Now we checks out the future of Formula E at Venturi

The more energy you can recover on track, the further you'll go.

Jonathan M Gitlin

Elle Cayabyab Gitlin

Venturi engineer Louis-Marie Blondel (left) talks to us about Venturi's Formula E program and the powertrain development process.

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When we last met up with Venturi, it was in the Buckeye state. We'd gone to meet VBB-3, the electric land speed record car it's built with the Ohio State University. Meanwhile, back at the company's Monegasque HQ, work has been underway on next season's Formula E electric race car. Since we were in that neck of the woods, we popped over to the company's home base to find out what it has in store. These days it's better to think of Venturi as an engineering and design firm for electric powertrains, rather than a low-volume sportscar producer. It will still make you a road-going (or maybe even off-road) EV sports car, but you'd have to ask nicely and you may have to wait a few months to take delivery. The company is now focused on ever-better electric powertrains, and it does this by testing them in some of the most extreme ways possible.
There's the Antarctica, an eight-wheel EV for transporting French scientists around the South Pole. At the opposite end of the temperature and speed dials is VBB-3, designed to eclipse the internal combustion engine's top speed on sun-baked salt flats. And then there's Formula E. The organizers want the sport to be directly relevant for road-going EV development, says Venturi's Thierry Apparu. "It's why the races are on the streets." The lessons learned in all these environments funnel back into know-how that can be applied to EV powertrains that people will drive in the future.

Further Reading

Racing goes electric: At the track with Formula E, the first e-racing series

Ars checks out the new all-electric racing car series on its first visit to the US.

In its first season, all ten teams used identical cars, but from season two (which began last fall) the teams have been given some technical freedom. Everyone still uses the same chassis and batteries, but they can develop their own motor-generator units, inverters, and gearboxes. The rules require that power only go to the rear wheels, and there has to be a mechanical differential—so no clever torque vectoring twin-motor arrangements just yet. Venturi's VM200 motor is still limited to 200kW but revs higher and makes more torque than the spec MGU that all teams used last season. The transmission is also specific to the new motor—in this case a four-speed. For 2015-2016 the Dragon Racing team is also using Venturi's powertrain (although with their own software), although next season Dragon is going its own way.
The team is hard at work getting the new car ready for the FIA homologators, who are coming in late May to sign off on the car for next season. We didn't get to see under the bodywork of the development car, but Louis-Marie Blondel explained that in addition to mechanical and software changes, there was also a new crash structure under there. Blondel heads up development of the Formula E car for Venturi and talked us through the design philosophy.
"Each team works on the energy consumption with their own strategy. All the teams use the same battery and same quantity of energy—we have to manage ours better," he told Ars. The racing is getting very close, with just tenths of a second deciding race wins this season. While this might sound obvious, the more efficient car and driver are at recovering energy, the more they can use in the race. Energy lost to wheelspin or an overheating battery is energy than can't be used to get to the next corner faster than its rivals.
Battery management is key, as is driver style. "If he drives over the capacity of the car he'll use a lot of energy. And so he'll have to run slowly at the end of the race," Blondel said. Part of this management involves knowing how and when to change the amount of braking provided by the MGU versus the mechanical brakes at the rear. "Thermal management and energy management are the main problems for the race for Formula E. For example, if the battery is overheating, if you're at the limit, you can't regen," he said.

Further Reading

400mph or bust: Meet the VBB-3, the world’s fastest electric car

This electric record machine is built by students at the Ohio State University.

At the start of the race (or after the pit stop when drivers change cars) the batteries are charged so there's no point trying to recover energy under braking. But as the batteries begin to deplete it makes sense to recover as much kinetic energy as possible. Particularly during the first stint; the more efficient you can be, the later you can swap cars. A later pit stop means fewer laps with the same size battery, so the driver can push the car harder and set faster laps. In the hybrids that you or I drive on the road, clever control electronics are constantly monitoring the state of the battery and will decide for themselves how to apportion braking between the MGU and mechanical stoppers. In Formula E, the FIA won't let teams automate this, so it's down to the drivers (with some help from the engineers) to monitor things and adjust the balance depending on race conditions.
More technical freedom—and cars that have enough battery capacity to complete the entire race—will have to wait a couple of years. "For season five [2018-2019] we'll have a new chassis and a new battery with a lot of energy. We hope we'll have the same weight but it depends on the technology of the battery," Blondel told us.
Weight is the enemy of all racing cars, and the current Spark-Renault SRT_01E is not particularly light—the car and driver together weigh 1980lbs/898kg. "It's very heavy, and we only have 170kW for the race. It's not a lot, which is why for season five we hope to find a new technology for the battery to have a lot of energy but with less weight," Blondel said. Should that happen, expect to see more manufacturers join the series. As we reported in February, Jaguar is already planning to join the fray, and we're led to believe that both Nissan and BMW teams are in the cards as well.
Listing image by Elle Cayabyab Gitlin