Curtain for a new chapter: January 1-14, 2022, the new Audi RS Q e-tron will contest its first Dakar Rally. This marked the beginning of a new era for Audi in marathon racing.
It is the mother of all desert agglomerations: Dakar. Now also looking for a challenge, Audi will launch the Audi QS e-tron in Saudi Arabia in 2022.
“Never before at Audi Sport have we launched such a complex car in such a short time,” says Julius Seebach, Managing Director of Audi Sport GmbH and responsible for Audi Motorsport. “Our first endurance test under competitive conditions is now the longest and most sought-after rally in the world.” In the twelve stages of the Desert Rally in Saudi Arabia, the Ingolstadt-based company will meet another 91 entrants in the car class.
Audi highlight: The off-road all-wheel drive system is powered by two electric motors with a total power of 680 hp. I’m sorry what with the wattage phased up to 800 km across the desert? Without a charging station and limited range of batteries?
Photo: BiG Media
So it is no wonder that all the electronic car projects so far have failed in the marches of the Queen of the Desert. Audi now wants to change that — and use the Dakar Rally as a truly desolate test lab for its production vehicles.
There are twelve phases in the program. The total length of the rally is 8,099 km, which is a total of 4,252 km of timed off-road tests. The starting and ending point is Jeddah, and on January 8th is the Dakar rest day in Riyadh.
Matthias Ekström (43, two-time DTM Audi champion, one-time rallycross world champion), Carlos Sainz (59, three-time Dakar winner) and record Dakar winner Stephan Peterhansel (55, 14 wins) at the start.
Ekström on SPORT BILD: “One of the coolest cars I’ve ever driven.” Carlos Sainz adds: “At first, the only unusual thing was the combustion engine, which always runs behind me, even when I’m not on gas. You have to get used to that first.”
Engine: Hybrid (electric motor, battery charged by turbo motor)
Turbo engine displacement: 2000 cm3
Maximum system output: 500 kW (680 hp)
Driving: electric four-wheel drive
L/B/H 4500/2300/1950 mm
Empty weight: 2000 kg
0-100 km/h: less than 4.5 seconds
Maximum speed: 170 km/h
Gasoline consumption: 200g/kWh
Battery: Li-ion, 52 kWh, 370 kg
Tires: BF Goodrich front/rear 37×12.5R17g
Tank capacity: 295 liters max
We explain the complex technology of the Audi RS Q e-tron:
The heart of the RS Q e-tron is a hybrid system with a maximum output of 680 hp (500 kW). Both the front and rear axles are powered by a 250 kW (340 hp) Formula E electric motor. There is also an internal combustion engine behind the driver. This, in turn, turns on the alternator that charges the battery for the drivetrains.
The combustion engine is the 2-liter four-cylinder turbo engine that Audi used in the DTM until the end of 2020. Audi still has 30 of these units. The engine was revised for use in the Dakar. Stefan Dreyer, Head of Development at Audi Sport: “We have reduced production from 450 to 200 kW. It works at its best improved point in a narrow speed range between 4500 and 6000 rather than the 9000 rounds. “And it is very effective: its specific consumption is well below 200 grams per kilowatt-hour.
“The car is the most complex I’ve ever seen,” says Sven Quandt, founder of Audi Q Motorsport. He even compared the project to the first moon landing: “At that time, the engineers did not know what to expect. It is similar to ours. Termination on first use would be successful. “
lithium ion battery
Photo: BiG Media
The high-voltage battery is located in the middle of the Audi RS Q e-tron. Capacity (52 kWh) and weight (370 kg) are reminiscent of Formula E (54 kWh / 385 kg). Compared to the electric formula, the Dakar Rally is completely different: daily stages of hundreds of kilometers, tremendous resistance to driving in the soft desert sand, as well as high external temperatures and the minimum car weight set by regulations – these are extreme values in motorsport.
When rally drivers leave the Bivouac with a charged battery on the morning of each stage of electric driving, a very complex control process begins. Engineers have programmed algorithms so that power consumption and battery recharging are always in equilibrium at specified distances.
Example: If a difficult passage through a dune requires maximum power for a short time, then the charge level drops. Reason: According to the regulations, the engine power of the front and rear axle generator units is limited to a maximum of 288 kW. However, the transducer can provide a maximum charging power of 220 kW. In extreme cases, consumption is temporarily higher than power generation. “Something like this is possible for a limited time,” says battery engineer Lukas Folie. “But at a longer distance, there is always a zero-sum game. The absolute amount of power available on board must be sufficient to handle the day’s stage.”
For maximum efficiency, the RS Q e-tron recovers energy on its journey through the desert. MGUs on the front and rear axles can convert the rotational motion of the wheels into electrical energy. The result: although it has to move more mass due to regulations, the RS Q e-tron therefore uses less power than the competition.
Photo: BiG Media
“Audi has never participated in the Dakar Rally. So the first thing we asked ourselves was: How do we get the heat out of the car?” explains Sebastien Fruber, the engineer in charge of the cooling systems. Rather than aerodynamic efficiency, the desert model is all about the best possible heat dissipation. This is ensured by several cooling circuits.
Low-temperature high-voltage battery (HVB) circuit: Audi uses a coolant called Novec, which does not conduct electric currents, to cool the battery. This low temperature circuit contains coolant under the front hood.
Low Temperature Circuit of Engine Generator Units (MGU): The combustion engine is mechanically coupled to the MGU which generates electricity for the high voltage battery. It transfers its energy to two other units of electric generators: one driving the rear wheels and the other driving the front wheels. The three MGUs are connected to each other via their own low temperature circuit. Its heat is emitted through the left radiator in the front of the car. The challenge compared to classic cooling systems: “Desert air at 40°C cools the warm coolant by 60° only negligibly due to the slight difference in temperatures,” explains Fruber.
Two high-temperature coolant and charge air circuits: the drive system of the Audi RS Q e-tron also includes a transducer. The highly efficient turbocharged gasoline engine, which is arranged transversely behind the front passenger seat, has a fluid circuit with coolant. The engine oil circuit is thermally connected to this system via a heat exchanger. Exhaust gas turbocharging requires a second cooling system: compressed intake air flows through the charge air intercooler to the engine. The liquid coolant and the charge air cooler are located next to each other above the rear axle. The scoop on the roof splits the air flow between both radiators. “On difficult trails, for example when crossing dunes at a slow speed, this airflow may not be sufficient,” says engineer Fruber. “For this reason, there is a fan behind each of the radiators, which can extract warm air if necessary.”
Well chilled, will start in the desert from January 1st. We will know by January 14 whether the highly sophisticated technology will hold up.