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Partially Self-Perpetuating Lamp

Reduces the drain on power grid by using its own heat to power itself.
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I saw the "Instructable" (linked) that explains how to use a thermoelectric generator to light an LED using wasted toaster heat, or charge a cell phone using excess heat from a car.

It seems all that is needed to create voltage is a heat differential from one side of the material to another. My idea is to create a lamp shade design integrating this material, which would absorb the excess heat from the bulb (inside the lampshade) and its "cool side" would be outside the lampshade, so a voltage would be created.

Then, this voltage could be used to supplement the lamp's power. Initially, I thought you may be able to unplug the lamp from the wall entirely, but with efficiency considerations and conservation, etc., that is really impossible. So basically, part of the power needed would be offset by this power-generating lampshade, and the lamp would become more energy-efficient.

Or, instead of being more energy efficient, you can use the additional power to make the lamp brighter by powering some LEDs or something like that.

The main technology needed would be a mechanism that could reduce the power pulled from the wall outlet when power was being generated by the thermoelectric lampshade. Of course, this could be extended to all devices that generate heat, such as toasters, ovens, and dryers. Recoup some of the lost heat and turn it into supplementary power for the device.

paix120, Apr 21 2009

DIY Thermoelectric Generator Instructable http://www.instruct...id/SX5TXOUFTK89XRF/
"Charge your cell phone using wasted heat" [paix120, Apr 21 2009]

Ugly Lampshade - Example http://www.dargate....248_images/1392.jpg
Of course this isn't the design I had in mind, but I think the narrow opening at the top would heat up the area with the metal ring, which could be our generator. [paix120, Apr 21 2009]

Thermoelectric Fan http://www.navitron...p?catID=67&proID=14
Not the link I was looking for ... [batou, Apr 21 2009]

[link]






       If the glass of the bulb was a perfect inwardly facing mirror would the light ever go out?   

       [21Q] Well if you thought of it, you didn't post it here :)   

       I had also thought of the solar panel idea, but incandescent light bulbs produce a different spectrum than the sun, so I think special panels would have to be made for them, and the small area at the base of a lamp doesn't seem to be enough square inches to generate enough power via photovoltaic means.   

       However, if I hold my hand over a light bulb, it gets very hot! From the Instructables demonstration, it seemed like the differential in temperature was what was needed. Bulbs are notorious for losing energy to heat, right? I don't know enough about the cost or efficency of the thermoelectric generator materials yet to determine whether it's cost-effective though.   

       This site is supposed to be for halfbaked ideas, right? I didn't exactly do a full market analysis before posting! Glad you found it intriguing, even though you already thought of it :)
paix120, Apr 21 2009
  

       [2fries] Not sure what you're getting at... you mean if we used a mirror/lens to focus the heat to the part of the lampshade collecting it?   

       I think if the bulb surface were an inwardly facing mirror, 1) it would probably catch on fire, and 2) you wouldn't get any light coming out so you wouldn't know if it were on or not! Is this an 'If a tree falls in the woods when no one is listening' response? :)
paix120, Apr 21 2009
  

       Also, keep in mind this idea is not only for lamps, but for any heat-creating appliance. I just really like the idea of capturing wasted energy, like regenerative brakes on cars.
paix120, Apr 21 2009
  

       Is it this time of year already?
loonquawl, Apr 21 2009
  

       Yes, it is. It's always that time of year. But this idea does recognize conservation of energy and efficiency.   

       If we could buy fabricated Peltier junction material by the foot like thin sheet metal, and at a similar cost, this might be rather feasible.
batou, Apr 21 2009
  

       //Is this an 'If a tree falls in the woods when no one is listening' response? :) //   

       Pretty much. : )   

       Whether heat can be efficiently captured and reused depends on the specific heat of the medium from which it is captured, because that will determine the heat loss to the surrounding ambience, and also the method by which that heat is converted back to electrical energy.   

       If it's water in a sealed container, sure-ish. If it's air, not really.
shapu, Apr 21 2009
  

       [shapu] - as far as I know, the heat in these devices doesn't need to be 'captured' - it's the gradient of being hot on one site one side of it, cooling through the material, to the cooler other side, that causes the voltage to be produced. As far as I'm aware, no heat needs to be stored.   

       [loon] Notice my use of 'partially' in the title. I know actual self-perpetuation is not possible, if that's what you're rolling your eyes about. This one just uses a lamp or appliance's heat to supplement its power needs.   

       [batou] I am fairly new here compared to some of you, so I don't know how often these types of ideas come up, but thanks for recognizing that I thought it through! I think it's feasible, too.   

       [21Q] Sometime when I have more time I will research the comparisons between photovoltaic and thermoelectric in terms of efficiency and cost.
paix120, Apr 21 2009
  

       [paix120] - I see - I misread the idea as being a lamp that would store excess heat as energy and then use it in place of the standard plug through some sort of switch from one to the other. So my anno is without value and your lamp is with...uhm...value. [+]
shapu, Apr 21 2009
  

       Thanks!
paix120, Apr 23 2009
  

       I am not convinced. If you want to build an energy-efficient lamp, first thing has to be to ensure most energy ends up creating visible light. -> LED. The losses in transforming low-heat back to electrical energy are really bad. Better use the heat for heating something (heating a passive-energy house, for instance)
loonquawl, Apr 23 2009
  

       Well i didn't say it was the BEST solution (a bulb that doesn't give off a ridiculous amount of its energy as heat is obviously better than incandescent), just an idea that I think could work :)
paix120, Apr 25 2009
  

       I guess I was bound to get some negative votes on one of my ideas sooner or later!
paix120, Apr 25 2009
  
      
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