Audi was one of the first manufacturers to dive into the
hybrid pond, but these days it is much more interested in proselytizing about the benefits of Turbo Direct Injection diesels. Audi says TDI, which its engineers invented, is the cleanest, most efficient diesel in the world, and the company recently put its money where its mouth is by sending 180 members of the media along with a handful of Audi representatives to travel nearly 5,000 miles throughout the U.S. to demonstrate its real-world fuel economy. Of the four models that hit American highways -- A3, A4
crossover and the
Audi Q7 -- it is the Q7 that will first carry the banner of clean-diesel TDI into Audi's U.S. showrooms. By the time the demonstration ended the Q7 TDI had attained a 33.1 mpg figure, stunning for a full-size
SUV. At the LA Auto Show we got the chance to catch up with Wolfgang Hatz,
Volkswagen Group's head of powertrain, and asked him to explain the benefits of the new technology.