# Cambridge Blockchain Network Sustainability Index

Source: https://ccaf.io/cbnsi/ethereum
Kiwi News: https://news.kiwistand.com/stories/Cambridge-Blockchain-Network-Sustainability-Index?index=0x679dfea7c944d6cecf65019d3b0c9bf0cbe668fe3ef9083193169a93c0056baf1426750c
Submitted by pfedprog.eth on 2025-02-01 UTC, 1 upvote, 0 comments

## Summary

The Cambridge Blockchain Network Sustainability Index estimates electricity use attributable to Ethereum's consensus layer, not its pre-Merge proof-of-work period, which the graph does not cover. Estimates start on 12 December 2021, the first date Beacon Node count data was available, although the Beacon Chain launched on 1 December 2020. A network monitoring tool upgrade effective 6 March 2023 revealed significantly more Beacon Nodes, causing a noticeable uptick in estimated electricity usage from that date. Figures apply a 7-day moving average to smooth short-term node count volatility.

## Article

Note: A 7-day moving average is applied to reduce the effect of short-term Beacon Node count volatility. Please bear in mind that this graph does not show historical electricity consumption estimates of the Ethereum Mainnet before The Merge. For estimates on the electricity consumption of Ethereum when it still followed the proof-of-work consensus, you can visit the segment Ethereum 1.0 (PoW) for more information.

The estimates shown in the graph, dating back prior to The Merge, illustrate electricity consumption attributable to the consensus layer. While the Beacon Chain was launched on 1 December 2020, data on the number of Beacon Nodes was only available to us as of 12 December 2021, which also marks our first data point. Effective 6 March 2023, we have upgraded to the second iteration of the network monitoring tool that provides key data for our electricity consumption estimate. The new version contained multiple improvements, but also led to the discovery of a significantly larger number of Beacon Nodes, which resulted in a noticeable uptick in electricity usage from that date.

Note: monthly or yearly consumption figures are the sum of daily consumption figures calculated by assuming constant power usage over 24 hours at the daily best-guess estimate of Ethereum’s network power demand. The cumulative consumption is the sum of monthly or yearly totals since the start of the model on 12/12/2021. Please bear in mind that this graph does not show historical electricity consumption estimates of the Ethereum Mainnet before The Merge. For estimates on the electricity consumption of Ethereum when it still followed the proof-of-work consensus, you can visit the segment Ethereum 1.0 (PoW) for more information.