JHAP:
I'm really interested in the Geo thread as well, as I'd like to go that route to get away as much as possible from the Utility companies. With Mark being in Indiana, that doesn't bode well for me. A neighbor had a heat pump installed and it took them almost 6 months to get it running properly. I'm not sure if the installers are trained properly in Geo system sizing, installation and operation, much less troubleshooting!
I figure that the more that I learn about Geo, the more intelligent questions I can ask about the system when it comes time to ask for quotes.