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Solarbox 1453 Resized1
Daniel made a fantastic soda-can water heater, he writes -

While I have electricity out to the garage now, heat has been an issue all winter long. Mattar graciously lent me his kerosene heater, which did an okay job of taking the bite off the chill. Insulating the garage would go a long way to help keep the bitter Vermont cold out, but that’s a project for another day. I decided instead to take advantage of the south-facing side of the garage and build a solar furnace to collect some of that sunshine just bouncing straight off my garage. My dad built one years ago and said he recorded a 110-degree temperature differential between inlet and outlet. And I had enough scrap materials around the basement to do something similar to what my dad built.

Hemmings Auto Blogs » Blog Archive » almost free garage heat – just drink a lot of soda, Thanks Jeremy! Link.

Phillip Torrone

Editor at large – Make magazine. Creative director – Adafruit Industries, contributing editor – Popular Science. Previously: Founded – Hack-a-Day, how-to editor – Engadget, Director of product development – Fallon Worldwide, Technology Director – Braincraft.



  1. Dax420 says:

    That is not a water heater. It’s an air heater…

  2. ZapWiz says:

    Find me the almost free Garage A/C, I’m in Texas

  3. Moofie says:

    Not to go all thermodynamics on you, but the temperature differential across the can array isn’t going to tell you much about how much heat you’re going to be able to put into the room. With such small thermal mass, even if you used a fan to force airflow through the system, I would guess that you wouldn’t be able to tell the difference between ambient air and air that went through this device.

    Not unless it were a LOT bigger. And a lot heavier.

    Hate to rain on the ol’ parade, but I’d guess there are more effective solutions to this problem. Like, you know, fire.

  4. amp2003 says:

    Also worth mentioning. I think I saw this on Make as well.

  5. Sally599 says:

    I think its great :)

  6. BeardedOne says:

    Check out the link above and I think you will see that this can work! It doesn’t need mass..
    Mass is for storage of heat not for heating air.. you can solve the mass problem with bottles or barrels of water in the rafters that will absorb the heat after it enters the building and will then radiate it back out when the heater is no longer heating..when the sun stops hitting it..
    INSULATION will make a HUGE difference in keeping up with heating a space however..but to just take the chill off..this will work just fine..and do a surprising job even on days that are less than perfectly sunny! More size will produce more heat but you may not need or want that!
    I would suggest visting the site listed above and the sites linked to that link as well.. good information and lots of info..another good source is
    the LittleHouses group on Yahoo..

    1. molly starlight says:

      Loved it!!! Could see me building one a if I get a garage. I was thinking ice fishing shack.

  7. Anonymous says:

    what about using 200 ft copper fluid filed tubing and plumbing it into a small fan forced radiator into the house mine gets up to 112* or try using a different metal cause aluminum reflects radiant heat at 95% not absorbs for efficient heat exchane

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