#Special mention – Ethereum (ETH)
Ethereum has been making a big song and dance about going green for many years, but there’s been little follow through on all that promise. The cryptocurrency still uses enough energy every year to power a major country and as much electricity per transaction as could power an average U.S. household for a day. Still, Ethereum is more energy efficient than Bitcoin and they’re at least trying to make things better.
The founder of Ethereum has long admitted the wastefulness of the bloated cryptocurrency and in 2014 began a lofty project to overhaul Ethereum’s code with the help of the open-source movement. The plan is to replace the current Proof of Work model with a Proof of Stake mechanism, but progress has been slow. As of 2019, the developers scrapped their original strategy of rebuilding the plane while it is in the air and instead adopted a two-chain approach where Proof of Work and Proof of Stake temporarily run alongside each other. They dubbed this Ethereum 2.0.
In December 2020, Ethereum launched Beacon Chain as the first step in this shift of the network. Under Beacon Chain, Ethereum 2.0 stores and manages the registry of validators and deploys the Proof of Stake consensus mechanism. It is currently running alongside the original chain, however, with full implementation not planned until 2022. This means that the touted one hundredfold reduction in energy per transaction is yet to be realized.