The Cambridge Centre for Alternative Finance (CCAF) reports that Ethereum’s annual energy consumption and carbon emissions have declined by over 99.9% following The Merge in 2022, marking a significant shift in the network’s environmental profile.
Ethereum’s energy demand falls after moving to Proof-of-Stake
According to the latest CCAF research, Ethereum now consumes around 7.87 gigawatt-hours (GWh) of electricity per year. This represents a dramatic drop from the estimated 8.88 terawatt-hours (TWh) annually prior to The Merge, when Ethereum operated on a Proof-of-Work (PoW) validation system.
The Merge was Ethereum’s transition from the energy-intensive PoW framework, where miners competed using computational power, to Proof-of-Stake (PoS), which relies on validators securing the network by staking ETH. With PoS, energy-hungry mining rigs were eliminated in favor of more sustainable and efficient mechanisms for maintaining network integrity. The report estimates Ethereum’s current continuous power draw at 0.90 megawatts, compared to 2.4 gigawatts immediately before the switch.
CCAF also says Ethereum’s annual greenhouse gas emissions have dropped to about 2.37 kilotonnes of CO₂ equivalent (ktCO₂e), reflecting a near-total decline from previous levels.
To provide further context, CCAF compared Ethereum’s electricity usage to that of the British Museum, which consumes about 16.18 GWh per year. Ethereum’s current figure is less than half of that, illustrating how significantly the network’s power consumption has fallen.
The Cambridge Centre for Alternative Finance assessed Ethereum’s new energy profile, noting its “electricity consumption and carbon emissions have fallen by more than 99% since it migrated to Proof-of-Stake, transforming its environmental footprint to a level well below that of small public institutions.”
| Metric | Before The Merge (PoW) | After The Merge (PoS) |
|---|---|---|
| Annual electricity use | 8.88 TWh | 7.87 GWh |
| Continuous power demand | 2.4 GW | 0.90 MW |
| CO₂ emissions | Approx. 10,000 ktCO₂e | 2.37 ktCO₂e |
Infrastructure and node distribution data
The CCAF report is based on a comprehensive audit of about 8,522 Ethereum nodes distributed globally. This analysis focuses on actual hardware and internet hosting, rather than theoretical assumptions.
Ethereum nodes act as data processors, maintaining the ledger’s integrity and sharing updates. These differ from the network’s roughly 894,000 validators, who secure Ethereum by locking up staked ETH and confirming transactions.
The study determined that the average energy use per node is approximately 105 watts. For residential setups, the median is 18 watts. Energy requirements increase with larger and enterprise-level deployments.
Mini dictionary: Cambridge Centre for Alternative Finance (CCAF), an academic research institute at Cambridge Judge Business School focusing on global financial technology, digital assets, and alternative finance trends.
Carbon intensity depends on grid and hosting
The United States currently hosts 31% of Ethereum’s full nodes, followed by Germany with 16%, Finland with 8%, and France with 6%. Together, these four countries account for about 62% of the network’s full nodes.
CCAF estimates that 36% of nodes run on residential hardware, while the remaining 64% are hosted in cloud or enterprise data centers. In particular, Hetzner, Amazon Web Services, and OVH collectively account for approximately 40% of all node hosting.
The study shows that 56.4% of Ethereum’s electricity is sourced from sustainable energy, with 39.4% coming from renewables and 17.0% from nuclear power. The largest single contributor remains natural gas at 27.7%.
According to the report, the main factor influencing Ethereum’s carbon footprint now is the carbon intensity of local power grids serving the nodes. This means network location has become more important than the underlying consensus protocol for determining environmental impact.
