The big push over air quality in the 1990s was for reducing carbon dioxide (CO2) emissions. Diesel engines emit lower CO2 than gas engines, so the argument seemed a no-brainer. Diesel’s higher nitrogen oxide and particulate outputs escaped notice at the time, so manufacturers and governments began to promote diesel power for cities with great success. In Europe, for example, diesel-powered cars grew from a 10 percent market share in the mid-1990s to 55 percent by 2012.
International enthusiasm for diesel engines has reversed. Air-quality choked cities around the world including Paris, Bristol, Sao Paulo, and Brussels have declared “car-free” days. Tokyo banned ‘dirty’ diesels from its streets in 2000. At a Mayors Summit last week, BBC News reported that Paris, Athens, Madrid, and Mexico City said they are going to ban all diesel-powered cars and trucks from their cities by 2025.
“Our ambition is clear and we have started to roll it out: we want to ban diesel from our city, following the model of Tokyo, which has already done the same,” said Paris’ mayor Anne Hidalgo.
A campaign is on in London for its mayor to commit to a similar plan, but some want the ban to extend further. Alan Andrews, attorney for ClientEarth said, “In the U.K., London’s mayor is considering bolder action than his predecessor, proposing an expansion to the planned Ultra-Low Emission Zone. This is welcome but we want him to go further and faster. And it’s not just London that has this problem, we need a national network of clean air zones so that the problem is not simply pushed elsewhere.”
Perhaps by the middle of the next decade, most people who bought small diesel-powered city cars at government urging in the 1990s and 2000s will be driving electric vehicles or using shared mobility services in conjunction with mass transit and no longer even own private cars. But think of the people who end up stuck with cars they bought years before, thinking they were doing the right thing, not unlike the emphysema and lung cancer patients who remembered doctors in ads assuring them that “LSMFT — Lucky Strikes Means Fine Tobacco” because the brand was less irritating to the throat.
