swimming pool heating systems
Darin W asked:

Is it possible to use an air conditioner to heat a pool? It seems like I might be able to use a liquid heat exchanger to cool the hot part of the air conditioning cycle using swimming pool water. Can someone give me an overview of how to build a system like the following myself (or at low cost by requesting the right work to be done by a professional)?

http://www.toad.net/~jsmeenen/pool/
http://www.freepatentsonline.com/3976123.html

Thanks in advance! This could be very cool! But I’m also wondering why it seems there are not a lot of people aready doing this — leads me to believe that it might not be worthwhile. Perhaps the air conditioner does not put off enough heat to be useful?

Note: I have also been looking at heat pump systems, which I might end up with, but it would sure be nice if it were possible to modify the existing system instead at a reasonable cost.
To the poster who asks if there is a correlation between air conditioner use and need for pool heat, in my case, yes there is for several months of the year. Even in the hottest months, this could potentially be used to focus all the heat towards the spa, or for household hot water.

Another poster asks if it’s feasible, and there seem to be patents and some devices that do this for either pools or household hot water. Also, stand alone heat pumps are sold for this purpose and they are very similar to what I am proposing here. Air conditioners extract heat from indoors and dissipate it to the air — wasting it. Heat pumps are sold to extract heat from the air to heat the pool — wasting the cold that they generate by dissipating it into the air. Is it possible to have the best of all worlds — nothing wasted + use the existing AC equip through modification?