I found this very interesting. Such a power source could provide power to an underwater complex, labs or city as well.
SOLO-TREC Deployed off the Coast Of Hawaii NASA/JPL/U.S. Navy/Scripps Institution of Oceanography
Navy Submarine Runs Eternally on Thermal Power from Ocean Currents | Popular ScienceA Navy-funded thermal engine bobbing off the coast of Hawaii is accomplishing a rare feat -- it produces more energy than it consumes.
In search of the real truth.