With summer's sweltering heat upon us, air conditioners blast to beat the heat; however, there are more efficient ways cool your home or at least reduce the reliance on an A/C unit. With no energy bill and little maintenance, passive cooling is the most efficient way to handle the summer months. After exhausting passive cooling strategies, efficient active cooling techniques can be applied to cool your home. This summer, implementing energy efficient alternatives to wasteful air conditioning units will save you both money and energy.

Passive Cooling

One effective way to keep your home cooler is to draw the shades or blinds during the day. Honeycomb blinds work to reduce heat buildup by blocking direct solar light, which can heat a room up very quickly. Blinds are also available with built-in reflective materials that control heat and light penetration. In addition to blinds, window overhangs block direct rays from above, allowing in natural ambient light with less heat.

Passively ventilating a home is a zero-cost way to increase the comfort level in a house. Opening windows throughout a house while ensuring that there are no closed doors to prevent airflow allows a gentle breeze to blow across the interior spaces. This breeze alone can lower the perceived temperature up to 7° F (Lechner, Heating, Cooling, and Lighting: Design Methods for Architects, Second Edition, pp 268).

Using trees to shade windows is another natural way to increase the comfort of your home during the warmer months.  Planting deciduous trees on the south side of your home will aid in keeping the roof cool,but in climates where heating needs prevail, south-facing windows should have unobstructed access to full winter sunlight. For any climate, planting trees with foliage lower to the ground on the west side of your home blocks the hot, late afternoon sunlight.

Healthy Active Cooling       

While passive cooling techniques reduce energy consumption most effectively, some climates require additional cooling methods. Evaporative cooling, whole-house fans and ceiling fans are common energy efficient alternatives to a typical air conditioning unit.

Evaporative coolers, often termed "Swamp Coolers," use simple evaporation to cool the air inside your home. They work best in dry climates such as the western and southwestern United States. 

A direct evaporative cooler guides outside air through a drenched, porous pad where it is cooled, humidified, and filtered. This, unlike a typical air conditioner, adds humidity to the air. An Indirect Evaporative Cooler uses an additional heat exchanger to remove humidity, but uses more energy than a Direct Evaporative Cooler.

Another efficient cooling method is a whole-house fan. According to the Department of Energy, a 2-ton air conditioning unit running in Atlanta, Georgia costs approximately 20 cents/hour, while a whole house fan only costs 1 to 5 cents/hour to run. This is because an air conditioning unit constantly works to maintain a specific temperature. A whole-house fan draws in cooler morning and evening air through the windows. Hot air that accumulates during daytime hours is extracted through the attic. Since the morning and evening are the times of high occupancy for most families, it is not always necessary to have a high capacity air conditioning system running for peak daytime heat, when homes are typically unoccupied and when electricity rates are the highest.

If you want to avoid the installation of a new system, a well-running, properly installed ceiling fan may be the answer. According to DIYnetwork.com, a simple ceiling fan can save you up to 40% of energy costs during the summer and 10% during the winter. In the summer, the "wind chill factor" of a ceiling fan makes a hot room bearable with minimal energy use. In the winter, a fan will move valuable warm air from the ceiling to ground-level. For more information on getting the most out of your ceiling fan, visit DIYNetwork.com

Conclusion

Carefully implementing the use of both passive and active cooling techniques can greatly reduce the cost of cooling and unnecessary energy consumption. For those looking for simple solutions, window overhangs and blinds may be the option to consider.  For others that require additional improvement, a more-active solution, such as a whole house fan or evaporative cooler may be a consideration.  All of these options will ensure a more comfortable home during some of the hottest months of the year and, at the same time, reduce your energy consumption and cooling bills.