A winning formula

This weekend, the 12 teams set to contest the 2021 FIA Formula E season will take to Circuit Ricardo Tormo in Valencia, Spain, for their first and only group practice session before the new season gets underway in January 2021.

What’s significantly different about this coming season is that Formula E has essentially come of age. The FIA (International Automobile Federation) which governs international motorsport, has now recognised the formula as an official world championship and this essentially raises the stakes considerably. For the competing teams and manufacturers it adds markedly to the series’ prestige and standing on the world stage and will see an already highly competitive formula got to the next level.

For Audi, a brand that has built its reputation in motorsport since the very beginning, the importance of Formula E both both for the competition and as a development tool is immeasurable. The increasing importance of all-electric vehicles makes the Formula E series as import today as the World Rally Championship was for the development of quattro or the 24 Hours of Le Mans for the development of everything from high-powered headlights to ground-breaking drivetrains. All of these technologies, developed in the cauldron of motorsport have, ultimately, found their way into the brand’s road-going cars. 

Significantly, as well as being a sanctioned world championship, this 2021 season will also see Audi using its own powertrain in its electric race cars for the very first time since Formula E began. Up until this point, a powertrain jointly developed with the brand’s technology partner Schaeffler has been the go to unit, but the new Audi e-tron FE07 race car will now be powered by a new inverter, developed by Audi Sport from scratch.

“Racing has always been at the very heart of what we do,” says Team Principal Allan McNish, himself a three-time Le Mans winner whose extraordinary motorsport career gives him a unique insight few can match.

“We have raced on whatever surface it may be, pushed to the absolute maximum as people and with the technology, and ultimately that filters through and [is used] on the cars that we drive on the road everyday.” 

The sheer pace of the Formula E series’ development in just six years has been much more rapid than anyone would have expected says McNish, but for Audi Sport he feels it is a perfect fit for the brand and its evolution.

With Formula E he says: “we’re able to demonstrate and develop our technologies, but we’re also able to do it with a message … not just as people but as a company.”

The flow down of technology from motorsport to Audi’s road vehicles has long been a mainstay of development, and Formula E is no different.

McNish cites systems such as ‘brake by wire’ which was developed on the race track, but is now employed in the Audi e-tron, the first battery-electric vehicle to use brake by wire as standard.

The in-house development of the all-new electric powertrain then marks another motorsdport milestone for Audi, and in the fledgling series one that is hoped will not only aid Audi Sport ABT Schaeffler in the coming competition but also help in the development of the brand’s road-going electric vehicles.

Certainly the new unit, designated the Audi MGU05, is impressive in design and execution, but it is also symbolic in the brand’s commitment to the electric formula, says Stefan Aicher, Head of Development e-Drive at Audi Sport. 

The need to develop engines and components was just as important in Formal E as it had been in the Le Mans series, says Aicher. If the brand wanted to remain competitive in the future, it was vital that it develop its own electrical drive – just as had been the case in other racing series in the past.

“We decided we wanted to do everything ourselves,” says Aicher, “the MGU, the inverter, the software and the build of the whole system.”

Two years later, the result is an electric one-speed drivetrain with an internal rotor concept, external magnets and a highly efficient cooling system. The MGU05 is made up of lightweight materials that come in at under 35kg – significantly lighter than the unit it replaces.

Not only is it lighter but far more efficient, which is of course the name of the game in all-electric racing. Exhaustive testing and stressing of the unit to its absolute limits have resulted in outstanding results, says Tristan Summerscale, Formula E Project Leader at Audi Sport. 

“We have achieved an overall efficiency of more than 95 percent for our powertrain. The new MGU inverter unit has an efficiency of even more than 97 percent in all relevant driving conditions.”

Put this up against a combustion engine of similar power output and the result is more impressive still. 

“If you compare our MGU with an internal combustion engine delivering a comparable power output of 250kW, our efficiency is not only twice as high, but our weight of less than 35 kilograms is also much lighter,” says Summerscale. “This clearly shows what an efficient solution an electric powertrain is.” 

In the Audi e-tron FE07 this equates to a blinding 0 to 100km/h time of 2.8 seconds and that efficiency will be a decisive factor when the new season gets underway.

But of course it’s not just about straight-line speed in Formula E:

“You want to go as fast as you can from the start of the race to the end of the race,” says McNish, “but if you did that with just wide open throttle, then you wouldn’t be able to achieve it.”

In Formula E, strategy is as important if not more so than in other motorsport disciplines. When to accelerate. When to lift off to achieve power regeneration and when to brake – likewise to recover power as well as to slow down.

The differences in the mindset between driving an electric race car are subtle, but real, says Lucas di Grassi, the most successful driver in Formula E.

“The technique you use to drive a fast combustion car and a fast electric car is essentially the same,” says di Grassi.

“Of course there will be adaptations like saving or conserving energy … and there are two things that are very important. Firstly the instant torque – as soon as you go on the power there is zero lag. With electric, as soon as you touch the throttle the car instantly accelerates.”

The second thing he says is the engine braking, where the traditional changing down through the gears for the corners is handled completely differently with an electric race car that uses engine braking to harness energy for later use.

“We only have one gear, but you can program in a far more effective way for the engine to brake the car … so you have more options,” he says.

“The other thing is that you don’t have the sound, so you can hear what the car is doing in a much more precise way also.”

The similarities and differences with conventional racing are endless, but the speed with which developments in this all-electric format will impact road cars in the future is significant says McNish.

While the hardware for the new race cars is now set and homologated for up to two years, the software is an area that will yield dividends and change throughout the season.

“Where we’re finding a lot of performance is in our software, and I do believe that’s going to be a major factor for us and also for the road cars.” Says McNish.

“There’s a limit to what we can do with the hardware [in this season of racing]… but we’ll be bringing a new software update to every single race.”

The coming FIA Formula E season will be one to watch, as much for the promise of more close and intense racing as for the developments in the cars themselves. This racing formula will, in an ever decreasing timeframe, define and develop the technologies that find their way into the Audi you drive tomorrow.