Geothermal Heat Pumps

  Q: Have you done any calculations (what % higher than air source) to show when geothermal is a better option from a financial sense?

A: I have not done precise modeling, but if you can generate electricity from solar panels at 5c/kWh (doable with a sloped south-facing roof), and you can get the wells drilled a lot cheaper than my quote, and you get the federal tax credit then I think geothermal starts to make financial sense.