Question

What is the power rating of your cell phone? How much coal is required per year to allow for your cell phone habits? How much does this cell phone’s electricity cost you per year?

Answer 1

Cell phones, mobile phones, even smart phones and tablets are very energy efficient because they are designed to run on a battery for a long period of time. Cell Phones use approximately 2 to 6 watts when charging, while a charger left plugged in without a phone will consume 0.1 to 0.5 of a watt. Charging an iphone or android phone under normal use conditions will typically cost under a dollar for a full year.

Charging a cell phone is not a very significant source of energy consumption. Unplugging your phone charger may save a little bit of energy, but even if you left a plugged in charger without a device which is consuming half a watt 24/7 for a full year, it will only cost you 44 cents a year @ 10 cents per kWh.