Solar Hot Water Kettle From Plastic Bottles (and Glass)

Step 6 Performance notes

Fill it with water, leave some air for expansion, put on the lid slightly loose and lean it up against something while facing the sun. The foil side is the side away from the sun. Now wait a while; the time depends on outside air temps and the position of the sun. It can take several hours to get hot in winter weather.

I tried the plastic bottle version, the glass bottle version, and just a plastic bottle painted black. I laid them all out in the afternoon winter sun (outside temps were in the lower 30s Fahrenheit with full blue clear sky) and checked them after a two hours. I don't have a good digital thermometer currently, just a kitchen candy thermometer which is slow and not precise.

The glass and plastic kettles were about the same temperature, although the water from the glass kettle felt slightly warmer than from the plastic one. They measured about 95 degrees F if the candy thermometer worked right.

The black plastic bottle was just cold, just barely warmer than outside air temps.

Comments

[bruzzbuzz]

http://www.you-can-go-green.com/ The simple and easy to make DIY projects that also promote environmentalism are the ones I like best. I have a blog called You Can Go Green and I like to post the really great projects I find. I am hoping you will let me post a link to this one.

[robbtoberfest]

Oh, I don't mind. Thanks for asking though.

[SpacedCowboy]

Great instructable. I would like to try this one with some mirrors in brisbane. I have seen camping showers based upon the simple black bottle, which aren't very effective. I wonder if this greenhouse effect could be applied in a similar way? This might also have applications for energy production on the cheap (stirling engine style?) but I'm sure you've thought of a lot of that already. Looking forward to future entries!

[isacco]

Very good Instructable! I like the simple ways of using solar energy for everyday needs. Congratulations!