It is no secret that air conditioners require a lot of energy. There are often power outages during the hottest weather simply due to the incredible demand on electrical grids, particularly to power air conditioners. During a heat wave in 2003, eight northeastern states and areas of Canada experienced a blackout for two days due to the overwhelming power demand. A surge in demand increases the use of the electrical generation, which is primarily the burning of fossil fuels.
The burning of fossil fuels and the use of certain chemicals to manufacture and run air conditioners contribute heavily to greenhouse gases. The EPA in its paper called “Ozone: Good Up High, Bad Down Low” explains that the use of fossil fuels and chemicals like CFCs (chlorofluorocarbons) in air conditioning contributes to increasing the ozone concentration in the troposphere--the layer of the atmosphere closest to Earth's surface. At this level, ozone is "bad"--the main component of smog. This increases the temperature lower to Earth while damaging the protective ozone layer above the stratosphere, making greenhouse effects even more dramatic.
Indoor Air Pollution
The quality of indoor air can be ruined if mold and other allergens are introduced into the environment without filtering it out. Mold, once introduced into an air conditioner, can cause its increase and spread, according to the Centers for Disease Control and Prevention. Mold can cause anyone in the environment—plants, animals and humans alike—to experience various illnesses. Symptoms in animals and people can include dizziness, nausea and breathing problems. Viruses such as the common cold and influenza can also be reintroduced into the home through air conditioning as well.
Another environmental impact of air conditioners comes from the social isolation air conditioners can create. People in hot environments crank the air conditioner up and might venture out only to head to another air-conditioned area. People become socially isolated from their neighbors due to the air conditioning. This impacts the environment by feeding the simultaneous use of multiple air conditioners instead of a few being run while people socialize in central locations. Air conditioning can also prevent people from socializing outside in the shade or at local bodies of water in favor of the cooler indoors.
Lowering the impact home air conditioners have on the environment is not as daunting as it may appear. First, the EPA recommends using only Energy Star certified air conditioners, which drastically reduce the amount of electricity needed to run an air conditioner by around 30 percent. Use a timer for the air conditioning unit to make sure you are minimizing energy use when people are not home. Open the windows at night instead of using the air conditioner to enjoy the cool night air and further save energy. In arid areas, consider a swamp cooler, which uses only a quarter of the energy an air conditioner does.