A NEW FORMULA FOR FORMULA E

A NEW FORMULA

FOR FORMULA E

Electric racing returns this month with new power

trains and other improvements

Formula E cars emerge from their team garages with a suddenness

that seems incongruous. Even on their way to practice laps, the drivers

turn their cars sharply from the garages and accelerate in apparent

anger along the asphalt leading to the circuit. When the second

season of the electric formula-racing series begins in late October, in Beijing,

they may be able to drive with even more aggression: Unlike during the competition’s

first season, each team can now choose its own power train and will

also employ a host of smaller technology tricks learned from last year’s racing.

The first season was dominated by close jostling among the drivers: It began in

Beijing with a crash that upset the two front-runners. Over the course of the next

10 races, no single team or driver took a definitive lead, and the championship

was up in the air until the final lap of the last race. That may have been in part

because the 10 teams were all using the same hardware. “This is the last year of

such close racing,” predicts Deogracias Vidal, a mechanic for NextEV TCR, the

team whose driver, Nelson Piquet Jr., won the first season’s individual championship.

“Next year’s motors will make a big difference,” Vidal says.

In addition to the motors, the other big changes will be in the inverters and

the gearboxes, but the teams have let only limited details emerge. McLaren built

the power trains in the first series, but eight manufacturers have stepped into

the fray for the second season of Formula E. McLaren will offer an upgraded

version of its motor, dropping the number of forward gears from five to four.

The Abt Schaeffler Audi team will use

three gears, the e.dams-Renault team

will use two gears, and NextEV TCR

and DS Virgin Racing are using directdrive

systems, which are effectively

just one gear—although Virgin will use

a twin motor.

Fewer gears means less time spent

switching among them: In one race last

year, there were 23 gear changes per lap

on average, adding up to more than a

second of lost power and charging. But

less shifting comes with an efficiency

cost, as the motor will spend more time

outside its best performing range.

The Amlin Andretti team is replacing

its off-the-shelf inverter with a custom

one. “People who are buying qualified,

highly reliable things may not

get to enjoy the latest improvements

in what’s on the market today,” says

Nicolaus Radford, chief technology

officer of NASA parts supplier Houston

Mechatronics, the company that built

Andretti’s new motor and inverter. But

custom gear can come with more integration

challenges, as Andretti experienced

when it missed days of track

testing in August and wound up changing

back to its old motor.

In addition to hardware changes, there

is room for applying lessons from the first

season to racing strategies, says Peter

McCool, technical director of Team Aguri.

Teams now have a complete set of performance

data from 10 racecourses, at least

eight of which will feature in the second

season. McCool’s team has written its own

software to guide battery management,

he says, and it should be able to get better

performance next year. Battery management

is particularly important because

rules limit both maximum power output

(150 kilowatts last season) and total

energy use (28 kilowatt-hours last season).

Drivers can recharge the battery a little

by coasting and braking, but “energy

in and energy out doesn’t come

for free,” says Gérry Hughes,

chief engineer of Team Aguri. For

example, charging and discharging

raises the battery’s temperature,

altering its performance.

Formula E’s unique restrictions

have forced teams with more

experience on the gas-guzzling

Formula One races and endurance

races such as Le Mans to be

more creative. Hughes calls it a

selling point for engineers like

him, who have worked on more

conventional motor-sport series.

Formula E “allows me to sort of

broaden my horizons in new technology,”

Hughes says. For one

thing, batteries are so foreign

to most motor-sport engineers

that they have had to seek outside

expertise. “Anything you can

learn over and above your competition

can stand you in good

stead,” he says.

Throughout the second season,

the battery maker Williams

Advanced Engineering will be

in the best position to learn

about battery use, since it has

access to all the data and it supplies

the battery’s controller.

The 10 teams generated about

60,000 kilometers’ worth of racing

data over the first season’s

11 races, says Okan Tur, Williams’s

chief technical specialist for the

batteries. “We’ll see how we can

use that data in the best way and

to guide us in our future battery

designs,” he says. In the second

season, teams will reuse the first

season’s batteries’ outer structure

and electronics, but Williams

will swap in new cells and thermal

control structures. “We had

some cell-level improvements in

the past year,” Tur says. “We’re

quite optimistic that it will result

in improved performance with no

design changes.”

Formula E’s founder, Alejandro

Agag, has made a lot of noise

about how the technology tested

in the series will someday reach

everyday hybrids and electric

cars. But that may not be the

most lucrative place to market

high-performance electric

motors and batteries. Hughes

says, with more mystery than

specificity, that one of Team

Aguri’s technology partners is

already “applying these types of

tech to other forms of transport

that don’t have wheels.”