According to a recent study conducted by a utility companies software provider Opower, all that overnight iPhone 6 battery charging to reach a 0 to 100% charge costs only 47 cents a year (via CNN Money). What’s even more interesting is that the study’s estimate may actually be too high, since it assumes you charge your iPhone 6 from 0% to 100% once daily, but some people don’t even empty their batteries every day.
“Don’t believe it’s that cheap? The calculation is actually pretty simple.
Apple’s new iPhone 6 charges from 0% to 100% in 1 hour and 48 minutes, which is about 10.5 watt-hours of energy. Multiply that by 365 days in a year, and you get 3.83 kilowatt-hours. Multiply that by the average U.S. residential electricity price (12.29 cents per kWh), and you get 47 cents per year”.
Similarly, an iPhone 6 Plus costs 52 cents to power up every year, while the iPhone 5 costs just 41 cents for a year’s worth of charging. The reason why they cost so little to charge is because these smartphones, which are built to roughly last a day on a tiny battery, are incredibly low-power devices.
By comparison, a laptop uses 14-times more electricity per year and a desktop computer uses 49 times more.