Without air conditioning, Phoenix, the capital of Arizona at the gateway to the Sonoran Desert, would not be the fifth most populated city in the United States today. Even Disney World Orlando could not have become the second largest tourist destination in the world, despite being located in hot and humid Florida. The invention to calm the thermometer that paradoxically contributes to global warming due to its energy consumption has allowed the development of cities in the southern United States, the area known as the Sun Belt, which includes up to 18 states.
“It’s the single most important factor in moving people to areas that otherwise wouldn’t have been able to support it,” Robert Fishman, professor emeritus of architecture and urban planning at the University of Michigan, said via video call. “A very important aspect, besides the comfort of housing, is that it allowed factories and offices to continue operating during incredibly hot summers,” he said.
In 1999, the academic conducted a study that is still cited today on the ten main variables that influenced the development of the American city in the second half of the 20th century: air conditioning appeared in ninth place behind highways, cars, shopping malls and residential suburbs, among others. As for southern cities, Fishman points out, the combination of mild winters, air conditioning in the summer and relatively cheap housing is the perfect combination that has won over so many Americans. The three most populous states in the country are located in the Sun Belt: California (38 million inhabitants), Texas (28 million) and Florida (21 million).
On the other side of the scale, there is the price imposed by this technology, which is becoming more and more essential rather than a luxury: air conditioning is the household appliance that consumes the most energy. Worldwide, it represents 10% of electricity. And much of this energy has been obtained by burning fossil fuels, which are the main cause of global warming. With the increase in heat waves linked to the climate crisis, it is expected that in the coming decades, the number of appliances in the world will triple, increasing the pressure on the electricity grid.
Over the past decade, there have been 60 percent more power outages in the southern United States due to heat incidents than in the previous decade, according to the organization Climate Central. In China, in recent years, records have been broken for electricity generation due to demand for air-cooled appliances as temperatures spike that have strained the country’s power grids. Climate shelters are the response that many governments are providing to extreme heatwaves. And the usual shelters are rooms with air conditioning on high.
Global warming has also meant, for example, that in Spain the need for cooling buildings has doubled since 1979. Eurostat data shows that to maintain what they call the “comfort temperature” it is necessary to use a certain “air temperature” air conditioning system. The data is consistent “with the perception that it is getting hotter every summer,” Aemet explained.
The same thing that has been recorded in Spain is happening in countries of the European Mediterranean basin such as Cyprus, Malta, Greece or Italy where the heat severity index increases by more than 100%, according to Eurostat. And the greater the severity, the more it is necessary to cool the air. In fact, the Mediterranean region is the second most affected by the climate crisis in the world after the Arctic. The waters of the Mediterranean Sea are warming 20% faster than the rest of the planet.
Historian and University of South Florida professor Raymond Arsenault argues in his award-winning essay The End of the Long Hot Summer: Air Conditioning and Southern Culture (1984), that the so-called “revolution” of this invention was in reality “an evolution that occurred in different waves. By the 1970s, this activity had even extended to stables, chicken coops and greenhouses.
From his home in St. Petersburg, Florida, the author points out that this invention “has blunted our sense of time.” Regulating the climate in the indoor spaces we move through and in some outdoor spaces, like the air that cools people waiting in line at Disney World, Arsenault points out, “allows us to almost ignore” the seasons of the year and has “weakened the connection to nature and warmth” that characterized southerners.
Controlling one’s temperature “is no longer seen as a privilege, but as a right,” he says, “even though it is barely used in many parts of the world.” China and the United States are the main consumers. According to the International Energy Agency, there are about 2 billion air conditioning units worldwide, 70% of them in homes.
This has blunted our sense of time. It allows us to almost ignore the seasons of the year and has weakened the connection with nature and warmth.
Raymond Arsenault
— Professor at the University of South Florida
From printing to cinema
Although the air conditioning system was invented in the North, its initial development took place in the South. In 1902, the young engineer Willis Carrier accidentally managed to lower the temperature of the Brooklyn lithographic press, his goal being to stabilize the humidity that was affecting the paper; Over the next 20 years, it would be used in the cotton, tobacco, paper, beer industries… to improve production. By controlling temperature and humidity, the consistency of product manufacturing was maintained regardless of the time of year or time of day.
In the late 1920s, it entered the cinemas, thanks again to the improvements made by Carrier, who led the industry until his death in 1950. Some say that the golden age of Hollywood owes part of its success to this invention that attracted an audience eager to temporarily escape the stifling summer heat to the theaters. In the 1940s, temperature control devices replaced ceiling fans in department stores and, ten years later, they were installed in hotel rooms. By this time, and after overcoming the opposition due to epidemics caused by ventilation systems, new hospitals were already equipped with temperature control systems. One of the ideals of modernist architects like Le Corbusier, which was to isolate skyscrapers from the outside environment, was not really feasible until the advent of air conditioning.
The size and price had kept these systems out of reach of the average citizen until after World War II, when cheap windows appeared, accompanied by a marketing strategy aimed at promoting them as a symbol of modernity and status. Sales soared and have continued to grow. By 1960, 13% of homes were air-conditioned, compared to 55% of homes in 1980 and 90% today. In Europe, by contrast, the number of users is 20%.
“One of the most surprising things in my life, and I was born in 1946, is how dramatically the cost of air conditioning has dropped. When I was growing up, even middle-class families like mine might have had one in their living room. Most new homes now have central air conditioning. Window units are incredibly cheap. The relatively poor can afford one for a small apartment,” Fishman says.
Urban planning conditions
The rise of air conditioning marked a turning point in building design and urban planning. “It accelerated the withdrawal, especially in the American home, which was much more open, with its famous porch needed to catch the breezes and where you spent a lot of time in the summer facing the street, seeing the neighbors. Now, in front of the house is the garden with its lawn that is always empty. People are withdrawing much more indoors than before,” Fishman says.
The notions of orientation, location, and spatial design in the home, so important to good architecture, became irrelevant in the construction industry, which was more interested in meeting the growing demand with uniform designs for single-family homes that could be built quickly and cheaply, giving rise to a suburban landscape that extended from the urban center of skyscrapers and office buildings. Cities such as Houston, Miami, Las Vegas, and Atlanta experienced above-average growth in the second half of the 20th century. The population of the Southern states increased from 28 percent in 1950 to 40 percent in 2000.
“American houses, with their wooden structures, were very light compared to European masonry houses, partly because the fuel, coal or oil, was very cheap. We applied the same philosophy to air conditioning,” Fishman explains. “It makes no sense to concentrate the population in places like Las Vegas or Phoenix, where you’re going to have intensive use of energy, water and other resources. But the American philosophy is to keep building.” In Phoenix, new housing projects that rely on groundwater have been paralyzed since last year because, according to predictions, given the climate crisis, there are not enough resources to fuel continued growth.
It is the most important factor in the movement of population to areas that otherwise could not have supported it.
Robert Fishman
— Professor Emeritus of Architecture and Urban Planning at the University of Michigan
Undeniable advantages
The benefits of air conditioning in reducing deaths from extreme heat, improving working conditions and the operation of hospitals and schools, increasing productivity and living standards are undeniable. And, even if equipment becomes less polluting, indirect CO2 emissions related to the energy needed to operate it increase, contributing to the increase in temperature and a greater reliance on refrigeration systems.
There are passive strategies for reducing temperature, such as natural ventilation, the use of vegetation or the creation of shade, used by ancient Middle Eastern civilizations that contemporary sustainable architecture draws inspiration from to minimize the use of cooling and heating. However, Robert Fishman believes that societies like the United States “are so tied to high energy consumption” that the only hope for reducing the impact of air conditioning on the climate crisis lies in “the enormous technological advance of renewable energy.”
For Raymond Arsenault, sitting at his desk under two ceiling fans that reduce the use of air conditioning, he believes in moderating the consumption of cooling systems. Even if he knows it won’t be easy. “For many people, air conditioning is as essential as food.”
