Ethereum’s shift from proof-of-work to proof-of-stake appears to have produced a dramatic reduction in electricity use, according to a new report from the Cambridge Centre for Alternative Finance. The study says the network’s power demand dropped by roughly 99.98% after The Merge in September 2022, alongside a similarly sharp fall in estimated emissions.
The report, titled Ethereum after the Merge: A Change in Power, examines how Ethereum’s energy profile changed once the network abandoned mining-based consensus. Before the transition, Cambridge estimates Ethereum’s power demand was about 2.4 gigawatts, a level the report compares to the electricity needs of a small country such as Iceland.
Post-Merge power profile
After the consensus change, Cambridge says Ethereum’s power demand fell by about 3.5 orders of magnitude. The report estimates annual electricity use at 7.87 gigawatt-hours, which it also expresses as roughly 0.90 megawatts on a daily basis.
That marks a steep decline from the network’s pre-Merge energy requirements and reflects the very different infrastructure needed under proof-of-stake. Cambridge describes the change as the result of a single architectural software shift rather than a gradual efficiency improvement.
Emissions estimate also dropped
The report pairs the energy findings with a large reduction in emissions. It estimates Ethereum’s footprint fell from 10.3 million tonnes of CO2 to 2.37 kilotonnes of CO2 equivalent after the transition, again amounting to a drop of about 99.98%.
As presented by Cambridge, the emissions decline tracks the reduced power demand that followed the end of proof-of-work mining on Ethereum. The report does not frame the network as energy-free, but it does portray the post-Merge version of Ethereum as substantially less resource-intensive than before.
How Cambridge measured it
Cambridge says its estimates are based on a network-weighted average of 105 watts per node. Using that approach, the center places Ethereum below some other blockchain networks in power demand, including Solana, while saying it remains above others such as NEAR.
The report also argues that Ethereum should be viewed not only in absolute power terms but in relation to the scale of activity it supports. While it still counts Ethereum among larger energy users in absolute terms, Cambridge says the network is comparatively efficient relative to its economic weight.
Comparison with other systems
To illustrate that point, the study compares Ethereum with traditional finance and with major cultural and digital platforms. It says the legacy banking system consumes about 260 terawatt-hours per year, compared with Ethereum’s 7.87 gigawatt-hours, or 0.0079 terawatt-hours. On that basis, the report says Ethereum’s energy intensity is roughly 33,000 times smaller.
Cambridge also states that Ethereum’s post-Merge footprint is below the energy consumption of the British Museum and only a fraction of what global streaming services such as Netflix require.
The findings add another data point to the debate over how blockchain networks should be assessed after major technical changes. In this case, Cambridge’s analysis suggests Ethereum’s 2022 redesign sharply altered its power and emissions profile, while still leaving the network measurable enough to compare with rival chains and established financial infrastructure.
Source: news.bitcoin.com