How much energy does Ethereum really use? Cambridge puts a number on it

A new study from the Cambridge Centre for Alternative Finance estimates that Ethereum now uses about 7.87 gigawatt-hours of electricity a year — a rounding error compared with what it consumed as a mining network, and among the most efficient of the major “proof-of-stake” blockchains once you adjust for size.

The reason the number is so small goes back to September 2022, when Ethereum went through an upgrade called the Merge. Before it, Ethereum was secured by mining: computers around the world raced to solve puzzles using power-hungry hardware. The Merge replaced that race with “proof-of-stake,” where participants secure the network by locking up their own ether rather than burning electricity. Earlier estimates found the switch cut Ethereum's energy use by more than 99.9%.

Adjusted for the value of the network, Ethereum used roughly 33 kilowatt-hours per $1 million of market value — the second-lowest figure among the proof-of-stake networks studied, behind only BNB Chain. Solana sat at the other end, at about 283 kWh per $1 million, roughly 8.5 times Ethereum's intensity. Ethereum still burns more electricity in total than most of its peers, simply because it runs so many computers.

Cambridge got there by measuring how much power Ethereum's nodes actually draw. A typical home setup used about 18 watts, a beefier workstation around 153 watts, with an average near 105 watts per node across roughly 8,522 discoverable nodes — about two-thirds of them in cloud or enterprise data centers. The researchers estimated that 56.4% of the electricity behind the network came from renewable and nuclear sources.

The takeaway for beginners: “crypto wastes energy” is one of the most common first impressions, and it is largely true of Bitcoin-style mining — but not of proof-of-stake chains like today's Ethereum. Knowing the difference between proof-of-work and proof-of-stake is one of the more useful things a newcomer can learn, because it changes how you read almost every headline about crypto and the environment. This is information, not investment advice.