An energy responsible solution.
I propose a means of calculating all the POW/hashes/BlockChainGubbins/CryptoDoohickies you want, all while reducing your impact on the electricity supply, lowering the impact on the climate, & proving that you're serious about helping to save Humanity.
A device that can be used to do all the calculations you want, uses no grid power, & contributes nothing to worsening the problems.
It will have the side benefit of removing the miner-hoarding-kit issue so that prices for all such hardware can return to a sane level.
Best of all, the threat of a chip shortage, supply chain hiccoughs, or other artificial restrictions on the supply can't even begin to affect the market for the devices I propose.
In fact, if governments around the world make it law that all mining must be done on such devices from now on, then enforces that law with extreme prejudice, it would go a very long way to hitting the brakes on the current rate of climate change.
The device I propose is, of course, the Abacus.
A wooden frame, some string, some rocks with holes drilled through them, and you've got yourself a device by which to calculate all the CryptoCoins you want!
/Sarcasm.