Palmer added that policymakers were also muddled about the problem they are trying to mitigate in the first place.
“Are we trying to solve clean air? In this case, ban diesels. Or are we trying to solve CO2? In this case, you need to use less fossil fuel,” he said. “The two are different. And a lot of the dialogue right now is mixing those messages.”
Cars that run on fuel produce carbon dioxide along with other greenhouse gases. Diesel vehicles, however, emit more pollutants, such as soot and nitrogen oxides, as compared with their gasoline counterparts. Those emissions can cause lung and other bodily irritations and may also induce cancer, according to the U.S.-based Union of Concerned Scientists, an independent science and advocacy organization.
Palmer added that the impending ban on sales of petrol and diesel cars still wouldn’t make it possible for the auto market to become fully electric by 2040, as he didn’t think batteries would be sufficient to power heavy vehicles.
Instead, it’s more likely that “about half the cars will be gasoline and gasoline hybrid, and about half the cars will be alternative fuel,” he said.
To be sure, electric vehicle maker Tesla announced earlier this month that it planned to launch in October a semi truck, which Reuters reported would have a range of around 200-300 miles, compared with an around 1,000-mile range for conventional models.