Get the most from your air conditioning

• Open windows and use portable or ceiling fans instead of operating your air conditioner. Even mild air movement of 1 mph can make you feel three or four degrees cooler. Make sure your ceiling fan is turned for summer -- you should feel the air blown downward. If you live in a relatively dry climate, a bowl or tray of ice in front of a box fan can cool you as it evaporates.

• Use a fan with your window air conditioner to spread the cool air through your home.

• Without blocking air flow, shade your outside compressor. Change air filters monthly during the summer.

• Use a programmable thermostat with your air conditioner to adjust the setting at night or when no one is home.

• Don't place lamps or TVs near your air conditioning thermostat. The heat from these appliances will cause the air conditioner to run longer.

• Consider installing a whole house fan or evaporative cooler (a "swamp cooler") if appropriate for your climate. Attics trap fierce amounts of heat; a well-placed and -sized whole-house fan pulls air through open windows on the bottom floors and exhausts it through the roof, lowering the inside temperature and reducing energy use by as much as third compared with an air conditioner. Cost is between $200 and $400 if you install it yourself. An evaporative cooler pulls air over pads soaked in cold water and uses a quarter the energy of refrigerated air, but they're useful only in low-humidity areas. Cost is $200 to $600.

• Install white window shades, drapes, or blinds to reflect heat away from the house. Close curtains on south- and west-facing windows during the day.

• Install awnings on south-facing windows. Because of the angle of the sun, trees, a trellis, or a fence will best shade west-facing windows. Apply sun-control or other reflective films on south-facing windows.
• Plant trees or shrubs to shade air conditioning units, but not block the airflow. A unit operating in the shade uses less electricity.

• Grown on trellises, vines such as ivy or grapevines can shade windows or the whole side of a house.

• Avoid landscaping with lots of unshaded rock, cement, or asphalt on the south or west sides. It increases the temperature around the house and radiates heat to the house after the sun has set.

• Deciduous trees planted on the south and west sides will keep your house cool in the summer. Just three trees, properly placed around a house, can save a few hundred dollars in annual cooling and heating costs. In summer, daytime air temperatures can be 3 degrees to 6 degrees cooler in tree-shaded neighborhoods.