The Effects of The Use of Air Conditioners in Locations with Hot and Warm Climates

With many developing nations becoming more wealthy, a report by the Lawrence Berkeley National Laboratory estimates that by 2050, there will be 1.6 billion new air conditioners installed. The concerns about this mostly revolves around the increased electricity production and the greenhouse gas emissions that come with it. What is rarely discussed are the unintended consequences of modern cooling and heating. In an effort to maximize energy efficiency, buildings are designed to be completely sealed off from the outside world, with only ventilation ducts to exchange air in and out of buildings. The design of air conditioners create the perfect environment for the growth of potentially harmful microbes. In sweltering climates, modern cooling and efficient building designs have made life much more convenient and comfortable, but may have also been the cause of some negative health effects.

The 1973 oil crisis sparked a movement in building architecture to maximize energy efficiency. Insulating buildings and sealing every crack to prevent air leakage became normal. Buildings that did not have sufficient ventilation reported an increase in illness reported by its occupants. It is believed that volatile organic compounds, from ceiling tiles and carpets that would normally would have been filtered out through windows or proper ventilation, were making people sick in what would be referred to as sick building syndrome or tight building syndrome. Other factors contributing to this syndrome included poorly designed and located intake vents, that may have been taking in and exposing building occupants to harmful substances like formaldehyde, asbestos, and lead paint.

Air conditioning units not only cool the air, but act as dehumidifiers. Water droplets get collected on the evaporator coils and then drip down into the drain pan. The moist and hot environment of the air conditioner makes it ideal for the growth of bacteria and mold. Some of these microbes may be blowing back into your house along with the cool air. Office buildings with air conditioning systems are associated with up to a 200 percent increase in respiratory ailments compared to buildings with natural ventilation. Legionnaires disease is most commonly linked to the symptoms associated with the use of air conditioners. It is caused by the inhalation of aerosolized water containing Legionella bacteria and common symptoms include a dry cough, high fever, headaches, and shortness of breath.

Proper ventilation systems are crucial to countering the issues of poor indoor air quality. It is important to seal air leakage to remain energy efficient, but buildings should be designed with natural ventilation through traditional windows. When the temperature is mild, cracking the window instead of relying on central cooling and heating can properly ventilate the building. HEPA air filters can be used when central cooling and heating and air flow isn’t optimal for proper ventilation Avoiding the use of harmful building materials that are high in volatile organic compounds. Some air conditioning units are built with coils that are resistant to microbes and utilize filters to prevent microbe proliferation. With the increase in greenhouse gas emission and air pollution, the increase in air conditioner usage could be a deadly combination in developing areas that are already dealing with poor air quality.

Most of the world live in areas with warm and hot climates. Air conditioning use is expected to increase dramatically and electricity consumption will rise as a result. This could lead to increased air pollution, which is already causing the deaths of an estimated 5.5 million people globally. Indoor air quality is also expected to decrease with air conditioning recirculating stale air and the lack of proper ventilation. Some of these issues can be eliminated with proper ventilation, use of air filters, and improved efficiency and design of air conditioners. It is unlikely anyone will forego the use of air conditioners, so people will need to be made aware of potential issues with indoor air quality.