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A Thermoelectric generator powered by a tealight. It started as an experiment of how much power I could get from one candle. But I liked the idea and it worked really well so I built this electric-mechanical ornament. I did not use a high temperature TEG-module, but instead a cheap TEC-module. That can still handle 200 degrees Celsius which is good enough.

Please see my other project with a more powerful TEG:
http://www.instructables.com/id/Battery-Charger-Powered-by-Fire/

Or how to create a self regulated thermoelectric CPU-cooler:
http://www.instructables.com/id/Portable-Airflow-Companion/

Concept:
It is also called a peltier element and when you use it as a generator it's called seebeck effect. You have one hot side and one cold. The module generates power to drive a motor and the motor fan/air flow will cool the upper heat sink. Higher temperature difference => increased output power => increased motor RPM => increased air flow => increased temperature difference and so on. The airflow will spread the heat into your room, which is the purpose of this construction.
http://en.wikipedia.org/wiki/Thermoelectric_effect

If you unmounts the basement you could also use it as a stove-fan or move air from other heat sources. The motor start to turn at about 15 degrees difference, which to my surprise worked when I just went outdoors with it and the upper heat sink got cooler than the basement. You can place it in hot water, on an ice cube, a pizza and it works just as fine.

Total cost was about 50€ (incl. shipping costs). I used some spare parts but I bought most of it.

Components used:
• CPU-cooler (cold side): Zalman CNPS5X (Base plate: 33x33mm)
• CPU-cooler (hot side): From an old PC (WxLxH=78x63x67mm)
• TEC-module: TEC1-07110T200 (30x30x3.3mm)
• DC Motor: 1,5-3V
• USB-fan (metal, only needed the fan)
• Thermal paste: Arctic MX-4
• A piece of wood
• Two pull springs
• Four M4 bolts and two M3 bolts
• Aluminum tubes (optional)

TEC specification (at ΔT=68C):
Vmax: 8.5
Imax: 10
Qmax: 52.7
Tmax: 200 degrees Celsius
Source: http://www.termo-gen.com

Construction:
First of all, it does not need to be exactly those components. Other heat sinks, TEC/TEG, motor, fan, thermal paste, bolts and base plate can be used. Main concept rules are:

  • A TEC or TEG module (smaller dimension than upper heat sink base plate). Specifications are not that important but make sure it can handle high temperature. Many modules are only 100 degrees C and then you need to modify the construction as it gets warmer than that.
  • One hot side that is not hotter than TEC max-temp (My candle flame never touches the surface)
  • One cold side, an efficient heat sink (heat pipes) are a good choice
  • Good thermal paste to maximize temperature difference
  • Low voltage motor, around 1V. I prefer it to be quite (low dB)
  • Fan with high air flow at low RPM
  • Base plate that adds stability, holder for light, isolate heat

The lower heat sink (hot side) was cut and polished to get it nice looking. I kept 5mm of the fins to absorb the heat well when the light flame burns and increases distance to the surface. New dimensions are 78x63x15mm. 4 holes are drilled through the heat sink and threaded as M4. 4 bolts will hold the lower heat sink on top of a wooden platform. Bolts go through the platform from below, covered with aluminum pipes for a better looking design and are screwed into the heat sink. The distance between wood and heat sink is 35mm but I would make it 40-45mm as the flame almost touches the surface. You don´t want that because it creates black soot. The lower heat sink gets really warm but at the same time it works as a cooler to not get TOO warm, that would melt the TEG-module.

Two springs attached to M3 bolts fixate the upper heat sink on the lower, with TEC-module and thermal paste in between. Both surfaces of the TEC are covered with a thin smooth layer of thermal paste. The springs adds pressure as well as isolate the heat to travel to the cold side. The upper heat sink could also be screwed into the lower heat sink but then you need isolated screws.

The TEC is directly attached/soldered to the motor and the motor is attached to the upper heat sink by another small piece of metal and a cable tie. The fan is attached to the motor with a small belt wheel and glue.

Result:
I think the hot aluminum part get to about 100-150 Celsius, I measured the temp with a grill thermometer covered in thermal paste but can´t tell how accurate it was. I measured 0.4V and 0.25A with one candle and 0.67V and 0.54A with two. That results in 0.1W resp. 0.36W output power. The efficiency to produce electricity this way is not that impressive though. A candle produce about 25 Watts, that means 0.7% efficiency.. But who cares, everything this machine does will eventually end up in heat any way =) That is a bit interesting, you increase the room-heating speed (I think) but looses nothing..

It is a bit noisy to have running all the time. To find the optimal motor/fan => airflow/noise level will require some more experimenting.

Mod Proposals:

  • Skip the base platform and bolts and use it as a stove-fan.
  • Use two/four TECs side-by-side to multiply output power. Add a 5-10mm thick copper plate that covers all modules and then place the CPU-cooler on top of that.
  • Use a brushless DC motor and a suitable fan to make it noiseless.
  • Build in a slow motor beneath the platform to make the whole thing spin 360 degrees.
  • Put wheels on the platform.

Edit:
I have changed the motor to a "Tamiya 76005 Solar Motor 02 (Mabuchi RF-500TB)". Got it on Ebay. It´s incredibly strong at low RPM and I give it only 0.5V. A very good motor, but best of all, it´s quiet! I cannot hear it at 2m distance at full speed. It also gives stronger air flow. Now I can run it all time =)

<p>Verry fun to copy your idear, hope you dont mind me doing so.</p>
Hello <br>I am paresh katariya <br>I am final year Engineering student<br>This topic Thermoelectric Fan Powered by a Candle my project <br><br><br>Please information me this topic <br><br>Email :-<br>pareshkatariya033@gmail.com
<p>Hello pareshkatariya.</p><p>tell me what you want to know and i do my best to inform you...</p><p>Peter.</p>
<p>Hello, so I wanted to do this for my science fair experiment, but I am a little confused. Did you install a separate motor and fan, or did you just use the fan and motor that came with that?? -&gt;&gt;http://www.newegg.com/Product/Product.aspx?Item=N82E16835118128</p>
<p>the solar motor is bought on ebay, the fan is from a pc, cooler fan...glued them together... the peltier is also from ebay....</p>
Absolutely not. Really nice build you got there! Old fashion style.
Some more images.
<p>this is real wondful......where to buy this module? Except the TEC(we have in manufacture), i need the sink and fan, i also wanna try !</p>
<p>Together with my other instructable and with the new fan.</p>
<p>nice</p>
<p>can any upload the video of connection of this components</p>
This was absolutely amazing to me thank you for the Post. It's completely official I'm a dumbass thank you counselor.
<p>Thanks for taking the time to document your project. I found your parts list invaluable. Here's a few pics of mine.</p>
Tks for infomation..me to made it but waiting for fan motor
<p>So, I created the fan but I have a question, could I power the fan with any other heat source, and if so, what could I use?</p>
You know, you could really get that motor to crank if you used a can of ethonal gel. The stuff used for heating buffet trays. <br> ________<br> ______[________]______<br> [ Ethanol Gel ]<br> [ Buffet Heater ]<br> [_____________________]
<p>i made this project &amp; successfull</p>
<p>I finally made one. Not impressed with my fan blades or how I mounted the motor. But it works.</p>
Nice
<p>can i buy it? pls, i need it asap! D: </p>
Sorry, not for sale. I'm glad you like it:)
<p>Wow, you got 10A from that TEG?</p>
<p>I finally made one. Not impressed with my fan blades or how I mounted the motor. But it works.</p>
<p>Hi all, I'm trying with a TEC1-12706 and a Cooler Master Hyper 212, but I can manage no more than 0.4 volts from the peltier. Any help please? </p><p>Peltier: <a href="http://www.dx.com/p/tec1-12706-semiconductor-thermoelectric-cooler-peltier-white-157283#.Vmx7MrjhDIU" rel="nofollow">http://www.dx.com/p/tec1-12706-semiconductor-therm...</a></p><p>Cooler Master: http://www.amazon.es/gp/product/B0068OI7T8?psc=1&amp;redirect=true&amp;ref_=oh_aui_detailpage_o00_s00</p>
<p>how would it go if you mounted a small wind generator behind the cooling fins to charge small batteries using a joule thief </p>
<p>This may be a silly question but in theory if I had a rack of these outside in a very hot environment could they power an appliance of appreciable size? Also, an awesome Ible, will make when I can.</p>
They must also be cooled with something.
<p>hey there, nice job. please is there a way i could get the theoretical analysis of the heat transfer between the candle and the metal plate in contact with it. oluwasubie@gmail.com</p>
<p>nice..</p>
This would be so cool if you could use the heat produced from a CPU to power a fan to then cool it? Would make a completely self contained cooling system that would continue running when your computer has stopped, until your system has cooled back down! <br> <br>Unfortunately my guess is that this is not possible because the CPU would overheat and die before it produced enough energy to turn the fan? <br> <br>Is it possible to get more sensitive pads to generate energy quicker?
A friend and I built this very efficient Thermoelectric Generator for $7.50.<br>It can generate power from a temperature gradient of 5 degrees celsius or greater and can withstand up to 300 degrees celsius before shutting down.<br><br>http://instructables.com/id/Recycled-Energy-ThermoElectric-Generator/<br><br><br> Please vote for our entry in the instructables contests!<br><br>Have a great day!
<p>You can not generate the power you need if your heat source needs to be cooled down.</p>
Did you not see my comment or do you not believe I actually built and tested that? Maybe you can't cool it down as much as you can with a externally powered fan but you can deffinetely cool it to some degree and make it survive. Just a portion of the heat energy is enough to increase the cooling efficiency compared to a passive system.
<p>It is possible it seems, I build one myself:<br>http://www.instructables.com/id/Portable-Airflow-Companion/</p>
If I'm not mistaken I think it's Coolermaster that has at least made a concept product of that exact idea. I would be interested in knowing how well it works. Probably only good enough for casual use, not gaming or anything. Though I know some gamers have used a peltier element by running electricity through it, with the cold side on the CPU, and the hot side against a cooling water block. Unfortunately, while it does make the CPU cold, a water cooling system is necessary because it produces even more heat in addition to that of the CPU
I have been thinking about it and discussed it in another forum but it would probably burn up yes, but I hope someone will try it for real! There is research going on to create better materials but there are no magical peltier yet I think. You can of course place many of them in parallel to increase the heat transfer.
<p>can i get the report of this project....i am doing thermal power engineering and i want to make this project...kindly send me the report at hamayun_toor@outlook.com</p>
<p>Hello sir,</p><p> I want to make this project (fan driven by candle power ). Can you suggest me from where i can get all the desire items.</p><p> Can you give me the entire procedure for assembling the items &amp; relevant images &amp; entire paper work like report for the same .</p><p> plz give me your email id for further contact.</p>
<p>Hello sir,</p><p> I want to make this project (fan driven by candle power ). Can you suggest me from where i can get all the desire items.</p><p> Can you give me the entire procedure for assembling the items &amp; relevant images &amp; entire paper work like report for the same .</p><p> plz give me your email id for further contact.</p>
<p>Dear Joohannson, first of all great job!!!</p><p>I'm about to build a similar version of your model but i wanted to connect multiple fans (i recently got a considerably powerful TEG - 21W, 7.2v) to the power source.<br>I'm studying fine arts so my basic knowledge of wiring and electronics is almost non-existent, thus please excuse the dumbness of my questions!</p><p>- You mention the use of a DC motor: could i, for example, avoid it and connect the pc fans' cables directly to the TEG? If yes, what about the yellow (ground?) cable?</p><p>- Should i wire them in parallel or serial?</p><p>thanks in advance!</p>
I don't think your pc fans will run because they are 12V and your teg is max 7V.
<p>hi, this is what i have build. it is ugly and heavy, but it works. i used 4 cheap chinese TEC1-12706 modules in row and a Shirakawa Micro Motor that runs at 0,3-1,5V. there is no reason bothering with expensive TEG's in this construction, because of the 10mm copper the heat on the hot side doesnt even reach 80&deg;C, even with 2 candles. there is no reason to bother with more than 1 candle either, because the difference between cold and hot side is in any case after a few minutes only about 20&deg;C. I tryed to improve it as much as possible, but the best way would be to build it vertically to have less Problems with heat on the cold side. the Switch you can see in the Pictures is to control the Ultra low voltage step up DC/DC Converter with energy harvesting Management and some other stuff I build in. it simply Switches between running &quot;normaly&quot; without electronics and &quot;running automaticly&quot;. running automaticly means in this case that this <a href="http://www.linear.com/produkt/LTC3105" rel="nofollow">http://www.linear.com/produkt/LTC3105</a> starts running and charges a 2,7V 10F super cap over energy harvesting Outputs wich autmatically gets used whenever the Input current reaches a specifyed lowpoint (0,3V) for a few seconds (20s) to give a short cooling boost at Maximum fan power... I had to do this, because when my candle burned down to a certain Point, the fan stoped running wich pissed me off and this way it keeps running till near the end of the candle. I might put up some other fan blades maybe, because the native ones from the arctic freezer I'm using dont move enoug air at such low rpm, maybe it runs better then and even produces a useable tiny amount of energy .</p>
Nice work!
<p>sir where do i can get cpu-cooler hotside send me link about that</p>
<p>sir where do i can get cpu-cooler hotside send me link about that</p>
<p>sir where do i can get cpu-cooler hotside send me link about that</p>
<p>sir where do i can get cpu-cooler hotside send me link about that</p>
<p>sir where do i can get cpu-cooler hotside send me link about that</p>

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Bio: I like to design, construct and experiment with both old and new technology, especially when it includes mechatronics. I'm also devoted to photography, computers ... More »
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