Photo by Steve Jurvetson
Hawaii could be the ideal site for an experimental form of ocean-based renewable energy plants, according to researchers at the University of Hawaii at Manoa. The Ocean Thermal Energy Conversion (OTEC) process utilizes temperate differences in large bodies of water to spin turbines, creating a steady source of renewable energy. The technology has been around for half a century, but the particular temperature differential between the Hawaiian Islands could produce 15% more energy than traditional OTEC plants.
The OTEC process, described in the Journal of Renewable and Sustainable Energy, is fairly simple: a heat engine is placed between warm water gathered from the ocean surface and cold water pumped from deep under the sea. Heat moves from the warm reservoir to the cold one, generating energy that can spin turbines to produce electricity.
A greater temperature differential yields more electricity. And the one degree Celsius differential between the western side of the Hawaiian Islands and the eastern side generates enough extra power to make the OTEC process efficient enough for widespread use in the region — and for other locations with similar temperature differences.