Gravity Powered Lamp

File this one under ‘why didn’t I think of this’ : a lamp that uses gravity as a source of power! To activate the lamp, you put weights in at the top, and those weights push down a rotor, causing it to spin. This spinning motion creates electricity that powers ten LED lights. The lamp runs for four hours per cycle, and produces as much light as a 40 watt incandescent bulb. It has a life expectancy of 200 years if used for eight hours a day.

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