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See the original image at vtnews.vt.edu

Lamp Lit by Gravity, Lasts 200 Years [Pic]

vtnews.vt.edu — Some Virginia Tech student (absolute genius) invented this energy saving, gravity powered lamp that can supposed last around 200 years emitting approximately 600-800 lumens.

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  • d00zt1n, on 02/21/2008, -9/+68Gravity light, will be very cool, hopefully it will be cheap
    • 1iProd, on 02/21/2008, -4/+123No way, gravity is very pricey nowadays.
    • kevir, on 02/21/2008, -4/+167I don't think you understand the gravity of the situation.
      • greenlight2001, on 02/21/2008, -1/+41By one look at your mom, I'd say gravity has it's hands full.
    • ChrisfromNL, on 02/21/2008, -6/+22With the price of gravity these days is it really that efficient?
    • jemka, on 02/21/2008, -2/+64Marty: Whoa, this is heavy.

      Doc: There's that word again, heavy. Why are things so heavy in the future. Is there a problem with the Earth's gravitational pull?
    • daborg, on 02/21/2008, -2/+50Typical of Digg to make light of a breakthrough like this.
      • thumperings, on 02/21/2008, -1/+1remember that story recently about the africans building solar panels to light their villages etc... this would be a much better idea for them. The cost of the broken batteries and broken replacment solar cells etc etc... The men of the village every night would just hoist up huge weights with a rope n pulley to run a gear system attached to dynamos ...no battteries necessary to light the LEd lighting I think it would be perfect and more cost effective.
      • nepawoods, on 02/21/2008, -2/+1It's not a breakthrough. It's an electric light. A lot of our electricity comes from gravity already - like hydroelectric, where the power comes from waterfalls. Same principle is used here. Not really a "lamp lit by gravity", in either case, of course.
        • daborg, on 02/21/2008, -1/+2I hear a sense of humor is on sale at Wal-Mart, you might want to look into it.
    • TheLastFreeMan, on 02/21/2008, -2/+24Not if Big Oil denies the existence of gravity like it did Global Warming.
    • blaze03, on 02/21/2008, -2/+13You're not very bright, are you?
      • ThndrShk2k, on 02/21/2008, -1/+5The light doesn't get very bright either.
        • thumperings, on 02/21/2008, -1/+1it woudl with boulders attached to dynamos .. woudl solve lighting in africa ..
    • SpittingUpWind, on 02/21/2008, -3/+6Awe man I thought they were talking about a Linux Server. Talk about up time.
    • TexMexMatt, on 02/21/2008, -6/+12Gravity is just a theory. Its God that is powering it. Burried as inaccurate. Should be Lamp lit by God.
    • TexMexMatt, on 02/21/2008, -11/+4Gravity is just a theory. Its God that is powering it.
    • danwallace, on 02/21/2008, -0/+4If only we could power a lamp with random commas.
    • TypeEE, on 02/21/2008, -0/+1On another story, the earth moves faster than ever towards the sun
    • glinsvad, on 02/21/2008, -0/+4Whats next? Gravity clocks - oh wait we have that
      http://en.wikipedia.org/wiki/Hourglass
    • Sharky35, on 02/21/2008, -0/+1I designed a powerplant that can power NYC... it runs on the random thoughts of a mouse named Sam.
      Now I am just waiting for a few advancements in technology and I'll be ready to go.
      You might see a prototype next year.
  • IanCal, on 02/21/2008, -39/+346Genuis? The guy can't even do basic physics.
    This thing has a 23kg weight, falling 4ft, which gives an output of 270J, assuming 100% efficiency (!)
    270J is 1W for just over 4 minutes. One watt for 600 lumens is also really, really generous. The best are in the region of 150 lumens/watt.
    "lasts 200 years" means the materials will last that long. Even using their calculations you have to lift a 23kg weight 4 ft every 4 hours.
    • Thuktun, on 02/21/2008, -26/+100"lasts 200 years" means the materials will last that long"

      In contrast with something using elaborate parts that wear out every year. Nobody was suggesting the device would produce light without attention for 200 years.
      • Falldog, on 02/21/2008, -4/+232To be fair the submission description makes it sound like the light will last for 200 years.
        • yunus, on 02/21/2008, -5/+7It will, you just have to have the space shuttle lift the weight for you next time it goes up.
          • dinostabOMG, on 02/21/2008, -3/+3The burning up in the atmosphere should provide you with enough light for now.
      • fireburner23, on 02/21/2008, -1/+13Then where the hell is my lamp that will produce light without attention for 200 years? When are we going to start producing all these cool things we hear on Digg all the time....wtf
        • Kral, on 02/21/2008, -0/+3You can get one, the only problem is it'd be radioactive. Tritium light sources go 10-20 years - pick something with a longer half-life and enjoy. Just don't break it. :)
      • Impact0115, on 02/21/2008, -12/+3http://digg.com/comics_animation/xkcd_Duty_Calls
      • macwac, on 02/21/2008, -0/+4I guess the good side is that you will have to lift the 23kg every 4 hours.. so no excuse to not exercise :)
    • j1a1g1, on 02/21/2008, -14/+2823 kg x 9.81 m/s² = 255.63 N
      255.63 N = 57.46 lbs!
      • MindStalker, on 02/21/2008, -15/+8do what?
        Yes 23kb is about 50 lbs..
        Do you mean 57.46 foot pounds?
        Otherwise WTF are you talking about?
        • pixeldust, on 02/21/2008, -0/+25The fact that most people don't want to lift freaking 50 pounds to turn on their light?
        • arcooke, on 02/21/2008, -2/+40According to you, my hard drive should weigh 1,092,266,665 lbs @ 2.17 lbs / KB.
          • dunk71, on 02/21/2008, -2/+1and my arms... they're so very very heavy... can't type... must lie down....
        • pyro789x, on 02/21/2008, -2/+23@pixeldust

          I would gladly lift various weights to power my home if it means I won't have to pay a dime for the energy I use. Hell, that would just help to keep me in shape. I need the exercise anyway.
          • FatLoser, on 02/21/2008, -20/+4"I need the exercise anyway."

            I bet you do, chubby fatterson.
          • Treshnell, on 02/21/2008, -6/+5Hello, irony.
          • FatLoser, on 02/21/2008, -10/+5Hello, whooosh.
          • TheOther1, on 02/21/2008, -3/+6Right, because food is free.
          • phronko, on 02/21/2008, -0/+1If someone's fat, they're eating too much food anyway. Might as well convert the extra into light.
        • Murdats, on 02/21/2008, -0/+26maybe we could create some sort of mechanism to lift the stuff for us, maybe power it off electricity.
          • theymos, on 02/21/2008, -0/+20Good idea! But to save money, why don't we use something to generate the needed electricity ourselves; perhaps involving gravity?
          • AxeSwinger, on 02/21/2008, -0/+5I'm thinking a metal coil, a gerbil, scissors, fan, tub and a toy sail boat. But for the life of me I can't figure how to get 200 years out of the gerbil. Maybe a male and female rodent but that just seems like the easy way out.
          • JohnFlux, on 02/21/2008, -0/+1Actually that's not such a silly idea.

            if you raised it during the night, when electricity was much cheaper, then used it during the day, you could save some money. Some hydrodams do something similar and pump water back up during the night :)
        • InfiniteNothing, on 02/21/2008, -7/+3N and lbs are both measures of force
      • soccerman90, on 02/21/2008, -18/+2i dont think it is falling at 9.8m/s It is falling slow enough so it takes 4 hours to fall from the top to the bottom
        • hangglide, on 02/21/2008, -1/+7The strength of the gravitational field is numerically equal to the acceleration of objects under its influence, and its value at the Earth's surface, denoted g, is approximately 9.8 m/s².

          *note: this description was taken from wikipedia.
        • NJHiker, on 02/21/2008, -2/+6While it is correct that the acceleration due to gravity is 9.81 m/s², forces resisting gravity such as buoyancy and drag will make the net downward acceleration of this 23 kg mass considerably less.
      • yunus, on 02/21/2008, -1/+201.21 gigawatts!
      • dinostabOMG, on 02/21/2008, -1/+18Was that easier than typing "23kg to lb" in Google? Or indeed multiplying by 2.2?
        • PlancksCnst, on 02/21/2008, -1/+2Maybe not, but it was technically correct since kg and lb measure different things (one is mass, the other a force).
      • unearth, on 02/21/2008, -0/+5You calculated wrong, its 225.63 N
        • InfiniteNothing, on 02/21/2008, -0/+3Indeed: I'm not quite sure how he got 23 * x where x is < 10 to be > 230
      • scoffey, on 02/21/2008, -0/+12kg is mass, N is force
        slugs is mass, lbs are force
        kg and lbs are not equivalent units
        also, lb*ft is a measurement of a torque or a moment

        just to clear up some quick dimensional confusion
        • funktimus, on 02/21/2008, -0/+6ahh yes, the slug.
          I'm not passionate enough to ever get a phD in physics. But if I did, you best believe my goal wouldn't be to discover some brilliant law of the universe. Rather I'd become a professor at some school doing just enough to earn tenure. After securing tenure, you best believe all the introductory physics students would be doing slug-based calculations...
        • goldisalie, on 02/21/2008, -1/+4There are two pounds, the pound-force and the pound -mass... The slug is a measure of mass entirely different to the pound.

          FFS just go metric!
        • brufleth, on 02/21/2008, -0/+1The poster's point was to give US audiences a better idea of what 23kg is. That number might mean more to someone in a metric country but in the US the pound is more familiar. We're also talking about here on earth either way so converting to pounds to give a more visceral idea of what that means seems reasonable.
        • senatorpjt, on 02/21/2008, -1/+2Considering this thing works on gravity, pounds is actually more accurate. This thing wouldn't work in space because the weight would be 0 pounds.
    • Kingster, on 02/21/2008, -21/+28My guess is that you don't understand the design entirely. http://www.core77.com/competitions/greenergadgets/ ...
      • chrispeters, on 02/21/2008, -6/+24This lamp can only start with so much potential energy. You can't create energy out of thin air, so it either needs a massively heavy weight on it, or needs to fall an incredibly high distance. It doesn't matter how good the design is, it's simply not possible.
      • alexidoid, on 02/21/2008, -7/+23My guess is that you don't understand physics entirely.
      • Devrdander, on 02/21/2008, -7/+4Its clear how they expect it to work, problem I see is that there is a limited amount of Potential Energy in the system, and AFAIK from my phsyics courses, and i didn't do a lot of Electro-Magnetism, when you have a Rotor generating electricity, as you draw current form the system it creates a magnetic field which will cause resistance. Its basic conservation of Energy, you cant get more energy out than you put in and Gravity is a VERY weak force... You can make a weight that will spin down a threaded rod (or spin a threaded rod) and it'll be fine and dandy, hook that motion to a Generator and you have to have enough force to turn the generator while an electric current is being drawn.
        • bowe, on 02/21/2008, -0/+1What are you talking about? Gravity is plenty strong enough to overcome the potential across the generator when one of the 2 masses happens to be the ***** EARTH. The energy input is lifting the weight, which stores potential energy. You will have efficiency losses as you convert this potential energy into light.
      • harlowsmonkeys, on 02/21/2008, -5/+22My guess is that you don't understand the law of conservation of energy.

        Start with the light in the run down state. A human lifts the weight. That puts energy into the system. The system then uses that energy to produce light. NO MATTER HOW IT WORKS, it can't produce more light energy than there was energy put in by the human lifting the weight against gravity. That is enough energy to produce 600 lumens of light for around a minute.
        • astraycat, on 02/21/2008, -14/+1I disagree, surely there's energy stored in a magnet, as they don't last forever and they have a force of their own. It doesn't just come out of thin air.

          By using the weight to turn the magnets it converts some of that stored energy into electricity which then is converted into light. Setting the weight is like lighting a match, it just starts a kind of reaction and the magnets will eventually run out of power and just become rare earth metals.

          Since I don't know anything about magnets and how they work, this is just a guess. But surely magnets don't stick to my fridge for free, right?
          • nepawoods, on 02/21/2008, -0/+1In principle, a magnet can stick to your fridge for free. Some magnets become weaker - this is not a loss of energy.
          • Scienceisfun, on 02/21/2008, -0/+0This is not free! If it were free, it would violate the laws of thermodynamics! A magnetized object has more energy than a non-magnetized object. The magnetized object sticking to your fridge has less energy that it did when it was far away from the fridge. This is because the magnetic field of the fridge magnet is reduced when it comes close to the fridge.
          • kh99, on 02/21/2008, -0/+0@scienceisfun - Aha - this is what I was missing above (I should have kept reading comments). A magnetic field is reduced when metal comes near it, so the energy is reduced. Thanks.
        • rompom7, on 02/21/2008, -0/+7I'm gonna make it simple: No magnets do not store energy. A force is not equal to energy.
        • goldisalie, on 02/21/2008, -0/+3sorry astraycat, it just doesn't work like that. as rompom said, a magnet applies a force, like gravity does, but energy is entirely different.

          Think of this, kinetic energy is the energy associated with the falling of the mass. Gravity itself is no different between the two states of the mass, ie at rest and in motion, but when the mass is on the floor how much kinetic energy do you think it can acquire without some sort of input (increasing the potential)... this is assuming a hole doesnt appear in the floor below it, ie we are assuming the rest position on the floor == zero potential e (for arguments sake, an entirely valid assertion given the circumstances).

          Yes, I'm a 3rd year mech engineering major :)
        • Scienceisfun, on 02/21/2008, -2/+3Astraycat is right -- there is energy in a magnet. If you use a magnet to lift a piece of metal off the ground you impart potential energy to the piece of metal -- that energy comes from the magnetic field. It has to come from somewhere, after all. Force and energy are inextricably linked: work = force x distance. However, that is largely irrelevant to this case. The magnets are just part of a generator. By moving a conductor through a magnetic field you generate current -- this doesn't actually steal energy from the magnets. It steals it from the kinetic energy (translational or rotational) of the conductor. That's how pretty much all AC electricity is generated. In any case, there just isn't enough stored magnetic energy (even if you could harness it) to make this explanation possible. Magnetic energy density = (magnetic field strength)^2/(2 x permeability of free space). For a big (big!) 1T, 1m^3 magnet, you get 400kJ of magnetic energy. Do the math and you'll find that gives you about 111 hours of light, given a 1W light source. But then you need a new magnet -- not quite a 200 year lifetime.
          • nepawoods, on 02/21/2008, -0/+1"If you use a magnet to lift a piece of metal off the ground you impart potential energy to the piece of metal -- that energy comes from the magnetic field."

            It depends. If you are lifting the magnet, you impart potential energy to the attached metal object through your own lifting. On the other hand, if the magnet were somehow fixed above the metal object, and the metal object jumped up to stick to the magnet, no potential energy is imparted, and more than potential energy is imparted by the object falling (being attracted through gravitation) to the ground. Not, if you use some muscle again and separate the metal object from the magnet, so that it may fall, you have now imparted potential energy to it, but again, through the application of muscle.
          • Scienceisfun, on 02/21/2008, -0/+1Sorry, I was ambiguous. I'm talking a suspended magnet causing a piece of iron to jump off the table and come into contact with the magnet. In this situation you absolutely do change the gravitational potential energy of the piece of metal -- how can this not be true? You've moved a mass against a gravitational field -- that implies that work has been done. This energy comes from the magnetic field! Where else could it possibly come from? The magnet hasn't changed it's gravitational potential energy, but the piece of metal has! Bringing the metal close to the magnet reduces the magnet's magnetic field, and reduces the stored energy in accordance with the conservation of energy. Pulling the piece of metal back to the table's surface takes the gravitational potential energy of the metal plus the work you do against the magnetic field and puts that energy back into the magnetic field (ignoring things like hysteresis).

            Instead of magnets, consider electric fields. Let's say I have a negatively charged mass sitting at zero volts and zero height. Let's say I turn on a -10 volt capacitor plate 1 meter above the mass, but keep the mass fixed in place. The mass now has a heck of a lot of electrical potential energy. If I let the mass go, it will accelerate into the top plate, exchanging some of it's electrical potential energy for gravitational potential energy and some kinetic energy. In terms of fields, the object takes energy from the electric field and puts it into the gravitational field. Both gravitational and electromagnetic fields store energy. A permanent magnet does store energy, just like a capacitor or an inductor stores energy. If you believe that a magnetic field can cause an object to accelerate, you have to accept that the magnetic field stores energy -- to wit, a piece of iron attached to a magnet has less potential energy than a piece of iron far away from that magnet.
          • kh99, on 02/21/2008, -0/+0@Scienceisfun - so if what you're saying is true, if I let a paper clip jump up to a magnet, I've used up some of the energy from that magnet to create the new potential energy of the paper clip. But if I drop a paper clip on to a magnet from above, I must have used up less of the magnet's enegy because I didn't add any potential energy to the paper clip? Hmm...I'm not sure I buy that - but I suppose it's possible.
          • Scienceisfun, on 02/21/2008, -0/+0And crap to my mistake, I meant a positively charged mass at zero volts, not a negatively charged one.
          • Scienceisfun, on 02/21/2008, -0/+1@kh99
            The missing piece is kinetic energy. If you use a magnet to pull something up off the ground you have the magnet pulling up working against gravity pulling down. The difference in forces leads to an upward acceleration and some final kinetic energy right before the object hits the magnet. You will find that the energy at the beginning (zero gravitational energy, zero kinetic energy, non-zero "magnetic potential energy") is equal to the energy at the end (zero magnetic energy, some gravitational energy, some kinetic energy). In the other case, where the magnet is at the Earth's surface and you drop the paperclip from above, you'll find two downward forces causing acceleration and that the object's final velocity is greater than what you'd predict due to gravity alone. In this case, the energy at the beginning (zero kinetic energy, some gravitational energy, some magnetic energy) is converted entirely to kinetic energy, but the exact same of magnetic energy is used up. By the way, magnetic energy is a horrible term, since magnets themselves do no work by virtue of the absence of magnetic monopoles. Magnetic fields only exist when there are moving charges about, and it is actually more subtle electric fields that do the work that I am attributing to magnetic fields. Magnetic energy is actually better termed electrodynamic energy to indicate the presence of charges in motion.
          • kh99, on 02/21/2008, -0/+0@@Scienceisfun - but according to your description the total energy is the same before and after, so you have not "used up" the energy that was stored in the magnetic field. I'm not a physics expert so I could be wrong, but even though a magnetic field itself can store energy, I don't think this is the same energy being "used up" when you accelerate something with a magnet, in the same way that the gravitational field of an object is not "used up" when another object gets closer to it.

            Or I guess another way to say this is, you ask "where does the energy to accelerate come from?". Well, gravity can accelerate things, where does that energy come from?
          • kh99, on 02/21/2008, -0/+1@@scienceisfun - if you come back, don't bother using time to respond to my previous comment - I didn't express myself clearly, and now that I've thought about it (and specifically what you could do by turning on and off an electromagnet), it's obvious that I'm wrong somewhere. Thanks for your previous comments - it's rare on digg to actually have a good discussion about something.
          • bowe, on 02/21/2008, -0/+1It's really simple, an object existing in any sort of force field has potential energy unless it's at the point of lowest energy. This applies to both gravitation and electromagnetic fields. Objects always seek the lowest point of stored energy. An object jumping from the ground to the magnet is seeking it's lowest potential energy state.(moving with the gradient) It has a lower potential moving to the magnet than it does staying on the ground.
      • Brian48216, on 02/21/2008, -27/+4Every single one of you fail.

        The design states that it emits light for FOUR HOURS.

        The fact it uses LED means it would not break in 200 years.
        READ GOD DAMMIT!!!
        PULL YOUR HEAD OUT YOUR ASSES.
        • kh99, on 02/21/2008, -4/+21We get that. The point is that it can't possibly emit light for even 4 hours. You're telling people to read when you apparently haven't even read the comments you're replying to? Idiot.
      • xptoast, on 02/21/2008, -9/+2Why is it so hard to believe something that already currently exists in a physical form and has been used? That is like saying my icecream here doesn't exist or cant work because you cant see it or don't think I am a person that would eat icecream. It exists so shut your faces.
        • Tossrock, on 02/21/2008, -1/+0Wrong!
        • xptoast, on 02/21/2008, -1/+1Toss...Do you actually have a reason you said wrong or did you just want to see your own text?
      • Theycallmetak, on 02/21/2008, -1/+2My guess is nobody noticed yet that acrylic is misspelled in the pic you linked.
      • sportbikepilot, on 02/21/2008, -0/+1why the hell are the LEDs on the floor?
    • zKman, on 02/21/2008, -5/+138Let's look at the claims of light output. It says for 4 hours, this thing will output 600-800 lumens. White LEDs have a luminous efficacy of 10-90 lum/W. Let's assume 600 lumen output at 70 lum/W efficacy. So, the power required for this stated output is:

      600 lum/(70 lum/W)=8.5 Watts

      This seems to correspond to LED bulbs with similar light output. http://www.treehugger.com/files/2007/02/led_bulb_r ...

      8.5 watts over 4 hours is 120000 joules of energy.

      ---

      Now, let's look at the energy that this can produce. Considering the 50lb brass weight inside (23kg) and the 48in it will fall (1.2m), we have:

      U=23kg*1.2m*9.8m/s^2=270 joules

      This thing has a potential of producing 270 Joules of energy if 100% efficent.

      ---

      270 J is three orders of magnitude off of 120 kJ. I hate to poo-poo on a fellow hokie, but I think this guy's being a bit liberal with the numbers.
      • Lutomes, on 02/21/2008, -25/+7I don't know if I should digg you up or down.

        On one hand you present an excellent calculation of the energy from the weight drop, compared to the energy from the bulbs.

        On the other hand you have completely ignored the design of the lamp and how it operates. I recommend you actually read the competition page http://www.core77.com/competitions/greenergadgets/ ...

        Overall I'm impressed with the device. I'm not sure how innovative it really is, but it looks nice to me. Wonder how much it costs though.
        • zKman, on 02/21/2008, -0/+7Sure, the drawings look neat, however, no designs are provided of the ball-screw, harmonic drive gear head, or rotor/stator. This thing should be taken as is: a CAD drawing, not some sort of engineering feat.
        • countingthedays, on 02/21/2008, -1/+25Regardless of how the device is constructed, there is a limited amount of energy at hand here. If you put 270J in, thats all you can get back in light. The original poster was spot on.
        • ptron, on 02/21/2008, -1/+7Total aside, but there's only one company that make harmonic drives, HDT and they are not cheap, they are also at best 80% efficient. The only reason to use a harmonic is to save weight since they have the highest gear ratios per unit mass of any gear train, hence why they were used on the lunar rover for Apollo. This design is *****, that's why it only exists in CAD.
        • roodammy44, on 02/21/2008, -0/+6Yes, lets ignore physics and take the pretty picture as the answer
          *claps retardedly*
        • IanCal, on 02/22/2008, -0/+0> On the other hand you have completely ignored the design of the lamp and how it operates. I recommend you actually read the competition page
          Actually, I have read it. It would still violate the basic laws of physics.
          > Overall I'm impressed with the device.
          Why? It's highly impractical, and not even particularly innovative. The design is nice, but it won't work.
      • Devrdander, on 02/21/2008, -2/+8Even if you take into consideration the new 300lm/w LED's that they just demonstrated (in lab only not mass production), it still would only last a few minutes... http://technology.newscientist.com/channel/tech/dn ...
      • caltrop, on 02/21/2008, -2/+13Physics be damned! Simply replace the generator section with an orbo free energy device and all these silly energy conservation problems disappear.
      • Aadain, on 02/21/2008, -16/+14The "secrete" to the system is the neodymium magnets in the base, which the weight is causing to rotate. So all the nice physics calculations are completely missing the true source of power in the system. The weight moving down is only used to produce torque to spin the magnets, releasing their energy through electro-magnetic conversion. The system won't last forever, but I would believe it would last 200 years since neodymium magnets are strong suckers and it would take a while to drain their magnetism with simple LEDs.
        • rfordh, on 02/21/2008, -1/+7Are you joking?
        • zKman, on 02/21/2008, -3/+12No. If you put 270J in, you will only get 270J out. Spinning magnets made of whatever material won't change that. Also, there is no such thing as "draining magnetism" for energy. The magnetic field of magnets remain constant over time.
        • d03boy, on 02/21/2008, -4/+3Pretty sure magnetic field can be reduced if electrons are lost
          • rompom7, on 02/21/2008, -0/+4Yeah, it can. But you can't access that energy that has been lost.
          • rootneg2, on 02/21/2008, -0/+1and what, you end up with a bunch of positively charged magnets?

            what do you do about the static buildup? you can only lose so many electrons before they arc and redistribute the charge, and it won't be all then many compared to how many you would need to demagnetize neodymiums.
        • karmabandit, on 02/21/2008, -2/+13This is not a difficult concept, people. Would this lamp make light without the mass falling down? No! Therefore it's getting the energy from the mass. I don't care what kind of ridiculous crap you use to turn that energy from gravitational potential energy to electrical energy, like magnets, you are getting the energy from one place (gravity) and it's ending up in one place (electricity)... or lost to friction, I suppose. The end. Why is this so hard to understand?
          • Koookie, on 02/21/2008, -5/+3That is like saying the following:
            Your car won't work without electricity (because of spark plugs), therefore it's powered by nothing but electricity.
          • troon, on 02/21/2008, -1/+3@kookie - only if you're an idiot. The only energy source added to a car is the petrol (gas, diesel, whatever) - so that's what the car runs on. The only energy source in this lamp is the conversion of gravitational potential energy to kinetic energy. Taking the above posters' calculations as read, that's 270J.
          • kh99, on 02/21/2008, -1/+2@Koookie - no, because a car has gasoline as an energy source. If you can point to another source of energy for this lamp, please do. (BTW, magnets are not an energy source).
          • Koookie, on 02/21/2008, -3/+3@troon
            P => Q, where:
            P = Would this lamp make light without the mass falling down? No!
            Q = it's getting the energy from the mass.

            Can't you see a flaw in this reasoning? Note that I don't say Q or !Q.
          • Koookie, on 02/21/2008, -2/+2@kh99:
            Okeys. I don't know enough about this, but basically permanent magnets do store energy -- just not enough to work as claimed here. I'm not sure if the energy can be released of tapped in to. You're probably thinking that I'm on "their side" -- but I was only pointing out the false argument.

            Vicky P. says: (some parts cut)
            ---
            Neodymium magnets are graded in strength from N24 to the strongest, N54. The number after the N represents the magnetic energy product, in megagauss-oersteds (MGOe) (1 MG·Oe = 7,958 T·A/m ≈ 7,958 J/m³)
            ---
            1 liter of the weakest N24 magnets would hold: 24 · 7,958 J/m³ · 0.001 m³ ≈ 191 J of energy.

            The energy is stored when the magnet is manufactured.
          • kh99, on 02/21/2008, -0/+1@@Koookie - OK, magnets have energy, not enough energy to run the light as claimed plus no way to extract it, so they are not a source. But I see, you have no real point, you're just nit-picking. Fair enough.
        • mre5765, on 02/21/2008, -4/+1"it would take a while to drain their magnetism with simple LEDs."

          OMFG. You're an American aren't you?
        • Tossrock, on 02/21/2008, -1/+3Who the ***** is digging this guy up? This is a ***** FARCE, I learned how to calculate potential energy in like 7th grade
          Christ.
          This is what happens when you marry your cousins and let your kids drop out of school.

          Of course, if he's actually joking, I'll feel a tiny bit bad, but really.
          Kaufmanesque humor is about 3 orders of magnitude over this guys head.
      • whodathunk, on 02/21/2008, -1/+7But he didn't have to obey the laws of thermodynamics. He doesn't believe in them, he used intelligent design instead. ;-)

      • unpolloloco, on 02/21/2008, -0/+3well, we all know that thermodynamics is a big government conspiracy propagated by the oil companies...........yeah thats it.......sure.......
      • rootneg2, on 02/21/2008, -0/+6for the curious (and assuming ~300 lumen/watt LEDs which are super-duper bleeding edge still in research phases efficient)

        discounting the quoted duration, and obtain the 600 lumen output with the same duration, but the light would only stay on for 2.4 minutes
        discounting the quoted height, and it would have to be 400 ft tall
        discounting the quoted weight, it would be about 5 tons

        interestingly enough, working through the calculations it seems like everything is off by *precisely* a factor of 100. I'm thinking somebody "misplaced" a decimal....
        • rootneg2, on 02/21/2008, -0/+5gah, sorry, i converted wrong: it would be about 2.3 tons
        • Animal, on 02/21/2008, -0/+4At least YOU corrected your mistake.
        • NickSentowski, on 02/21/2008, -2/+1100 to 1 gear ratio?
      • Fifthrayne, on 02/21/2008, -1/+1I think you are being liberal with the definition of "orders of magnitude." But other than that, you're spot on.
    • kronso23, on 02/21/2008, -14/+113I don't see YOU inventing a gravity lamp.
      • Animik, on 02/21/2008, -2/+15That's because it's already been done...
      • blazes816, on 02/21/2008, -1/+29Plus, anti gravity lamps are way cooler.
      • rompom7, on 02/21/2008, -1/+2Plus, I had this idea as a kid, except even I knew then that I'd need more than 23kg to run it for a few hours.
      • brufleth, on 02/21/2008, -0/+2Know those flashlights that have a weight inside that you shake to charge a battery to light an LED? Yeah, that's all this thing is but with some hand waving and incorrect calculations to make it seem more amazing. There's a different kinetic energy to electrical energy conversion process but it is still doing the same thing and it still wouldn't work as stated.
    • crash331, on 02/21/2008, -12/+20Yeah, this is pretty lame and a bogus title. Buried for inaccuracy.
    • morcheeba, on 02/21/2008, -1/+76Maybe it's only for use on planets with a gravity of 3800 m/s^2
      • elnerdo, on 02/21/2008, -3/+49Like the sun.
        Interestingly, the sun IS a gravity lamp, Gravity crushes atoms, atoms emit light.
        • Synova, on 02/21/2008, -0/+24Like putting too much air in a balloon!
        • FoolsRun, on 02/21/2008, -0/+24It's so simple!
        • InfiniteNothing, on 02/21/2008, -0/+8I think you just figured out how the lamp could generate more energy than it's gravitational potential
    • blitzer, on 02/21/2008, -43/+18What is this.. the ***** nerd olympics? Put your calculators away.
      • Devrdander, on 02/21/2008, -4/+38the jerk store called, they're running out of you!
        • innocentsinner, on 02/21/2008, -4/+15I slept with your wife
        • keidjxz, on 02/21/2008, -0/+9His wife is in a coma
        • Ph34rb0t, on 02/21/2008, -1/+1Which made it that much easier. Not all of us have the benefit of living/conscious girlfriends.
      • SeventhSon, on 02/21/2008, -6/+7Nope. The Nerd Olympics was last month. I owned.
      • Tossrock, on 02/21/2008, -2/+2Shut the ***** up, dumbass!
      • sportbikepilot, on 02/21/2008, -2/+1what are you doing on the computer? shouldn't you be out playing grab ass football with the boys in the frat?
      • arcangelgabriel, on 02/21/2008, -0/+2My friends, here's the future of America.
    • Rocketman1882, on 02/21/2008, -23/+11I stopped reading as soon as you said "23kg weight." *bzzt*
      • bromac, on 02/21/2008, -0/+24The object is called a weight. It has a mass of 23kg. For example, you lift weights, not masses.

        Smart ass. But don't worry, this thread's full of them.
      • thebellmaster1x, on 02/21/2008, -0/+123 kgf. Happy?
      • brufleth, on 02/21/2008, -0/+1And the fact that you couldn't see passed that makes you the idiot.
    • hoisen, on 02/21/2008, -9/+67I like cats
      • badjoke, on 02/21/2008, -1/+20I prefer turtles.
        • Fartag, on 02/21/2008, -0/+12Unfortunately, from zKman's derivation, you'd need to replace the 23 kg weight with over 11,300 box turtles to power this lamp for 4 hours. :(

          (120kJ / 270 J) * 23 kg * (1 box turtle / .9 kg)
      • ZMerlin, on 02/21/2008, -0/+3Dogs are good too though.
      • btnheazy03, on 02/21/2008, -0/+3I like cats too, although I refer to them as kitties.
    • npg6913, on 02/21/2008, -12/+10yeah, shame that the light bulb people use now is the same light bulb we've been using since it was invented, at least the kid is striving for something new, no one is asking your ungrateful self to buy it
      • InferiorWang, on 02/21/2008, -1/+8Yeah, the same light bulb except for the filaments and gases and all that.
      • Phatt138, on 02/21/2008, -0/+8Seriously. You know that light bulbs have changed pretty greatly and at a consistent pace for as long as they've been in production, right? And that's just incandescents. The past 40 years have seen even bigger changes.

        At any rate, either way the kid hasn't made a breakthrough in lightbulb technology, he's proposed a different style of lamp. It's not exactly the first time that people have thought of using gravity as a power source. I'm sure someone's done this in their toolshed and not even thought the results important enough to share. He just did some concept art of a pretty face for an ancient idea. No one's labeling this 'inaccurate" because they don't welcome change (or even cool lamps), but because his claims are physically impossible, even given impossibly flawless engineering.
      • IanCal, on 02/21/2008, -0/+3Even if that were so, IT DOESN'T WORK AS CLAIMED. It's not going to light up for 4 hours, it's going to be a couple of minutes, max.
        He also hasn't invented a new way of generating electricity, or a new type of light. All he's done is put two things together into a form that will be virtually useless.
        So, what I'm really calling him up for is lying, plain and simple.
      • pfromg, on 02/21/2008, -1/+1shame nobody has invented a more efficient light bulb.
        If you consider the manufacturing costs, the life span and the cost of recycling, your modern so called "energy saving lightbulb" is far worse than the traditional lightbulb.
        Just go ahead and try to recycle one of the new lights , they are full of crap thats hard to kill.
        Your traditional light bulb is just glass , cheep metals , and a bit of plastic or ceramic.All of which is not only available in quantity, but cheep to produce , cheep to dispose of , and most of all , effective to recycle.

        Energy saving lights are a scam, they cant ever save as much energy as they cost.

      • rspeed, on 02/21/2008, -0/+2This light uses LEDs, which are a completely different way of creating light than an incandescent or fluorescent light bulb. They're far more efficient and never burn out. The only downside is that they're larger and have a higher initial cost.
    • chingy1788, on 02/21/2008, -1/+7Is this a concept or did they actually make one that works as claimed?
      if they did and it runs as claimed then theres something wrong with your physics...
      If they didn't make one, and the digg user calculations are correct I wonder how this got into 2nd place...
      • charlietuna, on 02/21/2008, -0/+7''Concept illustrations of Gravia depict an acrylic column a little over four feet high...''
        Not even a real device. Clever, but more hype than anything else.
      • DokGonzo, on 02/21/2008, -0/+11Well, if my calculations are correct, when this baby hits 88 miles per hour, you're gonna see some serious *****.
    • ShnowDoggie, on 02/21/2008, -7/+2He is a Genuis (like a fox). Did you see the part about patent pending? If he get the patent, then will he be able to ague that all gravity feed LEDs devices that are sold will have to pay him a royalty? I hope not. But the answer may be yes, even if clocks and other devices have been doing this for a long, long time.
    • jgzman, on 02/21/2008, -7/+4I should point out that
      A) you don't need to lift it every four hours, unless you need light constantly. Minor point, I know.
      B) if I'm reading TFA correctly, it is rigged like an hourglass, so you just have to flip the entire construction. A fifty pound hourglass isn't too bad for four hours of light.
      sub-B) OK, read another FA. Ignore B. However, I still like the idea.
      • IanCal, on 02/21/2008, -1/+1C) It will give light for at most a few minutes, given perfect engineering, no loss of energy anywhere and more efficient leds than currently exist.
    • ccoch, on 02/21/2008, -8/+1Did you read the whole article or immediately start critique it? Your equations are wrong because they don't account for the spinning. So I guess you're the genius.
      • SynchCounter, on 02/21/2008, -1/+8Nope, spinning doesn't matter. You don't have a fundamental grasp of mechanics, and you know that. Why are you arguing the point here?

        There are some very simple rules in physics, and conservation of energy is one of them.

        If you put X amount of energy into a system, and no other energy comes in, and no other energy can be generated within the system (we often don't include sources of energy within a system that we assume will not be tapped when dealing with a particular problem), then you only have X energy to convert to another form. Period.

        You can spin it, you can flip it, you can convert it to 70 different interim forms, the bottom line is, you have X energy to use. Period. All that other crap is probably only making it worse! A perfectly reversible process would let you convert that X energy back and forth between two forms indefinitely, but we don't have truly reversible processes in real life, and even if we did you STILL only have X energy to deal with!

        There are good reasons to do all sorts of things in physical devices, but nothing that you do will make energy out of nothing. There's something else other than gravity that's making the light, if it does what it says it does.


        • SolitarySoviet, on 02/21/2008, -5/+1so with what your saying if I put x amount of force into a snowball with my pinky finger and it rolled down a hill it could never pick up speed or more snow (spending energy by picking it up more snow and moving its mass from a resting state to moving state) and eventually hit at the bottom of the hill having enough energy to smash a car? I think that is a prime example of gravity adding energy to the equation as is something falling until it reaches terminal velocity... so I dont see why gravity couldn't keep pulling on the weight adding speed to its spin and making more energy than the initial spin... that wouldn't violate any law would it? the energy isnt comming from nowhere its gravity.... any given spot on earth is not exactly a closed system by any means... and obviously the damn thing does SOMETHING or it wouldn't have gotten an award... im sure as ***** that they had the guy demonstrate it at least once wouldn't you agree?
        • usaar33, on 02/21/2008, -1/+4Wow, did half of digg fail high school physics?

          The potential energy of the snowball is relative. In your example, its potential energy is based on the height difference between the car (base of hill) and the top. Gravity is only converting that potential energy into kinetic (the speed).

          The actual source for the energy is not your picking up the ball (1 meter), but the sun which took the water off of the ground (transferring radiation energy into an object's potential energy) and put it high into the sky. A lot of that potential energy is lost as heat when it snowed, but there is still enough to "smash" cars.

          On a side note, why are digg captcha's not even human readable? I have to try 5 times until I even get them right.
          • SolitarySoviet, on 02/21/2008, -1/+1I think you missed my point and are now splitting hairs... in my example I used snow and you focused on the energy it has from being snow which even after you went on a tangent and talked about the sun putting energy into it. doesnt change the fact that none of that snow released its energy as heat or was spent as fuel and all of its energy is still there sure its smaller balls of snow but no mass was taken away and converted to energy...(friction yes but that would be more splitting of hairs) so substitute it with mud or really anything thats mass isnt being destroyed evaporated etc.. hell you could say a cannon ball set on top... what I meant was that an object with any mass when resting if pushed would accelerate because of gravity while rolling down the hill (cant freefall due to the ground and gravity causes it to spin forward seeking the lowest point), so its gaining kinetic energy gained by nothing more than gravity and that energy is far greater then the small push my little finger had to start it.... due to outside forces acting on it joules put in < joules taken out... that doesn't violate any laws and no energy is coming from nowhere. its like swimming with the current or against it. one direction your going to have to spend alot more energy just to move and the other direction you will accelerate faster and faster with the same amount of work, the device in question is just using the natural pull of gravity to help him do more work than he put into it, which isnt creating energy out of nowhere so its not a problem... in zero g with no other outside forces you couldnt have such a machine. the whole machine is acting like a capacitor charged up by him moving the weight, gravity pulling down. spinning a small set of magnets generating electricity (very slowly demagnetizing them and using them as fuel) and eventually stopping completely once its reached the end of its track. so before you go off on how half of digg failed high school physics, (which Im sure your one of given the USA in your name) pull out your reading comprehension skills and spare me the details of how stars obviously put energy into things...
          • IanCal, on 02/22/2008, -0/+0SolitarySoviet (sorry, can't reply to yours for some reason)
            You expend energy in lifting something up, and can get energy from dropping it down. If you can get more from the latter than was put in, you have created a perpetual motion machine. Feel free to go and collect your nobel prize.
            > (very slowly demagnetizing them and using them as fuel)
            Woah, no. Turn a generator by hand, the energy comes from you, not the magnets. Look up the basic workings of generators.
      • IanCal, on 02/21/2008, -0/+1As already said, the spinning doesn't matter.
        It takes 270J to lift the weight up, if you can get more than that coming down, pretty much all of physics is wrong and this guy as invented a perpetual motion machine.
        Or, he's wrong and basic physics still works.
        There is 270J of GPE, and the spinning will come from that, so you cannot get more than 270J out.
    • Archer007, on 02/21/2008, -0/+6Yay! Free Energy! Wait a sec...
    • BlueTunicLink, on 02/21/2008, -0/+11You could just use portals to create infinite potential energy.
      Problem solved
      • crazyc, on 02/21/2008, -0/+5That would be a triumph...
      • ColonalSanders, on 02/21/2008, -0/+0wouldn't that be infinite kinetic energy, since its energy from motion?
    • bigphildogg86, on 02/21/2008, -8/+0http://www.core77.com/competitions/greenergadgets/ ...

      If you follow that it has more explanations. Yes, I am not an expert, however it appears like a gear type system except using a ball-screw and something other that's "overdrives" at 1:160. I'm just saying it's plausible. Is it not a good mechanical system that runs a car where you just push your foot down and a several ton vehicles moves? I know. Bad analogy what with it all using gases. But still, upconverting the amount of energy I would think is plausible.
      • IanCal, on 02/21/2008, -0/+3It's not. The car gets energy from the stored energy in the petrol (gas).
        It doesn't matter what you use, what gears, what generator, you cannot get more out than you put in. You cannot get more than 270J out of this.
        • bigphildogg86, on 02/21/2008, -0/+0Yeah after I worked on some of the math myself I came to the same answer. Well myself...and a nice online calculator. LoL.
          First this post was good.
          http://askville.amazon.com/yo-measure-electricity- ...
          Then from that post it talks about Work = force * distance
          So 50 pounds over 4 feet = 200
          Then mulitply by 1.36 to find watt-seconds. 200 * 1.36 = 272
          This is actually the same as the joules at this point.
          Now from google.
          272 (watt seconds) = 0.0755555556 watt hours
          Pop that into this handy calculator.
          http://www.mhi-inc.com/Converter/watt_calculator.h ...
          Make sure it's over 4 hours and you see you can get....
          0.01889 Watts.
          So yeah I was disappointed that it wasn't so, but that's okay. I got a little more edumacated today.
    • egonSchiele, on 02/21/2008, -0/+13IanCal, you clearly don't understand the gravity of the situation. So stop throwing your weight around. Let me shed some light on this.
    • ninjan, on 02/21/2008, -0/+4Lifting a 23kg weight 4 ft every 4 hours gives you muscles!
      • sportbikepilot, on 02/21/2008, -0/+2it's split into five 10lb. weights... no power lifting involved
    • Fordi, on 02/21/2008, -0/+3Here's the base math, for those who care for it. You can just type the below into Google and have it do the conversions:
      (((23 kg) * (4 ft) * (9.8 (N / kg))) / (4 hours)) * (150 (lumens / watt)) = 2.86258 lumens

      23kg is the mass of the weight, 4 ft is how far it will fall, 9.8 N/kg is earth's gravity, 4 hours is the proposed falling time, 150 lumens/watt is the efficiency of the new high-efficiency white LEDs, 2.86258 lumens is the total luminous output of the system, regardless of the number of LEDs you use, given 100% efficiency.

      By the way. I love using Google for calculation drafting like that.
      • rootneg2, on 02/21/2008, -0/+1for comparison, a standard 60w incandescent is around 800 lumens.

        no decimals were misplaced.
      • SomeHobo, on 02/21/2008, -0/+1I tried it and Google gives me an answer in "candelas"? am i doing something wrong or is candelas and lumens the same thing?
      • samby, on 02/21/2008, -0/+0Actually, when you cut and paste it, google gives 2.86258 *candelas*, which would be multiplied by 4 pi to get lumens.

        However the right answer is 2.86258 lumens, like you said, which you can see by googling:
        23 kg * 4 ft * 9.8 N / kg / 4 hours *and then* typing in 150 without putting in the lumens / watt factor.

        Seems to be a bug in google. It thinks that candelas and lumens are the same. I'll try to report it.
    • punwin, on 02/21/2008, -0/+123kg is absolutely nothing.
    • k4rb0n8, on 02/21/2008, -1/+1Seeing as it is just a concept right now and with LED technology developing quite rapidly (i.e. expect well over 200 lumens/watt LEDs fairly soon), making the output as high as what he stated will happen and surpassing it is very probable.
      • IanCal, on 02/22/2008, -0/+0You'd need LEDs to hit 600 lumens/watt to have the light go for 4 minutes (assuming no other losses at all). For his claimed figures, you'd need 36,000 lumens / watt, again, if the machine were able to convert GPE to electricity with 0 losses.
    • IglooBurner, on 02/21/2008, -2/+0Its really not that heavy lifting it 4 feet off the ground, most of u guys are just not fit. and for the women and older people out there, I'm sure a mechanism composed of pulleys and levers can be build to help with the lifting process.
      This lamp is still in its early stage, so its really not about what it currently is, its about the potential the idea behind this invention holds.
      • IanCal, on 02/22/2008, -0/+023kg is fine, just not every few minutes. That's the point, it's not every 4 hours, it's 4 minutes given immensely generous figures. More realistically, you'd be looking at well under a minute.
    • susotchka, on 02/21/2008, -2/+0So? ENIAC weighed 27 tons. How much does your computer weigh now?

      http://en.wikipedia.org/wiki/ENIAC
      • stargatesteve, on 02/21/2008, -0/+1woosh.
      • IanCal, on 02/22/2008, -0/+0Wow, you're missing the point so much it's actually painful to read.
        Making it lighter will *make it worse*. Less mass = less GPE = less energy to power lights.
        When LEDs are a thousand times more efficient, then this would work as claimed. I haven't worked it out but wouldn't be surprised if it was impossible to make lights that efficient.
  • dupswapdrop, on 02/21/2008, -7/+28Nice idea kind like a grandfather clock.
    • Mootabolife, on 02/21/2008, -0/+4He should make it even better. Instead of adjusting it, just flip it over. Can you do that to a grandfather clock?
      • redcodenl, on 02/21/2008, -0/+4Even better, attach it to a wall and then flip it, much less physical work!
      • dupswapdrop, on 02/21/2008, -0/+1Yes I have flipped over a grandfather clock, once!
    • MazeKaz, on 02/21/2008, -2/+0That's what she said.
  • tehbeermang, on 02/21/2008, -5/+66Even with it's faults, I'd like to see one in person.
    • Picaroon, on 02/21/2008, -1/+24I wouldn't. After a few years it apparently gets crazed, and then god knows what will happen.
    • H0tKarl, on 02/21/2008, -1/+10You might want to bring a flashlight, just to be safe.
    • joegibes, on 02/21/2008, -1/+12Even without its faults, I don't like to see an unnecessary apostrophe.
  • Falldog, on 02/21/2008, -5/+12I have one of those stupid goop filled (hour glass like) things that I turn over several times throughout the day. If I had something like that which made light? Awesome.
    • morpheus69, on 02/21/2008, -3/+8You smoke a lot of pot, don't you...
      • jb0nd38372, on 02/21/2008, -1/+0Raises hand, while looking at a Hershey's candy bar.
    • rentmitchum, on 02/21/2008, -0/+5That's what she said?
  • jmpeagle, on 02/21/2008, -3/+79so what won first prize if this won second?
    • turpenine, on 02/21/2008, -15/+48your mom
      • badjoke, on 02/21/2008, -1/+18I guess we know who won the creativity award.
        • diskit, on 02/21/2008, -2/+5Yeah, my mind was totally blown at the originality of that comeback.
    • 11familyguy11, on 02/21/2008, -0/+18http://www.core77.com/competitions/greenergadgets/
      • phybere, on 02/21/2008, -2/+10No way that should have won... it's nothing but an amp-meter, which you can buy anywhere. (most of them you can simply hang around a wire and it calculates the load just by the electro-magnetic field)
      • secondplayer, on 02/21/2008, -0/+3I thought that was a joke picture of a bomb at first
        Then I thought I read about it and hoped that God takes pity on those poor judges souls.
    • NotOptium, on 02/21/2008, -2/+52ANTIGRAVITY LIGHTS!!
    • yojiffyskippy, on 02/21/2008, -1/+1The EnerJar took top prize of the design competition.
    • Super6, on 02/21/2008, -3/+1I thought the Enerjar was cool but the point of the competition was not to make a crappy jar that does what a kill-a-watt already does but to make an energy saving device. The gravia pwned it.
      • ricree, on 02/21/2008, -0/+2Read zKman's post up above. The claims that they are making don't seem to be physically possible. I have no problem with a device that works winning over a cool concept that doesn't actually work as promised.
    • chewties, on 02/21/2008, -0/+7I think this should have taken first.
      http://www.core77.com/competitions/GreenerGadgets/ ...
      • warrenterr, on 02/21/2008, -0/+2OMG, that guy is either being sarcastic and funny or an idiot. Lol
    • pradador, on 02/21/2008, -0/+5The guy who reinvented the multimeter.
    • ColonalSanders, on 02/21/2008, -0/+1Some guys at Aperture Science created a particle displacement gun thingy.
  • dsmx, on 02/21/2008, -19/+3This is a totally pointless lighting system.
    • rentmitchum, on 02/21/2008, -0/+5You're a totally pointless lighting system.
  • bombadier337, on 02/21/2008, -53/+11As a Hokie:
    Virginia Tech FTW!!!

    Go ahead, digg me down!
    • rogersj3, on 02/21/2008, -3/+28Sorry - I don't mind your comment, but I have a policy to dig down all who request it.
    • tekmonkey, on 02/21/2008, -2/+5Wahoowa!
    • AvidPreatorian, on 02/21/2008, -3/+2what a distasteful name too..
    • Modizzle, on 02/21/2008, -0/+1Has tuition and housing costs gone down lately?
  • snowskate22, on 02/21/2008, -15/+54Hmm... seems kinda Hokie to me
    • FatLoser, on 02/21/2008, -3/+16If disobeying the laws of thermodynamics is wrong, then I don't want to be right.
    • ccoch, on 02/21/2008, -1/+2puuunnnnyyy
    • Phatt138, on 02/21/2008, -1/+2ISWYDT.
    • varun1s, on 02/21/2008, -0/+1lol....i don't think everyone got the joke though
  • thadiusdean, on 02/21/2008, -14/+5This is amazing. Such a simple concept, and yet it took this long to utilize.
    • krnldmp, on 02/21/2008, -4/+9No its not amazing. Its a piece of art, and practically useless.
    • Phatt138, on 02/21/2008, -0/+3Getting work from gravity is an ancient idea, and is inefficient for the same reason that this is impossible: it's a diminishing return. The best way of using gravity to light a lamp is the waterwheel.
  • Mikhail101, on 02/21/2008, -1/+10Love the design
    • sportbikepilot, on 02/21/2008, -0/+1but why are the LEDs on the floor?
    • Beakerz, on 02/21/2008, -1/+1definitely... it is the sexiest lamp i have ever seen... sexy. sex. sexlamp.
  • Kingster, on 02/21/2008, -6/+39Here's some more info on it... http://www.core77.com/competitions/greenergadgets/ ...
    Looks like the weights, rather than just falling, actually spin an axle hooked to a gear that spins neodymium magnets (acting as a rotor) inside the base (that acts as a stator). Pretty frickin' cool, if ya ask me. I'd buy one.
    • morpheus69, on 02/21/2008, -5/+16No matter what the mechanism, there's only so much potential energy in a fixed mass falling a fixed distance. The mechanism just makes the system more efficient, but can't exceed the gravitational potential energy.
      Cool, though, and really nice looking too...
      • Aadain, on 02/21/2008, -15/+8The power comes from the magnets. Take a college course in EMF and power generation. The weight only spins the magnets. The rotor/stator is where the real power is generated. The potential energy in the magnets is converted to current through the spinning. So the potential energy in the system is the falling weight AND the energy stored in the magnets.
        • fyngyrz, on 02/21/2008, -0/+16Mmmmm.... no. Try to spin a generator under load. You get strong resistance. That's because as power is consumed, an equivalent force (plus inefficiencies) is fed back through the mechanism through opposing magnetic fields that are set up around the coils of wire. This is why it takes a lot of force to turn a generator shaft (car motor, water wheel, steam turbine, wind, etc.) Power doesn't "come from" magnets; power comes from a magnetic field sweeping across a wire and cause the electrons to move. But when electrons move in a wire, you get back-EMF, which opposes the originally applied magnetic field.

          Basically you don't get anything for free. Or, in this house, we obey the laws of thermodynamics.
        • ricree, on 02/21/2008, -0/+9The only energy being put into the system is the potential energy of the weight. The magnets themselves don't actually contribute any energy to the system, they just provide a way to provide useful power from the change in potential energy of the weight.
        • kroenecker, on 02/21/2008, -0/+6Wrong Aadain. It's the potential energy in the weights that provides your maximum amount of energy.
        • Scienceisfun, on 02/21/2008, -1/+1I have taken a college course in EMF and power generation. The energy stored in a magnetic field is VB^2/2u, where V is the volume of the magnet, B is the magnetic field strength and u is the permeability of free space. For a gigantic 1m^3 magnet with a strength of 1T, the stored energy is about 400kJ. Yup, if you could extract all that energy, that's enough to power a 1W LED for about 111 hours. That's about a month at 4 hours a day. But then your gigantic magnet is dead. Certainly doesn't jive with the 200 year lifetime of the lamp.
        • bowe, on 02/21/2008, -0/+2the energy doesn't come from the magnets! Yes there is energy stored in a magnetic field, but it's not the energy "source". You do work to lift the weight -> Potential energy from the weight -> Kinetic energy in the rotor of the generator as the weight falls -> electrical current induced in the generator coil (energy stored is 1/2 LI^2) -> results in a potential energy difference across the LED greater than the break down voltage -> Release of energy across the LED through ions. That's all that happens. The magnets role is just to aid in the conversion of one form of energy into another.
  • Tyrghast, on 02/21/2008, -18/+3Digg is 12 hours behind slashdot it seems.
    And it's human powered, you have to give a jumpstart with your hand.
    • giveer, on 02/21/2008, -2/+7Yeah, sort of like flicking a switch, huh?
    • turpenine, on 02/21/2008, -1/+5just like another pole I know of.
    • darkane, on 02/21/2008, -1/+1Yeah, we kind of knew that. You know, from the article we all just read. Also, this was submitted to Digg not two hours after it was submitted to Slashdot. Go back and learn your 1st grade math again.
  • bossm4n, on 02/21/2008, -2/+109He needs a gravity powered server that lasts for more than 200 diggs.
    • jb0nd38372, on 02/21/2008, -1/+0How much would that weight weigh? What about that Question bothers me?
    • gwydon, on 02/21/2008, -0/+1Brilliant!
  • eysman, on 02/21/2008, -3/+1how very genie of them,,,
  • shiitake, on 02/21/2008, -0/+13So it's like one of those flashlights you shake, but instead of shaking it, you move the weights to the top of the lamp? That's pretty cool.
    • BriscoeJr, on 02/21/2008, -0/+2You just flip it like an hour glass, and it last 4 hours. Thats pretty amazing.
    • caseyh, on 02/21/2008, -4/+7No, those flashlights use induction. Completely different mechanism. They are the same only in that they input energy from a human to generate light energy.
      • xadhominemx, on 02/21/2008, -0/+8Haha how do you think the kinetic energy of the weights is turned into electrical energy. Hmm... how about induction!
    • mGARANDEUR1, on 02/21/2008, -0/+123kg is a lot of weight to expect people to lift up every 4 hours. Yeah, most guys can do it but it would be better if maybe it was 10lbs plates.
      • bowe, on 02/21/2008, -0/+1You don't have to lift it all at once do you? I think that moving 5 10 pound plates would be easier for most people.
  • gracelly, on 02/21/2008, -7/+3Could not connect: Too many connections
  • AsSubtleAsABrik, on 02/21/2008, -1/+11Well I'm glad to see some Hokies are doing more than me.
  • Vaelkar, on 02/21/2008, -6/+1And the digg effect crashes another server.
  • longbow486, on 02/21/2008, -1/+3http://duggmirror.com/environment/Lamp_Lit_by_Grav ...
  • peregrine, on 02/21/2008, -7/+1www.duggmirror.com

    Also I wish this was available now. Right now.
  • yakvomit, on 02/21/2008, -15/+3genius!? woo look at me I put LED's on a grandfather clock!

    • jawnboy, on 02/21/2008, -1/+12No he did something useful, you just whined on like a little bitch.
      • PaulRay, on 02/21/2008, -1/+1yakvomit. You Suck, Get Off The Stage.
  • lemekim, on 02/21/2008, -18/+42Buried for violating the First Law of Thermodynamics
    • Ogedei, on 02/21/2008, -9/+18Cause transferring potential energy to kinetic energy to electrical energy violates the 1st law somehow?
      • nuggetboy, on 02/21/2008, -0/+13Yes, in this case, because the claim of the light energy output exceeds the potential energy. You can't get more energy out than you put in. Read some of the calcs above (IanCal, zKman e.g.)
      • Fordi, on 02/21/2008, -0/+2See above. The proposed system has enough potential energy to pu out 2.8 lumens over four hours, not 600. That's given 100% efficiency.
    • MrStabby, on 02/21/2008, -1/+10One does not talk about Thermodynamics?
  • Rizmaster, on 02/21/2008, -26/+3Ah, but will it protect you from an asian with a handgun?
    • Typhoon2009, on 02/21/2008, -2/+12I cannot berieve you said that!
      • diggB, on 02/21/2008, -8/+1No, no, no. Chinese people have a difficult time pronouncing R-like sounds. (R's end up sounding closer to closer to W's instead.) So, your sentence really should be:

        "I cannot bewieve you said that!"

        How do I know that? I had to take two years of speech therapy so that I could pronounce "R's" since I was taught how to speak from Chinese parents.
        • Fordi, on 02/21/2008, -0/+1A thick chinese accent always sounded like a hyrbid r-l to me. Just saying.
    • Emnsta, on 02/21/2008, -1/+8Korean
    • MasterThief117, on 02/21/2008, -3/+7Too soon.
  • protodon, on 02/21/2008, -0/+12next, a time-powered orange. amazing!
  • Apoy, on 02/21/2008, -2/+4FTA: 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.

    Who won the 1st place?
  • Mikejoneswho5, on 02/21/2008, -14/+9VTECH JUST KICKED IN YO!
  • ChrisfromNL, on 02/21/2008, -6/+2They should power their servers this way, they might stay online then.
  • pstroll, on 02/21/2008, -0/+3Coming to a Spencer's Gifts near you
    • MasterThief117, on 02/21/2008, -0/+8Only if it will be more phallic.
  • Radical5, on 02/21/2008, -0/+55where can I buy this "gravity"???
    • swissjames, on 02/21/2008, -1/+2send me your bank account details and I'll fax some over
  • BriscoeJr, on 02/21/2008, -3/+0http://www.sierrapacific.com/conservation/home/hom ... These light bulbs produce 800 lumens except they're powered by 124volts.
    • chingy1788, on 02/21/2008, -0/+2well i have one that produces 1500lumens
    • Fordi, on 02/21/2008, -0/+1What's their absolute watt rating? CFL's are usually around 14, so that's around 57 lumens/watt. The best consumer grade LEDs get around 90/watt, and the experimental ones get 150.

      You gotta remember: efficiency is the key to conservation.
      • chingy1788, on 02/21/2008, -0/+1mine is 66 lumens/watt

        I've calculated some lights and cost stuff
        100k hours, 125W incandescent equivalent, 12c/KWH, all AUD
        Incandescents ~ $1.5k
        CFL ~ $400
        LED ~ $200

        I reckon CFL is pretty good already, 100k hours is either 10 years constantly on or 30 years if turned on 8 hours a day
  • mikunter, on 02/21/2008, -4/+14It's the mechanism that will last 200 years, light output will be few hours per "charge". Read the article.
    • ricree, on 02/21/2008, -0/+2Who are you responding to?
    • Fordi, on 02/21/2008, -0/+3A few minutes, if they're even trying to produce a quarter of the light they claim.
  • sdellboy, on 02/21/2008, -3/+28Homer: "Lisa, in this house, we obey the laws of thermodynamics!"
  • TheLastFreeMan, on 02/21/2008, -3/+5So.. are we going to go have a War On Gravity now?
  • carpespasm, on 02/21/2008, -1/+3darn, i thought by 200 years it meant stays lit 200 years on a charge. I'd still get one with it pushing that much light though.
  • BoomChKa, on 02/21/2008, -3/+3This sure beats Hannukah.
  • ja4444, on 02/21/2008, -2/+90Silly student, gravity makes heavy, not light.
    • Chordinator, on 02/21/2008, -1/+9There's that word again; "heavy". Why are things so heavy in the future? Is there a problem with earth's gravitational pull?
    • swatward, on 02/21/2008, -0/+2This just made my week.
    • karel747, on 02/21/2008, -0/+3That was pretty clever...
  • MrJeff, on 02/21/2008, -2/+6Wouldn't just making a plug in floor lamp that uses high output LED bulbs be more worthwhile. It would use very little power, be way less bulky, and you wouldn't have to haul up a 50lb weight every 4 hours. Creating LED bulbs to replace Incandescent or CF bulbs would be even less wasteful as new fixtures would not need to be produced. I see this as at best a niche product for somewhere where power is not readily available such as a cabin.
    I'm a little dubious about the whole competition. They give an honorable mention to a hand cranked mp3 player. They claim the act of cranking it is "emotional content".
    • DeadBabyFloat, on 02/21/2008, -0/+3"Cranking it" is a pretty emotional activity.
    • rootneg2, on 02/21/2008, -0/+1soulja boy told them to
  • Accolade1, on 02/21/2008, -7/+2Doesn't this go against a law of thermodynamics?
    • UKsHaDoW, on 02/21/2008, -0/+4why? its getting the energy from gravity. Just means you have to lift the weight every so often.
      • Accolade1, on 02/21/2008, -1/+0How often?
        • badjoke, on 02/21/2008, -0/+3Read the article?
        • Disfnord, on 02/21/2008, -0/+4According to the article, every four hours. According to the laws of physics, about every minute.
    • Flashman, on 02/21/2008, -0/+5Work goes in, work comes out - nope.
    • Destined, on 02/21/2008, -0/+4I take it you're assuming that it will power the light for 200 years on a single fall? Ah, I love people who need to RTFA.
    • Fordi, on 02/21/2008, -0/+1Yes, but not for the reasons you're thinking.

      See, the concept is sound; allow slow potential - kinetic energy conversion, and convert the resulting kinetic energy into electrical, which is then converted into light.

      The problem comes in numbers. A 50 pound weight falling 4 feet over 4 hours using 150 watt per lumen LEDs only produces 2.8 lumens. For all the work, it'd be pretty dim.
  • joe8pack, on 02/21/2008, -10/+8I once invented a light that was powered solely by photons, the only problem was it wouldn't work in the dark. This was quite troubling after the failure of my solar powered flashlight that only worked outside on sunny days. Its harder than it looks folks - Edison was nearly 85 before he invented electricity and became an overnight sensation. More American inventors go broke by not inventing good stuff than don't.
    • RuthlessPirate, on 02/21/2008, -0/+11You invented a mirror?
    • legendxx, on 02/21/2008, -0/+1try a battery
    • spc4, on 02/21/2008, -0/+2Ben Franklin invented electricity.
    • usafdave, on 02/21/2008, -0/+2Al Gore invented electricity... traitor!
    • Wack3d, on 02/21/2008, -0/+1No-one 'invented' electricity.
      The first research on electricity was conducted many years BC.
      It was Nikola Tesla inventor of AC motors, who made large scale generation and distribution of electricity possible.
      • joe8pack, on 02/21/2008, -0/+1Everyone knows Tesla stole the whole thing from Ben Franklin and Tommy Edison both of whom he worked for. A.C. was just a rip off of D.C. all he did was alternate the currents, I know cause I watch Nova and stuff and they talked about it alot and showed a movie of Ben Franklin and Tesla foolin around with a taser on each other. That's why the gravity light will never be a big success despite only requiring a thimbleful of material from the heart of a dwarf star, because of doubting thomases who say stuff like the stuff that is being said by people saying the stuff.
  • rule110, on 02/21/2008, -0/+6So the cute little weight is at least 48,159.1177 kg. Screw the light!! Where can i get some of that *****!
  • chubbybubba, on 02/21/2008, -0/+31What we need is light powered by Diggers lost hopes and dreams. That thing would be brighter than the sun!
    • chingy1788, on 02/21/2008, -0/+5Digger's lack of girlfriends?
      hey that would be brighter all the stars in our galaxy combined
      • daborg, on 02/21/2008, -0/+6Not as bright as one powered by jokes about Diggers' lack of girlfriends.
        • Chordinator, on 02/21/2008, -0/+1A brighter light than all would be one using energy harnessed from clicks which bury the comments about a Digger having no girlfriend.
  • nubnub, on 02/21/2008, -5/+2Damn it, somebody stole my gravity power idea.
  • Flashman, on 02/21/2008, -0/+3If it lasts 200 years, you'll still need 50 of them to read this clock over its lifespan: http://longnow.org/projects/clock/
    • diggimator, on 02/21/2008, -0/+1Unfortunately, it's a human-powered lamp that requires weight lifting every 4 hours. Not powered by gravity, not 200 years. Just a work out every 4 hours.
  • UltraDavid, on 02/21/2008, -6/+2How about putting an electrically operated gear in there that automatically winds the weight back up when you turn it on and whenever the weight reaches the bottom? I wonder if that'd be less energy efficient overall than just having a regular electricity-run led lamp in the firstplace.

    I don't know. The closest I got to science in college was the political kind.
    • Flashman, on 02/21/2008, -0/+5If you have x amount of energy, you're going to get more light if you put it straight into the LEDs than if you use it to lift a falling weight which drives the LEDs. Otherwise you'd have an overunity device - a perpetual motion machine.
    • UltraDavid, on 02/21/2008, -5/+1It wouldn't be a perpetual motion machine. Let the weight do its gravity thing until it hits the bottom, and then use electricity to pick it back up. The question is which is greater, the amount of energy it takes to constantly power a regular led lamp for 4 hours or the amount of energy it takes to lift the 50lb weight up the some-foot-tall screw. Anyone have any guesses?
      • blate, on 02/21/2008, -2/+0How about a really powerful spring that is released when the weight lands on a panel or something, firing it back onto the top? The only problem would then be resetting a spring that is powerful enough to launch a 23 kilo weight...
      • Dunadan, on 02/21/2008, -1/+3The answer seems obvious to me. It's either electricity to light, or electricity to gravitational potential energy to kinetic energy to electricity to light. both have the 'electricity to light' step but one has several more steps, clearly making it less efficient.
      • sportbikepilot, on 02/21/2008, -0/+1and just where do you suggest we get that energy to lift the weight back up? your ass? most was spent on the powering the LEDs...
    • Fordi, on 02/21/2008, -0/+1Well...
      With a 23kg weight, moving over the course of 4 feet, either by gravity or against gravity, you have 274 Joules, either direction.
      Consider that both lifting the weight and converting its movement to electrical energy are less than 100% efficient. So, the product of those efficiencies (assuming no friction, a motor is around 90% efficient, and a generator is around 50% efficient), 45%, is how efficient your proposed system would be in contrast to directly dumping electricity into the LEDs.

      In short, no. Not a good idea. It's generally not a good idea to introduce unnecessary energy conversion steps, as none of them are 100% efficient.
  • DeFex, on 02/21/2008, -0/+15Just when the sharper image declared bankruptcy too.
    • ninepointfive, on 02/21/2008, -0/+1ahh I know, what a bummer for clay moulton!!
  • RickyBarnes1960, on 02/21/2008, -8/+3Let's see, devices that generate their own electricity or dozens of little transformers (per household) sucking the expensive and polluting juice from a power plant scar on the land? Wanna be a slave to the utilities your entire life? Go ahead.
    • SynchCounter, on 02/21/2008, -0/+3Are you referring to grassroots power generation in general, or this little device?

      Cause it doesn't work. Sorry.

      And if it does, it doesn't work the way they say it does.
    • Fordi, on 02/21/2008, -0/+3Grass roots generation is nice and all, and I've even done a lot of thinking and engineering around the idea myself. But small-scale generation just isn't even in the same efficiency league as large scale. Efficiency, I'm sure you'll agree, is the root of conservation.

      So yeah. Put your energy into bullying the power companies into using greener technology.
    • IanCal, on 02/21/2008, -0/+2Wanna lift a 50lbs weight 4ft every time you want a dim bit of light for a minute or two? Go ahead.
  • int10h, on 02/21/2008, -4/+7I think gravity lamp is pretty cool guy. eh lasts 200 years and doesn't afraid of anything
  • itsgotyou, on 02/21/2008, -0/+7hey dude. it's your turn to replace the gravity in the stupid lamp.
  • fani, on 02/21/2008, -0/+1What happened to duggmirror ? Its just redirecting back to digg ? WTF ?
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