The Merge refers to Ethereum’s landmark transition from Proof of Work (PoW) to Proof of Stake (PoS) consensus, completed on September 15, 2022 at 6:42:42 UTC (at terminal total difficulty 58750000000000000000000). It was the result of years of research and development, merging the original Ethereum execution layer with the Beacon Chain — Ethereum’s PoS coordination chain that had been running in parallel since December 2020. The Merge effectively ended Ethereum mining, reduced energy usage by ~99.95%, and cut net ETH issuance by approximately 90% — combining with EIP-1559’s burn to make ETH net deflationary.
Background: The Beacon Chain
Ethereum’s path to PoS required running a separate consensus chain in parallel before fully merging:
- December 1, 2020: Beacon Chain launched — a new PoS chain running alongside the original PoW Ethereum chain (the “mainnet”)
- The Beacon Chain handled consensus (validator coordination) but had no transaction execution capability
- Over $30 billion in ETH was progressively staked into the Beacon Chain deposit contract before the Merge
- September 15, 2022: The execution layer of Ethereum (transaction processing) merged with the Beacon Chain — PoW mining stopped instantly at the final PoS block
What Changed
| Before The Merge | After The Merge |
|---|---|
| Proof of Work (mining) | Proof of Stake (validators) |
| ~112 TWh/year energy | ~0.01 TWh/year energy (−99.95%) |
| ~13,000 ETH/day issuance | ~1,600 ETH/day issuance (−87.5%) |
| Miners received block rewards | Validators receive staking rewards |
| GPU/ASIC hardware required | 32 ETH + validator node required |
| Block time ~13 seconds | Block time exactly 12 seconds |
What Did NOT Change
The Merge specifically did not:
- Lower gas fees (this is a common misconception — gas fees depend on network demand and L2 adoption, not consensus mechanism)
- Enable staked ETH withdrawals (those came in the Shapella upgrade, April 2023)
- Change transaction history — all pre-Merge Ethereum history was preserved
The “Triple Halving” Narrative
Proponents called The Merge a “Triple Halving” because it had roughly three times the supply reduction impact of a Bitcoin halving:
- Bitcoin halvings reduce issuance by 50%
- The Merge + EIP-1559 reduced net ETH issuance by ~80–90% depending on usage
Post-Merge, during periods of high network activity, ETH became net deflationary — more ETH was burned via EIP-1559 than was issued to validators. The term “ultrasound money” was coined to describe ETH’s potentially superior sound money properties vs. Bitcoin.
Ethereum Proof of Work (ETHW) Fork
A small group of miners and supporters refused to accept The Merge and forked the original PoW chain into a separate asset called EthereumPoW (ETHW). The fork launched at roughly the same time as The Merge. ETHW has maintained minimal value and adoption compared to the main Ethereum chain.
Energy Impact
Before The Merge, Ethereum consumed approximately as much electricity annually as Chile (~112 TWh). Post-Merge, Ethereum’s validator network consumes approximately as much as a few thousand home computers. This addressed one of the most common criticisms of blockchain technology — energy waste — at least for Ethereum.
Related Terms
Sources
- Buterin, V. (2020). “Ethereum 2.0: A Complete Guide.” Ethereum GitHub, Ethereum Foundation research.
- Digiconomist / de Vries, A. (2022). “Ethereum’s Energy Consumption Before and After the Merge.” Joule, 6(10).
- Ethereum Foundation (2022). “The Merge: Official Documentation.” ethereum.org, September 2022.
- Wahrstätter, A. et al. (2023). “Blockchain Censorship.” arXiv:2305.18545.
- Coinmetrics (2022). “The Merge: Supply, Issuance, and Long-Term ETH Economics.” Coinmetrics State of the Network Report, September 2022.