Ocean Thermal Energy Conversion
Excerpts from Energy Broker UK news:
... "Ocean thermal energy conversion (OTEC) uses the temperature difference that exists between deep and shallow waters to run a heat engine. As with any heat engine, the greatest efficiency and power is produced with the largest temperature difference. This temperature difference generally increases with decreasing latitude, i.e. near the equator, in the tropics."... - Wikipedia
"Despite not being a technology that we could use here in the UK, what really caught my attention was the fact that a single 100 Mw floating plant can generate 800 million Kw of electrical energy, without the need of oil, gas or any other fossil fuel. OTEC only needs the temperature difference between the ocean hot surface water and cold deep water."
Watch this video, especially after the 1:45 point:
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