We have previously talked about the urban heat island effect. Crowded metropolitan areas are significantly warmer than surrounding rural areas as a result of human activities. Among other things, cities fill up with cars idling in traffic and cars not only produce greenhouse gas emissions, their internal combustion engines also produce a lot of heat.
According to a new study by Michigan State University, electric cars produce only about one fifth as much heat as internal combustion cars. As a result, if a substantial fraction of gas-powered city cars were replaced with electric versions, the urban heat island effect would be reduced dramatically.
The study looked at the specifics of the major heatwave in Beijing in 2012. Replacing the conventional cars with electric cars would have reduced the temperature across the city by nearly 2 degrees, which it turn would have reduced air conditioning use by 14 million kilowatt hours and CO2 emissions by 11,000 tons a day. This of course was just one specific example and exactly what kind of temperature reductions and emission reductions would be achieved in general is difficult to calculate. However, it is clear that switching to electric cars would make a big difference.
The likelihood of getting entire cities to get rid of gasoline-powered cars any time soon is pretty slim, even in the most progressive places like the San Francisco area. And, of course, this heating effect only occurs in crowded urban environments. Nevertheless, the study does show that electric vehicles have some benefits that might not be obvious.
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Electric cars could help cool down our cities
Photo, posted April 19, 2011, courtesy of Mariordo59 via Flickr.
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Earth Wise is a production of WAMC Northeast Public Radio.