I hate to reply to a reply, but if you'd like an example of saving 10% energy in a really cold area where bills are really high, lets take my sister, a 40hr a week worker where it got down to -30 during the recent cold snap. Now 70 - -30 = 100 degree delta T. Now the simple way to save 10% would be to permanently set the thermostat to 60F. But thats a bit chilly.
So she works 40 hrs a week which works out to 25% of the time. So we can just turn the thermostat down 4 times as far for a quarter the time. So... She leaves for work and the thermostat drops to 70-40=30. Which is unfortunately below freezing so all her plumbing pipes burst. But at least she saved 10% on her heating. Also she owns an indoor cat and at 30F she'd turn into a frozen cat-sicle.
So she pays $300 for a thermostat that can't save her 10% on her bill unless she destroys all her plumbing flooding her house and killing her cat. I'm not seeing this as a great selling point.
So, no, cold parts of the country are precisely the locations where you can't achieve great heating savings because its mathematically impossible because its so cold outside. Maybe a 20000 sq foot mcmansion on the coast in florida, it might work there. But not where its cold.
Just to say it again, extreme cold is where a thermostat is of little help.
But imagine that there are 4 or 5 months a year where the outdoor temperature is 15 or 20 degrees colder than a comfortable indoor temperature. And imagine turning down the thermostat during the night in those periods, not just during unoccupied times.
(I realize that more energy is used during cold periods, but some huge portion of the country lives in areas that rarely see 20 for the several months they are below 60).
So she works 40 hrs a week which works out to 25% of the time. So we can just turn the thermostat down 4 times as far for a quarter the time. So... She leaves for work and the thermostat drops to 70-40=30. Which is unfortunately below freezing so all her plumbing pipes burst. But at least she saved 10% on her heating. Also she owns an indoor cat and at 30F she'd turn into a frozen cat-sicle.
So she pays $300 for a thermostat that can't save her 10% on her bill unless she destroys all her plumbing flooding her house and killing her cat. I'm not seeing this as a great selling point.
So, no, cold parts of the country are precisely the locations where you can't achieve great heating savings because its mathematically impossible because its so cold outside. Maybe a 20000 sq foot mcmansion on the coast in florida, it might work there. But not where its cold.