I just purchased a house with electric baseboard heat and I want to install set back thermostats. I did some research and found a unit that does not use a clock. The unit uses the light level in the room to decide when to move to the higher setting. On the surface this seems like a good idea since you wont be heating a room that is theoretically not in use to the "comfort level." My concern is that the room would all ways be cold before you turn on the lights as opposed to a clock based system that ramps up the heat when you plan to be using the rooms. The clock based units are proven technology but I can see where the light based units could save more money in the long run. (Unless the lights are left on)
Anyone have any experience with these light based units? Are they a better choice than the clock based units? I have also thought about using a combination of the two. Putting the light based units in the upstairs bedrooms and the clock based units in the main rooms downstairs. Does this sound like a viable plan? I think it would provide the comfort we need in the main part of the house (the larger rooms) and help keep costs down in the other rooms.