Study finds air conditioning can increase nighttime temperature by 1 degree Celsius

Jun 9, 2014 11:35 GMT  ·  By
Air conditioning units now said to be driving up temperatures in urban areas across the US
   Air conditioning units now said to be driving up temperatures in urban areas across the US

In what might be today's most ironic piece of news, researchers with the Arizona State University in the United States claim that, according to their investigations, air conditioning units are making cities in the United States hotter.

More precisely, they say that, provided that their calculations are correct, air conditioning units that are up and running in urban areas in this country are adding as much as 1 degree Celsius to nighttime temperatures.

As detailed by The Guardian, this claim is based on information obtained while researching a simulated 10-day period of abnormally hot weather between 2009's July 10 and July 19. The focus was on the impact of air conditioning on overall temperatures.

“Our work demonstrates 1C degree local heating of urban atmospheres in hot and dry cities due to air conditioning use at night time. This increase in outside air temperature in turn results in additional demands for air conditioning,” says specialist Francisco Salamanca.

In a paper in the Journal of Geophysical Research Atmospheres, Francisco Salamanca and fellow researchers detail that air conditioning units drive up local temperatures in an area where they are installed because they emit waste heat from offices and apartments.

During the day, this waste heat goes unnoticed due to the fact that the air outside is too hot for anyone to figure out that there is another heat source in town. After the sun sets, however, this extra heat can no longer be ignored, the Arizona State University specialists say.

It is estimated that, for the time being, about 87% of the households in the United States are equipped with one, maybe even more air conditioning units. As if the extreme weather brought about by climate change and global warming were not enough, these systems help make even urban areas even hotter.

The good news is that, the way the Arizona State University scientists behind this research project see things, one need not necessarily unplug their air conditioning units to make sure that they no longer contribute to off-the-charts nighttime temperatures.

On the contrary, it appears that one very simple solution to this problem is figuring out a way to collect the waste heat emitted by these devices and put it to better use. For example, the heat could be used to power water heaters.

“Sustainable development and optimisation of electricity consumption would require turning wasted heat from air conditioning into useful energy, which can be used inside houses for various purposes,” explains Francisco Salamanca.