Maybe it's a silly question but I don't know the answer and I'd love some pointers/links.
How is Solana so much less energy than eth2? and how is that less than eth1, and that less than btc? I'm guessing it's not just "bad coding" or "it's electron so it's feeding on ram" or something. or is it?
Bitcoin and Ethereum in its current implementation uses Proof of Work, which is a very energy intensive process, and the energy used helps protect the network by ensuring its very costly for bad actors to attack the network.
For newer blockchains like Cosmos, which uses Proof of Stake and Solana which uses Proof of History, they have other mechanisms to protect from a 51% attack, and so does not need the validator/miners to consume energy like the Proof of Work consensus systems.
Proof of Stake protocols typically use variants of BFT consensus, which support only up to 33% malicious voting power. So no, they do not protect against 51% attacks like Nakamoto consensus protocols do.
Solana is pretty centralized, it was designed to be an efficient version of a blockchain. So, it works more like a traditionally engineered HA service would, but with some blockchain bits attached. This makes it fast and cheap, but it isn’t very decentralized as a result.
How is Solana so much less energy than eth2? and how is that less than eth1, and that less than btc? I'm guessing it's not just "bad coding" or "it's electron so it's feeding on ram" or something. or is it?