Mining uses a miniscule amount of energy compared to all the wasteful use of electricity in the United States alone.

How come the electricity consumption per capita is more than 2.5* that of Germany?

If everyone of the 318m US citizens would reduce power consumption by only 10% (easily achieved by switching lightbulbs...), it would save 25 700 MW of generation capacity alone.

You can do all the bitcoin mining of your hearts´content with that, and then some.