Since the air conditioner is the largest energy user in your home, limiting its use will reduce your bills the most. But it's just one of the areas where you can save this summer!
Set the thermostat at 78° or higher. You could reduce your air conditioning costs by 8% just by raising your thermostat by 1 degree in the summer.
For more energy savings, set the fan switch on your air conditioning system to "automatic", instead of leaving it always "on". This also applies to room air conditioners.
Be sure to check your air conditioning filter at least once a month, and clean or replace it if you find that it's dirty. This can also give you some relief if you're experiencing allergy symptoms.
Check the accuracy of your thermostat by placing a thermometer next to it. You may be over-cooling your home. For example, the thermostat may indicate 78° when the room is really 72°, increasing your cooling cost by 30% or more.
Ceiling fans spread cold air more evenly throughout the room. The fan direction should be DOWN for summer and UP for winter.
If you have a fireplace, keep the damper tightly closed when not in use. You might also consider a glass fire screen, which can help minimize the loss of conditioned air.
Make sure the weather-stripping around your doors and windows is in good condition. Keep doors and windows closed when the air conditioning is on.
Close blinds, draperies, or shutters on sunny days to help keep the heat out. This is especially important on any windows or glass doors receiving direct sunlight.