid with a low boiling point, creating steam that spins a turbine that generates electricity. Cold water pumped from the depths via large pipes then cools the steam, condensing it back into a liquid that can be reused. The idea isn't new-it was first proposed by a French physicist in 1881-but interest in developing the technology has recently been revived.

Researchers hope that further development of the technology could result in power plants as large as 500 megawatts. Stresses on the submerged pipes from waves and underwater currents have caused problems in creating plants on such a large scale. To address this, the Department of Energy recently awarded $600,000 to Lockheed Martin to develop new cold-water pipes.

You can read more about OTEC here.