Research published recently in the journal Atmospheric Environment adds more support to the growing field of studies pushing the environmental and public health benefits of electric vehicles. Coming from Northwestern University, the study quantified air pollution differences between electric vehicles and internal combustion engines, finding, unsurprisingly, that electric vehicles have a net positive impact on air quality and climate change.
Northwestern researchers Daniel Horton and Jordan Schnell used an emissions remapping algorithm and air quality model simulations in order to analyze how much ozone and particulate matter EVs generate in comparison to internal combustion engines. Ozone and particulate matter are pollutants produced by cars and power plants and pose a series of health concerns. Their analysis considered various factors, such as potential electric vehicles adoption rates; generation of electric vehicle power supply, including our current combustion-dominant mix, combustion-only sources and enhanced emission-free renewables; geographical locations; and seasons and times of day.
As to be expected, the researchers found that a transition to EVs lowers air pollution. "Across scenarios, we found the more cars that transitioned to electric power, the better for summertime ozone levels," Schnell said. "No matter how the power is generated, the more combustion cars you take off the road, the better the ozone quality." However, because of a chemical reaction that occurs in the winter with weaker sunlight, the researchers actually found increased ozone levels in the winter.
The opposite pattern was seen with particulate matter pollutants, with electrification increasing particulate matter during summer and decreasing it in winter, according to the authors. Yet, the researchers are quick to point out the complexity of their findings.
"We found that in the Midwest, the increased power demands of EV charging in our current energy mix could cause slight increases in summer particulate matter due to the reliance on coal-fired power generation," Schnell said. "However, if we transition more of the Midwest's power generation to renewables, particulate matter pollution is substantially reduced. In the Pacific Northwest or Northeast, where there is already more clean power available, EV adoption -- even with the current energy mix -- will decrease particulate matter pollution."
The scientists hope that their research can be a symbol of hope in the world of earth and environment news. "In contrast to many of the scary climate change impact stories we read in the news, this work is about solutions," said Horton. "We know that climate change is happening, so what can we do about it? One technologically available solution is to electrify our transportation system. We find that EV adoptions reduces net carbon emissions and has the added benefit of reducing air pollutants, thereby improving public health."