Charging the iPhone 6 is one of the least expensive things you'll do all year

Opower has looked into the issue and has concluded that it takes 10.5 watt-hours of electricity to fully charge the iPhone 6 once. Assuming you charge it once per day, every day for one year, that comes out to be 3832.5 watt-hours (aka 3.8325 kilowatt-hours). If you take the U.S. average cost of electricity as 12.29 cents per kilowatt-hour, that adds up to a mere $0.47 per year to charge your iPhone 6. The iPhone 6 Plus and its bigger battery would cost $0.52 per year, because it would require about 4.2 kilowatt-hours. There aren't many things that you have to pay for that only cost 50 cents per year. 

The numbers may be tiny on an individual level, but when you consider that Apple sold 10 million iPhones in the first weekend, that alone makes up about $5 million in energy costs. That's a sobering thought, considering a smartphone is one of the least power-hungry devices in your home, and also considering that the average person in Haiti uses just 32 kilowatt-hours of electricity in total for one year. 

The big trouble with the study is that the only comparison it gives is to the iPhone 5, which cost $0.41 per year to charge. We would have loved to see these numbers for other popular phones in the Android and Windows Phone world. The cost appears to be somewhat correlated to battery size, but at a certain point, you could start charging every other day, which would bring the cost back down again. So, we would assume there are some devices out there that would cost significantly less than an iPhone to charge. 

source: Opower via BGR