PV Gap

Valerie Said:

how to build a water heater using solar energy?

We Answered:

I built one years ago when I lived in Arizona. I took a 4X8 sheet of treated plywood, put 2X6 treated sides on all four corners with Liquid nail and screws. Then I took one inch. black plastic PVC pipe and up and down in rows with 90 degree elbows about every six inches between the rows. I put the plastic on stand offs with short pieces of 2X4's. Then I filled the entire thing with Lava Rock, and put a clear plastic cover on it. I had it so with a frame under one side and two old sizer jacks so I could raise and lower the high side to adjust for the angle of the son. We was on a well and the well pump would push the water through the system and into a propane water heater. I only used about half the propane after I set this up. I don't think it would work well where I live now. I don't get enough morning sun. Lay mirrors on the ground in front of this set up and you will increase the heat.

Donald Said:

how useful is a solar water heater in Bangalore ..does it save any energy in blore ?

We Answered:

I have one at home, works well most important is the placement of the heatcells or the solar panel......try it and i am from bangalore

Jeff Said:

Solar Water Heater?

We Answered:

20% of 700W/m^2 = 140W/m^2

You need:

Q = 200,000grams (4.184J/g.C)(20C) =16,736,000 Joules

So:

(16,736,000Joules)(1W-sec/1J) / (140W/m^2)(3600seconds)

= 33.2 m^2