"Cryptocurrencies have emerged as one of the most captivating, yet head-scratching, investments in the world. They soar in value. They crash. They’ll change the world, their fans claim, by displacing traditional currencies like the dollar, rupee or ruble. They’re named after dog memes.
And in the process of simply existing, cryptocurrencies like Bitcoin, one of the most popular, use astonishing amounts of electricity.
We’ll explain how that works in a minute. But first, consider this: The process of creating Bitcoin to spend or trade consumes around 91 terawatt-hours of electricity annually, more than is used by Finland, a nation of about 5.5 million. "