World governments are spurring carmakers to lower emissions through stricter regulations, that much we know.

But how much effort is there to make the cars lawmakers actually use on the job cleaner?

One carmaker sees the importance of that question--or at least a good marketing opportunity.

Audi now has a new customer for its TDI diesel luxury cars: the German Federal Parliament.

The German legislature will take delivery of 66 Audi A6 2.0 TDI Ultra models in the coming weeks. They'll be used by members of the Parliament for "official trips," Audi says.

2014 Audi A6 2.0 TDI Ultra

2014 Audi A6 2.0 TDI Ultra

This version of the A6 TDI has a 2.0-liter turbodiesel four-cylinder engine that produces 190 horsepower and 295 pound-feet of torque. It will be mated to an S-tronic seven-speed dual-clutch transmission in the cars used by Parliamentarians.

In comparison, the U.S.-spec 2014 Audi A6 TDI (along with four other Audi diesel models) uses a larger 3.0-liter V-6, rated at 240 hp and 428 lb-ft. An eight-speed Tiptronic automatic transmission is the sole option on this side of the Atlantic.

The "Ultra" designation further differentiates the A6 TDI sedans that will enter service with the German Federal Parliament. These models retain a high level of equipment while still emphasizing efficiency, and aren't currently offered in the U.S.

Audi says the A6 2.0 TDI Ultra achieves the equivalent of 53.5 mpg on the European testing cycle, though its ratings are often as much as 25 percent higher than U.S. EPA ratings for the same car. The EPA rates the 2014 A6 3.0 TDI sold in the U.S. at 29 mpg combined.

While you'll never see members of the U.S. Congress in German luxury sedans, Audi has pushed diesels hard in the U.S., claiming they mark the way to a more-efficient future for the segment.

However, Audi will also reportedly add plug-in hybrid versions of the next A6, A7, and A8 sedans, as well as the Q7 SUV.

It's nice to have options, after all. Especially for politicians.


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