ZDNet recently did some interesting research. Adrian Kingsley-Hughes wanted to know how much it would cost in electricity to charge an iPhone 6 Plus for a year. He chose this model because it has the biggest capacity battery Apple offers in an iPhone. The result will shock you (pun intended).
On average, during an overnight charge, the iPhone consumed an average of 19.2 Wh. According to figures published by the US Energy Information Administration for January 2016, the average cost per kWh in the US was $0.12. Remember that 1 kWh equals 1,000 Wh. So, take our average of 19.2 Wh per day, multiplying that by 365 days, we get 7 kWh, which works out at $0.84 a year. So if you guess under a dollar, well done.
That’s right, it costs less than a dollar for an entire year. The more you know!
Check It Out: How Much Does it Cost to Charge an iPhone For a Year?
Answering some of my own questions, FYI.
1. It turns out that wireless charging is about 75% as efficient as charging with a cable:
https://batteryuniversity.com/learn/article/charging_without_wires
2. Qi standard charging pads go into “standby” mode when the battery charge reaches 100% (same reference).
There may be more up-to-date information out there but it seems that wireless charging comes with an efficiency cost.
Andrew, were figures in the ZDnet article based on wired or wireless charging?
My bad, I totally forgot about your first comment. The figures were based on wired charging.
I recently purchased an iPhone XS with a Logitech wireless charging stand which raised two questions in my mind. Maybe you know the answers.
1. Is wireless charging as efficient as charging with a lightning cable? It’s conceivable there might be some loss in efficiency with wireless charging due to the air and materials between the phone and charging stand.
2. Do wireless charging stands turn off once the iPhone is fully charged? If not, it would less efficient the longer the phone was left on the charging stand.