“DIY Solar Water Heater. A Homemade “flat panel” COPPER COIL Solar Water Heater. Easy DIY. Full Instructions. Super hot temps (sustained at 165F+). Fast hot water. No electricity needed. Easily hooks up to standard water tap/garden hose. Reaches temps well over 150F (water pasteurization temp) so it works to clear/kill any pathogens (if a non-municipal source is used). It’s super portable so it’s good for camping/off-grid/emergency as well as everyday use.
Couple of notes: water flow rate verified with a measuring cup and a stopwatch. (Roughly 1 oz. of hot water every 1 to 1.5 seconds and scaled up – one gallon every 2-3 minutes or 20-30 gallons per hour). About the copper tubing: a 50 foot roll of tubing is much cheaper than smaller rolls connected. *Only $24.95 for 50 ft (but $17 for a 20 ft roll and $10 for a 10 ft roll). The glass is just standard window glass and the paint is flat black. It’s thin flat design allows it to be easily stored in a closet, under the bed etc… *”Seal it” according to your climate conditions and whether you plan to leave it outside.”
YouTube
Good, compact, easy to build solar water heater. Check the Comments section below the video for more details and suggestions.
No freeze protection, which is the real challenge for solar thermal. In climates where that isn’t needed, such systems become much more feasible and cost-effective, and a variety of even simpler systems proliferate, like the good old-fashioned black-painted metal barrel.
We used to have a black painted barrel on the roof in Colorado but the water almost never got nice and warm. Now in the tropics it’s the opposite situation where it’s easy to heat water with the sun. In fact, it’s easy to overheat the water and get scalded with the wrong design.