Hello, I am in the solar biz and a lot of companies like the one I work for also sell solar pool heaters. For my company, pool panels are really a tiny side-line to the main biz but I have some knowledge of this.

As a new pool owner, I want to know if solar is really the best option for free pool heating. I would never consider a paid energy pool heater. But, from researching I see that there are actually a couple other free heating options besides solar.

1. SolarAttic Pool Heater - heats a pool using heat from an attic.
2. Hotspot Pool Heater- heats a pool with heat recycled from an air conditioner

I think I pretty much know the advantages of solar as compared to heat pumps, gas etc. I am hoping somebody could tell me opinions about these other two options. And also, are there other free heating options beside solar and the two I mentioned?

J Baker