Here are 5 easy-to-employ, eco-friendly strategies to help you keep the temperature at a comfortable level while you cut air conditioning (AC) costs and pride yourself on protecting the planet...
Keep It Out. Thick or insulated walls, shade trees, deep eaves, and window awnings are all useful for making sure that conducted heat doesn't make it indoors. Most of the sun is going to be hitting your roof, so it is particularly important to make sure your roof is both heavily insulated and highly reflective.
Move It Through. Many hot climates have weather patterns that can be used to cool your home. Many coastal areas for example, have a predictable onshore sea breeze. Funnel that breeze into your house, and it will flush heat out of it on the other side. Planting a hedge or a row of trees in a strategic place can help funnel cooling winds into your house.
Dry climates, especially, tend to have distinct temperature drops at night. Take advantage of this by opening your lowest windows and your highest, creating a convection "chimney effect" that sucks cool air into the lower part of your house from the outdoors while heat escapes up and out through the upper story. This strategy effective cools your entire domicile. Clerestories and operable skylights are excellent for increasing this effect. Attic vents are also a basic element of convection cooling.
Spin It 'Round. If your natural ventilation needs a boost, use circulating fans. Ceiling fans circulate the air of an entire room, and there are fans for jobs of every size. While they work best with high ceilings, proper placement can greatly enhance the effectiveness of fans at any height.
Attic fans exhaust air from the very hottest and highest part of the house, providing substantial heat relief through convection. Your roof is a great place for a solar fan, powered by photovoltaic cells. Because they run fastest when the sun is hottest, these fans are ideal for this application. If you live in a climate with many cloudy hot days, however, you should provide grid-powered back-up.
A whole house fan is a workable substitute for air conditioning in most climates. Sometimes existing central heating and cooling ducts can be used along with a whole house fan. These fans need to be appropriately sized, require dedicated wiring, and, usually call for an enlarged venting system in the attic. Unlike other fans, they are therefore typically professionally installed. The Department of Energy's Consumer Guide has a great overview of whole house ventilation.
Wet It Down. In low-humidity climates it is much easier to solve the heat problem: just get wet. Evaporation is cooling, which is the principle of perspiration. Evaporative coolers, also known as swamp coolers, use this principle too. They are simple machines that cost about half as much to install as air conditioning, use a quarter of the electricity, and do not require ozone-depleting refrigerants. However, they need monthly (though easy) maintenance during peak use, and they only work well in dry climates.
Swamp coolers have a small motor that pumps water from the bottom of the cooler to the top, where it falls down the sides of absorbent pads. Another motor runs a fan pulling outdoor air through the pads, cooling it 15 to 40 degrees F, and then into your home. Unlike air conditioning systems, coolers provide a constant flow of fresh outdoor air.
They can be installed on roofs or on the ground floor (which makes maintenance easier). There are whole-house and room-sized coolers available. Newer, more efficient two-stage or indirect evaporative coolers incorporate a secondary heat exchanger to reduce the humidity released into the house. Read more about evaporative coolers at ToolBase Services to learn more about evaporative coolers.
Use the Night. Where night temperatures drop substantially, nocturnal radiative cooling is particularly effective. Opening your windows at night, as mentioned above, is one component. The other requires some thermal mass in the building, such as a concrete slab floor, plaster walls, or passive solar water walls. These serve as heat sinks during the day, keeping the house cool. At night they release their heat as cool air passes over them.