Ethereum client Nethermind tweeted that the Sepolia Beacon Chain is deployed and Ethereum's 2nd public testnet chain merge is just around the corner.
Upon merging with its dedicated Beacon Chain, the Sepolia testnet will reach a consensus using Proof-of-Stake (PoS) rather than Proof-of-Work (PoW) to perform test trials. The exact date of the Sepolia merge, however, has not been revealed.
Testnet merges enable developers using the Ethereum network to understand what they can expect when the actual merge takes place. Just like on the testnets, the Ethereum mainnet merge will see the entire network transition to PoS consensus and should reduce the energy consumption of Ethereum by 99.9%.
Back in April, Core Ethereum developer Tim Beiko tweeted that the Ropsten testnet would be phased out over time and replaced by Sepolia. Therefore, projects running apps on Ropsten should move over to Sepolia to avoid complications.
Public testnets like Sepolia and Ropsten are designed to replicate the operating conditions of their respective mainnets without affecting the live mainnet.