actual savings from fancy thermostats

I know what the box says, but I've always wondered how much energy fancy thermostats really save. I imagine the number is less than the box says (that's pretty standard as far as boxes go) but I wonder how much less. Has anyone done some experiments and have some numbers to share?

I use them but, before they were available, we just turned down the heat at night and when we were gone during the day.  I doubt they have saved me money since I would have done it manually.

It is nice to get up to a warm house, or come home to one, which means heating a little early, but I figured that's balanced out by the heat going off before I go to bed.

We have a programmable thermostat. It's still very basic in function, there's no color touch screen or wifi connection to the internets, but there are 4 settings per day to set the time and temperature we choose. I don't consider it fancy, but like Timothy mentioned, it's nice to come home to a house that's warming up from a cooler setting after being gone all day, in wintertime.

I don't have any data.  But I do have an anecdote.  I changed out the thermostat at our church from the old mercury circular style to a 7 day programmable one.  I set it to warm up on Sunday morning and a couple nights a week for regularly scheduled events.  55F the rest of the time.  Hit the buttons to warm it up for a meeting or event.  

When I took out the old and put in the new one, I discovered that the old one was reading low by almost 10 degrees.  

So when people would get into the building and set it to 70, it was actually being set to 80.  Eventually it would get a bit warm and someone would turn it down or off (meeting was probably over).  If it was in a house, you'd probably eventually figure out that it was too warm if you had it set at a "normal" temperature but I bet you wouldn't turn it down a full 10 degrees to get to where you think it should be.

That's a great point, Mike.  In your scenario I bet there'd be a substantial savings.

Yeah, for a church or business, I think it makes a lot of sense.  With the old manual thermostat, people were expected to turn it up and then down when they left the building.  I'm guessing it probably didn't get turned down every tenth time.  

I still don't have any data to prove it, but I think it made sense.  For a house, it would be nice to see some numbers from someone to see if it mattered.  I'm thinking the savings of a "fancy vs simple" thermostat would vary based on your eco score.  Or climate.  Or family size.  Or complexity of living/working arrangements.

In that situation, the fact that it reverts to programming can save a lot of energy.  If it's kept low and people turn it up when they're there, it will drop back down at the next set point if someone forgets to drop it back down.

We've never had a programmable thermostat. I honestly think I save more NOT using one, than I would using one. I turn the heat on if we need it, and turn it off when we don't. At our rental, that meant waking up and turning it on, then turning it off (I'd slide it to it's lowest setting, which was 55 degrees F) when I went to work, and turning it on when I came home, and turning it off before I went to bed. It was rare that I forgot to turn it off/down-to-55F. If I'd had a programable thermostate, I probably wouldn't have been in the habit of turning it off when I left, and would ended up having it warmer in the house than it needed to be if I went shopping for a long time, etc.

Now that we have wood heat, the thermostat rarely comes on. I turn it above 55 sometimes to heat the kids rooms at night when it's really cold and the fire has died down. And, sometimes I'll turn it on for a short while on those days when it's not cold enough to light a fire, but not warm enough inside to go without a little heat. That's generally when it's like 50 degrees outside, and 60-65 inside--If I made a fire, it'd be 80+ degrees and way too toasty. So, I turn it on for a short while, and then turn it off after about 30 minutes. I also sometimes turn it on if someone is taking a shower, just to lower the humidity in the bathroom and to make it nice and cozy when they come out.

I've frankly never seen the need for a programmable thermostat. And, honestly, if I come home or wake up to a cold house, I just sit in front of a space heater while the furnace or wood stove heats up more. I'll park my kids in front of the space heater, or just heat the room they're playing in while the rest of the house warms up. I'm pretty sure that's more energy efficient than heating the house for an extra 30 minutes before people come home...

Yes, I'm pretty sure a programmable vs non-programmable thermostat wouldn't change things much for a level 2+ permie.  We "think" about not wasting the heat the house is making.  Now picture your average level 1 suburbanite.  How likely are they to turn the heat down every time the leave the house?  That's where I think the bigger savings would be.

Here's a bad analogy, but I think this is like asking the church choir if they have evidence that singing lessons would help them sing better.  They already sing pretty well so they'd probably say "maybe".  Now if you ask the general public if singing lessons would help them, I think you'd get a different answer.