A new study suggests that shifting to electric vehicles (EV) could help improve the overall air quality in cities and lower carbon emissions.

Researchers from the Northwestern University in Evanston, Ill., compared the air pollution generated from battery-powered EVs and the vehicles with internal combustion engines. They found that even as EVs used combustion sources to produce electricity, the vehicles still have a net positive impact on air quality and climate change, Phys.org has learned.

"One technologically available solution is to electrify our transportation system,” Daniel Horton, senior author of the study and an assistant professor of Earth and planetary sciences at Northwestern University, said. “We find that EV adoptions reduces net carbon emissions and has the added benefit of reducing air pollutants, thereby improving public health."

For the study published in the journal Atmospheric Environment, Horton’s team used an emissions remapping algorithm and air quality model simulations to assess the impacts of vehicles on the environment. 

The researchers examined the two common pollutants, ozone and particulate matter, that have been linked to automobiles and power emissions. Both pollutants have also been associated to development of a variety of health problems, such as asthma, emphysema and chronic bronchitis.

For the analysis, the team took into account the potential electric vehicles adoption rates generation of electric vehicle power supply, geographical locations and seasons and times of day.

"Across scenarios, we found the more cars that transitioned to electric power, the better for summertime ozone levels," Jordan Schnell, one of the researchers and a postdoctoral research fellow at Northwestern University, said. "No matter how the power is generated, the more combustion cars you take off the road, the better the ozone quality."

Ozone levels decreased across the board in simulations of warmer weather months but went high during the winter. But the levels of particulate matter or haze were lower in the wintertime. But the areas with clean energy sources or more EVs had drastic reductions in human-caused haze.

"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.”