By Evan Ackerman
Clay Moulton, a student at Virginia Tech, has designed this Gravia floorlamp to be powered completely by gravity. The lamp contains a 50 pound brass weight which is placed 48″ above the ground, and as the weight descends over a period of 4 hours, it drives a generator to power an array of 10 LEDs which diffuse through the lamp, providing a soft white light equivalent to a 40 watt bulb. Now, if you think about it just a little bit, you realize who’s really doing the powering: you are, as the chump who has to lift the weight back up every 4 hours. It’s essentially the same as a clock that uses weights and a pendulum, or effectively the same as a wind-up flashlight. That’s not to say it’s not a cool lamp; besides being cordless and independent of the power grid, it does offer a few other novel benefits:
Moulton estimates that Gravia’s mechanisms will last more than 200 years, if used eight hours a day, 365 days a year. “The LEDs, which are generally considered long-life devices, become short-life components in comparison to the drive mechanisms,” he said. The acrylic lens will be altered by time in an attractive fashion, Moulton said. “The LEDs produce a slightly unnatural blue-ish light. As the acrylic ages, it becomes slightly yellowed and crazed through exposure to ultraviolet light,” he said. “The yellowing and crazing will tend to mitigate the unnatural blue hue of the LED light. Thus, Gravia will produce a more natural color of light with age.”
It’s currently just a concept, but if it ever gets produced, you’ll have to decide which source you’d prefer to power your lights: your hard work, or some power plant somewhere that you don’t have to lift off the ground several times a day.