Algorand has been Proof of Stake for years (2019 MainNet launch) and it's actually carbon-negative [1]. It's a shame more people don't know about it. Its founder is a Turing-award-winning MIT professor (Silvio Micali) who solved the blockchain trilemma [2] with the Pure Proof of Stake consensus algorithm. The tech is leaps and bounds ahead of other cryptos.
[1]: https://www.algorand.com/resources/news/carbon_negative_anno...
[2]: https://www.algorand.com/resources/blog/silvio-micali-lex-fr...