Just saw this post and was amazed by the prices I saw for the Geothermal systems :confused2:. I built a new house 5 years ago and put in a Geo system and my total cost for the unit (3-1/2 ton), closed ground loop (2100 feet) and ducting was 15k total. Quite a bit less that the 25-30k mentioned here, and in my rural area we don't have gas so the system has already paid for itself compared to LP. We have a 2000 foot ranch with a full walkout basement (Another 2000 feet) and our highest bill for that meter has been about $140 the middle of winter. As stated by someone earlier, if it is a new install it's hard to beat the payback where I am at.