A Homemade Solar Water Heater

Inspired by the work of other MOTHER EARTH NEWS readers, the author came up with his own design for an affordable homemade solar water heater.

| November/December 1980

066 homemade solar water heater

The completed homemade solar water heater. You can do more with less when it comes to alternative energy.


I've long been impressed by the simplicity of many of the homemade solar water heaters developed by MOTHER EARTH NEWS' researchers. And now I want to tell their energy-conscious readers about a solar "breadbox" device that I've come up with.

My unit's absorber/storage tank was salvaged from a discarded water heater. I welded legs onto the cylinder and installed an inlet fitting to send the cold water to the bottom of the tank. Then I painted my creation with "hi-temp" flat black paint.

The tank sits in a plywood box, the inside of which is generously insulated with fiberglass. Acrylic plastic (with a couple of galvanized wires for support) is used for the window, and all interior box surfaces facing the water tank are lined with polished sheet aluminum.

My creation's only moving part is an insulated door/reflector that I open every morning and close at night (it's angled just right for catching the low-slung winter sun, making the box even more efficient in January than it is in July).

The exterior surfaces are covered with durable sheet aluminum. The pipe that carries the solar-heated water — as well as any cold water pipes exposed to the outdoors — is also well insulated.

Since installing this simple solar device (which supplies preheated water to our conventional hot water tank), we've had more hot water and a lower power bill. The out-of-pocket costs for my entire project totaled $65. I've been so pleased with the heater that I'm building another one: a modified version of the original unit, which promises to snag even more free BTU than does my first design!

6/3/2015 9:44:42 AM

I feel great reading all these DIY projects because it means poeple care about our environment! Thank you for sharing it with us! We've got to make the society conscious, and now we have all we need (recently even I started using an app http://easysolar.co/ on my phone to monitor my PV system, it's that simple...), we just have to take use our imagination :) Best of luck with all your future projects! And don't forget to post them here :) Daniel

1/11/2014 10:56:25 AM

waiting for the crash good luck everyone (we must stick together to survive

10/26/2013 5:44:53 AM

It's really an interesting article. Thanks for sharing. http://www.agnisolaar.com/solar-water-etc.html

jacques st georges
1/22/2012 4:06:30 PM

Hi , i am really interested in the solar water heater designs with the collectors, tank and radiant floor heat however I am curious to know if this system would work with gravity fed water supply. I am totally off grid and rely on water from a 1000 litter tank elevated 15 feet . PS I am a new subscriber to mother earth and I believe I just found my new favourite subscription. Thanks

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