Audi Again Leads the Way:

Three years ago, Audi paved the way toward the future for auto racing by announcing it would develop a diesel-powered car to continue its remarkable winning pedigree in one of the world's most prestigious events, the 24 Hours of Le Mans.

Now comes news that Audi will compete at the French endurance classic June 14/15 with the "next generation" of biofuel, manufactured from biowaste and promising a massive reduction in the emission of carbon-dioxide when compared with traditional diesel fuel.

Audi's ground-breaking turbocharged V-12 diesel-powered R10 TDI was unveiled in December 2005. It promptly trounced all-comers first time out at the 12 Hours of Sebring, then repeated the feat at Le Mans.

It certainly wasn't the first time a diesel-engined car had been raced, not by a long way, but it was the first time a major automobile manufacturer had made a real commitment to developing an alternative to gasoline as the primary power source.

The potential for diesel engines in racing has long been recognized. Such motors tended to provide a broad power band and relatively good fuel economy, but their efficiency came at a price - notably additional weight and the necessary expense of developing an entirely new transmission capable of delivering the diesels' markedly different power characteristics to the road effectively and reliably.

Audi took advantage of a new rules package developed by the Le Mans organizers, the Automobile Club de l'Ouest, which was intended to encourage the introduction of "greener" technology. The rule-makers and the R10 TDIs effectively obsoleted conventional gasoline-engined cars, which were instantly rendered uncompetitive. Audi completely dominated the 2006 Le Mans race, although, happily, the German giant's breakthrough provided the impetus for another European manufacturer, Peugeot, to develop its own turbo-diesel. The French company's gorgeous, coupe-styled 908 HDi FAP proved fast on its debut in 2007, snaring the pole, but unsurprisingly didn't possess the necessary reliability to challenge Audi for the victory.

We will see in two weeks' time if one more year's development has turned the tables. Peugeot was undefeated in the 2007 Le Mans Series (a program of five races run to ACO rules), albeit with little serious competition, and made an impressive bid to win this year's 12 Hours of Sebring in March. It was ultimately unsuccessful - indeed all the diesel cars hit mechanical trouble, handing the victory to one of the lightweight LMP2-class Porsche RS Spyders - but Peugeot will return to the Circuit de la Sarthe with a top-quality driver lineup (including 1995 Indianapolis 500 winner and 1997 Formula 1 World Champion Jacques Villeneuve) and a fresh optimism.

Audi, meanwhile, has not been resting on its laurels. Aside from mounting a challenge to Peugeot's domination of the LMS for 2008, it has worked hand in hand with development partner Shell to produce a new, more environmentally friendly fuel.

Until now, the R10 TDI has utilized a synthetic Shell V-Power Diesel race fuel created from Natural Gas in a process called Gas To Liquids (GTL). Fuels with these components are already available at the pumps for street cars. For Le Mans, a small amount of "next generation biofuel" has been mixed for the first time with the previously well-proven GTL components. BTL (Biomass To Liquids), as it is officially called, is extracted from biowaste that is unfit for use in foodstuffs, for example from waste wood. BTL promises a reduction in the amount of CO2 emission by almost 90 percent compared to traditional diesel.

Although they are manufactured from different raw materials, the two alternative fuels, BTL and GTL, are practically sulphur-free and odorless. They combine quality and efficient combustion with reduced exhaust emissions.

The new fuel made its public debut Sunday, June 1 at the official test day at Le Mans which traditionally provides teams with their only opportunity to test on the 8.5-mile circuit prior to the race.

The introduction of this new fuel source by Shell and Audi is to be commended. Neither company has yet divulged the true extent of what is acknowledged as a "small percentage" of the new-generation fuel, but regardless it represents another step forward for auto racing in general.