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0 pointsSomeone13y ago0 comments

Neither would fix it. http://en.wikipedia.org/wiki/Orders_of_magnitude_(power) gives 909W for "peak output power of a healthy human (nonathlete) during a 30-second cycle sprint at 30.1 degree Celsius."

This thing talks about a 1:600 duty cycle (3 seconds of charging for 1800 seconds of lighting), so, at the very best, it could use a 1.5W LED. Looking a a more realistic 100W human power output (Tour de France riders do 6W/kg or so sustained), it's gets down to .1W or so.

A heavier weight, more height, or more frequent charging all will increase the amount of light produced, but it also means less time to enjoy it.

In the end it all boils down to the fact that a kWh is a lot of energy for a human to produce.

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pdonis13y ago

If you're trying to produce light equivalent to what we're used to in first world countries, yes, you're right.

If you're only trying to replace kerosene lamps, you don't need much power. A tenth of a watt with an LED gives a light output comparable to a kerosene lamp. See the numbers elsewhere in the thread.

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