A very extraordinary but old concept that can be used to power the world. However, a new technique called ocean thermal energy conversion will be integrated into the system. From Inhabitat:

Their goal is to build a network of “energy islands”: floating hexagonal-shaped platforms of reinforced concrete and corrosion-resistant metals that would generate electritict via wind, wave, and solar in addition to having an OTEC plant. It’s estimated that each island complex could produce about 250MW, and that 50,000 “energy islands” could meet the world’s energy requirements (as well as provide two tons of fresh water per person per day for the entire world population — desalinated water is one byproduct of the OTEC process). OTEC plants work best when there’s a temperature difference of 20°C between water at the surface and the water below, making tropical and sub-tropical seas the best candidates for energy islands.

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