Bitcoin Is Unsustainable — Christopher Malmo, motherboard.vice.com
Computer cooling firm Allied Control estimates the total power consumption of the Bitcoin network at 250 to 500 Megawatts. Looking at the total hashrate, which is the number of calculations the network can perform per second, and applying a generous miner efficiency of 0.6 watts per gigahash, we can estimate our own back-of-the-envelope Bitcoin network constant power draw at just under 215 MW, although this figure is always in flux (it’s important to note that many of the variables in my calculation are constantly changing slightly). That’s around enough zap to power 173,000 average American households’ daily electricity usage.
With about 110,000 transactions per day, that works out to 1.57 households daily usage of electricity per Bitcoin transaction. Yes, every time you buy something in Bitcoin, you could be using as much electricity as 1.57 American families do in a day.