According to Yahoo News, a University of Cambridge study has revealed that the historical greenhouse gas emissions of the Ethereum blockchain before its major software upgrade in 2022 were equivalent to the yearly emissions of Honduras. Blockchains, the digital ledgers underpinning cryptocurrencies, are known for their high energy consumption during coin production and transaction processing, leading to criticism from environmentalists and some investors. However, accurately determining the environmental impact of the crypto sector is challenging due to its opacity and lack of centralized data.
In September 2022, the Ethereum blockchain, which hosts the world's second-largest token ether, underwent a significant software upgrade called the 'Merge,' which drastically reduced its energy usage. The study found that from its launch in 2015 until the Merge, Ethereum's greenhouse gas emissions totaled 27.5 million tonnes carbon dioxide equivalent (MtCO2e), while Honduras emitted 27.7 MtCO2e in 2020, according to Climate Watch. Ethereum now uses over 99% less energy under its post-Merge system, with its current yearly emissions at around 2.8 kilotonnes carbon dioxide equivalent, which is roughly the same as five round-trip flights from London to New York.
Anna Lerner, executive director at the Ethereum Climate Platform, stated that blockchain is often considered a high-emitting technology, but Ethereum has demonstrated that it doesn't have to be a significant polluter. The study, conducted by Alexander Neumueller, research lead for digital assets climate impact at the University of Cambridge, is among the most comprehensive examinations of Ethereum's historical emissions. In comparison, Bitcoin, the largest blockchain and cryptocurrency, generates about 73.9 MtCO2e annually, which is approximately equivalent to Cambodia's emissions in 2020, according to Climate Watch.
