The power of air conditioning. How to turn it down?

By Daniel Nunez Gonzalez

One of the cases in the course involved Zhang Yue’s Broad Group and the emporium he built by first developing a non-electric chiller unit in China. The case reminded me of the role of air conditioning in recent demographic and urban trends, and in the consumption of energy and resources. Lee Kuan Yew, former PM of Singapore, called air conditioning the “greatest invention of this century” [1]. The generalization of affordable systems in the 1970s was a major factor in the growth of the Sun Belt in the United States.

South Bridge Road, Singapore. Pre and post-air conditioned construction in the tropical city-state. Credit:

Air conditioning’s popularization has led to perverse effects. For decades, cheap energy made customers and builders worriless about energy savings. Today, buildings account for 39% of the CO2 emissions in the United States; higher than transportation at 26% [2]. Air conditioning has a major effect in temperature in large cities, contributing to the “heat island effect”; in a warm day in Paris, the effect of chiller systems alone can increase the average temperature by up to 2 degrees Celsius [3]. Black-outs due to excessive electrical demand are now commonly related to heat waves, when the demand for air conditioning peaks.

Global demand is expected to explode. Only two of the warmest 30 largest metropolitan areas in the world are in developed countries. 2% of Indian households owned one air conditioning unit in 2007, compared to 87% of the US [4]. Popularization of air conditioning in the developing world will only contribute to more energy consumption and, ultimately, to climate change.

Credit: Sivak, M. “Potential energy demand for cooling in the 50 largest metropolitan areas of the world: Implications for developing countries”, The University of Michigan, Transportation Research Institute, August 24, 2008.

What can be done to avoid those developing countries consuming indiscriminate resources, without falling into the cliché of Western nations blaming them about the increase in pollution?

In my opinion, governments, specifically in emerging large markets like India, that could effectively have an impact in the specifications of a product, should enforce stricter efficiency standards. Citizens should be informed about additional savings with more efficient A/C units, adopting schemes like the EU energy label system. Building regulations could be tightened, particularly in major projects where the increases in construction costs could be carried over by medium and long-term savings in consumption.

Buildings in temperate areas should rethink whether air conditioning is actually necessary. Architect Perkins + Will got rid of a mechanical air conditioning system in the renovation of their own office in Seattle, a city with only a few days of intense heat per year, to adopt a natural ventilation system [5].

There is also a cultural aspect about air conditioning. The standard “thermal comfort” temperature tends to be higher in the United States than in Europe. In an extreme case, after the Fukushima earthquake and the reduction in energy production, the Japanese government and corporations prescribed higher indoor temperatures, of up to 28 degrees Celsius [6].

Ultimately, there are several factors that must be addressed by different players: governments, with their power in regulation and taxation; corporations and their ability to develop more energy-efficient systems, and the society and its environmental awareness.


[1]: McCarthy, T. “Lee Kuan Yew”, Time, August 23, 1999.

[2]: US Green Building Council, “Buildings and Climate Change”, retrieved at

[3]: de Munck, C., Pigeon, G., Masson, V., Meunier, F., Bousquet, P., Tréméac, B., Merchat, M., Poeuf, P. and Marchadier, C. (2013),

“How much can air conditioning increase air temperatures for a city like Paris, France?”

[4]: Rosenthal, E. “The Cost of Cool”, The New York Times, August 18, 2012.

[5]: Webert, M. “Perkins + Will spruces up its digs”, November 26, 2006, retrieved at

[6]: McMahon, J. “How Japan Discovered Conservation: Fukushima”, Forbes, January 6, 2013.