Getting energy from the ocean seems like a good idea. Oceans cover nearly ¾ of the planet, so they represent a gigantic energy resource. Most schemes for extracting energy from oceans center around moving water: either waves or tides. But there is another energy source in the sea that is starting to get some serious attention: ocean thermal energy conversion or “OTEC.”
OTEC makes use of the temperature difference between warm surface water, such as found in the tropics, and cooler water deeper down. Such a temperature difference can be used to drive a heat engine to generate electricity. This technique is particularly attractive for island and coastal communities where energy transportation costs typically make other sources of power very expensive. OTEC power also has the advantage that it is available around the clock.
OTEC has been explored for decades, but it’s never been utilized on a commercial scale. Recently aerospace giant Lockheed Martin announced a joint agreement with Beijing-based Reignwood Group to build an OTEC pilot power plant off the coast of southern China. The 10 megawatt plant will be the largest ever built and will supply 100% of the power needed by a new green resort to be built by Reignwood.
Lockheed sees the potential for OTEC plants as large as 100 megawatts, big enough to power a small city. OTEC technology can also supply clean drinking water and even hydrogen fuel. While not practical everywhere, OTEC is yet another renewable energy source that belongs in our energy bag of tricks.
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Lockheed Martin and Reignwood Group to Develop Ocean Thermal Energy Conversion Power Plant
Photo, taken on August 13, 2012, courtesy of Heather Paul via Flickr.
Earth Wise is a production of WAMC Northeast Public Radio. Support for Earth Wise comes from the Cary Institute of Ecosystem Studies in Millbrook, NY, with partial support from the Field Day Foundation.