next two decades, users of all types continued to increase their reliance on air conditioning. Across the country, most new office buildings, hotels, hospitals and retail stores featured central air systems. In the South, the percentage of residences with that feature increased from the aforementioned 18 % in 1960 to more than 50 % in 1970. Indeed, the widespread availability of air conditioning throughout the Sunbelt( the South, spanning from the East to West Coasts) was an important enabling factor behind that region’ s economic growth in the period.
The region first labeled the Sunbelt in 1969 had long been the home to many military installations and defense contractors’ manufacturing facilities. During the next two decades, the availability of central air conditioning was an important factor in encouraging other types of manufacturers to relocate existing plants from other states and / or establish new facilities throughout that region. In cities such as Dallas, Houston and New Orleans, developers began building air-conditioned office skyscrapers to attract white collar businesses as well. From 1960 to 1980, both population and employment numbers grew faster in the southern tier of the country than in the northern tier. By 1980, the Census Bureau showed air conditioning in 58 % of all homes in the country, but in an average of 75 % of all homes in the three southern census divisions. But the penetration rate remained uneven throughout the period. It was closer to 5 % in older, low-income neighborhoods in cities such as Chicago and New York, where the existing electrical wiring systems made the addition of air conditioning units quite problematic.
Problems Emerge
In addition to providing relief from heat and humidity, air conditioning helped reduce the nationwide mortality rate from heat-related conditions and improved worker productivity in both offices and factories. But it was not without side effects. In 1962, the Federal Power Commission estimated that the peak load of electricity demand would reach 494 million kilowatts by 1980. In 1969, it updated that forecast to 555 million kilowatts, largely due to the increasing use of air conditioning. Throughout the 1960s, that increased usage put a serious drain on the electric infrastructure in cities across the
Title page of the first edition of the Engineers Hand-Book, edited by Willis Carrier while at the Buffalo Forge Company, 1914.
country, leading to numerous brownouts or dim-outs during periods of unusually hot weather.
The decade of the 1970s was a tough one for the air conditioning industry. The 1973 Arab oil embargo that caused the nationwide energy shortage led Presidents Richard Nixon and Jimmy Carter to order limits on air conditioning in public buildings. In 1974, the Commerce Department required manufacturers of air conditioners to include information about their energy consumption.
Perhaps not coincidentally, the environmental movement began in the early 1970s. Scientists examining changes in the Earth’ s upper atmosphere implicated chlorofluorocarbons( CFCs) as major contributors to the thinning of the protective ozone layer. They also identified Freon( the most widely used refrigerant in air conditioners) as a particularly damaging CFC. The government removed that propellant from aerosol cans in 1978. But it took another dozen years before manufacturers stopped using Freon in new air conditioners.
And in one final insult, in January 1977, officials at the Center for Disease Control discovered that a previously unknown bacteria they labeled Legionella pneumophilia had been quietly and invisibly reproducing in the cooling water of an air conditioning system in the Bellevue-Stratford Hotel in Philadelphia. But the discovery occurred six months after that organism’ s circulation had been responsible for more than 200 cases of pneumonia and 34 deaths among the 2,000 men attending the annual convention of the American Legion at that location. Investigators then discovered that previous outbreaks of the pneumonia later termed Legionnaires’ disease had occurred from 1965 to 1974, resulting in more than 100 infections and 18 deaths. Building superintendents nationwide thus became acquainted with problems related to the overly mechanical production of air that they labeled“ Sick Building Syndrome.”
By 1980, air conditioning was present not only in the great majority of homes and commercial buildings, but also in automobiles, airplanes, trains and even subways. Over the next several decades, manufacturers developed units that were more energy efficient, less environmentally damaging and more affordable than before. Users of all types acknowledged the technology’ s negative aspects and learned to pair its usage with passive cooling techniques. Living without this method of producing“ manufactured weather” is no longer a viable or desirable option.
Michael A. Martorelli is a director emeritus at Fairmount Partners in Radnor, PA, and a frequent contributor to Financial History. He received his MA in History from American Military University.
Sources
Ackerman, Marsha E. Cool Comfort: America’ s Romance with Air-Conditioning. Smithsonian Books. 2010.
Arsenault, Raymond.“ The End of the Long Hot Summer: The Air Conditioner and Southern Culture.” The Journal of Southern History. Vol. L, No. 4. November 1984.
Basile, Salvatore. Cool: How Air Conditioning Changed Everything. Fordham University Press. 2014.
Biddle, Jeff E.“ Making Consumers Comfortable: The Early Decades of Air Conditioning in the United States.” The Journal of Economic History. Vol. 71, No. 4. December 2011.
Cooper, Gail. Air-conditioning America: Engineers and the Controlled Environment, 1900 – 1960. The Johns Hopkins University Press. 1998.
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