According to :
I'd do a lot of research before I converted to a heat pump, air based,
system in Michigan. I seriously doubt it's a sound idea in that
climate, but a heat pump/geo thermal system may be an alternative.

A air source heat pump will work reasonably well in Michigan climates,
but _not_ with electric backup. Gas backup would work much better.
--
Chris Lewis, Una confibula non set est
It's not just anyone who gets a Starship Cruiser class named after them.