“We will meet the emission standards of gasoline engines, with SCR,” said Wolfgang Hoffmann, Audi of America’s director of product planning. Hoffman spoke to a panel of diesel experts from the University of Michigan ’s Automotive Research Center, Shell Oil Company, CSM Worldwide, and DaimlerChrysler during the Detroit auto show in January. “You make the investment and use the technology developed in the U.S. and introduce it in Europe . You can’t lose money, you have to make money to invest in future products. We will base our decision on that, and our decision hasn’t been made for the U.S. ”

Audi is working on more than just diesel technology, said Hoffmann. “Audi is part of a bigger group, looking at various options, at the moment we are in the state of going away from traditional gas cars into alternatives. I don’t know which road we will go with, but we have to go with more than one. You don’t know which horse is going to win this race.”

Hoffmann explained some history of the company: “In 1999 we introduced an eight-cylinder common rail TDI, to show it’s also something for the rich, the famous, and the executives. It had 354 lb ft of torque. Today we’ve got a 4.2-liter producing 479 lb ft. At the same time it achieves 25 mpg. That’s more torque than a Corvette Z06, which is a monster. It is hip to drive a diesel. You’re in the ‘In’ crowd.”

Hoffmann recently transferred to North America from Germany , where he was a diesel fan. “Why do we Europeans love it? You can expect 25 percent better fuel economy. In Michigan you have a 50 mph speed limit in town. I have to accelerate quickly if a big truck is coming. Acceleration could be in some instances life-saving. This feeling of power with a diesel is just a tip of your foot away.”

“An issue for the Europeans is biodiesel. We’re not so dependent upon non-renewable fuel. Our diesels are capable of B10,” he said. However, he is sensitive to tax incentives that favor diesel in Europe , and biodiesel in the U.S. “At the end of the day the technology you end up with is down to the customer. The tax incentive may be a little short-sighted.”

“If you asked me 20 years ago, I would say the diesel is for people who are looking to save a little money. Now customers are in a diesel and you can’t get them out of it. Ten years make a hell of a difference. Diesel penetration was only 15 percent in Europe then.”

The economics of diesel cars’ longevity is something Hoffmann favors: “I believe that a diesel will have higher residual value. Diesels are $2000 more expensive, but you could recoup $1500 within three years. That’s the peace of mind that the customer can have. In the luxury segment the diesel makes more sense. We have stories of taxis in Germany with one million miles on the car.”

forecast spotlight: Bosch              

At the recent Society of Automotive Engineers show in Detroit , Diesel Forecast asked John Moulton, president of diesel systems for Bosch, where he saw the most work among the automakers to meet 2009 and 2010 emissions rules. “Most of them are going with SCR technology, though most have stated that in public. That’s the primary path, to get that system through EPA.”

Bosch develops mainly engine management systems, and supplies all of the Big 3 automakers in the U.S. , as well as overseas manufacturers such as VW and BMW. “There’s still a competition between the NOx storage catalyst and the urea injection systems. Choosing which is up to the OEMs--we’re not in the aftertreatment business. Our position is you’re going to need some level of aftertreatment for NOx clearly, either a filter, or some level of NOx aftertreatment, and the key is if you can get the engine-out exhaust minimized, you can minimize the cost of the aftertreatment.”

The prospect of homogeneous charge compression ignition is a direction Bosch is pursuing vigorously, said Moulton. “I’m real excited about HCCI, it’s really a competition. One of the biggest competitors to diesel in Europe is the HCCI gasoline engine. Competition is good and it’s driving technology. Eventually if we go to HCCI, that NOx requirement gets reduced further and further. It’s not that easy, if you solve the NOx problem, it creates a hydrocarbon and carbon monoxide problem. It’s really a balancing of the technology. We’re still learning a lot. I guess the message from me is there is still huge potential to improve emissions. HCCI is still a little bit further out, in the meantime we’re going with SCR technology.”

Combustion management has become a well-defined science, according to Moulton, and although there are six- and seven-hole injectors with carefully tapered holes, he says that going to more complex systems, such as nine-hole and greater injectors is not likely. “You get to a point of diminishing returns. Just like the pressures we’re running now. The question is how much do you really need. Higher pressure is higher cost. We’ll see how that ends up. We provide control systems and the closed loop controls. For aftertreatment to work you really have to have a closed loop control.”

Bosch does its own development on customers engines, to learn what the engines are capable of and to try out the companies’ existing knowledge. “We are looking at how to optimize combustion so that we are a competent partner to the OEMs. We work with OEMs, so we’re in a unique position to know pretty much what everybody is working on. But we have to be in a position of where we can do our own combustion work. We understand how to apply our technology to the engine, and we can’t wait for the OEMs to come to us with their engines. We’re going to them and showing them what they can do with their combustion. I would say we have joint development projects with the OEMs, pretty much everyone puts all their know-how into the bucket and works toward a solution. We’ve worked with all the major OEMs and have a tradition of not leaking one’s work to another. That’s how we can sell outselves. Particularly in diesel, we’re the leader in that technology.”

Moulton says that Bosch has no problem keeping knowledge gained from one automaker separate from another, to keep competition alive. “In general, we put separate teams together; one team works with company X and one with company Y. That way the know-how stays in-house, but there is basic know-how that we provide to all OEMs. Some of the OEMs actually work closer together than you realize, particulatly in the U.S. An example is the Ford-GM six-speed transmission, we developed the control technology on that. Where they can find a win-win situation, they can do that. We’re not in the business of getting OEMs to work together, that’s something they have to orchestrate themselves.

Moulton believes the current Ultra Low Sulfur Diesel fuel that is expected by the fall of 2007 is sufficient to enable further engine development for lower emissions. “Clearly new technology requires a high quality diesel fuel, with good lubricity, no sulfur, and we’re working to hone in on what types of fuels will be successful. We’re able to work with what’s available, we know what we have and we know what we need to do to get it to work.”