We routinely get temps over 100 in the summer (with high humidity, which reduces the efficiency of the cooling units) and below freezing in the winter, with occasional bouts of temps below 10 degrees. We had 11 degrees or lower for over a week this last winter.
Also, a condo has firewalls (high R-value) and is insulated by other units on two sides unless you have an end unit. This house has all the living space on one floor, which means more s.f. in contact with the outside world. And in August in Atlanta, that's HOT!
I would happily trade my current August electric bill in a conventional 2-story house for my August bill for all utilities in the solar house.
$100 is a guess, by the way, and I didn't want to exaggerate so I guessed a bit high. I do NOT keep 15 year old utility bills for a house I no longer own!
Yeah, I just bought a home in central Kentucky. I know what you mean about the temps. But even then, just using the heat pump on our little 1100 sq ft place, the bills were around $100 in that stinking humid 95+ stuff.
And yeah, the condo stuff you mentioned is exactly why we chose it. Our house had heat bills in the winter that reached a peak of over $400.