How green is my bitcoin?

Green bitcoin has been proposed as a way to counter the excessive energy consumption and CO2 emissions of cryptocurrencies. However, Martin C.W. Walker writes that the whole idea that you can create a green type of bitcoin that would work alongside non-green ones is hard to maintain. That would mean ignoring the way the cryptocurrency “mining” system works. He finds a potential solution in a joke white paper by an author purporting to be Natoshi Sakamoto’s wife: a single ordinary server to process the same volume of transactions as the entire bitcoin network.