The emissions associated with mining a single bitcoin have increased 126-fold in five years, creating an industry that, according to one measure, is more environmentally damaging聽than global beef production.
Mining bitcoin involves networks of computers competing to guess the solution to a mathematical puzzle. The process authenticates the cryptocurrency鈥檚 transactions, and the first miner to the solve the puzzle is awarded a significant amount of bitcoin. 鈥淏ecause it鈥檚 worth a lot of money, you have a lot of people who are engaging in this guessing game,鈥� says at the University of New Mexico. 鈥淭hat鈥檚 using a lot of electricity and most of that electricity is coming from fossil fuels.鈥�
To estimate the climate burden associated with mining, Jones and his colleagues first tallied the total number of coins mined daily between 2016 and 2021. Then, they accounted for miners鈥� locations and the amount and type of energy they probably would have used to estimate the carbon emissions per coin.
Advertisement
Their work revealed that carbon emissions skyrocketed from 0.9 tonnes per coin in 2016 to 113 tonnes per coin in 2021 鈥� a 126-fold increase. They estimated that each coin mined in 2021 would have an associated cost to the climate of over $11,000.
Part of the reason for this escalating environmental cost is that more people are attracted to mining as bitcoin鈥檚 value rises. The cost of a single bitcoin jumped from around $430 at the start of 2016 to over $46,000 by the end of 2021.
Jones and the team then looked at how much a bitcoin is worth compared to the environmental damage associated with mining it and compared that to other industries. The researchers found that every $1 of bitcoin mined between 2016 and 2021 led to $0.35 in climate damages. In the same time period, every $1 worth of petrol produced from crude oil created $0.41 in climate damages, while beef production cost around $0.33 per dollar.
The results help to contextualise the 鈥渆nvironmental disaster that bitcoin and several other cryptocurrencies are creating, passing largely unnoticed鈥�, says at the University of Hawaii. 鈥淕overnments really need to start regulating and putting environmental standards on the use of cryptocurrencies.鈥�
Changing how bitcoin is mined could make the competitive process less energy intensive. The popular cryptocurrency Ethereum made a sweeping climate-friendly revision to its model earlier this month and Jones hopes bitcoin is next, despite significant hurdles that make the switch unlikely. 鈥淚f you change the rules of the game, you can change the energy use,鈥� says Jones.
Scientific Reports
