I've pointed this out in the past--there are only certain places, even in the ocean, where sea solar power works. You need depths in the 3,000 foot range to make it practical.

If we're talking about Hawaii, OTEC probably rocks. If we're talking about Denver, or even coastal cities near major continental shelves, not so much.

You cannot run our civilization on wind, solar, tidal, or other alternative power sources. You can use alterative sources to augment the power supply, and take loads off of normal power sources in peak demand, so alternative power isn't useless by any means, but you can't do it all. People simply do not want to face that.

Nor can you destroy our standards of living down to the point where we could get by on only alternative energy. Well, maybe you could, but I'd hate to live there.