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Old 07-12-2014, 01:55 AM   #5 (permalink)
jamesqf
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Quote:
Originally Posted by ecomodded View Post
the back of the iphone should be a solar panel , so its always charging , even with just the office lighting many people sit in.
Humm... Just for numbers, let's say that office (your cube) has light equal to a 100 watt incandescent bulb. But incandescent bulbs are about 5% efficient, so that's 5 watts of energy in the light. Assume it's spread evenly over your 3x3 meter cube, that's 0.56 watts/m^2. A typical phone is about 120x60 mm, or 0.0072 m^2, or 4.03 milliwatts. With a 10% efficient solar cell, that's 0.4 mW of power generated.

But per Google, the iPhone 5S has a max battey capacity of 5966 mWh. so unless my math's off (which it easily could be), it'd take about 15,000 hours to recharge a phone from office lighting.
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