Bitcoin is the least energy-efficient cryptocurrency, using 707.6 kilowatt-hours of electricity per transaction. Mining for proof-of-work cryptocurrencies requires enormous amounts of electricity and consequently comes with a large carbon footprint. Proof-of-work blockchains such as Bitcoin, Ethereum, Litecoin, and Monero were estimated to have added between 3 million and 15 million tonnes of carbon dioxide to the atmosphere in the period from 1 January 2016 to 30 June 2017. By November 2018, Bitcoin was estimated to have an annual energy consumption of 45.8TWh, generating 22.0 https://knoxydmb164.skyrock.com/3349282882-Bitcoin-Prices-Plunge-As-600-Billion-Crypto-Market-Crash-Accelerates.html to 22.9 million tonnes of CO2, rivalling nations like Jordan and Sri Lanka.
