Using solar to heat pool

Is there a viable way to heat my below ground pool using solar energy? I know I've read about solar water heaters that heat the water in pipes which then send it to a holding tank. Could this be done for a pool? Or could solar panels power a small heater for the pool?

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I've been thinking of either painting the concrete walls and floor of my inground pool a dark color or having dark tiles put in for a different look. I really like the pools where the water looks dark as opposed to the typical blue or white. I was also wondering if the dark walls and bottom of the pool would help heat the water since darker colors absorb the sunlight and heat as opposed to reflecting it with lighter colors?

You'd have to define more when you want to use solar, and how much heating you want. When I've been in Indiana in winter, it was never very sunny.

There are a LOT Of things you *can* do, but solar heating in Indiana would be more of a hobby or experiment, than a efficient and effective choice. But, you CAN do solar WARMING (maybe, 10 degrees) in spring and fall.

As far as dark paint, my experience with that came at the Girl Scout pool at Camp Adahi on Lookout Mountain. I had painted it in white epoxy (it had been dingy plaster, before that) and the girls FROZE in June. The pool was on the mountain, got quite a bit of wind, but had a lot of shade. When I painted it dark navy blue, it raised average temperatures 5 - 7 degrees.

BUT, keep in mind that those seven extra degrees may make your pool feel nasty in August.

As I describe in the thread Water Absorption and Heating from Sunlight, about 60% of sunlight gets absorbed to heat a white plaster pool. For a painted black pool, it would be well over 90% so would have a somewhat higher average temperature. However, an uncovered pool can lose a lot of heat through evaporation (and convection), especially if the air is dry and if there is wind. Use of a clear or light blue (not opaque) bubble-type pool cover can usually increase the pool temperature by around 10-15ºF. Solar heating can increase the temperature more, depending on the area of the solar panels. With a pool cover and solar combined, one can get the pool water to be 20-25ºF warmer than the average day/night air temperature (sometimes higher) during the summer. My pool near San Francisco has a mostly opaque thinner electric safety cover (so not as insulating as a bubble-type cover and not clear) but has solar panels with 94% of the pool surface area (though 2 panels are often in shade so solar is more like 74% of pool surface area). The pool target temperature is around 88ºF since it is used by my wife almost every day for therapy exercise.