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Gravity Lamp Grabs Green Prize

CmdrTaco posted more than 6 years ago | from the well-isn't-that-clever dept.


eldavojohn writes "A lamp powered by gravity has won the second prize at the Greener Gadgets Conference in NYC. From the article, "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 estimates that Gravia's mechanisms will last more than 200 years, if used eight hours a day, 365 days a year." The article contains links to the patents and the designer/inventor Clay Moulton's site." I think my laptop would require a slightly larger weight to pull this off.

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Looks cool... (1, Funny)

jellomizer (103300) | more than 6 years ago | (#22488682)

Where can you buy it and how much.

Re:Looks cool... (5, Funny)

edittard (805475) | more than 6 years ago | (#22488726)

Say what?!? Why on earth would they tell you that?

This is slashdot, we have articles here, not thinly disguised advertisements.

Obligatory (1)

PFI_Optix (936301) | more than 6 years ago | (#22489378)

You must be new here.

Next thing you know... (3, Funny)

clonan (64380) | more than 6 years ago | (#22488746)

you will have to start flipping your desktop over every few minutes ;-)

Re:Next thing you know... (2, Funny)

techpawn (969834) | more than 6 years ago | (#22488886)

you will have to start flipping your desktop
I had my boss convinced he had do do that with his green powered etch-a-sketch laptop

Re:Looks cool... (4, Interesting)

eln (21727) | more than 6 years ago | (#22488842)

I really like the idea, and would probably buy one if the price is right.

However, one thing concerns me. The weights are moved up to the top by human power, which is fine, but according to the picture on the designer's website, the weights are 5 10 pound weights in each lamp, so either I'm having to lift 10 pounds 5 times every time I want to light the lamp, or I'm lifting 50 pounds. Perhaps he could incorporate some sort of foot pedal mechanism or something to more easily lift the weights. If he could figure out how to do that, and also maybe improve the efficiency a little more to get more than the 40-watt equivalent it gets now, I could see this becoming a solid replacement for traditional lamps.

Re:Looks cool... (5, Funny)

Angostura (703910) | more than 6 years ago | (#22488998)

Perhaps he could incorporate some sort of foot pedal mechanism or something to more easily lift the weights.

I can't really see why a small electric motor couldn't be incorporated into the design to do this, surely it would be much more convenient?

Re:Looks cool... (-1, Redundant)

qoncept (599709) | more than 6 years ago | (#22489366)

Apparantly you're ignoring conservation of energy. If you're powering an electric motor to raise (or increase the potential energy of) the weight, with the added step, you're decreasing efficiency and using more electricity than you would if you had just plugged in a lamp.

Re:Looks cool... (2, Funny)

GenP (686381) | more than 6 years ago | (#22489086)

So it's like racking a 50 pound dumbbell from the floor. Piece of cake.

Re:Looks cool... (1)

TheLostSamurai (1051736) | more than 6 years ago | (#22489186)

Why not use a pulley? You could simply add something to the back of the lamp that you exert the weight of your body on to lift the weights. (Assuming you way more than 50 pounds and the lamp could somehow be stabilized)

Re:Looks cool... (2, Interesting)

eln (21727) | more than 6 years ago | (#22489286)

A pulley would probably be the most efficient way, but I suggested a foot pedal because I was concerned a pulley system would interfere with the overall aesthetics of the device. Either way, though, as long as you can make it easy to lift the weights without making the lamp look terrible, I think the idea is a good one.

Re:Looks cool... (5, Interesting)

TheLostSamurai (1051736) | more than 6 years ago | (#22488944)

"Concept illustrations of Gravia" "Moulton estimates" "He predicted"
As far as I can tell this is nothing more than vaporware. There doesn't seem to be any indication in the article that this thing has actually been built. While is does seem like a cool concept the overall implementation does not seem that complicated; so why has he not actually built the thing?

Re:Looks cool... (1)

T-Bone-T (1048702) | more than 6 years ago | (#22489060)

It isn't even vaporware. It has to be a product, not just a concept, to be vaporware.

It can't possibly work either (5, Informative)

Maddog Batty (112434) | more than 6 years ago | (#22489228)

22.6 Kg x 1m x 9.8 m/s^2 / 4 hours = 0.015W if conversion is 100% efficient (which it won't be)

The red led on the front of your modem requires around this amount so the glow will be feable. To get the equivalent of a filament 40W bulb requires around 10W so the system is only around a factor of 1000 out.

It's nice to see good news from Virginia Tech (-1)

yog (19073) | more than 6 years ago | (#22489036)

After the massacre last year, Virginia Tech became just another descriptor for massacre, like Columbine or Kent State. Now along comes this beautiful, brilliant invention that captures the imagination. It made my day to read this report, and like probably 90% of the people who read it, I want one! Maybe the student can set up a company, become rich, and perhaps he'll dedicate some fraction of the proceeds to the families of those slain. I'd pay a few dollars extra for that, no problem.

Along these lines, maybe someone can invent a way to power the porch light from opening and closing the door. There's probably a hundred ways we can harness excess energy in our homes--opening and closing cabinets, exercising on a treadmill or elliptical, etc. Hook a gizmo up to the TV so that you have to lift 25 pounds to pay for 30 minutes of viewing--earn your right to be a couch potato :)

Home Gym.. (1)

bigattichouse (527527) | more than 6 years ago | (#22488756)

how long before the home gym captures energy for your home. (pre-patented by the professor on gilligan's). Also, where the hell do I buy one?

Re:Home Gym.. (1)

jessiej (1019654) | more than 6 years ago | (#22488778)

Yeah, I'm wondering how heavy the weights are, would grandma be able to use it?

Re:Home Gym.. (1)

aseidl (656884) | more than 6 years ago | (#22489248)

With a system of pulleys?

Re:Home Gym.. (5, Insightful)

krlynch (158571) | more than 6 years ago | (#22489030)

how long before the home gym captures energy for your home.

Never :-)

Humans can not produce large amounts of sustained output power, even when exercising. A "healthy human" can probably push out 300W for about 20 minutes [] before they collapse from exhaustion. Even if you can convert all of that to electricity and store it for later use at something like 50% efficiency (which would be staggeringly high), you're only talking about 0.05kWh of usable energy. You could do much better if you were willing to exercise at much lower intensity for much much longer periods of time (but who would do that just to light a minuscule handful of light bulbs). But you're really not going to ever get usable amounts of power out of your daily exercise routine.

Re:Home Gym.. (1)

dintech (998802) | more than 6 years ago | (#22489190)

You're not thinking big enough. []

Re:Home Gym.. (2, Informative)

antifoidulus (807088) | more than 6 years ago | (#22489292)

Ride a bike instead of driving.

What's next for gravity power? (5, Funny)

friedo (112163) | more than 6 years ago | (#22488760)

How about a clock?

gravity powered? (3, Informative)

airdrummer (547536) | more than 6 years ago | (#22488824)

seems to me the potential energy comes from your muscles;-)

Re:gravity powered? (1)

Thanshin (1188877) | more than 6 years ago | (#22488906)

seems to me the potential energy comes from your muscles;-)
You, sir, are the sublimation of subtlety.

Re:gravity powered? (3, Funny)

BattleApple (956701) | more than 6 years ago | (#22489032)

So basically, this thing runs on pizza, pop tarts, coffee, mountain dew, and beer?

Re:gravity powered? (1)

HappySmileMan (1088123) | more than 6 years ago | (#22489316)

Yean but it's easier to power if you stay away from pop tarts and beer

Re:What's next for gravity power? (1)

manifoldronin (827401) | more than 6 years ago | (#22489074)

How about a clock?
Sure, better yet, an alarm clock that goes off to remind you to lift the weights!

A patent? (2, Insightful)

Trailer Trash (60756) | more than 6 years ago | (#22488766)

How is this any different than a clock powered by weights? It's nice, but hardly a new idea.

Re:A patent? (5, Funny)

Anonymous Coward | more than 6 years ago | (#22488822)

You don't know the difference between a lamp and a clock?

One tells time, the other emits light. I thought that was fairly obvious.

Re:A patent? (5, Funny)

aztektum (170569) | more than 6 years ago | (#22488834)

Duh! Because it's a *light* powered by weights!

Re:A patent? (2, Informative)

the grace of R'hllor (530051) | more than 6 years ago | (#22488836)

It translates mechanical motion into light (rather than redirecting the mechanical energy) in a practical self-contained manner. I haven't seen any mechanically powered home lighting yet.

Re:A patent? (2, Funny)

gardyloo (512791) | more than 6 years ago | (#22488914)

My gerbils take offense to this. (No Richard Gere jokes, please)

Re:A patent? (1)

MrShaggy (683273) | more than 6 years ago | (#22489120)

How do you think we get power? Its all mechanical.

All you are doing is translating the power from the water, (Niagara Falls, Hoover Dam), and turning it into something that you can use at your house.

Even Nuclear and coal, use water, in the form of steam, to turn the generators.
Whole lot of mechanical energy there. I think only form of non-mechanical energy would be solar. Even wind is based on the motion of the ocean.

Re:A patent? (1)

WiglyWorm (1139035) | more than 6 years ago | (#22488874)

Clocks powered by weights don't run on electricity. Lights powered by weights still do. It may not be new, but generating an efficient, bright, long lasting light source from the energy generated by a falling weight is not even in the same category as generating motion in a clock through a falling object.

Re:A patent? (1)

Bartab (233395) | more than 6 years ago | (#22488908)

A "gravity powered clock" uses the weights as mechanical energy to power the timing mechanism, the same as a wound spring. This light is converting it to electricity due to the lack of a flywheel light source. So basically to answer your question, the new part is converting the power into an electrical source. Without that, the number of uses for such a gravity/weight system to do useful things is limited.

My mother happens to be a retired clockmaker. Likely one of the last. I've never lived in a house without a grandfather clock.

Re:A patent? (1)

Trailer Trash (60756) | more than 6 years ago | (#22489026)

Dude, I understand how a weighted clock works (the weights don't just power the timing mechanism, they powers the clock, sometimes with different weight sets to power the chimes), but, I'm sorry, this just isn't that different. It's like seeing the various patents for doing obvious things, but "on the internet". Using weights to provide power is a *very* old concept, and that's all this is.

Re:A patent? (1)

sir_eccles (1235902) | more than 6 years ago | (#22489290)

I'm going to refrain calling you an idiot. Clearly the fact that Home Depot is full of these and similar devices illustrates how incredibly obvious this idea is. Looking at the pictures of the device I would guess the inventiveness is in making the weight drop down the ball screw in a controlled manner over 4 hours. Very different from a clock weight dropping. If there really was a link to the patent, that would really help, but then again when has a story summary been accurate.

Re:A patent? (1)

ILuvRamen (1026668) | more than 6 years ago | (#22489092)

because this one's powered by gravity, oooooh! And since that's incorrect, and you're incorrect, I feel the need to point out that it's powered by humans. The effect is just delayed. The weights don't power it and gravity doesn't power it. You're the one who uses energy to power it.

Re:A patent? (1)

GauteL (29207) | more than 6 years ago | (#22489196)

"How is this any different than a clock powered by weights? It's nice, but hardly a new idea."

By your standards the cigarette lighter was not innovative in it's time because people could already create fire by using pieces of flint manually over a pile of grass. The cigarette lighter, however, was much more suitable an object to carry around in your pocket for lighting your cancer sticks.

In the same way, the method this lamp captures energy may be very different from a clock pendulum in ways which is far more suitable for creating a lamp.

bwahaha. (5, Funny)

notgm (1069012) | more than 6 years ago | (#22488776)

i'm going to use the light from this lamp to power my photovoltaic weight lifting machine.

Re:bwahaha. (1)

The-Bus (138060) | more than 6 years ago | (#22489008)

And here I was using a coal-powered mechano-arm to move the weight back up to its original position.

Re:bwahaha. (4, Funny)

nicklott (533496) | more than 6 years ago | (#22489204)

In this house, we obey the laws of thermodynamics!

But who is going to control (5, Funny)

joeflies (529536) | more than 6 years ago | (#22488794)

the consumption of gravity? Just imagine the peril if we use our precious resources like gravity on things like lamps, when we have coal to burn.

Will it still be cool to light up your lamp with gravity, when there's no gravity left and people are spinning right off the planet into outerspace? I guess it will eliminate the greenhouse gas issue by allowing the atmosphere to disappear when there's no more gravity left - but unfortunately it will also not allow people to live (the ones that are still on the planet after the other ones spun off into space as noted earlier)

Re:But who is going to control (2, Funny)

jagilbertvt (447707) | more than 6 years ago | (#22489112)

While the parent is joking, I do wonder how much angular velocity the Earth would lose if we switched an entire country (or say the entire world) lights to being powered by such devices. Eventually the earth would stop spinning.. Has the inventor taken this into account? Perhaps he'll be to blame for the end of world!

Re:But who is going to control (2, Interesting)

NC-17 (411446) | more than 6 years ago | (#22489306)

Actually, we'd be OK. Just make sure there is another country on the other side of the world doing the same thing - they'll balance each other out!

Re:But who is going to control (1)

Thelasko (1196535) | more than 6 years ago | (#22489350)

Ever look into Gyrogenerators? [] So evil! Have to have one!

Peak Gravity (5, Funny)

Tteddo (543485) | more than 6 years ago | (#22488814)

But what will we do after peak gravity?

Re:Peak Gravity (0)

Anonymous Coward | more than 6 years ago | (#22488890)

After peak gravity, we'll just dig deeper holes, because gravity is stronger te lower you get. We will just have to remember to make the holes wide enough.

Way ahead of you buddy (5, Funny)

Sciros (986030) | more than 6 years ago | (#22488946)

I've already started looking into buying "gravity offsets" and trying to use as much rope, glue, velcro, and static cling as possible.

Bending Space-Time Lights the Way (5, Insightful)

MSTCrow5429 (642744) | more than 6 years ago | (#22488826)

"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.

Why would I buy a product that takes 10-15 years to become tolerable for normal household use, when in 10-15 years, either this technology will be updated so that it comes with natural light out of the box, or new competing technologies develop that do the same thing, without the color drawback?

Re:Bending Space-Time Lights the Way (1)

eln (21727) | more than 6 years ago | (#22488918)

I would imagine that just like CFLs before them, LEDs will eventually be capable of producing more natural light, even if it's only by way of a coating on the glass (or in this case acrylic) of the lamp. It does seem silly to wait 15 years for natural light, maybe he should look at tinting the acrylic and see what he can get from that.

Either way, it seems like maybe you wouldn't want to buy one of these things in their current state, but the idea has a lot of promise.

Re:Bending Space-Time Lights the Way (1)

somersault (912633) | more than 6 years ago | (#22489048)

I don't know about you, but I've always found yellowish indoor lighting annoying. I much prefer whiter or bluer hues. I bought a 'natural' lightbulb for my lamp once and the light to me seemed pretty bluish compared to my normal bulb. I then dropped the lamp by mistake and didn't bother to buy a new bulb. Oops.

Otherwise, why not just get a yellow lampshade?

Re:Bending Space-Time Lights the Way (1)

MSTCrow5429 (642744) | more than 6 years ago | (#22489244)

Otherwise, why not just get a yellow lampshade?
You'd need an unusually long, tubular lampshade.

I think I might actually like white/blue LED lighting, but I'd have to see it first in a domestic setting. It might only look cool in sci-fi and corporate settings. Right now, all my lighting are CFLs with light that looks almost exactly like normal incandescents.

Re:Bending Space-Time Lights the Way (1)

og_sh0x (520297) | more than 6 years ago | (#22489324)

I feel this device is mainly a thought provoking work of art. They're trying to sell you on the fact that this work of art will also get better with age like cheese or a grandfather clock, as supported by the fact that moving the weight every day is supposed to be fun, like winding a grandfather clock or making a pot of coffee.

!perpetual motion machine (2, Informative)

SailorSpork (1080153) | more than 6 years ago | (#22488828)

I had hoped that "using gravity" would be sort of a cheat to get around making a perpetual motion device, but in reality it's powered by a human moving the weight. Instead, its just another clever way to capture gravity that still needs substantial human assistance, similar to a pendulum.

Re:!perpetual motion machine (1)

bkr1_2k (237627) | more than 6 years ago | (#22489146)

Yes it still needs human assistance, but that doesn't negate the fact that it provides 4 hours of light with no external power source required. That's pretty impressive, and can probably be improved somewhat if someone bothers to continue refining the design.

I'm actually pretty excited about making one (since it doesn't look like you can buy them yet) though I think I'd consider using glass instead of acrylic and possibly try adding some mirroring to help amplify the light somewhat. There may be some mirrors in the design already, I couldn't tell from the quick glance at the design drawings.

I total misread that (2, Funny)

techpawn (969834) | more than 6 years ago | (#22488844)

I read it as:

Gravy lamp grabs green prize
But the gravity lamp makes much more sense. But I'm not sure it would catch on. It's like those flashlights you have to shake to make work. Yeah, they're neat, but people are lazy and just want to press a button and have it work. They don't want the effort of shaking it or moving weights around.

Re:I total misread that (1)

Spudtrooper (1073512) | more than 6 years ago | (#22489322)

mmmm...gravy lamp...aghghghghhggh

Bigger Weight? (1)

LoneWlf794 (984089) | more than 6 years ago | (#22488862)

I think my laptop would require a slightly larger weight to pull this off.
Of course I didn't RTFA, but I assume that as the weight is descending some sort of friction is being produced, which in turn produces your electrical charge. So wouldn't it make sense to have many smaller weights instead of one larger one?

Re:Bigger Weight? (2, Informative)

Bartab (233395) | more than 6 years ago | (#22488990)

You didn't read it.

That's not how the electricity is being generated, rather it is coming from a rotor system.

There would be no functional difference between one 50 pound weight and 5 10 pounds weight, other than in resetting the system.

Wouldn't it be more accurate... (3, Insightful)

Zebraheaded (1229302) | more than 6 years ago | (#22488872)

To say that it runs on potential energy? The device always *has* gravity, but it's not drawing it off. Once you supply the device with some potential energy though, it takes that energy and utilizes it.

I guess "Potentia" isn't as marketable a name, though.

Re:Wouldn't it be more accurate... (1)

residieu (577863) | more than 6 years ago | (#22489308)

It runs on potential energy, but it is gravitational potential energy. A battery powered lamp also runs on potential energy, chemical potential energy stored in the batteries.

Greener? Are we sure? (0)

Anonymous Coward | more than 6 years ago | (#22488892)

While on the surface it seems greener, it's really quite hard to tell. The light is powered by a falling mass, but the energy to lift the mass in the first place is provided by us. We get that energy from food.

So the real question: Is the end-to-end food energy process greener than the end-to-end electrical energy process?

Re:Greener? Are we sure? (1)

haystor (102186) | more than 6 years ago | (#22489054)

If that's not true, we could always build an electric motor to move the weight to the top. It could draw solar power...emitted by the lamp, of course.

Re:Greener? Are we sure? (1)

BigJClark (1226554) | more than 6 years ago | (#22489096)

Oh, I thought of that, as well as a contraption that exceeds the speed of light. I'm currently patenting the latter.

how long does it last between each "charge" (1)

TheAngryIntern (785323) | more than 6 years ago | (#22488926)

perhaps I missed it in the article, but does it say how long it lasts before you have to lift the weights again?

Re:how long does it last between each "charge" (1)

TheAngryIntern (785323) | more than 6 years ago | (#22488970)

nevermind, i read the article again and noticed the "over a period of 4 hrs"

Re:how long does it last between each "charge" (1)

bkr1_2k (237627) | more than 6 years ago | (#22489176)

The summary and the article both say 4 hours. It's a bit obscured by the " should last 200 years" comment though so not hard to miss.

Will not be seeing this on the (1)

bagboy (630125) | more than 6 years ago | (#22488930)

space shuttle any time soon, I guess.....

And it runs for four hours, too. (2, Informative)

Fantastic Lad (198284) | more than 6 years ago | (#22488948)

I don't know why this info was not included in the up-front literature. --It's only mentioned on the bottom left corner of one of the design graphics. []

Four hours is an awesome run-time for such a device.

I lived in a house once where the land lord had a wind-up radio. It was great in every respect other than its run time; every fifteen minutes or so you had to crank it up again, which made it annoying to use.


Re:And it runs for four hours, too. (2, Interesting)

Goaway (82658) | more than 6 years ago | (#22488994)

It would be pretty awesome, if it was possible.

The maths just don't check out, however. There is no way to produce that much light for four hours with anything less than a ton or so of weight.

Re:And it runs for four hours, too. (1)

HisMother (413313) | more than 6 years ago | (#22489408)

Care to show us your work?

Re:And it runs for four hours, too. (0)

Anonymous Coward | more than 6 years ago | (#22489412)

I think the key is that it's running on an LED (probably between 1W-5W), and *not* a 40W incandescent. Still though, I don't think the math checks out for even a 1W LED.

1W*4hrs*3600sec/hr= 14400J. Even assuming 100% efficiency, you've got to pull 1468kg (1.5tons) a vertical distance of 1 meter to get the energy required. . .

green? I don't think that word means what you... (2, Funny)

Anonymous Coward | more than 6 years ago | (#22488992)

...think it means. The human body has only about a 20% thermal efficiency. Add to this the ecological cost of transporting goods to the human for consumption, and you'll see where I'm going with this argument: what's touted as a "green" device actually costs the planet more per hour than any other light fixture ever invented.

So this idea may be useful in 3rd world countries where power grids are not available, but anyone with access to hydroelectric, wind, solar, coal, or nuclear power will actually be doing less damage to the planet by plugging the same light bulb into a wall receptacle.

End rant.

Re:green? I don't think that word means what you.. (2, Insightful)

FinestLittleSpace (719663) | more than 6 years ago | (#22489218)

"So this idea may be useful in 3rd world countries where power grids are not available."

Ranting for no good cause. That's EXACTLY where it is aimed at, anyway. May I also point out that lifting those weights is not going to produce signficant enegy usage that someone is going to have to change their diet in the richer parts of the world. Don't forget that one of the biggest problems in the wealthy world is OVER eating not undereating!

Next step ... (2, Interesting)

garett_spencley (193892) | more than 6 years ago | (#22488996)

Vibrating sex toys that power themselves ?

Re:Next step ... (4, Funny)

contraba55 (1217056) | more than 6 years ago | (#22489064)

All you'd need is one that ran on heat, assuming you're not into necrophilia.

Re:Next step ... (1)

HappySmileMan (1088123) | more than 6 years ago | (#22489434)

I am but I wouldn't use a sex toy on something that couldn't even enjoy it

Doesn't check out. (1)

Goaway (82658) | more than 6 years ago | (#22489018)

I think my laptop would require a slightly larger weight to pull this off.
Not just your laptop. This light itself would require quite a bit larger a weight to be able to do what it claims. There simply isn't all that much potential energy in a weight that will fit inside a lamp like that.

Re:Doesn't check out. (1)

Spectre (1685) | more than 6 years ago | (#22489178)

The lamp uses five 10lb weights ... are you quite sure that isn't enough, because it all checks out for me (this thing is NOT tiny).

Re:Doesn't check out. (1)

Goaway (82658) | more than 6 years ago | (#22489414)

Do the maths. It would require something on the order of tons to work.

Re:Doesn't check out. (0)

Anonymous Coward | more than 6 years ago | (#22489238)

It's 50 pounds.

Re:Doesn't check out. (1)

Goaway (82658) | more than 6 years ago | (#22489388)

Exactly. Far too little. We're talking tons here.

Re:Doesn't check out. (5, Informative)

retep (108840) | more than 6 years ago | (#22489370)

Yup, they say it emits 600-800 lumens.

Given that LEDs emit about 100 lumens/watt, that's say, 6 watts, * 4 hours = 86,400 joules They claim it's about 2m high.

Plugging those two values into the gravitational potential energy calculator at [] gives a weight of about 5000kg, slightly above the claimed 22kg...

Make it automatic! (1)

spacemky (236551) | more than 6 years ago | (#22489136)

Now someone will just have to invent a device which plugs in to an electrical outlet, which *lifts* the weight. That will eliminate the need for someone to do this manually. I'm checking the patent office now for prior inventions. Brilliant.

What in God's name is gravity? (1)

Malevolent Tester (1201209) | more than 6 years ago | (#22489140)

Is this some Darwinist scheme to try and tempt people away from Intelligent Falling?

bulbs (1)

alxkit (941262) | more than 6 years ago | (#22489156)

"The light output will be 600-800 lumens - roughly equal to a 40-watt incandescent bulb over a period of four hours."

A standard 40 Watt fluorescent light bulb emits about 900 lumens. This means that this new thing is about 2/3 as bright as regular, 40W bulb. Have you seen how dim 40W is? Now, make it 2/3 as bright... Wake me up when this invention glows as bright as the sun, because I would not spend a dollar on it. Maybe mole people might be interested.

Re:bulbs (0)

Anonymous Coward | more than 6 years ago | (#22489318)

This would be an incredible boon for people in developing countries if cheep to make/sell. Plenty of people just need/want enough to not smack their shins on things walking around.

Not everyone requires all lights in the house to be bright enough to read tiny print at all times.

Replace mood lights in the house with something that costs 0 to run, and turns itself off safely, and at a measurable time? hmmm.

oh yeah, but Slashdotters don't date do they..

weights aren't the best solution (1)

SethJohnson (112166) | more than 6 years ago | (#22489172)

As far as form-factor goes, this device is challenged by its risk of topheaviness. It requires a significant base to keep it from falling over. The weight could be replaced by a bunjie-cord and then it wouldn't have a tendency to fall over.

But the problem with a bunjie cord is that it's a consumable. It also requires significant energy to produce its elasticity. Which also brings up somewhat of a fallacy of this 'green' gravity lamp. The weights and other mechanisms of this lamp require significant energy to produce. The break-even on energy savings is probably realized only after many years of its use.


technically it's not "powered by gravity" (1)

v1 (525388) | more than 6 years ago | (#22489212)

You cannot extract power from gravity, but you CAN harvest the potential energy of two masses that are being attracted to each other BY gravity.

This is not a gravity-powered lamp, it's an "environmentally-conscious person moving weights"-powered lamp.

Calling it "gravity-powered" gives the less insightful the impression that it's free energy.

Set up their whole house this way. Put a big stack of 50 lb boxes in the basement, and tell them every evening when they come home from work to haul 30 of those boxes up to the attic and set them on the platform, all of which will be in the basement by this time tomorrow. Bet they change their mind about "free energy" right quick.

Though if you REALLY think about it, people complain about not getting enough exercise, AND complain about their electric bill, and this looks like a nice way to take care of two problems at once. It'd be interesting to try to compare the two monetarily - compare the average salary of someone that works at rent-a-center or U-haul, figure out how much he'd make moving that mass during the day, and compare that with how much of the electrical bill such a mass in a similar gadget could produce. Unfortunately, electricity is relatively cheap compared to labor, and I'd bet lighting up the dinosaurs is a lot more economical in the short run.

Supersize Me! (1)

arizwebfoot (1228544) | more than 6 years ago | (#22489232)

What about using the concept on a larger scale to power more "things" in the home. Everyone could have one in their back yard and each morning you turn it over and viola!, you can toast your buns on a cold day.

Gravity assisted battery? (1)

thePowerOfGrayskull (905905) | more than 6 years ago | (#22489246)

Sounds more like a gravity-assisted battery that stores the energy used to flip the weights. Still a cool idea, but saying that it's a "gravity powered lamp" is a bit inaccurate.

Doesn't pass muster (1)

EmagGeek (574360) | more than 6 years ago | (#22489272)

Assume: 12 Watts for 8 Hours/day, weight travels a vertical distance of 1 meter.


12 (J/s) * 1200 (s/day) * 365 (day/year) * 200 (year) = 1051.2 MJ

PE (J) = mgh = m (kg) * 9.81 (m / s**2) * 1 (m)

m = ~107 Mkg

Good luck with that...

Hmmm. What else falls around the house? (4, Interesting)

ScentCone (795499) | more than 6 years ago | (#22489326)

Got me thinking about how, in a two-story house, there's all sorts of vertical movement. I was picturing a way to step on a platform (sort of like those that parking lot attendants sometimes use) to ride from the second floor to the first. That buffered ride down could throw some energy into a flywheel. And, how about all of the greywater from upstairs? Three people taking their morning showers send many pounds of water down a vertical path to ground level. I wonder if passing that through some sort of screw drive might give up a few watts.

OK (1)

Quiet_Desperation (858215) | more than 6 years ago | (#22489334)

So now we just build one 200 feet tall, and an array of 5000 of them, and we eliminate out energy problems forever!

Build them in Kansas. They don't believe in gravity there anyway, so they won;t see them.

Please someone do the computations (0)

Anonymous Coward | more than 6 years ago | (#22489374)

I don't believe it, especially 600 lumens over 4 hours. Should be an easy computation for someone versed in physics:
(a) weight of 1 kilogram, height difference of 1 meter, what is the potential energy difference?
(b) how much energy used by LEDs to produce 600 lumen during 4 hours?
(c) how much kilograms needed to power these LEDs?


Energy Invested and Payback Period (0)

Anonymous Coward | more than 6 years ago | (#22489390)

How much energy do you think it takes to mine, smelt, cast and finish the 50 pounds worth of weights needed to power this thing. How about to create and assemble the drive shaft, generator, and extra housing for all if it. Then to ship it all that mass to the store and carry it home.

What do you think the payback period would be compared to just using the high-efficiency LEDs with a power cord?

A very interesting idea (1)

GauteL (29207) | more than 6 years ago | (#22489402)

It is not a concept which is going to revolutionise anything but neither the creator or the design committee claims that. It is much more of a niche item and something a fair few people would consider buying one of for the house as a design/fashion item (something most of us slashdotters probably doesn't understand). It is overall an innovative and interesting bit of industrial design which could well prove popular.

Is it worthy of a patent? Well, I'm always sceptical about patents in general, but the idea itself seem no worse than a lot of other patented designs.

Where does the energy come from? (1, Redundant)

gdr (107158) | more than 6 years ago | (#22489432)

Energy for 50lb weight (22.7 kg) dropping 4 ft (1.22 m), g = 9.8 m/s/s:

E = mgh = 271 J

Assume LEDs 100% efficient and standard lightbulb 2% efficient: 2% of 40W is 0.8W.

0.8W * 4 hrs * 3600 s/hr = 11520 J.

Have I made some horrible miscalculation or are they claiming over 4000% efficiency for this device.

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