Ocean Thermal Energy Corporation (OTE Corporation) from Lancaster, Pennsylvania (US) has won a contract to design its first two commercial plants that generate electricity from temperature differences in ocean water.
According to a report in a Lancaster newspaper, OTE Corporation has signed a memorandum of understanding (MOU) with Bahamas Electricity Corp., which provides electricity to 85 percent of the country’s electricity consumers, to design and construct two of OTE Corporation’s unique plants. The plants would be owned and operated by OTE Corporation and would cost about $100 million to develop. They would have a nameplate capacity of between five and 10 megawatts.
The agreement represents a milestone in this novel technology, which comprises “a base-load renewable energy production process particularly suited for tropical zones”. The technology, which OTE Corporation describes as “proven”, having demonstrated the technical viability of a 210 kW pilot plant at the Natural Energy Laboratory of Hawaii, uses the ocean’s temperature differential between the warm surface water and the cold deep water to generate both electricity and potable water.
Most of the power produced at the new facilities on the Bahamas would be used by the local utility to meet 9 percent of its needs, although some would be siphoned off by a desalination plant to provide water and drinking and aquaculture. The potable water would be sold to the Bahamas’ water company.
What is ocean thermal energy conversion? According to the U.S. Department of Energy:
Ocean Thermal Energy Conversion (OTEC) uses the heat energy stored in the Earth’s oceans to generate electricity.
OTEC works best when the temperature difference between the warmer, top layer of the ocean and the colder, deep ocean water is about 20°C (36°F). These conditions exist in tropical coastal areas, roughly between the Tropic of Capricorn and the Tropic of Cancer. To bring the cold water to the surface, OTEC plants require an expensive, large diameter intake pipe, which is submerged a mile or more into the ocean’s depths.
Some energy experts believe that if it could become cost-competitive with conventional power technologies, OTEC could produce billions of watts of electrical power.
For more information on the process see this page from the U.S. Department of Energy and this one from the U.S. National Renewable Energy Laboratory.
Previously on Green Antilles: Wave energy for The Bahamas.
[Image via: renewableenergymagazine.com]