How about not using one of the most in-demand resources on the planet for the foreseeable future?

Proof of Stake algorithms hash the work what? Once? There’s no need to waste all that “computation” like Proof of Work does. Do I think Proof of Stake is the end all, be all? No, it’s probably not, but as far as efficiency goes, it’s a win. 

The problem with all the algos we have is, no matter resource you tie it to – mining equipment, electricity, staked coins, etc – at some point you’re either destroying the places and things we need or just slowly building monopolies that will eventually usurp the federated nature of these networks through secret dealings and mergers.

Even if we use it build out renewables, that’s that much less renewable energy that is locked up AND getting converted directly to waste heat cooking the planet and us with it.