A major upgrade to the Ethereum blockchain that started in late 2020. Dubbed "Serenity," Ethereum 2.0 (Eth2) is designed to be more scalable (more transactions per second), more secure and more environmentally conscious. Eth2 uses the Casper proof-of-stake (PoS) consensus method of mining instead of proof-of-work (PoW), which has been used by both Ethereum and Bitcoin since their inception. Proof-of-work uses a tremendous amount of electricity, but Casper should cut that by 98%.
Locking Up (Staking) Ether to Participate
Any entity that wants to be an Ethereum 2.0 miner, known as a "validating node," must lock up 32 ether. This can be a single user or a staking pool that combines the ether from a group of people.
The Upgrade Path
December 2020 was the implementation of the "Beacon Chain" using the Casper consensus method. In October 2021, enhancements were added with the Altair upgrade. Expected in 2022, the original Ethereum network and Beacon will merge, and "stakeholders" will begin adding blocks. Eventually, up to 64 additional blockchains, known as "shards," will be created, and the Beacon blockchain will manage them. In time, greater node anonymity and more randomness in selecting the node that adds the block to the blockchain are expected. See Ethereum
and proof-of-work algorithm