As seasons come and go, you keep your home within a fairly consistent internal temperature range (65˚ to 75˚ F). That means, during peak conditions, your heating and cooling systems have to work harder due to the temperature gap between the exterior and interior of your home–and it shows up on your bill.
Summer vs. Winter. Who’s the Bigger Culprit? It’s All About the Temperature Gap.
Look at it this way. You have your home’s thermostat set at 70˚. In summer, when the exterior temperature reaches 100˚ F, you have a 30˚ gap between inside and outside temperatures. This gap becomes smaller at night when temperatures come back down, so your AC unit doesn’t have to work as hard to overcome the difference. Winter is a different story. The same thermostat setting of 70˚ F may have a daytime gap of about 20˚ if the outside temperature is in the 50s. But when the sun sets, temperatures drop and the gap increases. And if temperatures dip into the 20s, your heating system is working against a 50˚ difference. That temperature gap would be equivalent to a 120˚ F summer day. Plus the nights are longer, so you are inside using more interior lighting. And the energy usage list keeps growing. Even in Texas, it takes a lot of energy to overcome those winter nights.