Here are a few ways to lower your home's temperature and your energy bills:
Real air not air conditioning. As much as possible, use natural ventilation. The trick: keep your house closed during the day, and open up the windows (while ensuring they are secured) at night.
Shut out the light. Keep draperies and blinds closed tightly during the day, and keep the sunshine (read heat) outside.
Turn down the heat. One of the best ways to keep the house cool is to avoid appliances and fixtures that heat it up. Turn lights off when not required (lightbulbs produce more heat than sunlight), shut down the computer when not in use (another heat-producing culprit), and opt for microwave cooking or barbecue grilling instead of using the stove.
Use a fan. Aside from the conventional floor and tabletop versions, there are three other types of fans to consider. Ceiling fans - now available in energy-efficient models, which use as much electricity as a 100-watt bulb - lower cooling bills even further if used only when a room is occupied. Exhaust fans - such as those in the bathroom and above the stove - work wonders to rid the air of humidity after showers and cooking. Furnace fans or whole-house fans are another cooling option, as they circulate cooler basement air to the warmer levels of a house.
Last resort. If you're still compelled to turn on the air conditioner, set the thermostat three or four degrees higher than usual. Surprisingly, you won't notice the difference.
