Introduction: Candle-Powered Electric Candle

Picture of Candle-Powered Electric Candle

After seeing news reports about Hurricane Sandy and hearing the ordeal that all of my family and friends in New York and New Jersey went through, it got me thinking about my own emergency preparedness. San Francisco - after all - sits atop some very active fault lines. As local geology fans always like to point out - statistically speaking - we are long overdue for a large quake.

This forecast is bad news for me, because I don't think that I am very prepared. I might have a few gallons of bottled water in the back closet, but I was ordered not to look in there until after Christmas... so... I am really not sure. Hopefully we will not have an earthquake before then. Anyhow, in the meantime, I have no real emergency supplies to speak of.

I have been thinking a lot lately about being more prepared, and what supplies we should have on hand for when the 'big one' hits. After prioritizing the three most obvious things to have in a severe emergency - water, food, and a fair-sized crowbar - it came down to figuring out what else one needs to survive. It did not take me very long to conclude this item was electric lighting. I use that all the time. How can I live without that?

After assessing the problem, it became apparent to me that after a few days of constant lighting, all of my batteries will be dead. This means that either I need rechargeable batteries, or a way to generate electricity without them. Not needing batteries to begin with seemed most sensible to me. I explored different options and finally figured out a low-cost, long-term, and portable, method to keep my electric candles lit.  I am going to use heat generated by tea lights. The nice thing about this solution is that they are dirt cheap, small, and will last forever. You can buy about 1,000,000 tea lights at Ikea for $1.99. With a fair-sized stock of small candles, I can keep my electric candle lit indefinitely. Thanks to my candle-powered electric candle, I know that I will never be left in the dark.

Do not leave this contraption unattended. Always have a fire extinguisher on-hand. This is probably less than ideal for normal day-to-day use.

Step 1: Go Get Stuff

Picture of Go Get Stuff

You will need:

(x1) electric candle
(x1) Peltier heat sink assembly
(x4) 12" x 3/16" aluminum rod
(x4) 3/16" shaft collars
(x1) candle

Step 2: Drill

Picture of Drill

Drill 3/16" holes in the corners of the larger "cool" heat sink. This is the heat sink that gets cold when electricity is applies to the module.

Make certain that the 3/16" rod will be able to be inserted through the hole, between the grooves, and out the other end.

Step 3: Attach Shaft Collars

Picture of Attach Shaft Collars

Slide the shaft collars about 3" to 4" up the aluminum rod and fasten them into place.

Step 4: Assemble

Picture of Assemble

Slide the aluminum rods through each of the corner holes, such that the heat sink is resting on the shaft collars, and the cool heat sink is facing up.

Adjust the height of the shaft collars until the bottom "hot" heat sink is elevated high enough off the table to allow you to place a candle comfortably underneath with about an inch of clearance (for the flame).

Trim away the excess aluminum rod material, such that all four are flush with the top of the "cool" heat sink.

Step 5: Wire It Up

Picture of Wire It Up

Connect the red wire from the peltier junction to the positive terminal on the candle. This is the terminal the little nipple on the battery normally touches.

Connect the black wire, the ground terminals where the flat side of the battery normally connects.

Step 6: Insulate

Picture of Insulate

Apply electrical tape (or insulator of choice) over each connection. This will keep the circuit from shorting out on the heat sink.

Step 7: Cover the Sensor

Picture of Cover the Sensor

Take a small piece of tissue and jam it into the candle's light sensor hole. This will make the candle believe it is always night time, and not wait until it is dark to turn on.

Step 8: Fire!

Picture of Fire!

Light your candle and place it below the "hot" heat sink. In a few minutes, the electric candle should light.

Adding an extra candle should speed up the amount of time it takes to glow.

If you blow out the candles, the electric candle will stay light until the heat sink cools off.

Do not leave this contraption unattended. Always have a fire extinguisher on-hand. This is probably less than ideal for normal day-to-day use.


JanD28 (author)2015-12-13

i'm in search for a peltier module to power a led light for cooking on a rocket stove, i shop at conrad for my Electronic stuff but there a lot of different models to choose from..

incognitony (author)JanD282016-02-28

Look for a Seebeck module. Like a Peltier but optimized for generating power instead of generating heat and cold temperature differentials.

SteveMann (author)2016-02-06

This is really a stroke of genius!

I love it.

Marvin Minsky (the inventor of the machine that does nothing but turn itself off every time it is turned on) would be proud!

Slime Eel (author)2015-09-04

Oh the irony.

kimvellore (author)2012-11-28

you could have the bottom made with a solid copper plate so it is a heat absorber and not a dissipator. If solid it can be placed on a heat source and absorb heat faster. Here is something similar

Bindlestiff (author)kimvellore2013-07-12

If I remember right, a good absorber is the same thing as a good dissipator. So the heat sink which dissipates heat well should do an equally good job of absorbing it.

mbainrot (author)Bindlestiff2014-01-26

Absorber/Dissipator are not quite the same in my comprehension (though the/my terminology might be wrong)

Absorber would be referring to how well heat is transferred into the material, as in its thermal conductivity.

Dissipation ability would be how easily it looses heat. This can be improved/worsened (depending on your point of view) by altering the thermal mass (how much material is present) and how much surface area is exposed to air/moving air.

This is why a tin lid works better for the hotside than a heatsink despite differing thermal qualities. The tin lid, has little thermal mass and sucks at dissipating heat under load (although looses it very easily due to its low thermal mass). On the other hand, the heatsink has a buttload of thermal mass compared to the tin lid, the reason the heatsink is not good though, is because, even under high-ish load, it can loose heat to the atmosphere far easier than the tin lid because of the emense amount of surface area which is arranged in a way that is able to "leak" heat to the atmosphere.

As such a lump of copper plate would prob cut the bread as would a tin lid. Copper would be better though or alternatively a moderately thick piece of metal such as aluminium, tin or steel.

mbainrot (author)mbainrot2014-01-26

And here is a bonus tidbit :)

Not only do you have to concern yourself with thermal losses via convection (air stealing and mollesting your precious heat), but you also get radiative losses (i.e. heat loss due to thermal radiation in the infrared spectrum).

Whilst in my experiments making this do something very useful are not very fruitful thus far... I know it's been done successfully. NASA has a probe out there somewhere that is using a depleted uranium heatsource and the bone chilling cold of space via a thermo-electric cooler. It produces some voltage (i don't remember :$) and around 200-300 watts. Whilst that is a buttload of power, remember that the hotside is prob 40-60C maybe cooler, maybe hotter and the cold side is around -250C or lower.

bob3030 (author)2013-09-19

Hey, aren't you the guy that designed the gas engine that generates electric power for the Chevy Volt?

goodforcatfish (author)2013-01-20

Why didn't I think of that? Excellent and simple idea; props to you sir. I'm going to start on mine after this post!

paulmcarthur (author)2012-12-30

that is a great idea,how much electricity does it generate?

TheAmateurArtisan (author)2012-12-14

Props for being mentioned on adult swim.

Really? When was this mentioned on Adult Swim...?

dworley (author)randofo2012-12-25

Congratulations, that's almost as cool as the Pixies thing.

Also I've been wondering what that thing is on your desk. Now I know it's a recursive redundancy machine.

those black card bits of humor between ads that show up, telling you random bits of current events. they mentioned an electric candle powered by a real one while they were browsing the internet.

crazyg (author)2012-12-17

cool or hot even.nice one, but now confusing the fan sealed on both sinks? or is there a pass through for air,doesnt look like it,my intuition says it dont work,but it clearly does. imagining convection currents of air going round in circles what goes up must come down. am presuming its a regular motor fan.tempted to make one sure it would work but how! i think i have a similar heatsink from a mini fridge in the shed somewhere buried, its december and its old out there.let me know so i can get on with this 35 to medium format camera conversion.

technovative (author)crazyg2012-12-22

What looks like a brushless fan between the two heatsinks is actually the Peltier, or TEC module surrounded by black foam weatherstripping insulation. The module is what generates electric current when there is a temperature difference between the two sides. These modules will also heat up on one side and get cold on the other when electric current is applied to them.

crazyg (author)crazyg2012-12-17


veeguy (author)2012-12-20

I think this would be *great* for the functioning mechanism for some sort of Rube Goldbergesque Steampunk inspired lantern. Lots of brass, a small hinged door to insert and light the candle, a large round lens with a brass guard protecting it, perhaps even a small chimney to vent excess heat. I'll put this on my project list, but perhaps someone with more time than I could turn one out quicker. (PS.- these Peltier type devices can be sourced cheaply by taking apart 12 volt car or home refridgerators typically available at garage/rummage sales for $5.- to $10.- .)

Kilo_Foxtrot (author)2012-12-13

This is exactly how the Mars Rover is powered, it has a tiny nuclear reactor producing the required amount of heat.

thealeks (author)2012-12-11

This makes me think of an electric bike i read about that to charge the battery you have to pedal a charger unit. I like the ingenuity though. You dont see alot of heat powered projects. You could power a variety of small devices with this.

paxmanmerv (author)2012-12-03

Thats real sweet!
Gotta have a go at this.

pdub77 (author)2012-12-02


spylock (author)2012-11-26

The only way I see this being a half way practical way of lighting would be to place it on a wood heater,something that you have to use anyway.I think you could modify it.

spylock (author)spylock2012-11-26

No reason to pick on the guy,Ive seen stuff on here far worse than this idea,and this idea may prompt someone to make an improvement,or use it for something different.

belsey (author)spylock2012-11-26

Don't you think the futility is part of what makes it so beautiful?

theawesomeninja (author)belsey2012-11-26

Or not... It's using energy otherwise wasted as heat to create more light (So it actually is helping!) so it's actually increasing efficiency (assuming you're trying to make more light)

belsey (author)theawesomeninja2012-11-26

Theoretically -- though the heat sink does block the candle flame from view, diminishing some of the visible light, and I doubt if the tiny flickering LED makes up all those lost lumen. But regardless of whether it's actually a loss, or a wash, or a gain in energy, visually it seems futile, and invites the question: how far have we really progressed since we mastered fire?

zorcy (author)belsey2012-11-27

at eye level, the light from the candle still travels sideways. The light that would be lost going up, is converted to light in all directions. There is no perpetual machine, so you have to loose some. This is still a better recovery of lost light and heat to light again. The light would be wasted up, radiant heat converted to regular heat. The heat from the fire would be wasted up, converted to convection with reclaimed radiant heat. Since it would have been lost, we can conserve some. The only downfall, is the light is not directed. It would be more efficient if there was a reflector on the candle and the "flame" LED was a regular LED with a focusing reflector. Both pointing in the same direction.

All-in-all, a very simple method to show physics, conservation and convection to a class. It should spark some ideas of recycling old computer parts.

spylock (author)zorcy2012-11-27

I think he or she would have been better off to have made something like a stove fan.It generates power from an existing heat source,like a wood stove,and recirculates air.The heat sink is the major part in making one,and they sell for around $130.00;I can say that this idea is by no means the worse thing I have seen on here.To me,if nothing else its looks are pleasing to the eye,maybe its just me though.

bryan3141 (author)spylock2012-11-28

Heat sink for $130? I'll tell you what, I'll sell you all the heat sinks you want equivalent to the one he used for $100 a piece! Shipping included. Think of how much you're saving!

spylock (author)bryan31412012-11-28

Im just saying,thats what the fans sell for retail,and a person could make one with that much heat sink,a piece of copper about a foot square for the fan blade,two if the base is going to be copper,two small bearings with a metal rod to fit,a few screws,and thats about it.

bryan3141 (author)spylock2012-11-28

In what universe? just with a casual peek. Or you can buy the whole assembly like this guy did (inlcuding a link) for $32 including the junction. Where are you getting $130? $30, yes, but $130? Like I said, can I be your supplier, please?

spylock (author)bryan31412012-11-29

Oh,and the sarcasm is uncalled for,Im not acting like a jerk,no reason for you to.

bryan3141 (author)spylock2012-11-29

i'm sorry for the sarcasm...and you owe me a BIG putdown because apparently I can't read....I couch certain things in humor when I shouldn't and I missed that you were talking about a really amazing bit of camping gear, not the actual project in question....that said, I've wanted one of THOSE for a while now, I just can't justify it as I don't do enough backwoods/off stream camping.

spylock (author)bryan31412012-11-30

Are you sure we are talking about the same fan?I can say one thing, if we are,and thats that I would never dish out that kinda cash for one,they dont look that hard to make.

bryan3141 (author)spylock2012-11-30

It's actually less a fan and more a high efficiency backpacking stove that uses local burnables to rapidly produce boiling water to reconstitute dehydrated food and beverages...the fact that it also produces enough electricity to recharge your iPhone is a BIG bonus as long as it stays within weight and volume limits. It's serious back woods gear. As I said, it's not significantly more expensive than the ones that are just a boiler.

bryan3141 (author)bryan31412012-11-30

here's a review of one...and it's not as nice, just as a boiler, as the one we're both talking about:

spylock (author)bryan31412012-12-01

I have thermos like that,its older but works well,you can burn about anything you can get in it,and it heats the thermos in no time.But now Im not sure youve seen the fan I mentioned earlier The Ecofan.I thought they were just at the Sportsman's Guide,but they are all over the net.

spylock (author)bryan31412012-11-29

Thats a totally different fan from the one Im talking about.If you go to Sportsman's Guide,and type in Ecafan Airmax Stove Fan then youll see the one Im talking about.They are 149.99 for nonmembers,and 134.99 for members.

bryan3141 (author)spylock2012-11-29

A followup, those things aren't actually significantly more expensive, maybe even less expensive than just the twig-fueled boilers that I ALSO can't justify at my current camping levels.

spylock (author)bryan31412012-11-30 I tried to give you a link,but I cant always do it,Im self taught on the computer,and my teacher didnt know what hell he was doing.

bryan3141 (author)spylock2012-11-30

Ok, now I'm TOTALLY confused. At this point I'm suspecting I responded to the wrong comment at some point. *scratches his head* I thought I was responding to someone who was quoting a really silly price on just a heat sink and it turned out he was talking about a boiler that uses the same tech to produce power to run a USB charger...for not much more than a simple kelly kettle on its own.

The circulation fan you pointed at seems like a worth while thing if you have an off grid cabin...and it's not horribly expensive for what it is, though.

spylock (author)bryan31412012-11-30

No its the right comment,I got confused when you said something about a boiler of some type,and now Im curious as to what kinda boiler you were talking about.Im sure youve seen the fan,and dont you think it would be easy to make?Also tell me about the boiler thing,and where I can see it,if you will.Oh and you said earlier in a comment that you were not to heavy into camping,looking at your photo,Id have bet that you were.

bryan3141 (author)spylock2012-11-30

A kelly kettle is basically a water jacketed chimney on top of a small burn chamber (see which doesn't cost that much less than the biolite stove referenced earlier (
The fan is very interesting and conceptually easy, but I suspect that that enormous cast aluminum heat sink is actually essential because peltier junctions don't really like extreme heat all that much. Maybe you could use a long piece of metal hanging off the side or front of the stove and get by with a smaller heat sink up top. It sounds like fun to find out! Unfortunately, I don't have access to a wood burning stove, so it's not an immediate project for me at least.

bryan3141 (author)bryan31412012-11-30

umm...I was meaning to reference just beyond the ( in the post above.

spylock (author)belsey2012-11-27

I think it could stand on its own as a piece of art,but with a few adjustments,it could become a more useful item.
As a candle,like I said,if one has a heat source that theyre using anyway,then the candle will be efficient to some degree.Any items worth or beauty,is in the eye of the beholder.I think there is something cool about it,I dont think it deserves all the ribbing its getting.

tiber (author)2012-11-29

OK this is ridiculously awesome. Not because of the YO DAWG factor but because I own a woodstove. Now I can power my fan (to blow the warm air) from the stove itself and maybe a few lights just by tossing them on the stovetop.

jrjohnwood (author)2012-11-28

Rube Goldberg would have loved this.

WailinSoul (author)2012-11-27

Very nice, maybe next time a wind powered fan?

About This Instructable




Bio: My name is Randy and I founded the Instructables Design Studio. I'm also the author of the books 'Simple Bots,' and '62 Projects to ... More »
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