Cryptocurrency mining is often characterized as an act of solving a set of complex equations, evoking images of a Red Bull-guzzling genius hunched over a calculator searching for the Bitcoin-creation formula. But actually it’s less about calculation than it is about trial and error — making guesses in hopes of landing on a random, 64-digit number. Whoever has the most energy-intensive computing power can make the most guesses in a short time frame, and whoever makes the most guesses likely will solve the puzzle first, and will be rewarded for their “proof of work” with one of a finite number of bitcoins. Or, to put it another way, the more power one uses, the more likely they are to hit the jackpot. As the value of each cryptocurrency increases, so does the number of miners. More miners means more computing power means more electricity consumed. Some cryptocurrencies are considering moving away from “proof of work” to a “proof of stake” system that uses less electricity but is also less secure.

In the early days of Bitcoin’s creation, people could “mine” the coins using a powerful standard desktop computer. But with each bitcoin that is mined, the process of acquiring the next one requires more computing power and therefore more energy. Now that 18.5 million of the 21 million bitcoins in existence have been mined, only huge banks of cryptocurrency mining “rigs” can provide enough computing power to be successful. That, in turn, requires huge amounts of energy.