season five regulations offer an opportunity to move further up the grid?
Sylvain Filippi: It’s a huge opportunity. To be fair, us at Virgin Racing we joined at the very beginning. Now all the car manufacturers are coming in, and that’s fantastic news because that’s what we want. We want to stimulate development as fast as possible, and we want this technology to go to road cars as much as we love racing. We would not be here if it were just for the sake of it. If this technology just stayed on race cars, then there isn’t much point. The whole point is for this technology to go into road cars.
It’s good that we are with car manufacturers and pretty much all the teams are doing something. In terms of opportunity, it’s huge because it’s a brand new car. At the moment, everything we’re doing is an evolution now of what we’ve been doing before. So, teams who did a good job, you tend to improve rather than start again, but season five we all start from scratch.
The roadmap is extremely challenging because the battery is almost twice as big (54kwh compared 28kwh), but we have to do the same race distance, and we have to do it with more power. Normally out of this triangle of criteria, one has to give, but somehow we have to. So the challenge is to develop a more powerful powertrain but much lighter than what we’re doing at the moment. The battery will be a little bit heavier because it has so much more capacity, so it’s an extremely challenging engineering design.
We will all start from scratch. The only thing that will not change radically is the architecture of the car so that the battery will be in roughly in the same place.
RW: What is the biggest challenge in terms of developing this new technology? Is it weight, power output, heat management, etc. or a combination of them all?
SF: It’s complex, because it’s all of it. By definition, when designing a race car it’s a compromise - it’s not going one way, and then everything else is rubbish, you have to make everything great. From season one to two, we improved the efficiency a lot, we improved the power a lot, and from season two to season three, we’ve improved the weight and we’ve improved the efficiency again.
Remember, in Formula E, the power is capped. It’s not like it’s who has the most powerful car, the power is the same for everyone. You just have to make sure that your motor and your inverter is able to deliver that power constantly without overheating. Assuming you’ve done your job in that respect, the most important part of the job is efficiency.
For season five, it’s even more difficult. We have to generate a lot more power while being more efficient, and all while reducing the weight - so it’s a huge challenge.
Then you have to have other considerations - if you develop a really small motor to try to be really light, it will start to generate more heat, more quickly so that means you’d need a bigger cooling system. If you have a big radiator, you generate more drag, so your car’s not going to be as fast - it’s a tradeoff.
Then the gears - do you want one gear, two gears, three gears, or a bigger motor with one single speed; which has many benefits, or a smaller, lighter motor that has gears, but that generates friction in the gearbox. You have to be sure that anything you gain on the motor-side, you don’t lose on the gearbox-side.
It’s a huge amount of work to be sure that whatever you design is the optimum system. You also have to keep in mind where you are racing. If you are racing at Le Mans, you have to reach 350 km/h so that you would need a very different system with a lot of gears. [In Formula E] we rarely go above 220/230 km/h, so there is no point in developing a car that can go 350 km/h. So you always design the powertrain around the track layouts that you’re going to race at.
To make all this even more challenging, when we develop the car for the year, we homologate it before the season starts and the hardware is fixed for the year. So if we’ve done a really bad job, we’re stuck with it for a year. The big components we cannot change, however, during the season we can develop the software that manages the car, and there is a lot of performance to be found there.
RW: Last year, the team suffered from its car being overweight, and this appeared to have an effect on drivability. Having made improvements in that area, do you see it making a big difference at tracks like Monaco where drivability can be very important?
SF: It will make a big difference. For other race series, when they come to Monaco, it’s very difficult for them as it’s narrow, bumpy, difficult to overtake, and the grip is very low. For [Formula E], when we go to Monaco it’s the opposite. It’s the smoothest of all the tracks we go to, it’s less bumpy, and it’s the highest grip we see all year - apart from the chicanes, it’s also quite fast flowing.