If you have a heated pool, you understand how expensive it can be to heat a pool. Because of that, many people resort to solar covers, solar panels to heat water, etc. There are other ways to heat a pool that are economical (free) and environmentally friendly.
If you are like me, you hate waste. It isn’t about the money spent on certain things, it is about the waste. Efficiency feels good. Green or not, efficiency feels good and happens to be “Green” most of the time.
When certain items operate they waste a lot of energy. A big one is your air conditioning unit. Another is a pool heater. You can actually take the heat that is wasted by your A/C unit and use that energy to heat your pool. Your A/C unit is pulling the heat out of your home and moving that heat outside. It does this with a coolant and coils. The coolant that leaves your home and runs through you outdoor A/C unit can be intercepted to heat up your pool water. It is that simple. You simply need to redirect that “hot” coolant and run your pool water past it (past a coil that is much like a water heater).
The item that you are adding to the loop between your A/C and your pool filter is called a “Heat Exchanger” and has been around for years. Frankly, this is one those items that should be used much more than it is.
Take a look at the video from This Old house and they explain the whole process along with the installation steps. Fast forward the video to the 14 minute mark for the segment from Richard Trethewey.