http://www.vtnews.vt.edu/story.php?relyear=2008&itemno=111

Quote :

"Lamp lit by gravity wins Greener Gadget award By Susan Trulove Gravia lamp BLACKSBURG, Va., February 19, 2008 -- A Virginia Tech student has created a floor lamp powered by gravity. Clay Moulton of Springfield, Va., who received his master of science degree in architecture (concentration in industrial design) from the College of Architecture and Urban Studies in 2007, created the lamp when he was an industrial design graduate student. The light-emitting diode (LED) lamp, named Gravia, has just won second place in the Greener Gadgets Design Competition as part of the Greener Gadgets Conference in New York City. Concept illustrations of Gravia depict an acrylic column a little over four feet high. The entire column glows when activated. The electricity is generated by the slow fall of a mass that spins a rotor. The resulting energy powers 10 high-output LEDs that fire into the acrylic lens, creating a diffuse light. The operation is silent and the housing is elegant and cord free -- completely independent of electrical infrastructure. The light output will be 600-800 lumens - roughly equal to a 40-watt incandescent bulb over a period of four hours. 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. The sled begins its gentle glide back down and, within a few seconds, the LEDs come on and light the lamp, Moulton said. "It's more complicated than flipping a switch but can be an acceptable, even enjoyable routine, like winding a beautiful clock or making good coffee," he said. 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." He predicted that the acrylic will begin to yellow within 10 to 15 years when Gravia is used in a home's interior room. A patent is pending on the Gravia. To learn more, contact Jackie Reed of Virginia Tech Intellectual Properties Inc. (http://www.vtip.org) at jreed@vtip.org or call (540) 443-9217. Learn more about the lamp and the designer's philosophy at http://www.core77.com/competitions/greenergadgets/projects/4306/"

2/21/2008 7:58:54 AM

INNOVATION IN ACTION

2/21/2008 8:33:32 AM

omg, what will they think of next. Gravity powered clocks!?

oh wait

2/21/2008 8:33:48 AM

second place is no place!

2/21/2008 9:07:12 AM

I mean, that's exactly what I thought of when I read the title...

weight + damping + magnet + LED's

the clock thing is exactly right... welcome to several hundreded years ago and combining it with 10y/o technology...

but then again... hasn't been done like this before so good job him...

2/21/2008 9:24:28 AM

Yeah... i am not impressed... and its not gravity powered its people powered.. you move the weights and give the thing its potential energy.

If we made gravity powered stuff it would be free energy that came from nothing.

2/21/2008 9:43:22 AM

well, while it's not "new"...as mentioned above, it hasn't been done before, so his ingenuity is at least better than ours, since we didn't do it

2/21/2008 9:51:47 AM

Sure it's been done before. I have a wind up LED flashlight right now.

2/21/2008 9:56:18 AM

It hasn't been done with that sort of style before, you are correct... but it has been done.

2/21/2008 10:08:25 AM

This reminded me of a madtv skit:

2/21/2008 10:12:09 AM

I read yesterday that The Sharper Image is filing for bankruptcy.

Alas, where will he sell this marvelous yet overpriced invention?

2/21/2008 10:12:17 AM

Not to mention, since it uses banks of LEDs, you get a "diffuse light" source equivalent to a 40-watt bulb.
…. so maybe it's enough to put in a corner and get some soft light, but hardly enough to light a room.

2/21/2008 10:13:46 AM

"i sure do post in message boards way better than this guy invents stuff"

2/21/2008 11:13:41 AM

Dude i design environmentally friendly stuff daily... its my friggin job

2/21/2008 11:16:54 AM

congratulations. but really i don't see how belittling a person for making an environmentally friendly product - as a student project no less - is necessary here. yes, he took an old technology and applied it to lights. why is that lame? sure, it's not going to replace all the lamps in my house but it is a step in the right direction.

2/21/2008 11:45:39 AM

it's not lame, but it begs the question: why was it posted here?

As you know, Tech Talk is serious business and we can't get on with our serious business if we have to mull through all the riff-raff!

2/21/2008 11:55:16 AM

Maybe the OP thought it was interesting and considered that others might as well. If you disagree, that's fine, but don't crap the thread, this is much more interesting than half of the threads on the first page of tech talk.

2/21/2008 12:05:57 PM

ok, i'll say this much: i think it is cool for a student project, and a novel application.

but I hate press releases and articles that take generally known ideas and try to present them as something new. I don't see, for example, how they could get through a whole press release on that lamp without writing something to the effect of "it works on the same principle as a grandfather clock". To pretend like this is a new technique to power anything is intellectually dishonest

2/21/2008 12:11:16 PM

nowhere in the article does it say this is a "new technique".

in addition:

Quote :

"The precedent for this lamp lies within horology—the science of keeping time. Gravia recalls the archetypes of 'grandfather clock', 'hourglass' and 'wind-up clock'. User input provides the potential energy for these devices, and maintains a cycle of timely upkeep for the life of the object."

which is from http://www.core77.com/competitions/greenergadgets/projects/4306/, a link that was provided in the OP and the article.

2/21/2008 12:17:27 PM

A lot of you guys sound like jealous little school girls. It's a neat design project and it's non-trivial to go from one of those flashlights you jerk off for a few seconds to get a minute of light or so to something that is conceivably useful as room lighting. Sure it's no reading lamp, but it's enough to get around you living room or leave on for when you have to take that 2 am piss without worrying about the electric bill. Granted it doesn't deserve the attention its recieved on digg and engadget, but damn you people sound bitter.

2/21/2008 12:18:49 PM

(heh, that implies that we actually READ the tech articals further than what's spoon fed to us in the thread...)

I for one didn't

2/21/2008 12:19:07 PM

Chalk that up to shallow reporting from the VT school newspaper. I know we'd like to hold all school papers to the standards of our own technician, but hey they can't all be pure gold.

[Edited on February 21, 2008 at 12:21 PM. Reason : ]

2/21/2008 12:21:22 PM

it's using gravity to power an LED that's equivalent to a 40-watt light bulb for 8-hours....

that's free energy being harnessed, i for one think it's brilliant, and i'm sure can be used for many more uses.

2/21/2008 1:47:39 PM

i think its interesting and a neat little project.

2/21/2008 1:58:54 PM

Quote :

"it's using gravity to power an LED that's equivalent to a 40-watt light bulb for 8-hours.... that's free energy being harnessed"

not to nitpick (ok, yes, to nitpick), gravity is not the free energy that's being used here. As someone else pointed out, the energy source is in the lifting of the weight. So technically, the fuel-input is whatever amount of work that a person must do to lift the x-kg weight x-meters. This energy is likely negligible, as it wouldn't exactly require a person to fuel-up on high-calorie food to lift up that weight a few feet every 4 hours. It's also negligible considering the amount of energy required to run incandescent bulbs - remember when you were a kid and you went to the science museum, and they always had the exercise-bike hooked up to electric appliances like light bulbs and hair dryers? It took a LOT of energy to run that bike to power those bulbs (although those bikes weren't exactly models of high-efficiency power generation).

To expand on this project, though, I think a fun spin-off of this concept would be to hook the lamp up to electricity, but have electricity drive a motor to lift the weight, not to power the bulb. Just take a small DC motor and adjust the gearing or use some pullys to lift the weight. When the lamp was turned on, every 4-hours the weight would fall to the bottom, trip a switch which would activate the motor, which would raise the weight in about 10 seconds, then it would turn off automatically. That way, it would basically work like a traditional lamp (i.e. no manual labor apart from flipping a switch like normal) but would only use 10 seconds of electricity for every 4 hours of (dim, diffuse) light produced.

[Edited on February 21, 2008 at 2:16 PM. Reason : .]

2/21/2008 2:15:38 PM

Yeah I was thinking the same thing..

2/21/2008 2:22:03 PM

yeah, the more I think about it, even if the light was kind of dim or non-directional, i would totally buy a couple if it used the motor method

2/21/2008 2:27:40 PM

I'd like the motor idea if it was somewhat optional -- that is, if you can disable the motor and be capable of flipping it by hand if you so desired.
For houses in bad-weather areas (snowy, icy areas, hurricane areas), this is a fantastic solution for when there are weather-induced electricity failures. It'd be nice to be able to activate these instead of having to deal with flashlights and candles whenever there's an ice storm.

But more on the motor idea... Thermodynamically [Conservation of Energy] speaking, would there be any actual power savings here? Would moving the weight back up to the top of the tower use just as much (or more) energy than running the LEDs for the duration of the charge?

2/21/2008 11:16:23 PM

Quote :

"To expand on this project, though, I think a fun spin-off of this concept would be to hook the lamp up to electricity, but have electricity drive a motor to lift the weight, not to power the bulb. Just take a small DC motor and adjust the gearing or use some pullys to lift the weight. When the lamp was turned on, every 4-hours the weight would fall to the bottom, trip a switch which would activate the motor, which would raise the weight in about 10 seconds, then it would turn off automatically. That way, it would basically work like a traditional lamp (i.e. no manual labor apart from flipping a switch like normal) but would only use 10 seconds of electricity for every 4 hours of (dim, diffuse) light produced."

would defeat the whole purpose of the lamp

2/21/2008 11:19:11 PM

how much does it cost me to pick something up...
how much money does it cost me to power an incandescent bulb...

exactly. it's free.

in no way did i mean that it somehow broke the laws of thermodynamics.

2/21/2008 11:20:17 PM

shit, I'm not getting up every 4 hours to "recharge" it. Fuck that. I'd just game in the dark...

2/22/2008 12:01:09 AM

a lot of ignorant jealous schmucks in this thread.

"not impressed because I can't do it myself"

2/22/2008 12:20:12 AM

could you possibly integrate air pressure?

like when it is falling it builds air pressure to a certain point, at that point a valve would release the built air thus sending the weight back to the top and then shutting the valve off again and starting the thing all over

im not sure how it would be able to fall yet build enough pressure...but i feel like its a viable option some type of release or suction capability?

nothing? prolly not feasible

2/22/2008 12:28:48 AM

I give him props for doing it, the styling is nice but as stated before it's kinda pointless if the operator has to reset the weights. Incorporating a natural supply would be best, though hydraulics or wind power would be hard for an indoor light. Maybe something like those opaque-covered solar panels built into the supports that could recharge some li-poly or li-ion batts whenever the small reset motor needed to be reset. All it would need is a room with a window to be self-reliant for a good while, at least until the batts needed to be replaced a couple months or years later. But I guess that would conflict with his greener philosophy. Ah, I'm just rambling, I've always thought of doing something like this but using magnets instead of weights and going from there.

2/22/2008 1:00:53 AM

^So by your logic, grandfather clocks are pointless?

I think it would be neat to have in a power outage if you are too lazy to find candles, matches or a flashlight...in other words if you are too stupid to find that stuff before the storm puts out the power.

2/22/2008 5:30:33 AM

Quote :

" like when it is falling it builds air pressure to a certain point, at that point a valve would release the built air thus sending the weight back to the top and then shutting the valve off again and starting the thing all over"

that would be a perpetual motion machine, and therefore impossible.

Quote :

"But more on the motor idea... Thermodynamically [Conservation of Energy] speaking, would there be any actual power savings here? Would moving the weight back up to the top of the tower use just as much (or more) energy than running the LEDs for the duration of the charge?"

yeah, that's true. after friction, of course it would take more power from the motor to lift the weight than power that would be generated from its fall. So it would be more efficient from a power usage perspective to just plug the led lamp into the wall (via an AC-DC converter) and run it directly, which would of course still be much more efficient than an incandescent. However, it would still always have the option of manual operation or operation when the power is out. just like any battery or crank powered light or radio, except hopefully more convenient.

2/22/2008 7:51:41 AM

lol at anyone complaining about lifting something up every 4 hours

[Edited on February 22, 2008 at 7:56 AM. Reason : ]

2/22/2008 7:56:35 AM

2/22/2008 9:34:29 AM

im serious, are people that lazy?

2/22/2008 9:53:36 AM

to get light into a house? umm, yeah, they are.
The status quo for decades now is to flip a switch and get instant light. If you told someone that they could save $2 a month on their power bill by replacing all their existing floor lamps with a "gravity lamp" where they have to reset a weight for every 4-hours of use, then yea - they would laugh at you.

to make something like this gain traction (not implying that is the point of this lamp, at this point it just seems like a proof-of-concept and a nice idea), it would need to improve in several ways
1) increase the light output, or make it adjustable
2) make it switchable, so you could, just like today, "flip a switch" and it would turn on. In this case, the switch would just stop and start the weight from dropping.
3) make it turn on instantly when the flip is switched, just like today's lights. maybe it does this already, though
4) Most importantly, increase the amount of time between "recharges". If it could run for, say, 30 hours without recharging, and you use it an average of 5 hours a day (say its on all evening between work and bedtime), then you would get almost a week's use out of it before resetting the weight. Something like that could gain mass-appeal, i think.

2/22/2008 10:03:45 AM

This is America, do you even have to ask? We invent stuff to do less work for us, not create more work...

[Edited on February 22, 2008 at 10:06 AM. Reason : work = bad]

2/22/2008 10:06:19 AM

^^ well obviously this is an initial design, and thus given the amount of light output i wouldnt see anyone using this as a regular light that you would be turning on and off frequently until it improved.

but even then, say you were able to get this to provide adequate lighting for an entire room for 4 hours, only having to lift the light once. i am one to turn off lights when i enter/leave a room. sure that is literally no work at all. but if people are doing that several times over 4 hours in my place, having to only do that once would work quite nice, even if it required you to lift a weight instead of flip a switch.

Quote :

"2) make it switchable, so you could, just like today, "flip a switch" and it would turn on. In this case, the switch would just stop and start the weight from dropping. 3) make it turn on instantly when the flip is switched, just like today's lights. maybe it does this already, though"

i think both of these would require electricity and thus negate the usefulness of this light. it is also a nice idea for some light in areas with power outages like others have said. i think the other things are definitely things that any of us would like to see improved before this is very useful for normal use.

2/22/2008 10:25:11 AM

no, #2 ("make it switchable") doesn't necessarily require electricity. It doesn't necessarily have to be switchable by a wall-switch, i mean a knob or switch on the lamp itself, just like most end-table and halogen lamps are switched on the lamp itself, not though the wall. It would be a mechanical switch that would simply stop or start the weight from moving ("off" would just be a ratchet or clamp to hold the weight in place, "on" would just allow it to fall like normal)

and about #3, i guess that just depends on how it actually works. maybe within a second or two of the weight going into controlled free-fall enough power is generated to activate the LEDs.

2/22/2008 10:44:37 AM

there is so much fucking stupid in this thread

2/22/2008 11:08:37 AM

^^ sorry i was thinking back to when you said:

Quote :

"To expand on this project, though, I think a fun spin-off of this concept would be to hook the lamp up to electricity, but have electricity drive a motor to lift the weight, not to power the bulb. Just take a small DC motor and adjust the gearing or use some pullys to lift the weight. When the lamp was turned on, every 4-hours the weight would fall to the bottom, trip a switch which would activate the motor, which would raise the weight in about 10 seconds, then it would turn off automatically. That way, it would basically work like a traditional lamp (i.e. no manual labor apart from flipping a switch like normal) but would only use 10 seconds of electricity for every 4 hours of (dim, diffuse) light produced."

so i just assumed you were still referring to that and that you could just control the position of the weight that way. so that was just a misinterpretation by me. I didnt know that you were talking about a mechanical switch as opposed to an electrical one in your later post.

2/22/2008 11:27:30 AM

i am not normally one to say RTFA but...

Quote :

"The sled begins its gentle glide back down and, within a few seconds, the LEDs come on and light the lamp"

and seriously, how often are you in the same room long enough to need to leave the light on for more than 4 hours at a time? i hardly use any lights at all during the day. yes this would be impractical in its current form for a quick trip to the bathroom, but to add some light to a dark corner for 4 hours just by walking over and picking something up is not much to ask.

but yes, agentlion's step #4 is IMO the best way to improve this. unfortunately i don't see how until that motor is greatly improved. they can't just increase resistance and add weight - it already uses 50lbs. of weights to get those 4 hours, which makes it impractical or impossible for children, the elderly, super lazy people, etc. to use. if they could double the time and cut the weight in half, it would be much better off.

2/22/2008 11:35:16 AM

There isn't much sense in discussing design optimizations. This whole thing is really embarrassing for VT considering they have an engineering program .. unless he's broken the laws of physics, his calculations are completely bunk. He has never built the thing nor will he ever unless he figures out a way to get a couple tons of weight in the thing to make it work.

50lbs = 22.67Kg
58in = 1.47m
4hrs = 14400s

The potential gravitational energy in joules would be 22.67 * 9.8 * 1.47 = 326.584J

Given that a joule is 1W/s so 327J = 327W/s .. span that over his 4 hour time and you're getting continuous output of 0.0227W. AND that's assuming 100% efficiency, which you won't get.

That's nowhere near enough to even power a single high-efficiency LED. Lets say that someone invents a LED that puts out 150 lumens/W (higher efficiency than what's currently available, I believe - the highest I've seen are like 100 lumens). You're still not going to be able to power the damn thing for more than a minute at a time. If you're pushing 600 lumens which was the low end of his power output, that would require 4W at least. 327 / 4 = 81.75 seconds. So with all of this, assuming 100% efficiency and an LED that doesn't exist, he could power light his lamp for a little over a minute.

To compute how much weight he would have to use (in a 100% efficient system):

4W over 4 hours = 57600J

x kgs * 9.8 * 1.47 = 57600J
x = 3998kg = 8800lbs

So I guess if you want to move over 4 tons of weight every 4 hours to get your 600 lumens of output, it's possible.

2/22/2008 12:35:35 PM

And yes I realize I'm taking a few liberties with these calculations but for all intents and purposes, they're good enough to debunk it.

2/22/2008 12:37:28 PM

i'm not an engineer so i don't really have much of a reason, but i find it hard to believe you. how can a hand crank radio be powered for 1 hour? how do those "shake it" flashlights work with such little effort?

2/22/2008 12:49:04 PM

the flashlights charge a capacitor inside by sliding a magnet in a coil that induces current that's stored in a cap that's slowly discharged. the hand crank radio is the same basic idea, its just using the rotational energy to generate energy. those hand crank devices don't work for stuff that requires a higher electrical draw. a hand crank radio only lasts a short time. as i stated, his light could work for a few minutes at a time.

2/22/2008 1:01:38 PM