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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.
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.
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!
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?
This device isn't powered by gravity, it's powered by people. Gravity only stores the energy for slow release, like a capacitor.