During the summer, programmable thermostats can help save energy -- and reduce utility bills -- by raising your home's temperature at predetermined times, such as when you're at work.
In the winter, they conserve power by lowering the temperature of your home at select times, such as while you're sleeping.
"It doesn't take more energy to reheat the house than you save during periods of set-back, despite the myth to the contrary," says Bruce Harley, technical director of Conservation Services Group of Westborough, Mass., and author of "Cut Your Energy Bills Now" and "Insulate and Weatherize."
Remember, the programmable feature won't save you a dime unless you actually use it.
"Programmable thermostats by themselves don't actually save money -- unless you use them," he says. "Most models out there today come pre-programmed, which makes it a lot easier for them to do their job."
SAVINGS: A programmable thermostat can trim between 1 percent and 5 percent off your heating and/or cooling energy costs, Harley says.