A Virginia Tech student has invented a floor lamp that runs on gravity. The unit is bit over four feet high and will put out the same amount of light as a 40 watt light bulb for over four hours at a time. The lamp, if run eight hours a day, 365 days a year, will last over 200 years.
“To “turn on” the lamp, the user moves weights from the bottom to the top of the lamp. An hour-glass like mechanism is turned over and the weights are placed in the mass sled near the top of the lamp. With the sled gently gliding back down, within a few seconds, the LEDs come on and light the lamp, Moulton said.”