Cryptocurrencies are often criticized for being bad for the planet. Every year, bitcoin mining consumes more energy than Belgium, according to the University of Cambridge’s Bitcoin Electricity Consumption Index. Ethereum’s consumption is usually pegged at roughly a third of Bitcoin’s, even if estimates vary. Although some 39 percent of the energy going into bitcoin mining comes from renewable sources, according to a 2020 Cambridge report, the industry’s carbon footprint is generally regarded as unacceptable. According to a 2019 study, bitcoin mining belches out between 22 and 22.9 million metric tons of CO2 every year.
The problem is that specialized computers powered by eye-popping amounts of electricity are needed to process and verify transactions of cryptocurrencies like bitcoin or Ethereum’s ether on blockchains, via a process called proof-of-work mining. In this…
