Alternative Cooling Vs. AC Units

Evaporative Cooling

• Probably the most common alternative to central air-conditioning is evaporative cooling. Individual evaporative cooling units -- sometimes called "swamp" coolers or window units -- cool individual rooms one at a time by pulling in outside air and passing it through a moist pad to cool it before circulating it throughout the room. Swamp coolers can work well, but you need multiple units to cool an entire home. When the outside air has high humidity levels, the ability of swamp coolers to cool the air it pulls in is compromised.

Natural Ventilation

• A simpler method for cooling the home is natural ventilation. When outside air is cool enough, open windows and run ceiling fans. Running the fan setting on your central air-conditioning unit can also help circulate cool air throughout the home without the increased energy demands of the automatic cooling setting. Of course, this method is only effective insofar as outside air temperatures remain comfortably cool.

Climate Control Systems

• For more large-scale settings, climate control systems using supply and exhaust ventilators, as well as convection heaters or dehumidifiers can offer a more cost-effective alternative to traditional heating, ventilation and air-conditioning systems. In 2007, the J. Paul Getty Trust tested such a system at the Hollybourne Cottage on Jekyll Island, Georgia. The tests indicated that "the alternative climate-control strategies applied at Hollybourne Cottage posed a significant savings in operational and maintenance costs over those of a conventional HVAC system: a reduction of 27 percent to 73 percent and that the "capital costs" of such a system were "approximately 5 percent of that of a typical air-conditioning system."

Other Considerations

• If energy efficiency is your ultimate goal, simple household measures can increase the efficiency of your central air-conditioning system without the need to uproot and replace the system with an alternative technology. Use drapes, window blinds and shade trees to help keep the house cool during warm weather. Install and maintain ventilation, weatherstripping, radiant barriers and other technologies to prevent cold air escaping the home. Set your thermostat between 75 and 80 degrees Fahrenheit and use natural ventilation only until indoor temperatures become uncomfortably warm.