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10 surprisingly easy sources of alternative energy

By: Bryan Nelson on Nov. 30, 2009, 11:27 a.m.
An ocean rig cloaked by golden and orange clouds at sunset

Photo: Glenn Beltz/Flickr [CC by 2.0]

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Ocean Thermal Energy Conversion (OTEC)

Ocean thermal energy conversion, or OTEC for short, is a hydro energy conversion system that uses the tempurature difference between deep and shallow waters to power a heat engine. This energy could be tapped by building platforms or barges out at sea, taking advantage of thermal layers found between the ocean depths.