About freakin time. Using natural resources to do imaginary things like this is beyond disgusting. Bitcoin may have some interesting technology in it, but the idea that we have to run computers and generate NOTHING OF WORTH to utilize it is insane.
Financial infrastructure isn't nothing of worth, however since Bitcoin still mostly gets converted to and from fiat currency, it doesn't provide a huge amount of worth on its own outside of things like remission. There are faster, more easily scalable cryptocurrencies for payments and settlement, though, and there are other cryptocurrencies and blockchains that do "real" work or have the potential to do so, like Deepbrain Chain, RNDR, doc.ai, Curecoin, Primecoin, etc.
Ethereum is moving to Proof-of-Stake (was always part of the original plan, just hasn't finished stage of development just yet) and there are other cryptocurrencies using PoS, hybrid PoS, or other much lower power usage algorithms. PoW was always an easier solution to preventing attacks to the network because of the "nothing at stake" problem, and we've known for years that global electricity usage for bitcoin mining would increase with difficulty.
But it's not like traditional financial systems don't use any power, either, and all the servers in the world aren't exactly running 100% green. I agree, though, if mining does move away from electricity heavy PoW and mining farms use more renewable energy sources like solar it wouldn't be a bad thing. In any case, I don't expect Bitcoin to be the number one cryptocurrency for much longer, but it may take a while for mining to subside to a much lower amount of electricity use worldwide.