I have been dabbling with solar energy since the Carter administration. There were a couple of IBM engineers who went crazy with it. One had an active solar heated house.
It was a maintenance nightmare and he ripped it all out to sell the house. I had a solar heated spa that my ex made me rip out on my way out of town.
I now have a solar heated pool now. That works and actually does make sense. I looked into solar power for the pool pump I hit the wall. If nothing ever broke, my payback would be 20 years or so. That is about as simple a PV setup you can think of, no utility connection, no transfer equipment and minimal storage. When the collectors provide enough power you run the pump. It will be over $10,000. (1.5 KW system)
One of the problems with that "1.5kw" is that is on a cloudless day at noon on the summer solstice (or which day you have it perfectly aimed for). Any other time it will be putting out less.
The basic rule in solar, or most alternate energy, is, the simpler the better. Solar pool heaters are decidedly low tech, they use the existing plumbing and pump and they will buy you some extra swimming days, plenty if you cover the pool. As soon as you start getting much more complicated the payback periods and the PIA value starts increasing exponentially. If this is just a hobby, try to buy other people's heartaches, cheap and play but do not expect to really save any money.
I got my pool collectors from one of those "roof leak" people.