Ocean Thermal Energy Conversion

It is estimated that the amount of solar energy absorbed by the oceans per year is 4,000 times the amount currently consumed by humans.

Proposals to turn this energy into electricy date back to Jules Verne's "Twenty Thousand Leagues Under the Sea" published in 1870. Eleven years later French physicist Jaques-Arsène d'Arsonval proposed using the relatively warm surface water of the tropical oceans to vaporize pressurized ammonia and use the resulting vapor to drive a turbine-generator. D'Arsonval's proposal was finally demonstrated in 1979.

Now several islands are considering plans to build
Ocean Thermal Energy Conversion (OTEC) plants, including Saipan, Taiwan, and Hawaii. Last Friday
Ocean Engineering & Energy Systems announced plans to build the world's two largest power plants making electricity from sea-water heat. In addition, the Natural Energy Laboratory of Hawaii will build a 1-megawatt OTEC power plant.

An additional benefit of OTEC power is the production of fresh water as a by-product, something that is increasingly in short supply in many parts of the world.