The Merge is around the corner. The Ethereum network is expected to experience a significant shift after the most anticipated upgrade. Since its launch in 2015, the smart contract compatible network has proven its relevance and utilities. By that time, blockchain was introduced and used for transactions such as Bitcoin, Litecoin, etc., Etherum brought more practical use of blockchain.
Ethereum network brought smart contracts making the digital ledger capable and far more practical. It made blockchain more than a transactions centric technology to act as a platform allowing development of decentralized applications.
Now with the transition from a heavy energy intensive consensus mechanism of proof-of-work to proof-of-stakes, the Ethereum network is all set to take another leap. The reason the transition is a big deal is due to energy consumption by the PoW chain.
Several reports estimated the total energy consumption of Ethereum network transaction for the overall year is upto 113 terawatt-hours. This much energy is equivalent to be consumed by the Netherlands within a similar timeframe. To get more close vision, look at the energy spent to validate just one ETH transaction which would be sufficient to power a US household upto one week.
However, after the transaction following the Merge upgrade, the energy consumption of the entire network is expected to drop by almost 99.5%. This is a massive drop in energy consumption and is sufficient to tag Ethereum comparatively less energy consuming blockchain.
The network already had the awareness towards PoS, as it has mentioned the same in its white paper. Yet chose to go with PoW with the intention to shift in future to PoS. This initiative for the upgrade started in the year 2020, with the formation of Beacon Chain. The chain is considered as a consensus chain other than the main execution chain —Ethereum Mainnet. The Merge is broadly meant to combine both these chains.
Source: https://www.thecoinrepublic.com/2022/09/14/the-merge-expected-to-reduce-ethereums-energy-consumption-by-99-5/