As a result, motorsport is starting to attract unwanted attention and criticism for what many view as a waste of resources in this environmentally sensitive time. So, to keep the target off its collective back, various racing series worldwide are putting forth huge efforts to devise some sort of conservation or alternative energy strategy. However, history is already littered with successful and unsuccessful attempts in this regard, so the recent resurgence is more a combination of good timing and better technology.

While most racing fans view Formula One as the ultimate technical challenge and the most advanced racing on the planet, the truth is that sports car racing has historically embraced the most diverse field of vehicles and technologies. Probably the most visible of those efforts today is the LMP1 class racing at the 24 Hours of Le Mans, and the various regional championships run to the same rules, including the North American-based American Le Mans Series.

Two challengers have become the most visible and successful alternative-fuelled racecars: the diesel-powered Audi R10 TDI and Peugeot 908 HDi. The R10 is the latest in a long string of Audi prototypes to dominate Le Mans and the ALMS, becoming the first ‘oil-burning’ vehicle to win the 24 Hour race, while the Peugeot’s runner-up finish at Le Circuit de la Sarthe in 2007 and its subsequent Le Mans Series championship title prove the French company’s challenger is just as fast.

The benefits, as exploited from the rulebook, play on a turbo-diesel’s inherent advantages: just as much horsepower as a gasoline-powered LMP1 car, with twice the torque. As an added bonus, the extra range that diesel fuel provides means less time spent in the pits for top-ups. Plus, with advanced particulate traps and aggressive muffling, the R10 and 908 are quieter and pollute less than their rivals.

However, just because the Audi and Peugeot are currently successful doesn’t mean they were the first. In fact, the first oil-burner at Le Mans was in 1949, the first race held after the Second World War. The Delettrez Diesel entered by brothers Jean and Jacques Delettrez ran a 4.4L 6-cylinder, but ran out of fuel halfway through the race. The team ran again in 1950, as did another diesel car, the mid-engined two-cylinder MAP, but neither finished. Delettrez’ final attempt in ’51 proved frustrating again as they recorded another DNF, this time after only four hours.

More recently, in 2004 the privateer Taurus Sports outfit ran an LMP1-class Lola with a diesel-powered Caterpillar V10 at Le Mans, and looked quite impressive before teething problems forced them to retire early.

Perhaps to reflect a more regional focus and North Americans’ big push towards ethanol, the ALMS moved to change its spec fuel to E10, a blend of 90 per cent gasoline and 10 per cent ethanol. That might seem a token gesture as the Nasamax team ran at Le Mans in a bio-ethanol-fuelled LMP1 in 2003 and ‘04, but the pressure has inspired the ACO to decide that the 2008 24 Hours race will see all cars running partial mixtures of bio-ethanol fuel… except the diesels, of course.

The other major technology push in sports car racing came in 1998 when Panoz put forward a gasoline-electric hybrid version of its Esperante GTR-1, dubbed the Q9, although the car failed to qualify for the event. However, there are now rumours that Acura is looking to incorporate a hybrid system to its yet-to-be-built LMP1 car to compete on a more even footing with the Audi and Peugeot teams.

Looking outward from the Le Mans-based series, diesels have made great showings in touring car racing as well with BMW winning the 1998 24 Hours of the Nurburgring in a 320d. Plus, Volkswagen’s Spanish sister SEAT have run a brace of Leon 2.0 TDI racecars in the World Touring Car Championship alongside two gasoline-powered versions, taking runner-up in the Manufacturers’ Championship in the process.

Indy car racing has been fairly stagnant in terms of technological revolutions over the last 30 years as most of the innovation has been regulated out in exchange for extremely strict rulesets or spec series. However, diesels ran with some success in the first half of the 20th century. The 1931 Cummins Diesel Special, a modified Duesenberg Model A chassis with a Cummins diesel engine, was driven by Dave Evans to a 13th place finish. It was also the first car to complete the 500 miles without a pitstop. In 1934, “Stuby” Stubblefield scored the highest-ever finish for a diesel at Indy with his 12th-place finish, while in 1952, Freddie Agabashian impressed everyone in his Kurtis roadster chassis with Cummins diesel power by taking pole position.

However, since the ‘50s, alcohol-based fuels have ruled in North American open-wheel racing; methanol was the brew of choice for decades before the Indy Racing League switched the spec fuel to full-bore ethanol in 2007.

The only other major initiative on the table for open-wheel racers is Formula One’s adoption of hybrid-electric powertrains for 2010, which should finally give Honda and Toyota a leg up compared to their rivals Ferrari, Mercedes-Benz and BMW.

In preparation, Toyota has been consistent in its use of racing as a hybrid engineering testbed. It first ran a Lexus GS450h in the 2006 Tokachi 24 Hour race, finishing 13th, and then won the event in ’07 using a modified hybrid Super GT Toyota Supra. A rally-prepared GS450h also ran successfully at the 2007 Targa Newfoundland, winning its class and scoring 18th overall out of 48 finishers.

(Those wondering what NASCAR is doing about alternative fuels will be pleased to know that the series has just started running unleaded fuel in 2007… don’t expect any major changes soon.)

So, for the most part, the future of alternative fuel racing is bright indeed. At the SEMA show in October, 2007, Volkswagen announced that is launching the Jetta TDI Cup, a spec series using diesel-powered cars that will appear at eight major racing venues during 2008. Also, the Jetta TDI Cup series will be certified as CarbonFree by Carbonfund.org.

It would be an easy argument to make that if the Audi R10 TDI had not been successful that the Jetta TDI Cup would never have seen the light of day. Just as the old saying goes, “Win on Sunday, sell on Monday.”

However,the racing community has legitimately embraced the reality of alternative-powered racecars and is trumpeting the idea that improving the breed on the track allows technology to funnel down to the vehicles we drive every day. Are these efforts simply giant corporations looking for that split-second advantage on the racetrack and wrapping themselves in the enviro-conscious rhetoric simply for good PR? Time will tell.