I have a terraced lot with approx a 20' drop from one level to the next.  Planning on a walkout basement which would be bermed into the hill on 3 sides and probably partially the next floor as well to scale the hill height.

Is there an opportunity to utilize the excavation for the lower level for to install the geothermal runs possibly around the foundation during the excavation?  Is this something that might be cost effective?

I'm planning a passive solar, energy efficient home and have read that geo could be tough to get a good bang for the buck ordinarily, but perhaps be more feasible w/ the take advantage by piggybacking on the "free" excavation for the basement/foundation?

Thanks.

It is recommended to stay at least 5' from the foundation

Didn't hear that it was tough to get "bang for your buck" here.
What do you suppose will pay you back more quickly for your investment.
Certainly not fossil.
Joe

This same question was asked on another web site forum.

http://www.geoexchange.org/forums/viewtopic.php?f=2&t=113

Basically the big hole in the ground is going to be the least expensive thing to pay for when installing a new geothermal system.