solar heating-check my thinking please.

[tenax]

so, i've recently installed a replacement 125K natural gas heater. i considered a solar solution but ditched it thinking the rise of roof and # of panels to heat a 12,000 gallon pool would be implausible..now, thanks to another member here i'm thinking..and thinking..and considering the best of both world..supplementing my ngas heating solution with a solar solution. here's my thoughts and questions:

i'm considering buying a 2 panel sungrabber kit-2- 2 ft x 20ft panels. about a 1/5 of the size of my pool.i could go with more but the lift would be pretty high for my pump maybe? in any event, i wouldn't go more than 4-2ft x 20 ft, almost 1/2 my pool size.


we can get high winds so i would buy a high wind mounting kit as well.

i would plumb the solar panel inputs and outputs on the pipe currently running between my filter going to heater. i would put a ball valve on the first side (the input side) of that plumbing so at night when it's cool, i could divert the water directly to the heater as i don't want the water "cooled off" late at night by the panels. i know you can get electronic valve kits but imagine they add quite a bit of expense and i'd likely need to get the "electrician retiring off my projects" in again. this will be low tech with manual valve to supply water to it turned on and off during the day..no biggie for me.

i would use pvc pipe. the pipe run straight up to the highest point of the roof using a 2 panel system would be about 15 ft. if i went 4 panel, add say another 2ft max for 17 ft vertical lift. the vertical runs of the pvc pipe would be about 30 ft (20 ft for the panels then another 10 ft max from the shed to the house roof.

assuming that kind of covers the installation, we get down to my questions.

a) i have a new 1 hp sta-rite max-e-glass pump. all piping except going in and out of my swg for a few inches is 1.5 inch pipe. do you think i will have enough pressure to supply? (15 ft lift? 17 ft lift?) if it helps, the pressure into a clean sand filter is about 20 psi currently.

b) any good guesses on the temp rise i could expect from the panels assuming a sunny day with 20 degrees plus temperature? (i don't think it would make sense to run it on a cooler but sunny day..but i don't know a lot about these things)

c) would you see any worthwhile energy savings on my system using 80 sq ft of panel? how about 160 sq ft of panel? i've been trying to find some chart that shows the temp rise using various sq footage of solar panels but no luck.

again, pool is 12,000 gallons on the outside and i have a solar cover if that helps. i can provide more info if necessary!