Over a long period of time, they can be cost effective. Even if you have to
change out the equipment after 15 years, you can still use the existing
ground loop. In any case, the OP simply asked for a state of the art heating
system in exclusive (multi-million $) housing area. He didn't ask about
price or cost effectiveness.
If done right, the air temps coming out a geothermal are much warmer than an
air-to-air heat pump and he'd have built-in air conditioning. If he were to
build that type of house with no duct work, you'd have a hard time
re-selling, especially if they get "some pretty warm days in the summer".

"Edwin Pawlowski" wrote in message
t...

"Bob" wrote in message
...
Geothermal heat pump.


Have they gotten more cost effective? After geothermal, a good solar
system
but that depends on how much sun you get too. In any case, the system
should
have backup if power lines are down or it would not be so state of the
art.

In addition to a good heating system, I'd want state of the art
construction
for maximum thermal efficiency using something like ICFs (insulating
concrete forms) www.polysteel.com or www.integraspec.com