If there's *something* being discharged (even if it's just hot water)....
Actually, I'm not sure if you are referring to geothermal heating but, in this type of system, the ground water is actually cooled and it is the resulting byproduct heat from this cooling process that is used to heat your home. Kind of like the major heat that comes off of the back of your refrigerator. Well, at least the older, very inefficient ones.
An interesting process that I also misinterpreted until researching it for a new home.
