Quote:Safer than kerosene and cheaper than solar, the GravityLight could help illuminate thousands of households in developing countries. Supporters can get a GravityLight of their own to try out.

The GravityLight shines a light on problems with kerosene.
(Credit: GravityLight)

It's easy to take our electric lights for granted. Many people in developing counties don't have the luxury of electric grids and have to rely on kerosene lamps to brighten the night. Kerosene costs money and breathing the fumes is dangerous. A new light powered by gravity could be a superior solution to lighting needs.

GravityLight doesn't need to be recharged through solar cells. It doesn't use batteries at all. It's powered by the same force that keeps our feet on the ground. A weight attached to the light takes 3 seconds to lift up, but provides 30 minutes of light as it descends.

(12-15-2012 02:24 PM)bitcruncher Wrote:  Here's an interesting development. I wonder what utility companies will think if this technology takes off...

(12-16-2012 10:34 PM)PirateTreasureNC Wrote:  Maybe I over looked it but what about the descending weight gives the light power? And I guess, what keeps the light from going up and down and also what sets up the weight's motion?

(12-16-2012 11:48 PM)RaiderATO Wrote:  

(12-16-2012 10:34 PM)PirateTreasureNC Wrote:  Maybe I over looked it but what about the descending weight gives the light power? And I guess, what keeps the light from going up and down and also what sets up the weight's motion?

I'd assume it the same idea as a crank powered weather radio or flashlight. Just creating an electro-magnetic current from magnets.

The weight slowly falls over the ~30min (or less and the stored energy lasts out the 30 min.. Can't tell.)

Someone picks it up and places it higher up on the "chain" that pulls the internal gears.

(12-17-2012 09:22 AM)bitcruncher Wrote:  

(12-16-2012 11:48 PM)RaiderATO Wrote:  

(12-16-2012 10:34 PM)PirateTreasureNC Wrote:  Maybe I over looked it but what about the descending weight gives the light power? And I guess, what keeps the light from going up and down and also what sets up the weight's motion?

I'd assume it the same idea as a crank powered weather radio or flashlight. Just creating an electro-magnetic current from magnets.

The weight slowly falls over the ~30min (or less and the stored energy lasts out the 30 min.. Can't tell.)

Someone picks it up and places it higher up on the "chain" that pulls the internal gears.

If you had read the article, you'd have seen that all they needed to do to activate the light again was pull the string to get the weight back up.

(12-17-2012 10:17 AM)bitcruncher Wrote:  Not exactly...

(12-17-2012 11:22 PM)georgia_tech_swagger Wrote:  Notice it is riding on rails with holes. I'm going to guess that those holes turn internal gears which convert that slow turn into a VERY rapid turn of magnets around a copper wire core to generate electricity. To overcome the mechanical inertia of that sort of gearing, it probably has a goodly amount of lead weight in it (~10 ibs). It probably has a method to disengage the gearing to hoist it back up without fighting the gearing.