how much energy is used for my iPhone to charge?
when i plug my iphone into the wall to charge it, how much energy is passed from the wall to my iphone before its fully charged??
i'm writing a blog entry about solar iphone cases, and i'd like to try and calculate how much energy you'd save or how much carbon you'd offset if you used a solar charger to juice your iphone for a year instead of the walljack.
- 9 years agoFavorite Answer
4 to 6W for iphone 2 and 3
I have 3G-S and if I use it for phone calls or mp3 it needs charging every 1-2 days.
- 9 years ago
My iPhone 3GS draws 4W when charging, according to my kill-a-watt power meter.
(as for your blog entry - you'd need to know how long your phone charges over the course of a year, as well. It presumably is not plugged in (or charging) all the time. As for the carbon offset, I imagine it is very little, especially when you consider transport of the solar case from China and the 2-year lifetime it'll probably have before it's discarded when the new iPhone model arrives... FWIW, It's been estimated that the "unplug your cell charger" suggestion saves enough carbon each day to offset driving your car for about 1 second)
On edit - I see you asked for energy and I gave you an answer for power. :) So here's energy.
Let's assume you charge it for 1 hour each day, and it draws 4W for that hour.
1 (hour) * 4 (watts) * 365 (days in a year) gives 1460watt-hours, or about 1.5kWh in a year. If that's generated with coal (about 2 lbs CO2 per kWh) that's about 3 pounds of CO2.Source(s): http://www.eia.doe.gov/electricity/page/co2_report... http://www.inference.phy.cam.ac.uk/withouthotair/c... http://www.inference.phy.cam.ac.uk/withouthotair/c...