At the recent Motor Sport Business Forum in Monaco, FIA president Max Mosley confirmed in his keynote address that the Kinetic Energy Recovery Systems (KERS) permitted in Formula One next year will continue to be entirely 'open' in their technology. The video of his speech is available at:
www.fia.com.
KERS flywheel technology could power road going Alfas and Ferraris in the near future. Design by Raffi Minasian and Christopher Keller.
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This decision is not just of significance to Ferrari and the other F1 teams but to to all manufacturers of road cars of every color, and to their potential owners. It's now almost certain that the car which wins the World Championship next year will be a hybrid, and most, if not all, the other cars competing will also be hybrids. As a consequence, BMW, Ferrari, Honda, Mercedes, Renault and Toyota are going to get really enthusiastic about hybrids (some of them are already!), propelled by gasoline approaching $10 a gallon in Europe and goaded by new legislation from Brussels, Tokyo and Washington. Max Mosley wants F1 to be a crucible for the development of road-relevant, fuel-efficient power-trains. The FIA has now ensured it's 'race-on!'
Layout for a hybrid supercar. The two flywheels provide a power boost. Drawing by Chris Ellis.
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Open Technology
The decision to keep the KERS technology 'open' contrasts with the FIA's original intention to enforce an electrical solution by single-sourcing standard super-capacitors and doling them out to the teams, graciously allowing them to use their own motor/generators and controllers. 'Open technology' now means that F1 hybrid drives can use batteries or capacitors, hydraulic pressure vessels or high-speed flywheels to store energy temporarily between regenerative braking and adding KERS power to engine power to provide extra urge for overtaking. Although only battery-based hybrid road cars have been announced to date, hydraulic systems are showing potential for delivery vehicles and garbage trucks. Static flywheels for computer backup, etc, have high-speed motor/generators attached to their shafts, and effectively operating as 'flywheel batteries', and we may see this approach used on some F1 cars. However, the (theoretically) most efficient and potentially least-expensive approach is to connect the flywheels to a special form of continuously variable transmission, and then to the driving wheels. This provides an all-mechanical 'energy pathway' between the flywheel rotors and the driving wheels. By avoiding the four loss-incurring energy transformations required in a battery-based hybrid system (mechanical to electrical to chemical to electrical to mechanical), a 'mechanical flywheel' system should prove the most efficient.
A new Alfa Romeo--with 60 mpg, 450bhp, 4WD. "Post"-Graduate indeed. Drawing by Chris Ellis.
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While F1 usually takes pride in using the most expensive solution to any problem, it will eventually be forced to prove which is the most efficient KERS solution. If this also promises to be the least expensive, then expect to see it enter the road car market at the Ferrari level by 2010 (but not necessarily in a Ferrari!), and reach the Fiat level around 2015.
2009 and 2010 Regulations
For next year and 2010, the FIA is limiting the output of the KERS to 80bhp (strictly speaking, 60kW), to drive the rear wheels only. Unlike road hybrids, the race cars are not allowed to gather surplus engine energy (during cornering, etc); the only input permitted is from regenerative braking, and this is also limited to 80bhp. This is particularly perverse, as ordinary friction brakes are (roughly) constant torque devices, with peak power falling as the car's speed falls. Imagine a regulation that limited the power of a car's disk brakes! This regulation also has the effect of adversely affecting the brake balance by biasing it rearwards as the car slows, if the KERS attempts to recover the maximum amount of energy allowed by the rules. However, the FIA gets around this problem of its own making by limiting the total amount of energy that can be output per lap to 400kJ. This translates practically to less than seven seconds of an additional 80bhp per lap, which doesn't provide much of an edge. Seven seconds is a lot less than the total braking time per lap for most circuits, which stretches to over 20 seconds in the dry at Monaco, considerably more if wet. This means efficiency won't matter much in 2009 and 2010, but it certainly will when KERS get serious in 2011.
The KERS equipped Ferrari as designed by the team of Minasian/Keller. The body side character has a ribbon effect leading from
the front wheels and sculpting the body along the belt
line. This typical Italian character presents a muscular
profile while hinting at a feminine form.
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The proposed regulations for 2011 and beyond are much more interesting, and also very relevant to road cars. Peak KERS output is permitted to rise to 268bhp (200kW), and can be applied to the front as well as to the rear wheels. At last, four wheel drive, if only for the KERS! But then you probably wouldn't want to put more than 270bhp through the front wheels of a car weighing only some 1,350 pounds (including driver), particularly with a rear weight bias. The 400kJ per lap restriction is lifted, to be replaced by a '400-600kJ limit per straight'. This apparently means the exact figure has yet to be decided. This limit is there to prevent top speeds from becoming really dangerous, given the parallel regulated reduction in downforce and associated drag and the retention of the 'frozen' 2008 engines rather than the much less powerful engines originally proposed for 2011. However, the total permissible 'KERS peak output time' will now significantly exceed total braking time per lap on most tracks and, as input is also limited to 268bhp, KERS efficiency becomes a key performance metric, because the car now needs to recover braking (kinetic) energy as efficiently as possible, and then use it to help restore the car's kinetic energy with the minimum of losses a few seconds later.
KERS for the Alfa Romeo
A typical production hybrid road car is hard pressed (don't press too hard, or you'll invoke the friction brakes!) to achieve 35% efficiency in slowing gently from 30mph to a stop and then accelerating back up to 30mph. The target for a 2011 F1 KERS is at least 70%, because the teams already know that certain systems should be capable of meeting this objective. Of course, in an F1 car a more important metric might be 200 down to 100mph and back up again, where aerodynamic drag losses will have a significant impact on the overall regenerative braking efficiency, but the need for a very efficient KERS clearly remains strong. A KERS technology which is probably highly efficient in Formula One is going to be of real interest to the road car side of any of the participating manufacturers, and most of the others. Note that both Audi and Ford already take part in the discussions between the FIA and the 'F1 Manufacturers'. Imagine the city cycle EPA numbers for a Prius IV if Toyota can eventually double the efficiency of its regenerative braking!
Even more interesting, let's imagine a post-Graduate successor to the current Alfa Spider, which needs to be a compelling offering when Alfa Romeo returns to the US market. The most powerful engine available in the current two-seater is a front-mounted transverse 260bhp 3.2 liter V6, which comes with four-wheel drive. The new Spider also has four-wheel drive, but is a 2+2 (post-graduates tend to breed). Low down under the hood is the surge power unit connected to the front and rear final drives. It's twin contra-rotating rotors are located longitudinally and side-by-side, where the oil sump would have been in the old car.
Proposed as a Ferrari, the Minasian/Keller concept could also work for a U.S. bound Hybrid Alfa Romeo. Initial
concepts were done with attention to a low profile frontal
area which rapidly gives rise to a tight cockpit. This
emphasizes a tight, crouched position even at rest.
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Also connected to the rear final drive is a transverse, direct-injection, 1.8 liter turbocharged flexible-fuel straight six capable of producing 250bhp on E85 or 210bhp on gasoline. The Surge Power Unit adds 200bhp, to give a combined peak of up to 450bhp. Fortunately, the Spider is considerably heavier than an F430, or there might have been complaints about 'under-cutting' from Maranello. It could be argued that four cylinders should be more than enough and might save a little more fuel, but this is a spider, where the sound of a straight six is music you will want to enjoy, and it's for America, where only the very poor drive fours. The transverse straight six is mounted just behind the rear axle line, but is thin/short enough to allow a short but wide and deep trunk behind it, ideal for trips to the mall. For vacation baggage and/or golf clubs, the front trunk above the cool (in every sense of the word) surge power unit comes into play.
Despite all the power, the very efficient Surge Power Unit helps produce an EPA city cycle figure of over 70mpg. The low height, the low hood line and the full undertray (all made possible by moving the engine to the rear) combine with the relatively small, directly injected CAI engine to give a highway cycle figure of over 60 mpg. At a steady 75mph with the top up the Spider still gets over 55mpg. Optionally, the new Spider can be equipped with a 30kW electric motor integrated with the Surge Power Unit, plus a battery providing up to 20 miles of engine-off range installed in the front trunk. This then allows an infinitely high mpg figure to appear on local trips, but without penalizing the vehicle with excessive weight on more sporting occasions.
Is this the best of both worlds?
Hopefully, we'll soon find out.
