Formula 1's powertrain powerplay

The year 2014 brings with it arguably the most radical technical changes in the 60-year history of Formula 1. Not only will engines be downsized by a third, but the V6 units will gain eco-friendly gizmos galore, including electrically-driven turbochargers and 500bar, high-pressure fuel-injection systems.

Having previously spoken to heavy-hitters on the engine and electronics front, I've now had the lowdown on 2014 technology from F1's primary KERS and fuel injection supplier, Magneti Marelli.

Kinetic energy recovery systems, known as KERS, were introduced to F1 in 2009 to much fanfare, but almost immediately disappointed early adopters such as Ferrari, McLaren and BMW Sauber - while Toyota, the world's largest producer of automotive hybrid drive systems and at that point still in the sport - rejected the device outright after a single pre-season test due to it being technically inferior to its systems available off the showroom floor.

Of that year's 17 rounds, just three were won by KERS-supplemented cars, while the season itself was dominated initially by Jenson Button and Brawn before Red Bull won the last three events. Saliently, neither team used KERS - the benefits of 80bhp, six-second bursts per lap proved insufficient to overcome the inherent mass (+30kg at that stage) and weight distribution penalties - leading to agreement within the Formula One Teans' Association to outlaw the device for 2010.

After a development hiatus, KERS returned in 2011, immediately proving its worth and becoming a must-have among the frontrunners. In the interim, the sports's governing body, the FIA, confirmed that hybrid systems were very much part of F1's future landscape. Additionally, its 'green' 2014 regulations specified a doubling in output and burst duration, with turbo compounding, in which an impeller drives a motor/generator also being permitted. This motor could then drive the compressor for reasons that will soon become clear.

Brawn won the titles in 2009 without KERS © LAT

Back in September 2008, prior to the introduction of KERS, this column exclusively interviewed Roberto Dalla, Magneti Marelli's director of motorsport, on the then-novel topic, and in Monaco this year the Italian and his colleague Keyvan Sangelaji, the company's chief technical officer, provided an insight into the challenges posed not only by energy recovery systems of the future, but also fuel flow management systems operating at astronomical pressures.

The switch from the originally-mooted in-line four-cylinder 1600cc power units running at 12000rpm to V6 engines of the same capacity but spinning at a maximum of 15000rpm as replacement for the current 2400cc V8s was only confirmed last June after major political upheaval.

Only thereafter were suppliers able to commence serious development, for not only did the configuration of the units change, but rev limits were increased - resulting in issues regarding the packaging and motor/generator, which need to run at 120,000rpm on exhaust-driven units (known as ERS-H), whereas wheel-driven (ERS-K) devices will run at the present 40,000rpm.

It has long been known that the K in KERS would be dropped as these devices no longer recover solely kinetic energy. Thus ERS is the global term, but increasingly F1 is distinguishing between the two units, referring to them as ERS-K (kinetic drive) and ERS-H (heat driven).

The units will have a combined output of approximately 210kW, being split 120kW (-K) and 90 (-H). The former will feed directly into a four megajoule energy-storage device - likely batteries, although supercapacitors (as per Toyota's Le Mans system) or flywheels (Flybrid, Williams Hybrid Power) cannot be excluded. The ERS-H output, meanwhile, can be channelled to an electric motor to spool the turbo to reduce lag, directly to the wheels, or into a storage system.

KERS is now used by most F1 teams © XPB

KERS development since 2009 means that units are now around 50 per cent lighter and smaller, and are now take up around 17kg for the three constituent parts (motor/generator, ECU and storage device), and Dalla believes this will rise by around 30 per cent to 23kg for a doubling of output and burst duration.

On the ERS-H side, he believes the units, approximately baseball-sized, will come in at 5kg. In a nutshell, ERS will add approximately 28kg to the overall weight of an F1 car in return for 210kW. Not a bad exchange - an almost 300 per cent power increase for 90 per cent of the mass penalty of 2009's units!

While ERS-K systems are effectively bigger-number versions of existing KERS units, ERS-H technology has no precedent in automotive applications.

"ERS-H is very challenging, because the motor generator will run roughly at three times the [KERS] current speed..." explains Dalla, resulting in Magneti Marelli starting from scratch in this regard.

"We are investigating two different solutions," he says. "One in which ERS-H is on the cold side of the turbo; the other with the motor generator staying in the middle, between the hot and cold side. We are developing both solutions. You can understand both have peculiar characteristics, but in particular the version in which the motor generator is in the middle, in terms of temperature, in terms of stress, we think we face a challenging situation.

"[Another] aspect that we are strongly convinced will work in the future is being able to drive the turbo with an electrical motor and not through the flow dynamics of the exhaust...

"In the regulations there is a direct connection between the -H and the -K without any [regulatory] limit. I'm sure this will be an area where all teams will do their development, because it will be out of limit, and, based on that, we have developed benches in order to enable the two devices to talk to each other."

To this end Marelli will continue to provide support to its contracted teams in their customisation of energy-recovery devices, as is presently the case with Renault (four teams, each with unique systems) and Ferrari (three teams), although for obvious reasons this support will be both wider and deeper.

Dalla's work will make new ERS units far more efficient than the KERS used as long ago as 2009 © Magneti Marelli

"Certainly what we discovered from [recent] experience is that you have to develop the solution as a system, so it is wrong for us to go to customers and say, 'this is our motor generator, this is our electronics, you take the battery and plug all [these] together'. You must have an integrated solution on the motor generator and on the electronics, with solutions that match their requirements related to the system."

The systems obviously need to 'talk' to the standard McLaren Engine Systems ECU specified by the regulations, and Dalla admits that the two companies have been in contact.

"This is totally logical, because you will have a new engine, new powertrains and teams want to be more free to develop. So probably we have to talk in a little bit of a different way [to the recent past], but in any case we will continue to talk." For more on this topic refer to the interview with MES CEO Peter van Manen.

While the new technology can be perfectly transferred to road cars, F1 has steered clear of introducing four-wheel-drive hybrid systems - which road-car manufacturers are increasingly adopting.

"You open a big item on which I had several discussions in the past," explains Dalla. "You know that Formula 1 has tried to limit the driver aids. As soon as you consider putting KERS in front of the car, to drive the front wheels, you enter an area where several persons (the FIA - as four-wheel drive would necessarily provide a modicum of traction control?) do not want to enter. From a technical point of view, certainly a Formula 1 car, more than a GT car, has a weight-distribution problem, so having a motor in front of the car is a difficulty."

So, two-wheel KERS it is.

In addition to ERS-K and ERS-H, 2014's regulations call for high-pressure (500bar, a more than five-fold increase over current engine pressures) gasoline direct-injection systems, with fuel-flow rate used as an economy driver that will fuel-flow management absolutely critical under the 'green' regulations. For more on the subject, refer to the interview with Renault's Rob White.

"This is another extremely important development for us, also because our road-car department is working on this technology, so we have much bigger experience than on hybrids," admits Dalla. "The main target that the regulations stated was to go to 500bar. Today, road cars have 200bar.

Keyvan Sangelaji is another of Marelli's experts

"It is extremely challenging for racing, and it's an extremely important experience for road cars, because what my colleagues are seeing on the road-car side is that they increasingly require higher pressures. So we took on board this issue with a lot of big energy. Today we have a very young solution of 500bar injectors that have been running for several months.

"I [say] 'young', because this is a completely new solution based on completely new technology, and the fact that it is young is, for me, a positive thing because I'm pretty sure we will be able to follow the need of the engine people as soon as they start to play in detail on this injector. I don't want to say gasoline direct injection [GDI] is more important than KERS, but it is certainly as important as KERS. Integration between the GDI system and the engine will be very important."

"Our approach on the injector started in 2003/2004 when I joined Marelli," explains Sangelaji. "We designed an injector for racing, not taking the injector from road cars and adapting it for racing. We started to design an injector for track racing, giving all the flexibility that racing teams need."

It is clear the GDI injectors are a development of those currently supplied to 100 per cent of the current grid, although the nature of the application and (necessary) location within the combustion chamber means they will double in size to a cylindrical 20x20mm.

"We developed the basic technology for the 500bar [system] that allows us to play with different variables. Things like dimensions of the droplets, directions of the jets and the penetration - we give a wide range of tools to the engine builder to design the proper injector for their use and to optimise the fuel consumption," he adds.

"The key point," says Dalla, "is that in this kind of injector the nose will be very important, because you have to put it inside [the chamber]. On the nose side you can do what you want, depending on space. So if you consider we're moving more than five times the current pressure, again the increase of dimensions is not proportional.

"We achieve these kind of things because we worked on the magnetic material of the injector, and we worked on the way to drive this kind of injector: how much current, this kind of profile. Today we achieve this very interesting solution."

In fact, although the engine regulations have been widely derided - particularly by race promoters who would not know a diesel engine from a donkey - the technology is not only utterly relevant, but a massive engineering challenge for teams, engine manufactures and hi-tech suppliers, with the added bonus that 'win on Sunday, sell on Monday' once again becomes significant.

Magneti Marelli KERS components © LAT

"For us [the new technology] is a very challenging development, because we believe in KERS in the race, and we support totally the FIA initiative to have a powertrain system that in 2014 will reduce fuel consumption by 30 per cent while keeping the performance. That is a good concept that we apply also on road cars. So we support this kind of development 100 per cent."

The fact that on the very day the interview was conducted all team principals present in the FIA's Monaco Press Conference expressed their full support for the 'eco-friendly' regulations not only proves that the FIA is in tune with the times, but that road-car technology can once again benefit from Formula 1 developments.

Yes, they did express reservations about the cost of the new power units - and these will certainly be more expensive than the antiquated V8s whose roots stretch back to the past millennium, but that's a story for another day...