[seanwoods]

Not all geothermal systems are closed loop. I have an open-loop geothermal system at my house on Cape Cod, MA. It uses the same water pump I use for my domestic water, runs it through the heat pump, and discharges back to the aquifer via another well drilled exclusively for this purpose.

[sigmaprimus]

Interesting, do you also take advantage of the excess amount of water being pumped through your system with a reverse osmosis system?

I would imagine this would be of great benefit if You are already moving the water to heat and cool your home.