I am building a new house, and I am considering getting one of these systems to be located on my shop.
http://www.siliconsolar.com/80-gallon-thermosyphon-solar-hot-water-system-p-16559.htmlI have oriented the house to face the street, but the shop is turned 30 degrees so that one one side is due south (for solar panels DHW now, maybe PV later).
The length of pipe running from the shop to the other end of the house makes me think that I need a hot water heater at that end of the house, or one more centrally located.
What I am considering right now is a system that incorporates one of these Thermosyphon systems (with some non-toxic antifreeze). I am thinking of having one or two small electric hot water tanks (one at each end of the house). Then, have the cold line for the water heaters come from the Thermosyphon. I am thinking of going with tank heaters, since from what I have read, the on-demand electric ones may not be that much more efficient.
If I wanted to get fancier, I may replace the drain plugs with a pipe fitting; then, add a pump that circulates hot water from the Thermosyphon to the water tanks. That way, the electric elements would not be used much at all. I would control the pump with a solar water heater controller.
Of course, this system would assume that the solar collector could heat the Thermosyphon thermal mass tank and the two water heater tanks.
I live in central Texas, so I get a lot of sun.
What do you guys think?
Cost is a prime consideration.
Thanks