In 2008, NRDC was on the jury for the "Green Car of the Year Award". As noted in a recent New York Times op-ed, the award that year was given to - you guessed it - the model year 2009 VW Jetta diesel. With Sierra Club also on the panel, the award was heralded as the green seal of approval for new so-called "clean diesels".
However, for the record, NRDC did not vote for the Jetta diesel. The selection of the winner was not a consensus of the jury. While we were disappointed that our choice did not win, we recognized that there was a value to having more choices for high fuel economy vehicles in addition to hybrids and electric vehicles.
Of course at that time, we had no reason to suspect the massive fraud that VW was about to perpetrate on the American consumer.
Our decision to not vote for the diesel Jetta, or any diesel car in the future years (we resigned from the jury in 2013), is due to our concerns that diesel cars are inherently more risky.
That's because the inherent properties of diesel engine - it runs at a higher pressure and temperature than gasoline engines -means there will be more soot and NOx coming directly out of the engine than a gasoline car that meets the same standard. Consequently if a diesel car's pollution control system is bypassed or fails, the public health consequences are even greater than for a gasoline car.
As I wrote in my last blog, I and others at NRDC have spent decades on cleaning up diesel cars, trucks and buses. We ran a successful bus campaign in New York City and other cities during the 1990's called "Dump Dirty Diesels". In 1998, I testified to convince the California Air Resources Board to reject the auto industry's proposal to continue the pollution loophole for diesel cars. The diesel industry appeared to be responding by eventually meeting our standards.
So when the 2009 Jetta diesel was introduced, while we did not embrace it, we did not object to it. As I said on my recent NPR interview, I told colleagues and acquaintances we had no objections to diesel cars if they meet our standards.
At this point, I am not aware of any evidence that other diesel manufacturers are cheating. Those, like BMW and Mercedes which are using the more sophisticated "SCR" catalyst technology, should have no need for a VW-style "defeat device" computer program. Nevertheless, we understand that regulators are re-testing these vehicles on a tougher, secret test.
The VW diesel scandal has taught us many hard lessons. Perhaps the most important one is that to eliminate the inherent pollution liability of internal combustion engine vehicles burden, we must move faster to electrics and fuel cell cars without tailpipes.