Shop OBEX P1 Docs P2 Docs Learn Events
Heat Operated Lightning System — Parallax Forums

Heat Operated Lightning System

Tushar BotuwarTushar Botuwar Posts: 1
edited 2014-08-14 14:04 in General Discussion
Hello All,
I had requirement of Lightning System which should work on Heat from system.
There is furnace which is continuously heating at temp around 400 Degree Celsius,so i want to use the same heat in order to glow light in furnace.
At the same time i want light to be ON when door is close and to be OFF when door is closed.

If anyone having any idea on heat operated lighting system then please share.

Comments

  • LoopyBytelooseLoopyByteloose Posts: 12,537
    edited 2014-08-12 23:21
    I cannot figure out if you desire to generate electricity from heat or to have control devices monitor and control lighting in relationship to the heat output, or both.

    Or do you want to use the light from the furnace's heat source without conversion to electricity?

    There are PIR sensors that will sense and measure heat from a distance.

    Electrical generation from heat has traditionally been done by conversion to super-heated steam which drives turbines.

    I cannot seem to comprehen why one would want to add lighting inside a furnace regardless of whether the door is open or closed.

    Heat operated lighting systems.
    A. a candle
    B. a kerocene lantern.

    It doesn't require a whole furnace to generate a few watts of light.
  • prof_brainoprof_braino Posts: 4,313
    edited 2014-08-13 12:55
    Hello All,
    I had requirement of Lightning System which should work on Heat from system.
    There is furnace which is continuously heating at temp around 400 Degree Celsius,so i want to use the same heat in order to glow light in furnace.

    A furnace continuously at 400 C already has something glowing, doesn't it? Why not put a window to the chamber and use the light that already being produced?
  • Heater.Heater. Posts: 21,230
    edited 2014-08-13 13:20
    400C? My soldering iron does not glow at that temperature.

    Still, it's enough to boil water, make steam, drive a steam engine, to spin a generator to light the light.

    Whilst at the same time driving a pump to put some water, under pressure, back into that steam boiler which a can then make steam, drive the engine....

    After all that, detecting if the door is open or not should be trivial.
  • prof_brainoprof_braino Posts: 4,313
    edited 2014-08-13 13:23
    Heater. wrote: »
    400C? My soldering iron does not glow at that temperature.

    I mean, there's maybe fire in there somewhere right? he doesn't say what the heat source is, or how bright it needs to be.
  • Duane DegnDuane Degn Posts: 10,588
    edited 2014-08-13 14:05
    I think what Tushar is asking about is some sort of thermoelectric generator.

    You might be able to get enough energy from such a device to power a light. One problem with these generators (all generators using heat) is you also need a cold side to the generator. The cooler the furnace room is, the more power you can get from the thermoelectric generator. Using the thermodlectric generator would increase the amount of heat lost to the room.
  • ercoerco Posts: 20,256
    edited 2014-08-13 22:01
    Duane Degn wrote: »
    I think what Tushar is asking about is some sort of thermoelectric generator.

    My 1957-era gas floor furnace uses a thermopile to in the pilot light to generate 750 millivolts to keep the gas safety valve open. Basically a low-power solenoid keeps the valve open as long as the pilot light is on and heating the millivolt generator (AKA thermopile). If the pilot light goes out, the gas valve slams shut to turn off the gas supply as soon as it cools down (~a minute). I was always underwhelmed how little energy the thermopile put out. Never measured the current, but it must be pretty low. Your Wiki article also mentions low power output in the "limitations" section.

    Their typical efficiencies are around 5–8%.

    Possibly having a "cold" reservoir to route the heat to might raise the efficiency.

    http://www.homedepot.com/p/Honeywell-Replacement-Thermopile-Generator-750-Millivolt-CQ200A/203186986
  • jonesjones Posts: 281
    edited 2014-08-13 22:30
    OTOH, there's this: http://www.biolitestove.com/products/campstove/

    If you want a mechanical generator, forget the water/steam and use a Stirling engine.
  • ercoerco Posts: 20,256
    edited 2014-08-13 22:40
    Very cool, jones! Max 2W continuous at 5V sounds like ~400 mA. Not too shabby at all.

    If I were backpacking, I'd have to compare this to a solar cell on the top of my pack and see how much power I can collect vs how much I need, and factor weight in too.
  • WBA ConsultingWBA Consulting Posts: 2,934
    edited 2014-08-14 09:51
    erco wrote: »
    My 1957-era gas floor furnace uses a thermopile to in the pilot light to generate 750 millivolts to keep the gas safety valve open.

    Could you put a few thermopiles together and connect them to a Joule Thief circuit to power some sort of bulb?
  • mklrobomklrobo Posts: 420
    edited 2014-08-14 14:04
    Thermopiles are the way to go. Russians have used these in a standalone nuclear power generator, in isolated light houses
    in Siberia.:smile:
Sign In or Register to comment.