Gas furnaces have electric-powered blowers to move the hot air through the ductwork. To help maintain the desired temperature in your home, the furnace is running for longer periods of time. Electric humidifiers used during extremely cold weather could also add to increased energy consumption. Be sure to replace heating and cooling system filters once a month. Dirty filters restrict airflow and increase energy use. Keeping the unit clean and properly adjusted will reduce energy use and save up to 5% on heating and cooling costs. Keep forgetting to do that? Tip: get in the habit of replacing your filter when you receive your monthly electric bill.