Bitcoin’s energy usage is huge – we can't afford to ignore it

The cryptocurrency uses as much CO2 a year as 1m transatlantic flights. We need to take it seriously as a climate threat

Bitcoin’s electricity usage is enormous. In November, the power consumed by the entire bitcoin network was estimated to be higher than that of the Republic of Ireland. Since then, its demands have only grown. It’s now on pace to use just over 42TWh of electricity in a year, placing it ahead of New Zealand and Hungary and just behind Peru, according to estimates from Digiconomist. That’s commensurate with CO2 emissions of 20 megatonnes – or roughly 1m transatlantic flights.

That fact should be a grave notion to anyone who hopes for the cryptocurrency to grow further in stature and enter widespread usage. But even more alarming is that things could get much, much worse, helping to increase climate change in the process.

Bitcoin is the first, and the biggest, "cryptocurrency" – a decentralised tradable digital asset. Whether it is a bad investment is the big question. Bitcoin can only be used as a medium of exchange and in practice has been far more important for the dark economy than it has for most legitimate uses. The lack of any central authority makes bitcoin remarkably resilient to censorship, corruption – or regulation. That means it has attracted a range of backers, from libertarian monetarists who enjoy the idea of a currency with no inflation and no central bank, to drug dealers who like the fact that it is hard (but not impossible) to trace a bitcoin transaction back to a physical person.