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Low cost water heater Answered

I wish to build a simple, afordable, low cost, solar water heater that is easy to construct and does not need electricity. Is that possible?


For most people in developed countries, a modest goal is to offer pre-heated water on the input side of your water heater. That way the water coming into your water heater is either already pre-heated (yeah!) or cold (so the water heater has to fire up). To pre-heat your water, solar power will give you good results on cold and warm days, as long as there is sunlight (electro-magnetic rays). On rainy days, your heater will fire up. It appears to me that ANY VESSEL THAT IS BLACK and SAFE (glass or metal, food-grade plastic) that is BLACK will passively heat your water on MOST days of the year (unless you are in the UK or Seattle). To enhance the impact of the sun, create a greenhouse effect... place a clear glass or plastic container around your black container that will forbid the heated gasses to escape.

Hi, I used to live in Windhoek, Namibia, where I saw black pipes curled up on roofs, just laid on the tiles. These were generating hot water for showers etc apparently. I don't know much about the connections but I'm sure that this could be worked out - how about a team effort from the Instructables community? To get the parts look on your local Freecycle.org for Offered, or join and post a Wanted ad, for the unwanted spare bits that people may have. Then you might be able to build it for nothing! Good luck.

A black water bag works just fine, for moderately small amounts of water. (These are available commercially for use as hot-water showers when camping.) Not maximally efficient, but it meets all your stated criteria...