If a solar company made a lot of profit and used it to buy-back and burn (remove from circulation) tokens on a blockchain at regular monthly intervals and this rule was part of their memorandum of incorporation and they were legally committed to continue with this approach then of course I would want to own some of those tokens because I know I could sell my tokens back to them at any time on the open market. Clearly they have value so long as there is an economic activity underlying them.

And BTW, not all blockchains use a lot of electricity. Some (PoS) use very little.