As blockchain technology continues to gain momentum, its potential environmental impact has come under scrutiny. While energy-intensive proof-of-work (PoW) networks like Bitcoin consume vast amounts of electricity, proof-of-stake (PoS) networks are often touted for their energy efficiency. But how much truth is there to these claims of low energy consumption by PoS blockchains? A recent study seeks to shed light on this question by replicating, expanding, and improving existing research estimating the energy footprint of major PoS networks.

The study first replicates the methodology of a 2021 paper by Platt et al. which modelled the energy consumption per transaction for leading PoS networks based on their throughput and number of validators. It then expands the analysis to cover more networks, including newer ones like Avalanche, BNB Chain, and Toncoin. More data points are added, spanning a longer timeframe compared to the original study. The energy consumption assumptions per validator node are also updated with real-world measurements where possible.

The findings reaffirm that PoS systems are orders of magnitude more energy efficient than PoW networks like Bitcoin. However, significant differences emerge across the PoS networks analyzed. For instance, Cardano displays a relatively high energy cost due to its large validator set and low throughput. Solana’s energy footprint appears substantial at low throughputs but more efficient at higher loads.

Since energy consumption per transaction varies hugely with throughput, the study models consumption as a function of throughput. It confirms the hypothesis that validator counts and throughput are positively correlated, with some caveats. The Ethereum Merge led to a massive drop in its power demands, with energy use per transaction falling from 0.00803 kWh to 0.00026-0.0007 kWh.

While validating the usefulness of this estimation method, the study also highlights limitations like its simplicity, limited predictive power, and inability to account for factors like transaction types. The short observation period means long-term relationships are hard to discern. Nevertheless, it provides a valuable first step towards fair energy consumption comparisons between PoS networks, while underscoring the need for further research.

Overall, the analysis debunks claims that all PoS networks have similar efficiency. But it reaffirms that their energy demands are negligible compared to PoW, regardless of differences. As PoS adoption grows, refining such estimates will be essential to inform developments and assess environmental impact. With climate concerns paramount, scrutinizing the carbon footprints of emerging technologies is vital, making studies like this timely and relevant.

This article is based on recent research done by blockchain researchers, available here