Rentech's synthetic RenDiesel, a biodegradable fuel made by gassifying biomass, presented no problems for the pair of Audi A3 TDI's that participated in Green Car Journal's 1,000-mile long 2010 Green Car of the Year Tour. In fact, it's safe to say that the diesel-fed Audi's sipped the RenDiesel without flaw.
How did they do mileage-wise? Driving the length of California, one RenDiesel-fueled A3 managed 39.7 miles per gallon and the other hit 43 mpg during the tour, numbers which line up with A3s running on a more conventional diesel diet. During the drive, the A3s were fed nothing but RenDiesel, proving that advanced synthetic fuels, which promise to reduce lifecycle greenhouse gas emissions by as much as 97 percent compared to crude-based conventional diesel, are a viable solution and easily used in today's crop of clean diesel models.