Electric vehicles don’t produce tailpipe emissions, but there are other factors to consider when judging their environmental impact. Manufacturing is a big one, as well as where their electricity comes from. This is often used as an argument by naysayers against the environmental benefit of EVs, but a new study reaffirms that, yes, a car that doesn’t spew pollutants as it’s driven is in fact the lower-emission option.
The said study was published in May in the Environmental Research Letters journal. The headline stat is that EVs can reduce emissions by 40-60% compared to internal-combustion vehicles “in most locations.” However, the exact amount of emissions reductions depends on several factors, the most important being the composition of the local grid where they’re being driven. Coal-fired power plants increase the effective emissions of the EVs charged with the power they generate, but the reverse is also true of renewable alternatives.
“The electricity mix is the most important contributor to these regional variations,” the study’s abstract reads, “leading to more uniform and greater emissions reductions if the electricity supply decarbonizes.”
The Union of Concerned Scientists has been saying the same thing for over a decade. It’s been tracking real-world EV emissions in the U.S. since the dawn of the modern EV era, showing how they have decreased as the grid has gotten cleaner. Right now, the average EV in the U.S. has emissions equivalent to a 96-mpg gasoline car, per to the UCS. The organization has an online tool that lets you see the estimated emissions of a given year, make, and model in your ZIP code—handy for any potential EV purchase.
Driving patterns also have a big impact, according to this new study. Researchers found that urban driving was better for maximizing emissions reductions than rural driving. In consistent urban driving, plug-in hybrids could apparently achieve 80-90% of the emissions savings of all-electric vehicles, assuming they’re regularly charged and driven in electric mode. That drops to 60% in rural areas.
This would mean that, assuming high mileage and lots of urban driving, local governments or fleet operators looking to reduce emissions need only achieve 9% EV adoption for a 10% emissions reduction. A fleet with lower annual mileage but more rural driving would need 42% EV adoption to achieve that same level of emissions savings. In contrast to the electricity mix and driving patterns, local climate “has a more moderate effect” on relative emissions, according to the study.
No emissions reductions will happen if people don’t buy EVs, and on that front, the study has some good news. EVs are cost-competitive with internal combustion “in many locations and for many people,” researchers said, with the main factor being the cost of electricity compared to gas prices. The arrival of less-expensive EVs like the Slate pickup and its Ford rival should make the cost picture look even better for at least some shoppers.
Read the full article here