homebrew solar hw panel pics

[mikey ny]

   I finnaly got time to post some pics of my homebrew solar panel. I built a wood box to fit the size glass I had. 4 ft by 4 ft 8 inches. I put 7 layers of scrap styrofoam in the bottom and sides of the box and lined it with some scrap aluminum. Next I put in 3 layers of .060 epdm rubber left over from a roofing job. I built a manifold of 1 inch pipe and used 1/2 pipe for risers. A total of 16 risers app 4 ft 5 inch's each.Next I covered the pipe's with 3 more layers of rubber. I used the roofing adhesive to glue the rubber to the pipes hoping to get good thermal transfer. I used some left over black onx rubber tubing to get to the solar preheat tank. A salvaged grunfos 3 speed pump is controlled by a snap disc in the panel set at 120 minus 20. The cold water goes into the preheat tank first and then into the gas water heater. I will drain it down in the winter and use the wood boiler for hot water. We have a large family so our gas bill was 80 therms or more per month. We now have it down to 21 therms give or take a few. It saves about 60 bucks a month. I have close to $150.00 in pipe and fittings. Next year I will build one more and join them together.





This is the wood box lined with styrofoam and alluminum





This is the glass from my neighbors old picture window.

This is the front view.









notice  the oven temp sensor on a hot day it reads about 150 to 200 f.





see the snap disc in the upper right hand corner.

[willib]

very cool er hot! , and a nice savings too!

its interesting that even at the angle of the glass in the second photo ,

the windows in the house behind the photographer are parallel to your porch

[powerbuoy]

The panels temperature is 150F, ...how hot is the water when it leaves the panel, or what is the temp difference between water IN and OUT?

Powerbuoy

[CmeBREW]

Really nice Water pre-heater. I am planning to make one very similar to yours, except i was thinking of using cheap ABS (black) plastic pipe since copper is SO expensive. I just hate the idea of 9000 watts (grid)heating up 45 degree water from the underground each time we each take a shower. My plan is to use a small water pump to recirculate the cool/warm water from the hot water tank back out to the panel outside, controlled w/ thermostate like yours. The sun is always shining where i live. Looks like your getting great savings already.  -Good work!

[mikey ny]

  The temp sensors I have on the in and out are used from an old boiler and, unfortunatly are very inaccurate. I know the cold water coming in is around 55 to 60 degrees f. The slower the pump runs the hotter the water comes back. On a hot day if I turn off the pump for 10 minutes the water comes back so hot you can barely touch the pipe.  I believe I am getting about 10 degrees hotter out the other side. By the end of the day ( a hot one) I have 40 gal of water that is about 100 degree's. So we went from 60 to app 100 degrees through the cource of the day. The tank happens to be on the other end of the house app. 40 ft of pipe so I have some pretty good losses due to convection and the pipe is not insulated yet. I am sure there is room for improvment in other areas also. I tried running the pump full time all day and shut it off manually but the snap disc seems to work better. It simply runs itself so I don't have to do anything at all now.

[Frank06]

Have you considered building a small batch preheat tank?  Find an old water heater and remove all the insulation.  Paint it flat black and lay it on its side in an insulated box with glass or plastic glazing.  Water in the tank will heat up on its way to your regular heater.  If you live in a freezing climate it's easy to plumb-in a bypass.  

[powerbuoy]

From the size of your panel I assumed that you have to recirculate all day to get a good rise out of it. It looked like there is enough space to add more copper?

Powerbuoy

[Breaking Wind]

Mike,

I think should work well.....as long as your neighbor doesn't find out that you took his picture window out.