I find myself thinking of ways to reduce the electric bill besides sweating and shivering. Having seen just glimpses of geo thermal and having just enough knowledge of A/C to be dangerous. Im looking for you guys to step forward and enlighten myself and others. I live in the south along the coast where the ground water is relatively close to the surface, I have a canal in my back yard. That being said I believe Im a great candidate for this type of system. I have seen 2 styles of coils one that uses vertical the other uses horizontal coils, The other a twin well that pumps water up one well and then back down another. With a canal behind my house what about pumping that water? The temperature runs from the mid 80s in the summer to one time we had a skin of ice on it. It is salty so Stainless would be required to come in contact with the water, what about sediment in the water. Do you think its possible to build a system?