How much energy does bitcoin use?

How much electricity does bitcoin consume globally? The answer is important not only for the health of the planet, but also for the currency’s value.

Researchers start by looking at the bitcoin network’s daily “hashrate”—i.e., how quickly computers on the network can perform calculations. Then they make some assumptions about the computer equipment most miners are using.1 Throw in an estimate of average electricity prices and the latest price for bitcoin, and you can get an accurate, if imprecise, estimate of electricity consumption. The most reputable such estimate comes from the University of Cambridge Bitcoin Electricity Consumption Index, according to which the global bitcoin network currently consumes about 80 terawatt-hours of electricity annually, roughly equal to the annual output of 23 coal-fired power plants, or close to what is consumed by the nation of Finland.

Bitcoin’s energy use compared to a battery.

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