wv1720
Member
What you want to research is a closed-loop drain back system.
You could think about a batch system like these:
Solar Water Heating Projects and Plans
Gary (from BuildItSolar)
Ok folks I am new to the solar world so be easy on me. I was thinking about adding a solar Pre- water heater system to my 40 gallon electric hot water heater. I was thinking this may save me a little money each month on my electric bill. I was also thinking this would be something I could build myself. I am think I can build a square box 10'X10'X8" out of treated wood painted black and mount it outside my roof above my hot water heater. Than insulated inside the box with foam board inside. Than run copper pipe or cpvc pipe back and forth inside the box to absorb the sun's heat. Than cover the box with a piece of glass. My thoughts are that if my ground water average temp of 72 degrees going into the Hot water pre-heater it may come out of the pre-heater at about 92 degrees plus ( just a guess) That would raise the temp of the water going into my 40 gallon electric hot water by 20 plus degrees there for not working my hot water heater as hard to get to the 120 degree setting it's on. Do any of you have a system like this? What kind of return could I expect on my investment. Like I said, I am new to the solar world so any information or guidance you can give me would be appreciated
I am a Californian, and we get lots of sunshine nearly year around. I fell for the tax incentive in 1982 for going solar. We built a large home, and thought the tax savings, plus the free heated water for the master bath spa, and hot water system would be worth it. The system cost us $25,000 in '82. The fourteen 4'x 8' panels are located on the back side of the home facing South, which was an incentive for the system being out of sight of the front of the home.
Well, the second winter a freeze plug on one of the roof panels failed that cost us $1000 to replace one panel, because there was no insurance on the system, and the company that installed it no longer existed!
Within the next few years, apparently a frustrated golfer that must live on one of the surrounding ridges started sending golf balls off his backporch or yard, in our direction into our rural valley taking out another solar panel.
We also have two large storage tanks, one each end of the home. A special stainless steel one, that was placed in a confined area that cost $3000 to make, plus the standard hot water tanks giving us about 500 gallons of hot water, with instant hot-water too, via of special electric pumps on timers! When one of the large 250 gallon tanks was installed; there was no water-proof plate under it, and is now leaking causing "dry-rot," that has to be addressed. We still use the system, but will never recover our investment!
I would look at your project as a challenge, with the reward coming from the "learning curve?" There is no free lunch, but technology has improved however.