Setting air conditioning to 78 degrees Fahrenheit during warmer months provides adequate cooling while saving on energy bills. For the greatest energy efficiency, allow the temperature to rise while the house is unoccupied and while its occupants are asleep.
Lowering air conditioning temperature settings doesn't cool a building faster, and reducing the temperature to 72 degrees Fahrenheit increases cooling costs by 12 to 47 percent. Use a programmable thermostat to automate temperature adjustments and cool the home before family members return in the evening or wake up in the morning. Although one a homeowner can manually override this type of thermostat, forgetting to adjust the air temperature to its ideal level usually causes inefficient energy consumption.