Meeting minimum requirements is hardly green. That’s why there are emission ratings.

Those diesels only deliver T2B5, very dirty by non-hybrid gas vehicle standards and certainly nothing to be proud of.

SULEV is where the true rating level of clean begins… which has proven cost prohibitive for diesel systems so far.

I hope diesel finds a place in America’s green portfolio, if only for the selfish reasons listed above.

In California, diesel cars must meet the same emissions regulations as gas cars. That is why diesels have not been available here for the last few years. The urea technology was developed to get to these standards.

It is true the smaller engines – 2 liters and under – have been able to meet these standards without the urea. The Volks TDI does not use it. Neither will the upcoming Honda diesel Accord.

In SoCal today diesel is actually cheaper than 87 octane unleaded again. As we speak, unleaded is $2.17 and diesel $2.11 at the station right across the street.

Diesel particulates from heavy equipment, trucks, tugboats and ocean going ships are an environmental disaster in SoCal. I have worked very hard on this issue, and know a bit about it. These cars, however, are much, much, better. And you are right, they do make a lot less CO2.

It’s a wonder how Europe has survived for so long with these terrible diesels making up 50% of their automotive fleet. Come on guys, is now really the time to start rejecting such proven technology on the basis of yesterday’s stereotypes? If auto makers can produce Li-Ion electric cars I bet they can come up with some pretty refined, environmentally-friendly diesels. Just my $0.02.

On a separate subject: Hydrogen is a non-starter. The cost and emissions required to make, distribute, and store the stuff exceeds nearly all of the alternatives!