We're building our "forever" 2700sf home in upstate NY, and are trying to make final decisions on how to heat and cool it. It got down to -11º this winter, and hot & steamy summers are no longer uncommon. Comfort is a big deal, but we will probably occupy the house only 2 or 3 nights/week--we both travel for work.

We have priced various methods of heating & cooling. The differences in prices--from the same contractor who has shared his open books with us--is staggering. We are trying to make an educated and informed decision.

Oh yes, one more impt detail: our recently completed well is a flowing artesian: in January, producing 27gpm of 54º water! That has inspired us to try to make geothermal heating & cooling work, since it can be plumbed (legally) as an open system.

SYSTEM (A) "cost x" High Efficiency LP furnace (96%) with 13 SEER air. All-air distribution system.
SYSTEM (B) "cost 1.6x" Geothermal Heat & Cool, but with fewer units & zones than conventional high efficiency. All-air distribution system.
SYSTEM (C) "cost 1.6x" LP High Efficiency boiler (95%) for multi-zone underfloor radiant & two-stage cooling using well-water as first stage with hydro-air coils. Radiant-floor heat and air for cooling & ventilation only.
SYSTEM (D) "cost 2x" Similar Geothermal Heat & Cool with an additional water geo-thermal unit. All-air distribution system.

Price differences are significant--between $10,000 and $20,000 over the "base price" System A. And that's what is making me nuts--trying to justify the premium for Systems B or D for what are essentially apples:apples air systems.

The geo equipment mfr is trying to sell me on a projected payback over 10 years. That makes little sense to me, too. I don't believe anyone can predict costs of equipment or fuel that far out. Even if they could (let's assume that both will cost more), it seems as if there would be no payback--it would be a wash. I'm not even bringing into the equation that this is *not* a 24/7 live-in home for 4 occupants with great everyday energy demands.

One person suggested we put the savings into the best (most efficient) insulation and other building components, which I guess means open or closed-cell foam.

Meanwhile, our well is putting out by itself 38,000 gallons of water every day. Seems a shame not to be able to take advantage of it and reduce our carbon footprint responsibly.

So what's your take? Is there something faulty in my thinking? Am I missing a different geo source mfr? Is this just the wrong time to invest in new technology?

Thank you for any and all feedback. --Mark