Use Your Thermostat to Save Big on Your Electric Bill This Summer

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.

What Happens to Electricity Usage with a Programmable Thermostat?

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.

This article will concentrate on the latter factor - temperature difference. 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.

BGE Conducts Pilot Program to Reduce Critical Electricity Usage

BGE is the electric and gas utility serving much of central Maryland. In summer 2008 BGE started a pilot program to reduce electricity usage during critical times, giving program participants a $150 for participating. Two methods were tried - call them the "carrot" and the "stick."

The stick method reduces electric rate nearly in half during off-peak hours (85% of the time). Peak electric rates (13% of the time) are left unchanged. Critical period rates (2% of the time, 2 to 7 PM of 12 especially hot days) are punitive, at nearly 12 times higher than normal. BGE notifies participants the day before each critical period.

The carrot method uses a uniform rate, providing instead a credit of $1.75 for each kilowatt hour (kWh) saved during critical times. The electricity saved is calculated by comparing to average electricity usage during the previous 3 afternoons.

Personal Experience with the BGE Pilot Program