The money question (literally) is:

How much is this system going to add to the cost of a vehicle? Will it be competetive with hybrids, at least?

Technologies that can reduce NOx in the presence of O2 are indeed very complex and expensive. The first question therefore ought to be: does the US really need NOx emissions limits so low they can only be met with such technology? Health and air quality experts will surely argue that it absolutely does and, will brook no backtracking. However, consumers/voters should consider that there is also a significant price to be paid for *not* having lean burn engine options, at the pump as well as in Iraq.

NOx emissions limits are a political choice, not a commandment from a higher power. Have EPA and CARB gone too far too fast?

---

With ULSD becoming available later in the year, NOx store catalysts will be the first choice of many, provided the life expectancy problem can be solved. Frequent regeneration causes thermal cycling of the washcoat. Most of the plasma assist systems seek to reduce the energy required to achieve desorption and initiate reduction, both to increase life expectancy and to reduce the fuel penalty.

Arvin Meritor's system pretreats the fuel instead, to reduce NOx production during the combustion process. That is also the objective of flameless (HCCI) combustion research for both diesels and GDI, but it is inherently limited to part load operating points.

The most cumbersome solution is SCR, because it involves a new distribution infrastructure for the AdBlue additive plus enhanced OBD functions to ensure the vehicle cannot be operated normally without it. These hurdles have been overcome in Europe but not yet in the US. Moreover, AdBlue freezes at -11 deg C, so a heater is required in the additive tank. The whole system is quite effective at reducing NOx and will become more so once the fast NOx probes required for closed-loop control become available. However, its complexity and cost effectively restricts it to commercial vehicles and luxury sedans.

Tony -

the vast majority Americans have no experience of modern light duty diesels with turbos, common rail injection and particulate filters. Indeed, in Europe, diesels are now considered premium engine options! For the additional up-front expense, customers get 20-30% better fuel economy and substantially more low-end torque.

Simply not liking something you don't even know is called a prejudice. Think with your head please.

As for truck stops, you are correct. However, there is no law that prevents regular filling stations in the US from offering diesel. I read somewhere that some 40% already do (varies by state I suppose). That percentage would go up very quickly if diesels werre more widely available. Besides, the most obvious application for diesels in the US would be for heavy vehicles such as pick-up trucks and delivery vans. Owners of these types of vehicles might be more willing to accept a phasing-in of diesel fuel availability than others.

Besides, stratified spray-guided GDI engines would achieve similar fuel economy (based on fuel mass, not volume!) with widely available regular gasoline. Of course, they require the same type of expensive NOx aftertreatment that diesels do if they are to meet US emissions standards.

Tony, you're still a nut-case. Diesel is available at any major intersection where there are several gas stations. Available at all toll-road stations, and of course people with $60G cars stop at truck stops! You been to one lately??? They're insane: movie theaters, spas, food courts.

Every post you spew some nonsense on how the US doesn't want diesels, yet every sales metric that now comes out shows the opposite is true. You are a silly, silly person and are deserving of a light tap on the head to bring you back to reality. :)

The energy loss of this plasma system could be partially recouped by putting the plasma reactor ahead of a turbo. Since turbos get thier boost from thermal load, the increased temperature would help spool the turbo. Then put the Catalytic converter after the turbo.

NOx emission limits in europe are a lot higher,

NOx are a political choice

I agree, lower NoX emissions requirements are an impractical step in the US, they should have reqired lower sulfur in the fuel FIRST.

Chingy:

> Every post you spew some nonsense on how the US doesn't
> want diesels, yet every sales metric that now comes out
> shows the opposite is true.

OK; prove it. Sure, some Americans want Diesel engines; some people would want carburated cars if they were available. I can assure that at least in California, you will not find much support for making our air quality worse so that we can have these vehicles.

I also have recent experience with European Diesels, and I am not impressed. They aren't terrible cars, but they are loud (at least outside the cabin), they do smell, and I was absolutely amazed to see modern cars which puffed smoke on tip-in. I haven't seen this in over 20 years. Hybrids are a better option by far.

Rafael: you say car manufacturers would dump the ice in a heartbeat if they had a chance. Perhaps some of the newer startup companies we see popping up, but as for the big makers, I highly doubt it. There is waay too much invested and involved in their current setups to "dump" the ice like it's a hot stone. And there are many other "interests" in the current setup. Think of the millions that are employed by the current auto industry. There are millions and millions of relatively complex automobiles built by our citizens all over the world.

Then there is the multi-billion dollar parts industry. Their security (and also the whole service industry, broadly speaking) is ensured largely by the ice, or rather, how they all seem to breakdown so regularly after the warranty period ends (and sooner, esp with domestics). Lose the I.C.E. for, say, an EV, and half of North America is out of work! The powers that be would never allow that to happen. At least, it will take a lot of time and pressure: it won’t happen immediately. No big maker is going to drop the ice overnight. There are many changes that could have happened already that don't because of vested interests and politics, sadly. Maybe the climate is different somewhat in Europe.

"...I can assure that at least in California, you will not find much support for making our air quality worse so that we can have these vehicles...."

If diesels are so bad for air quality, then why does air quality (specifically smog) not only not improve in California, but is often WORSE on weekends when diesel truck traffic decreases by as much as 80%?

I would argue that reducing the number of GASOLINE vehicles on the roads (especially the older high-emitter) and replacing them with clean diesel cars would have a far greater impact on improving air quality since VOCs and CO control the "ozone production efficiency" of NOx. I agree with Raphael and a few other posters that there's certainly no hurry to reduce NOx emissions, like current regulations mandate.

Carl has it exactly right. We need to get prevent all of the older cars from being used as daily drivers. The states which have smoggy cities should long ago have declared that all older vehicles (say 10 years or older) as "antiques." These vehicles would be limited to approx. 3000 miles a year without a hefty (say $1/mile) penalty at re-registration for any extra miles. Exceptions might be made via a standard emissions test. As was said above, it is a political decision to limit affordable clean diesels. It should also be a political decision to reduce the greater harm eminating from older vehicles. Commercially registered trucks should be required to be retrofit with the latest after-treatment without a doubt, even at significant cost. They are the worst offenders, and are a bad example for the business comunity. These measures will do far more to affect our health than will prohibitively raising the cost beyond that of a Euro 5 diesel. The reg's must fit the ability of the public to reasonable afford the technology. When reasonable 50 state diesel reactor/catalysts comes along, they will be adopted.

What's in a name -

glad to see that you are keeping an open mind. Diesels have pros and cons, just as gasoline engines and hybrids do. There is no magic bullet here.

Historically, California has taken the lead in tightening emissions regulations, and for good reason: LA's unique combination of topography, wind direction and abundant sunshine is highly conducive to smog formation. Politicians in for other states have chosen to adopt CARB regulations lest they be accused of neglecting a public health issue. The EPA is to some extent in competition with CARB for the same reason. Regulators in many other countries believe US regs are the gold standard that they should aspire to.

The result is that the highly unusual situation of LA has strongly influenced emissions legislation all over the world, almost regardless of variations in regional climate. As long as gas was cheap, terrorism unrelated to oil and climate change just a hypothesis, this did not matter much. Now that the situation has changed, emissions regs and their impact on consumer choice et. al. ought to be a legitimate subject of debate. It's about hitting the right balance for the 21st century.

Chingy-

First, I don't see press releases (or transcriptions of press releases) as proof of anything. This is like asking the parent of a kindergartener which kid in the class is smartest.

Second, I think there is definitely better evidence of Diesel demand than this. 3000 units sold out of 6000 units shipped? That's not exactly a groundswell. Doubling their 2005 expectation by selling 10000 units? Their expectation was made before Katrina, etc., and was pretty low.

Third, this is not the best test case. The Liberty is a Diesel, but it does not use best-in-class technology. It is quite audible, does smoke, and isn't particularly powerful even for a Diesel. I was surprised when it came out that DC didn't at least use one of their own, much better Diesel engines.

I think that the VW Diesel article you linked to earlier is a better example. I don't doubt there are plenty of people who want a Diesel--the question is how many want to increase pollution to do it. As I said; there are plenty of people who would want a new carburated car burning leaded fuel if they were available. That doesn't mean we should start selling them again.