Soda Can Heater

Have any of you seen the You-Tube videos on soda can heaters, or the how-to instructions to make one in the Mother Earth News Magazine?  We did, and since we will try just about anything, we decided to make one.

When we told people what we were doing, of course most of them thought we were crazy (not the first time) and had just come up with another hair-brained idea.  But when we told them to go to You-Tube and search for soda can heaters, they would come back later and say things like “sheesh, it just might work” or “wow, that’s really interesting”.  But most people still thought we were crazy.    😉

It took a while to gather up enough soda cans to use.  You know how easy it is to crush the can in your hand once that last drop of soda slides down your throat, kind of like stating “all done” in a more adult way?  Well, we had to break ourselves of that habit because you really need to use non-crushed soda cans for this project.  Once we had gathered enough cans (thanks Barry and Stephen for donating to our cause) we were able to begin the planning stages of our heater.  By this time we had watched at least four hundred and seventy one videos (not exaggerating – well, maybe a little) on soda can heaters and were therefore mildly confused as to which method we would use, so we decided to wing it and devise our own hybrid heater.  So….. off to the local box store to buy some Plexiglas.  We figured that the size of the Plexiglas would be what dictates the size of the box we would build and then fit the soda cans into it.  Unfortunately, we didn’t listen to one of the instructional videos as well as we should have, which states that the Plexiglas can actually MELT in one of these heaters!

So, we built a box from 1 x 4’s with backing to fit to the Plexiglas and lined the entire box (except for the front) with some extra Styrofoam we had laying around.  The soda cans were fitted into the box and we found they fit almost perfect.  Ray drilled holes in the bottom of each can (not easy to do) with corresponding holes drilled into the bottom of the box and through the bottom Styrofoam, and also into the top of the box.  Next, we glued the cans together bottom to top, bottom to top.  This is also easier said than done.  The glue we thought would work didn’t stick as well as we had hoped, so we spent an extra day re-gluing the cans into stacks of nine .  Then the stacks of cans were painted black.  A word of caution here – that paint stinks – especially when the heater is working!  Perhaps we should have used some kind of high temp paint instead of the cheap flat black, but since this was just an experiment, we figure we can learn from our mistakes.  The Styrofoam was wrapped in aluminum foil and then the can stacks were glued into place.  Ray temporarily placed the Plexiglas covering over the front and – voila – we were in business!

  • The Box The Box This is the box built out of 1 x 4's, using a piece of cement board we had laying around for the back. The box was sized to fit a piece of plexiglas over the top.
  • Drilling Holes into Cans Drilling Holes into Cans This wasn't easy to do, but Ray discovered that if he put the can in one of those squishy can holders, the vice would hold the can in place without squishing it.
  • Holes Holes Holes corresponding to the can holes were drilled into the bottom of the box for the cold air to come in, and then more holes were drilled into the top of the box for the hot air to go out.
  • Gluing the cans together Gluing the cans together Not an easy task. We found the grooves in the back of the truck worked well to corral the cans into a straight line. It would probably be a good idea in the future to do more research into what glue would work best for aluminumum, not only for keeping them together, but also for the off-gassing.
  • Styrofoam covered with foil Styrofoam covered with foil We covered the Styrofoam with aluminum foil as a reflective surface and to also help seal it. Not sure it was necessary, but it did make the whole thing look a lot nicer. 😉
  • Trial fitting Trial fitting When all the pieces and parts were pretty much done, we did a trial fitting - just to make sure! Luckily everything fit together pretty well!
  • Painting Cans Painting Cans Probably the easiest job - one we should have thought more about, however. Once the heater was installed, the smell of the paint for the first few days was ghastly! For future reference, we will probably use the high temperature spray paint.
  • Our Version Our Version So this is what the whole thing looked like when we were finished. Not bad, huh?
  • Installed Installed Ray attached aluminum ducting to the top of the box to route the air into one pipe, wrapped it with foam insulation, and then installed it into the kitchen window of our trailer. It works ! It doesn't heat the whole trailer toasty hot as it's a bit too small. It may work better if we attached a solar run fan on it. Happily our pipes don't freeze anymore!


Our first testing came on a cold but sunny January day.  As you can see from the results in the pictures, the inside temperature got up to 160 degrees before our thermostat conked out!  Holy cannoli, this thing really works.

  • Testing the heater Testing the heater Now it was time to see if this thing works! We had an indoor/outdoor thermometer, so we placed the indoor part behind the heater in the shade, as you can see, and put the outdoor part on top of the heater where the holes let the heat out. We did the test on a cold yet sunny January day.
  • 10:38 10:38 We didn't get the first picture soon enough! Within three minutes the temperature inside the heater had already risen to 71 degrees! You can see that the outdoor temp was 45 degrees and the time was 10:38.
  • 10:41 10:41 Three minutes later and now the temperature is 104! That's the temperature of my hot tub! The outside temp is now 47.
  • 10:45 10:45 Sheesh - One hundred thirty two degrees!
  • 10:48 10:48 Another three minutes, another fourty degrees! Wow, this thing is crazy! You can see the outside temp is also going up a little, now 49 degrees. We suppose that was because of the reflective heat from the concrete and the can heater.
  • 10:52 10:52 Wow. A full one hundred and five degrees HIGHER than the outside temperature! How's that for making heat from the sun!
  • 10:53 10:53 This was the last shot we got because the next minute the thermometer went kaput! Too hot! Wow, we can't wait to tweak our design just a bit having learned from our lessons and make a larger, more efficient one. We may even build a permanent one of these for our house! After all, it's free heat!

We can’t wait to make another bigger, better and prettier one!


Shared at:  Frugally Sustainable – Frugal Ways, Sustainable Days Blog Hop , Simple Lives Thursday and Homeacre Hop, Feature Friday Free-For-All, Farmgirl Friday, Show and Tell Saturdays, Common Sense Preparedness

Too Much Time On My Hands
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21 thoughts on “Soda Can Heater

  1. That’s amazing. Good job. I can’t wait to come and see all of these projects at work. I’m so proud of the both of you. Now we now where to go when this whole country goes to pot. Just kidding.

    • Lisa, you are welcome to come up anytime Ray and I are up there. It’s not hard to find us, just be prepared for a few potholes (um – craters) on the road to get to our property!

  2. It’s amazing how such a simple idea can be so effective. Great job building it Ray and to Vickie for documenting the project so well.

    • Thanks, Tess. Yes, it was just like being back in middle school! Too bad this doesn’t become more mainstream so that everyone has one of these on their homes! Even if it didn’t work every day during the winter months (and it won’t on cloudy days) think of all the energy this could save!

    • There are holes in the bottom of the box. Air moves from outside, through the holes, up through the cans (which heat the air) then up through the top of the box into your house through a window. Some people make permanent openings into their houses for entrance of the hot air from the box. You can modify the top of the box to fit exactly into your window, or use some type of ducting or tubing to get the hot air from the box into the house. Since we didn’t think that far ahead when we were making our box, we used a lot of insulation around the ducting so that it made an airtight seal through the window. When you look at the picture with the soda can heater installed in our trailer window, that’s what all the ugly stuff is that is at the top of the box going into the window. The next one we make will be sized exactly for the window with a little bit of weatherseal around it to make an airtight seal from the box top to inside the window. It pretty much heats our entire trailer, though that’s not such a big space, about 10-20 degrees. Enough so that on a really cold day but when the sun is shining, we don’t need to use the propane heater very much! The one we built was just a prototype and test, therefore we didn’t build it very big. Also, it would heat our trailer much better if we had a fan on it. Right now all the heat enters the trailer solely by convection (hot air rises). A lot of people use solar fans without batteries because the soda can heater can only work when the sun is shining, negating the need for a fan when it is not. Hope this info helps!

  3. What an intriguing idea – marvelous way to recycle and to make something very functional! Love it! I do appreciate you sharing with Home and Garden Thursday,

    • Yes, this actually is functional! We knew it would work before we made it just because of our high school physics classes – heat rises. But we were surprised at how hot it really got! This is a great DIY project because it can be made with things just lying around. Some people make them out of old windows! Thanks for your kind words. Vickie

  4. Thank you for linking to the Common Sense Preparedness link up. I’ve shared your post on FB and on my Pinterest boards. I’d just like to note that the way you have your images displayed, I can’t get a thumbnail to properly display on FB when I shared your post.

  5. Kind’ve curious. How long does the heat last once the sun goes down? Does it still radiate and put a fair amount of heat even after the sun has set or does it disipate fairly quickly?

    • Actually, it dissipates pretty quickly. Once the sun isn’t hitting it, it doesn’t make any heat. The good thing is that it doesn’t “leak” cold air into the trailer because cold air sinks and hot air rises. If the air is warmer in the trailer, then the warmth itself kind of prevents cold air from coming in. If it is colder in the trailer than outside, then yes, heat will rise from inside the soda can heater (even without sun hitting the soda can heater) into the trailer. Sounds kind of strange, but that’s the law of physics! So – for a wrap-up – you need the sun (or a warmer outside temperature) for the soda can heater to work. That being said, I have heard of people shunting air ducts through concrete from the heater, before it gets into the airspace. The concrete acts as a massive heat sink, absorbing heat while the soda can heater is working, and then will radiate heat for hours after the sun has gone down! I hope this answers your question, Katie!

  6. I just saw this post!
    I’ve always wanted to do this… We live in an old city house, with the basement (a poorly insulated one, at that) sticking up about four feet above ground level… so it’s always FREEZING down there, which means it’s always freezing on the first floor, too. I though adding some free heat to the basement would help warm things up! 🙂

    • This works amazingly well – but only when the sun is shining! I hope you try it. It doesn’t cost very much to build and there are so many variations to the design out there on the internet! One thing though – to make this more efficient, we are planning to add a solar run fan, which will push more air through. Have fun! If you make one – write a post on it and I can reference to it on my blog! Thanks!

  7. Do you know of anyone that would be able to come to a home and give ideas of how to set up a home in order to get the best use of the land and how to set things up and where the best areas are to set up a garden or a water catch system, etc. I am a single mom with no experience in any of this and feel the need to begin to be more self sufficient and need guidance without having to spend hours reading hundreds of books or websites on how to do and set up everything. TIA

    • Sorry, Carla, I wish I knew of someone. My husband and I are researching a lot, and you are right, it can take hours and hours! Luckily, I have found that if you google for specific ideas you may end up with quite a few pages to read, but then “save” them in a folder for future reference. My saved documents have titles like: organic pest control or nontoxic household cleaners. I even have a folder for lights, where I have saved pictures of different chandeliers, pendant lights, etc., that I may purchase later for our new home. I do know that some colleges are now expanding their offerings of classes into the world of sustainability. In fact, my youngest son, who graduated a couple of years ago, got a major in Social Science and a minor in Sustainability. If you live near a college or university, you might see if a student could use YOU as their Senior Project, or at least might have a student that would be willing to help you. Good luck. Please let me know how this goes for you!