Gravity energy storage is not exactly at the center of energy-related debates. However, it does have some admirable qualities. One is that such systems can be designed to last a lifetime. This is very important to everyone, of course, but especially to those living in impoverished parts of the world.
A so-called “gravity-powered” LED lamp, GravityLight, has been created that generates its own electricity with the assistance of gravity… although it is not completely gravity powered.
This is a human-powered LED. Like “wind-up” radios, this can be powered by bare human hands, and it works.
I am not going to label this as just another “wind-up” device, or “old technology,” because it is more convenient, and it’s addressing a critical need of the day. Plus, this device seems to work very well.
When those older, hand-wound devices I mentioned got old, their batteries malfunctioned and they would have to be cranked many times, and for a long time in order to get much out of them.
This LED uses no batteries or fuels. This means that it has the potential to last a very long time, if built well.
How The GravityLight Works
To use the GravityLight, the user lifts a heavy weight attached to the lamp by pulling a rope for about 3 seconds, and then the LED operates for 30 minutes before the rope needs to be pulled again.
The weight is a bag that can be filled with rocks, or any other material, as long as it is heavy enough to pull the rope down and turn the LED lamp’s internal generator.
The generator uses gears to achieve the rotational speed it requires. Exactly how that is done, is not stated.
Normally, people would use the rope to turn a large overdrive gear slowly, and that large gear turns a much smaller gear. Due to the fact that the small gear is so much smaller, it turns at a very high-speed. So the large gear provides a large amount of torque at an extremely low-speed, and that torque is converted into a higher rotational speed (but with less torque) suitable for the generator using this arrangement. I can only guess that this is how this lamp was built, based on the nature of this type of device.
Source: Smart Planet
I have a keen interest in physics-intensive topics such as electricity generation, refrigeration and air conditioning technology, energy storage, geography, and much more. My website is: Kompulsa.