Production and use of greenhouse gases are the biggest environmental impacts of air conditioner use.

Photograph by Maksud/Shutterstock

Environmental Impact

Energy Use

The electricity generated to power air conditioning carries both global and personal health consequences. In burning fossil fuels such as coal to supply electricity to homes and workplaces, power plants discharge clouds of soot and other pollutants into the atmosphere. Among these are mercury and carbon dioxide (CO2). Air conditioner use in the U.S. results in an average of about 100 million tons of CO2 emissions from power plants every year.


Formerly used as cooling agents, ozone-depleting chlorofluorocarbons (CFCs) have been replaced by hydrochlorofluorocarbons (HCFCs), which deplete 95 percent less ozone. However, booming demand for air conditioners in hot climates such as India and China has upped the chemical's output in developing countries 20 to 35 percent each year, causing damage at an alarming rate and possibly setting back ozone recovery by 25 years. In industrial countries, HCFCs are being replaced with ozone-safe cooling agents and will be banned in the U.S. by 2010. But HCFCs will be allowed in developing countries through 2040, and because they're still cheaper to use than ozone-safe chemicals, production in developing countries is expected to increase fivefold by 2010.


Federal law requires that HCFCs be recovered from air conditioners and other appliances before they are dismantled for recycling or tossed in landfills, and the EPA is authorized to impose fines of up to $25,000 for failure to comply with regulations. Before discarding your old unit, search for a company that is EPA-certified to recover HCFCs. Share the Air has certified companies listed by region.

Personal Health

In the midst of sweltering heat waves, air conditioning can be a lifesaver, protecting against heat stroke and hyperthermia. But, without proper maintenance, air conditioners can also be a health hazard. Dirty filters can allow allergens, pesticides and other particulate matter to enter your home from the outside, posing threats to indoor air quality. Exposure to those pollutants can trigger a host of health problems, including allergies and asthma and eye, nose and throat irritation.

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