"140-year-old ocean heat tech could supply islands with limitless energy" if there's a 20° C thermal gradient; because the ocean is a big thermal battery that s

"140-year-old ocean heat tech could supply islands with limitless energy" if there's a 20° C thermal gradient; because the ocean is a big thermal battery that stores infrared from the sun especially at the surface of the water: https://news.ycombinator.com/item?id=38222695 https://news.ycombinator.com/item?id=38222695