Audi's EV Dakar Rally Car Is Resurrecting the Range Extender

To compete in the punishing desert race, the auto company has turned to discarded hybrid tech. It could change how electric cars are made.
Red and black Audi EV vehicle driving on red desert sand dunes in Dakar Morocco
Photograph: Michael Kunkel/Audi Communications Motorsport

Audi’s intentions to compete in the world’s toughest rally using an electric car started 15 months ago with a white sheet of paper. The company shuttered its former rally division back in the late 1980s, and by its own admission, thanks to staff attrition, has lost nearly all of the knowledge acquired during a period when Audi won the World Rally Championship both in 1982 and 1984. 

The Dakar rally is a punishing off-road endurance event of ridiculous proportions. Distances of each stage can run up to 900 kilometers (560 miles) per day. The terrain traversed is much tougher than seen in conventional rallying, so the vehicles have to be built specifically for the task—mere modified on-road vehicles won’t cut it. 

The race originated in December 1977, following an incident where Thierry Sabine got lost in the Ténéré desert while competing in the 1975 "Cote-Cote" Abidjan-Nice rally. During this unintended diversion, he decided that the desert would make a good location for a regular competition. Some 182 vehicles took the start of the inaugural rally in Paris. Only 74 made it through the 10,000 km (6,200 mile) course crossing the Sahara to the Senegalese capital of Dakar.

Photograph: Michael Kunkel/Audi Communications Motorsport

As a result of the pandemic, with no possibility to fully test any equipment in race conditions, Audi’s target this first year back in rally sport was merely to finish the Dakar. However, halfway through the event, all three cars are still in the running, and the team has even picked up a win in the 636 km third stage with rally veteran Carlos Sainz driving, at the age of 59. “The biggest surprise is everything is running,” a team spokesperson tells WIRED.

At first sight, Audi’s 2022 Dakar contender doesn’t have much in common with your average family car. The RS Q e-tron is a giant Tonka Toy, 4.5 meters long and two meters tall. Beneath the Darth Vader bodywork is a tubular frame, braced with carbon panels and housing a battery, three electric motors, and a petrol engine. It’s safe to assume nothing like it will ever drive down a street near you.

So why is Audi doing this? It’s partly the prestige of the Dakar, of course: Since its beginnings, this event has been a byword for adventure and the romance of the desert. After originally running from Paris to Dakar, the event moved to South America in 2008 following a terrorist attack in North Africa. Despite being geographically displaced, the name remained, and in 2019 the Dakar moved again, this time to Saudi Arabia, in a bid to conjure back the event’s desert origins. Winning the Dakar is still prestigious, and 2022 is Audi’s first attempt.

Photograph: Mikel Prieto/Audi Communications Motorsport

But alongside this, Audi is determined to become a premium electric brand and it wants to win the Dakar with battery power. That is extremely challenging, given that competitors must complete up to 600 miles a day, driving through some of the most remote and inhospitable landscapes on Earth. They barely see a camel, never mind an EV charger.

But what Audi sees is an opportunity—a chance to experiment with an old idea that’s making a comeback: the range extender. This is a battery-driven electric car that also has a petrol engine onboard, acting as a power supply. The engine never drives the wheels, it just keeps the batteries juiced up as you drive along. Ten years ago, range extenders were “the future”: Vauxhall (Buick in the US) and BMW both offered them, while Audi developed a concept car.

But then the world changed—Tesla came along, battery technology improved, and suddenly range extenders were outmoded. This makes Audi’s 2022 Dakar entry something of an outlier, because it is the mother of all range extenders.

First, the engineers “borrowed” the electric motors developed for Audi’s Formula E race car—one motor drives the RS Q e-tron’s front axle, one the back. Then they modified a light, four-cylinder engine, formerly used in an Audi DTM racer (DTM is Germany’s premier league for touring cars). This exotic engine is connected to a third Formula E motor, which is used as a generator. In other words, the petrol engine spins the motor and electricity comes out the other end. So when the RS Q’s battery is depleted, 300 miles from anywhere, the engine automatically starts up and holds the revs at a fixed point to recharge it. Running at a constant, fixed rpm means the engine can be tuned to be extremely fuel efficient. How efficient? The RS Q has a 300-liter petrol tank, while most Dakar cars carry 600 liters.

The performance is equally impressive. The RS Q can accelerate from a standing start to 62 mph in 4.5 seconds… on sand. Such is the efficiency of the rally car's regenerative braking that at the ends off stages Audi's engineers are finding that the brake discs, usually completely black from dust off the pads as a result of the gruelling treatment meted out by drivers, are practically clean.

The car’s power system was particularly put to the test on day two of the rally, after Sainz got lost. At the end of the stage, the fuel tank was completely empty, yet the car managed to complete the last 45 km at race speeds on battery alone. “It works,” says Stefan Moser, Audi Motorsports communications lead. “We don’t want to test it like this again, but it works.”

If the RS Q does herald a second chance for range extenders, what’s changed since 2012? It’s partly that electric motors, petrol engines and batteries have all got more efficient over the last decade; but it’s also a creeping realism about what a sudden, global switch to battery vehicles might mean.

The British government, for example, has committed to phasing out new petrol and diesel cars by 2030 and banning hybrid sales by 2035. The need to be “fully zero emission at the tailpipe” means the RS Q wouldn’t qualify, even if you did find one in a showroom (which you won’t). But Ofgem recently admitted that by 2050, electric cars and vans could push the UK’s electricity demand up by between 65 and 100 terawatt-hours per year—the equivalent of up to 10 new nuclear power stations. The whole of Europe faces a similar challenge.

“We all know if we changed every car to electric right now, we would have no lights,” says Sven Quandt. Quandt is the founder of Q Motorsport, Audi’s Dakar team partner, and his pragmatism sees real potential in the RS Q experiment: “We have to find alternative sources, alternative ways to run cars,” he says. “What we do now is only for racing, but if we could take this technology and transform it for road-going cars, you can have CO2 which is super low, because you only run the engine on defined revs, making it 100 percent efficient.”

The second big challenge for electric vehicles is the rising price—and environmental cost—of lithium batteries. Current EV batteries are around 100 kWh, but in the pursuit of an ever-bigger range, both Tesla and GM are talking about 200 kWh. In contrast, the RS Q e-tron’s battery is only 50 kWh, because range is no longer an issue.

“If I use a smaller battery, perhaps down from 200 kWh to just 30 or 40 kWh, I don’t use so many resources,” Quandt says. “This is important. Smaller batteries mean there are not so many environmental issues.”

Further proof of how seriously Audi is looking at this technology comes from Stefan Dreyer, head of development at Audi Sport. He states that Audi’s road car division has been involved in the Dakar project every step of the way. “Doing this concept, we’ve discussed everything with them,” he says, adding that the power supply doesn’t have to be an extravagant DTM engine. “You just need something to produce energy onboard,” he says. “So you could run the engine with a different [synthetic] fuel. You can change it to a gas turbine or to a fuel cell. In the end, it’s the whole system that we’re testing. It’s the concept that matters, the mindset.”

As we approach that 2030 deadline, and the pressure to convert the nation to battery power increases, it’s a mindset that may come to your street after all.


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