Our heating and air conditioning system has officially died. One month ago, it started fading. One minor repair and one month later, it’s in need of attention again. But it’s not really worth it to try to keep going.

The system is as old as the house, which makes it 23 years old. It is not an efficient system in any sense of the word, and my inclination is to search for the most efficient system possible. Unfortunately, the most likely candidate – a geothermal heat pump – comes with extra installation expense.

Many websites (most of which appear to be quoting energystar.gov) tell you that you can re-capture the additional cost of a geothermal unit through savings on your energy bills. Our problem (at least based on my rough estimates) is that we only spend $300-400 per year on heating and cooling.  (Our total energy bill is larger, but that includes cooking, lighting, and so forth.)

Currently, the federal government has a tax credit worth 30% of the cost of a geothermal unit. That’s somewhat helpful, but other efficient units have the same credit up to $5000.  So – suppose a regular heat pump is $5000 and a geothermal unit is $12,000 (and these are totally hypothetical numbers right now). Cost difference = $7000 less 30% = $4900. Perhaps we can shave the cost of heating and cooling by 50%? Then it would take roughly 30 years to break even. That’s supposedly about the lifetime of a geothermal system. We’d like to not have to wait that long.

So – it appears that to make the purchase of a geothermal heat pump worthwhile, either A) I need to have overestimated the cost differential, or B) being green needs to be worth a few thousand dollars to us.


(BTW – we’re getting our first sales call today, and probably another one or two quotes after that. Hopefully, the numbers will become clearer, but I’m guessing that we’ll still have to put a cost on green.)