Changing Your Thermostat Setting Comfortably Cuts Your Electric Bill
Do programmable thermostats
save you money? Some believe that setting the thermostat higher while you're
away wastes electricity by running the A/C harder to cool the house for your
return. This article explains which is true and why, and shows how much
electricity a programmable thermostat can save you with little discomfort.
Heat flows from hot areas to cold at a rate governed by two things. Better
thermal insulation between the areas slows heat flow, while greater temperature
difference increases heat flow.
A higher thermostat setting while you're away raises interior temperature,
decreasing the difference between indoors and out and reducing heat flow into
your house. Just before you return, the programmable thermostat lowers the
setting and your house cools down. Since less heat flowed in, the A/C requires
less electricity than it would have with a lower thermostat setting.
