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'Gravity Lamp' lasts 200 years, never needs to be plugged in
gravia_w_person_cutout.jpgA Virginia Tech student has won the Greener Gadget Award for a clever LED lamp that gets all of its power from gravity, which is a seriously renewable resource. Working kind of like a grandfather clock that needs to be wound in order to work, the lamp has a weight that's raised up every day. As the day goes on, it slowly lowers, with that movement powering the LEDs.

Dubbed the Gravia, the lamp will stand about four feet tall. Encased in glass, the entire thing is lit with a soft, diffuse glow that comes from the 10 built-in LEDs. Because it's self sufficient, there are no cables or cords to worry about, so you can place it anywhere. The best part? It'll last for 200 years if used 8 hours a day, 365 days a year. You'll never buy another lamp again; it doesn't get much more green than that.

Greener Gadgets, via Sawf

         
Comments

Not to pick nits, but wouldn't it be more accurate to say that the thing gets all its power from whatever you ate for breakfast, since you're the one bending over to hoist the weight back up to the top of the thing? My vague recollection of high school physics would indicate that we're talking about a closed-loop conversion of kinetic to potential (back to kinetic, thus to light + heat) energy here.

Sounds like ross' breakfast consisted of some urine flavored cheerios.

So couldnt this thing have 2 weights? One to power the light and one to store up enough energy to reset the device at the end of the day. This way nothing needs to be done with it ever.

How much? Incredible potential! How do I invest?

DinoRoger . . . do you have to wear a helmet when you use the internet?

Why couldn't it have ten weights, and be a limitless supply of free energy? We could hook the whole grid up to it!

Urine Flavoured Cheerios! Now THATS energy efficiency!

The generator and ratchet mechanism are going to last 200 years? Grandfather clocks can run continuously for decades because they get wound once a week, and draw only a few milliwatts.

Props to the inventor. However, as Wyle_E mentions, there is no way the mechanism will last 200 years, even if the LEDs do. If it's built like a first-rate swiss watch, it might last decades. And as RossGrady said, it actually gets its power from the person who lifts the weight each day. And DinoRoger, please go read some physics 101 books.

Well, Rossgrady, if we are going to be pedantic, I'll go one better and say that it DOES get its power from gravity, because if it weren't for gravity the owner wouldn't HAVE TO lift the weight every day, and it wouldn't fall every day. In fact it wouldn't even work, or even exist.

to be even more pedantic kage, gravity is what converts the potential energy in the weight to kinetic energy. the potential energy is supplied to the weight by the person who is turn got their energy from their food. gravity is a transducer here. it doesn't supply any energy

to not be pendantic, i like it. i'd buy it. i'd use it. i wouldn't argue about it.

Has anyone done the math on this? I don't know what is more ridiculous, this idea or the fact that it won first prize. I would not enjoy lifting a 3,200 pound weight every 4 hours to power ten measly LEDS. Conservatively assuming the 10 LEDS pull 1 watt of power for 4 hours (14400 secs), we need 14400 joules of energy. If the magical lamp was 100% efficient we would need to lift 1469.39 kg one meter to supply the energy for 4 hours = Ridiculous.

Hey Ridiculous, I think you might want to re-do your equations. Just looking at the picture, I'm guessing the weight is about 5 - 10 pounds.

The conference organizers must feel pretty silly giving an award to such a bogus bit of design. 50 lbs (5x10-lb brass weights, read the picture) raised 60″ in Earth’s gravity gives a total energy of 346 Joules, or .025 Watt over 4 hours (that’s 0.1 W-hr). The best LEDs available today produce 200 lumens / Watt. In short, Clay’s Moulton’s Gravia will run for about 1 minute, not 4 hours. It's also one of the core bits of his Master's thesis, so his Graduate Committee should also feel pretty dumb for missing an error of this magnitude (2 to 3 orders, to be exact).

...Soon the gravity gun from HL2... Soon.

Why do you all have to assume you're right? Can't you assume it would work, and try to figure out how, instead of putting the guy down? I think it sounds like a quite plausible idea, depending on how bright you want your light.

Why do you all have to assume that he doesn't have a plausible idea? Can't you assume it would work and try to figure out how, instead of putting the guy down bc you didn't win any awards? I think it's quite a plausible idea, depending on how much light you want. (even though I detest tree-huggers, your attitudes are disgusting)

oops... I guess I wasn't patient enough.

"(Please be patient, it may take a moment for your comment to appear.)"

Ritsak, they just did some simple physics to calculate precisely how much energy you can extract from the gravitational potential of that weight lifted that distance, and hence how much light you can get out of it.

If the inventor managed to beat the laws of physics, he'd have something a lot more exciting than en economic lamp to show for it...

Maybe he has some hyper-efficient LEDs, or some part of that calculation that I'm too lazy to check was actually wrong (you'd assume the guy would do such calculations) so I'm happy to be proven wrong, but don't jump on them for being skeptical - without skeptics we'd be trying to get cheap energy by imploring the Sun God to shine harder.

Hey, Ritsak. I have an investment opportunity for you. You will make millions of dollars, guaranteed. Please send me $1000 and I will give you this amazing secret.

Oh, and please don't engage your logic, that would be a disgusting attitude. Just assume this will work.

I'm sure it will last 200 years. I have a device that works on the same principle--it's a pendulum clock. I crank up the weights once a week and it keeps time 24x7. It is over 200 years old.

If 18th century technology can last 200 years, I think 21st century technology has a good shot

I'm not going to pretend to know what calculations are needed to develop a device that polarizes a forum with such polarity but what if the inventor figured out some way to create more resistance for the weight, generating more kinetic energy? Just a thought. Or maybe the weight houses a colony of "space worms". You know, those little critters that eat air and produce enough energy in their waste to power starships. Not only would the "space worms" create a renewable source of energy but also a renewable source of amusement. Those silly "space worms". They crack me up.

Check it. http://www.core77.com/competitions/greenergadgets/projects/4306/greener_gadgets_03.jpg

Two seconds on google yielded more details and this nice schematic that explains the mechanics of the machine in a way that I think even Dinoroger.. alright, maybe not. But for the rest of you.

@ROSSGRADY: Thank you! I came here to say the same thing; power required for this device isn't just gravity; it's "powered" by the force that sets the potential energy of the weight back into position to become kinetic energy. Maybe that's why this article is at "SciFi" instead for "PopSci" or "SciAm"...

Yea probably the same amount of energy it takes for your fat azz to either put down the whopper and get off the couch to flick the light switch or move your gigantic fat arms fast enough to clap twice for your clapper.

IF MADE IN CHINA IT WILL LAST A YEAR BUT THIS IS GOOD FOR THE PROFIT MARGIN.

PUTTPUTT JUDGES THIS A HIT.

Just a laymans thought... having looked at the web page with the diagram, why bother including a recitfyer when you could wire up the LEDs like a full wave rectifier and let them do it themselves while giving out light? Other than that, seems like a good idea if you live off grid and can still afford it... I have several wind up torches that I keep in my cars.. At least the torches are green! (ish) :-)

One other thought... it's bloody ugly! When will people start making things with a bit of taste again like they used to a hundred hears ago? My house is full of antiques, it just wouldn't go!

"DinoRoger . . . do you have to wear a helmet when you use the internet?

Why couldn't it have ten weights, and be a limitless supply of free energy? We could hook the whole grid up to it!"

MY GOD!! That is the funniest thing I've ever read on the internet. I seriously couldn't stop laughing, I fell out of my chair, actually cried a little bit, I don't know why, it's friggin hilarious, I still can't stop laughing...By A Clue - Thank you so much, you have made my week, possibly even the month or year. Man that's funny!!

I have a brilliant Idea... For light during the day, we could use a sunlight, and
at night we could sleep! (everyones scheduals would have to change so that the sun would be at the right time...) but hey, 100% efficiency!

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