As bitcoin struggles to go green, research from Cambridge University showed on Tuesday that the cryptocurrency has made only slim gains in sustainable energy use over the year.
Bitcoin transactions are processed and “mined” by powerful computers, connected to a global network, that compete against others to solve complex mathematical puzzles.
This process reduces electricity consumption, with a heavy reliance on polluting fossil fuels such as coal criticized by policymakers, investors and environmentalists who worry about its impact on global warming.
Projects have sought ways to move bitcoin mining toward clean energy, such as reusing heat byproducts from oil extraction for crypto mining.
Yet fossil fuels made up about 62 percent of bitcoin’s energy mix in January 2022, the latest data available, versus 65% a year earlier, research from the Cambridge Bitcoin Electricity Consumption Index (CBECI) showed.
While coal levels fell from 47% to 37 percent, bitcoin became more reliant on gas, which accounted for a quarter of its energy mix in January, from 16% a year earlier.
The role of sustainable power – classified as nuclear, hydro, wind and solar in the mix – barely increased, from 35 percent a year ago to about 38 percent. Hydro declined from about 20 per cent to 15 per cent.
Bitcoin mining is mostly unregulated and opaque, with few centralized entities collecting data. The Cambridge study was based on data on the geographic spread of mining worldwide and the energy mix of individual countries.
The report said its findings are “significantly deviate” from estimates by the US-based Bitcoin Mining Council industry body, which in July placed the share of sustainable energy in bitcoin’s power mix at around 60 percent.
“We are trying to show what the footprint of bitcoin is,” said CBECI head Alexander Neumueller. “The energy mix actually has a strong impact on greenhouse gas emissions.”
The CBECI said that bitcoin’s greenhouse gas emissions are going to be the equivalent of 48.4 million tonnes of carbon dioxide this year, which is about 14 percent less than the expected emissions for 2021.
© Thomson Reuters 2022
