Ventilation

Providing fresh air flow into a house is a low-cost and potentially energy-efficient way to cool a home and maintain good indoor air quality. In good weather, natural ventilation (when air moves through windows or doors) can suffice for cooling. On some days, the air temperature at night is pleasantly cool and letting this air into the house during the night can significantly cool down a house after a warm day. Natural fresh air ventilation can also be supplemented by a number of low-energy mechanical ventilation devices that can help. These include:

    * Ceiling fans - Ceiling fans are a useful alternative to help keep you cool while reducing or eliminating the need to use air conditioning. Typically a ceiling fan consumes much less electricity than does a central air conditioner. A ceiling fan doesn't cool or de-humidify a room - it only cools you through a wind-chill effect against your skin. Ceiling fans are also inexpensive to purchase. Make sure, however, to turn your fan off when you leave the room. If you are not there to feel the cooling air movement on your skin, continuing to operate the fan only wastes energy.

    * Window fans - Window fans can also help to cool down your house in lieu of running your central air conditioning. A box fan, or other type, placed in an open window can blow cooler outside air into a room, or set in reverse, can draw cool air in through other windows and throughout the entire house. This, of course, is best done when the air outside has cooled down, such as in the evening, yet the air inside the house is still warm. Humidity conditions, pollen, dust and other factors will need to be considered when using this approach. A window fan, or portal box fan or fan on a stand can also be used in a fashion similar to a ceiling fan to blow air against your skin to create a wind chill cooling effect.

    * Whole-house fans - Whole-house fans help cool your home by pulling cool air through the house and exhausting warm air out of the house. Typically these are very large fans installed by professionals in the attic of a home. They are most effective when operated at night and when the outside air is cooler than inside. However, allowing them to continue to run when outdoor temperatures are hotter than indoors, defeats the purpose and will waste energy. Again, humidity conditions, pollen, dust and other factors will need to be considered when deciding to use this approach.