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Gravity Lamp Grabs Green Prize
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.
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.
I am Jack's complete lack of surprise.
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.
Vibrating sex toys that power themselves ?
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.
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!
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.
Don't disappoint your bird dog. Go to the range.
IANAE (that would be engineer) but I'm thinking that by adding resistance other than weight, like a spring, you would be able to increase the required energy input.
Without looking too deeply into the design of this lamp, I'm assuming that the weights take hours to drop, something like a grandfather clock's. A lot more energy would be absorbed than if the weights dropped freefall.
(I could be completely wrong here)
120 characters for a sig? That's bloody useless.
Wouldn't it be cool if one could reset the device simply by flipping it over (hourglass style), rather than having to use some mechanism to reset the weight to the top of the device?
Just a thought.
Huh?
you're thinking pure energy output by direct action - I think the poster was suggesting using a similar process to the one described by the lamp. 2 sets of 10 reps of 50lbs (for certain exercises) can be used to create a fairly decent source of potential energy for lighting. I figure...a single rep lifts weights about 18" - if this lamp is 6' tall...and it takes 10 5lb weights to power it from that height...
that's 4 reps to get the weights that high if attached to a ratcheting system. properly constructed, I bet I could get most of the electricity for my daily lighting by doing a fairly vigorous workout every day. It'll never happen, but only because of the weird stuff you'd have to have installed. I can picture it now - a huge stack of weights, lifted to the top of my house, 10 to 200lbs at a time, in 18" increments, the sounds ratcheting sounds echoing across the neighborhood. over the course of the day, they slowly grind down to the basement or ground floor. Run out too early? do another set! You've been meaning to tone those arms for a while now anyway, right?
You see, without that little doohicky, the universe stops.
http://propheteer.org
White LEDS are currently ~65 lm/W and will possibly soon be 150 lm/W http://en.wikipedia.org/wiki/Light-emitting_diode#Operational_parameters_and_efficiency so there is approx factor of 10 improved efficiency, so if the lamp can achieve 4W output he can match the 40W incandescent output. Even so this would require 57600J over 4 hours, which from a potential energy release from 1m would required a weight of 5000kg, so I think he fucked up his calculations or got a bit carried away.
Still, don't let science get in the way of art!
Ok First of all this device is not powered by gravity. It is powered by the human or machine that has to turn the lamp over to get it started. The human is the source of the energy ... the energy is being stored as potential energy (mass at a height) from the human.
Second, who (besides the inventor) would actually use a lamp that needs to be turned over every hour or four hours when you can just plug in a LED based lamp?
Conclusion: Green != Realistic
How about designing the entire lamp so it can stand on both ends?
Then you just lay it on the floor, and stand it back up again on the opposite end.
I guess maybe the rotors can only gear one way or something.
She was like chocolate when she drank... semi-sweet at first and then increasingly bitter.
Instead of having a 50 pound weight, why not have a much lower mass spring provide the equivalent pull?
A work that expires before its copyright never enters the public domain and thus enjoys eternal copyright protection.
The LEDs in products like this are either blue or UV LEDs coated with a phosphorous (not entirely unlike fluorescent bulbs).
Since this particular lamp emits too much blue, I would wager that it uses a blue indium-gallium-nitride LED.
Increasing the phosphorous coating would make the resulting color more yellow and thus negate any need to wait 15 years.
The most commonly used phosphorous emits in the 580nm range (yellow), while the blue diode itself emits light at around 470nm (blue, surprisingly).
The real issue is that so much power is wasted. A lot of energy is just dissipated for no reason around your home. That energy could be harnessed somewhat inefficiently but still cheaply and if it were done over time and as a matter of course the actual cost would be minimal. Of course, so would the benefits, but we all know such things add up.
I've heard about several households where a crap TV was hooked up to a bicycle-powered generator. Oh sure, the TV probably dies an early death due to brownouts, but the point is, kids in the house couldn't watch TV unless one of them was pedaling. So obviously you get enough power out of a bicycle to do work, if not useful work :)
If you can run a TV, you can certainly run a laptop. My Core Duo with a 17" widescreen peaks at 90W.
If you use the energy immediately (i.e. reducing grid use, not replacing it) then you can get every watt-hour of energy produced out of the system and actually use it. If you lived off-grid and you had a well-insulated peltier cooler-based fridge, an energy-efficient laptop, and a few LED lights, plus a composting, methane-producing toilet for handling waste and producing cooking gas, a small family could produce all the energy they needed from their food (and more!) and still have entertainment.
Of course, dropping $500 on a homebuilt wind generator and some electronics to go with it would probably do the job, too.
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
I dunno what crazy math you are doing but your calculations are way off. At 58" (1.47 m) the device will output 1.35 watts:
W = ( N * m ) / s
N = kg * ( m / s^2 )
N = 22.6 * 9.8 = 221.48
W = ( 221.48 * 1.47 ) / 240
W = 1.353
I also don't know WTF you're talking about 150 lumens / watt. Many white LEDs output 300 and up lumens / watt.
In short this is totally doable.
Give it a stand.
Set the stand on the floor, it has an arm that goes up to 50% of the height of the lamp and attaches to the back of the lamp. The lamp would be supported by the stand and wouldn't actually touch the floor. When the weight reaches the bottom, simply flip the lamp over by applying force to the upper portion. You could add in little catch or ratchet points so it would be easy to do.
Out of modpoints but really liked a post? 1BDkF6TtmmeZ3yqXbz9yhdYVqRYnwFoXDj
The first prize winner seems MUCH more interesting: An open-source design for an energy meter.
See here
Basically, he's gonna provide the design specs to build your own kill-a-watt
So, it's:
And no interest whatsoever on Slashdot? WTF?
Seems to be popular today - after all, if you limit contestants to operating within the laws of physics, you're just going to get more of the same old stuff! No matter that it can't ever be built and serves absolutely no practical purpose.
I think it was Popular Science (maybe Popular Mechanics) that had a safety product design contest after 9/11. One of the winning entries was a device the size of a tube of lipstick that was supposed to contain an absurd amount of compressed oxygen - something like 30 minutes worth - to help the user escape from a burning building. If only firefighters knew about this magic technology - they wouldn't have to lug around those bulky SCBA tanks anymore! Us SCUBA divers would be quite interested, too. An 8-inch long 'spare air' cylinder holds a whopping 1.7 cubic feet - something like 60 breaths.
I don't remember *any* of those winning designs being practical. The closest was a system for firefighters that would provide personnel tracking and 3D maps of buildings - no mention of who was supposed to gather that data for thousands of buildings and keep it up to date, though. Maybe someone can provide a link to the article.
For a magazine, it's understandable, if a bit insulting. For a university, it's kind of pathetic. If our education system was working, ANY high school graduate ought to be able to show how this lamp (or the oxygen cylinder) is totally unworkable, or at least realize that the numbers are off by a couple of orders of magnitude or more.
Hey I'm a pretentious draft mon . . . er, architect you insensitive clod! And it's true that there are lots of us with little or no technical experience. Lucky for me my undergrad was AE, and I have built a few buildings on my own. Because in the academic world of architecture you learn nothing of how to build, or even how to design stucturally sound buildings. But you do get a lot of pedantic critiques. So I've got that goin' for me. Which is nice.
This device isn't powered by gravity, it's powered by people. Gravity only stores the energy for slow release, like a capacitor.