Bitcoin, trumpeted by many as the currency of the future, continues to add to its carbon footprint.
A study released yesterday by the Technical University of Munich and MIT found that Bitcoin’s carbon footprint was between 22-22.9 megatons of carbon dioxide emissions per year. That is equivalent to the carbon footprints of cities such as Kansas City or Las Vegas, and is between the carbon emissions of Jordan and Sri Lanka.
Much of the carbon footprint comes from Bitcoin “miners,” or those on the service who validate the transactions. The “miners” are tasked with validating the transactions made on a service, and is done in a randomly-generated fashion for each of the miners. This process, commonly referred to as “blockchain technology,” requires a large amount of computer power and nonrenewable resources to get the job done.
In the past, estimates have been hard to come by, as there was plenty of knowledge missing about the types of machines being used, as well as the extent of use. In addition, the data miners were “decentralized” and did work remotely on a single computer, making it hard to get the carbon footprint of computers scattered around the world.
Two developments allowed for this study to get a more accurate estimate. First, three major Chinese mining hardware companies filed for initial public offerings, giving the research team access to documents that gave a very accurate estimate into what types of machines were used and where. In addition, the mining sites themselves are more centralized, as now the majority of the mining is done in “pools” or large groups. This makes it much easier to locate and track the energy usage for producing Bitcoin.
Christian Stoll, the lead researcher on the paper, said that because of these developments, this paper goes “beyond prior work” and can provide “empirical evidence where current literature is based on assumptions.” Others, including Bitcoin expert Alex de Vries, say the estimate is conservative if anything.
The estimate poses a challenge for the currency, as it can add a significant amount to our carbon footprint. Stoll concluded that while blockchain technology could be more efficient in the future, “more attention needs to be given to the costs” of blockchain.
