Williams to supply hybrid system for Audi Le Mans car

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2012 Audi R18 e-tron quattro Le Mans car

Williams Hybrid Power will build part of Audi’s new Le Mans car, the team has confirmed.

WHP will produce the hybrid system energy storage supplier for the Audi R18 e-tron quattro.

The company has produced an ultra-lightweight electric flywheel and electronics system for the car, which was revealed yesterday. The flywheel spins at up to 45,000rpm and produces 150kW of power.

The Audi R18 e-tron quattro will make its race debut in the six hours of Spa on May 5th, a round of the new World Endurance Championship, prior to the Le Mans 24 Hours.

A statement released by WHP said: “The defining features of WHP’s flywheel made it the prime energy storage candidate for Audi’s project when compared to other technologies such as batteries, ultra-capacitors or mechanical flywheels.

“The main benefits of the WHP system are a high power density and correspondingly low mass, high efficiency energy transfer to and from the e-storage, the ability to continuously deep power cycle and an insusceptibility to performance or life degradation over a wide range of operating temperatures. In short, the technology is perfectly suited to the high performance demands of endurance racing.”

Williams Hybrid Power managing director Ian Foley said: “To be chosen as a supplier by Audi, the most successful brand in Le Mans’ recent history, is testament to the progress made by Williams Hybrid Power in its relatively short existence.

“Audi has won the 24 Hours of Le Mans a total of ten times since the year 2000 and we are incredibly proud and honoured to have been chosen to work with them and to have our hard work and technology recognised in this way. Such a high-level motorsport application represents the ultimate proving ground for our electric flywheel technology.

“This same technology can be used in everyday applications to save fuel and reduce emissions, for instance in city buses, that also require large power flows for short periods of time.”

Williams’ hybrid devices have also been used by Porsche in sports car racing.

Audi R18 e-tron quattro pictures

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Keith Collantine
Lifelong motor sport fan Keith set up RaceFans in 2005 - when it was originally called F1 Fanatic. Having previously worked as a motoring...

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30 comments on “Williams to supply hybrid system for Audi Le Mans car”

  1. Interesting to see Williams’ Hybrid Power seem to be having more success than the F1 team.
    How significant is Audi’s choice to go with the flywheel over batteries? I am not terribly up on the technology, but I assume electric systems in Le Mans cars make a bigger contribution than the limited batteries in F1 cars, so does this mean flywheels are better for high-performance hybrid engines? I’ve never even heard a car manufacturer talk about using flywheel hybrids in road cars, so will this even be relevant to road car technology?
    By the way Keith, I love the new front-page layout where you can scroll back through past articles.

    1. Flying Lobster 27
      1st March 2012, 12:12

      I think flywheels are bigger than batteries, which is why no-one has gone down that route in F1, but there’s more room to house them in LMPs. They’re probably less limited too: Toyota claims the TS030 can run up to 2km on electric power alone.

      1. Flying Lobster 27
        1st March 2012, 15:12

        I take back that bit on Toyota, in the sense that it isn’t relevant in the flywheel discussion. As eggry points out lower, Toyota is using different storage technology to Audi. This makes things even more interesting: diesel+flywheel vs petrol+capacitors…

    2. Flywheels were used in busses for pubic transport as early as the 40s/50s. The bus could recharge the flywheel at every stop; pretty brilliant. The reason it got abandoned was because of the massive gyro effect (no power steering back then, so you can imagine), but nowadays they probably could solve those problems. See http://en.wikipedia.org/wiki/Gyrobus

      In short: yes, this technology is very relevant for public use.

    3. I actually did my thesis on flywheel energy storage for vehicles.

      The flywheel doesn’t have to be that big. In one of the designs I had (which was very basic), the flywheel was 6.7kg, rotated at 9,000rpm and stored a pretty large chunk of a road car’s kinetic energy when it braked from 60-0km/h. When the speed of a flywheel is doubled, the kinetic energy is increased 4 times so imagine the energy capacity of a flywheel running at 45,000rpm!

      For racing purposes they’d be going for minimum weight and maximum rotational speed. I’m surprised Williams aren’t already using their flywheel storage in F1 but I suppose it’s just easier to buy the Renault system and focus on the rest of the car.

      1. @davea86 Williams uses their own battery KERS system, not the one made by Magneti-Marelli/Renault. It seems the batteries are more easily placed inside the tight confines of an F1 car with a big fuel tank.

        I think Renault recently commented on the fact that they had to work with Williams to make it fit perfectly with the engine, stating that its a remarkable achievement they have been able to integrate their engine with 2 different KERS systems (and the special demands of RBR to the MM/Renault system).

      2. Can you explain the difference between an electric flywheel and a mechanical flywheel?

    4. the reason Williams themselves don’t use is that flywheel is its shape. Flywheel is not larger or heavier than battery but its shape is quite limited. as you can imagine, flywheel storage should be sort of cylindrical one while you can make battery almost any kind of shape.

      There’s not so much room inside of chassis, also given that today’s capacity of KERS is highly limited by the rules, you would not want to KERS storage ruin your car’s layout. Usually teams locate flat shaped battery under fuel tank which is not able to be achieved when it comes to flywheel.

      Now you should know why flywheel is so successful in Sports car and GT. They’re two sitter and assistant seat is very good location for flywheel.

      1. That helps, thanks for clarifying everyone

  2. Que new thoughts about Volkswagen group getting into F1 with Williams!

    I always thought it was not so much Patrick Head stepping down from racing, but looking elsewhere than F1. In a way that highlights what we discussed a couple of days back about automotive companies looking for other series than F1 to promote their sporting heritage.

    By the way, it does show that Williams have good know how and knowledge, just not the nack for employing current top level aero guys.

  3. I saw the Megafactories: Williams F1 documentary on Nat Geo HD the other day, it was said there are more environmental benefits to flywheels than batteries. It’s more complicated to dispose of a battery safely it seems. I’m pretty sure batteries are also heavier?

    1. Yeah good point.
      Batteries might be efficient in use, but the environmental impact on the production and the disposal of them is very nasty. Lots of chemicals and acids.
      A flywheel is just a heavy type of metal. Should be easy to recycle.
      The good thing about batteries for a performance point of view is that there is no gyroscopic effect, which there is on a flywheel. Essentially it tries to stop you from turning.
      I don’t know how Williams have solved that.

      1. Surprised to see two queries about this, the solution is quite obvious. Gyroscopes only resist rotation through two axis, the axis that it spins around doesn’t experience the gyroscopic effect at all.

        The solution is to mount the flywheel flat, so that it spins around a vertical axis, like a spinning top.

        This would also have the beneficial effect of resisting pitch and roll in the car, although realistically it’s probably mounted on a gimball to avoid stress on all the moving parts.

        1. As far as I know, that is exactly what Williams did!

          It seems that in an F1 car the exact placing of it in the car being less flexible than a batterie is the main disadvantage and the reason Williams uses batteries in their F1 car.

          1. In the Porsche 911 RSR the flywheel is placed in the footwell so it can be flat, I suppose this will be the same in the Audi R18. Obviously this isn’t so easy in F1 though which is why it hasn’t caught on.

      2. well cosworth (or engineers from) while building an engine for a MotoGP team which never actually entered because of a change in the rules (to 800cc) built an engine with 2 crank shafts spinning in opposite directions, this had the affect of cancelling out the gyroscopic effect. It was quite complicated and look promising but unfortunately never raced. I suppose this could be applied to flywheel technology and have 2 smaller flywheels spinning in opposite directions, could also make the logistical side easier by putting one in either sidepod? I’m surprised if they haven’t at least thought about this option.

  4. I’ve heard it suggested that Williams will likely use there flywheel system in F1 from 2014 as the new engine rules make that sort of system more viable.

    If you go back to 2009, Williams did do a lot of testing with there flywheel system & did plan to run it in F1 that year but found that packaging the system was impossible under the current engine regulations.

    With the smaller/lighter turbo units coming in for 2014 packaging a flywheel system is a more viable prospect.

    1. I think they resigned to using it when FIA banned re-fuelling.
      It would fit with the smaller tanks but not with the big ones.

  5. Had Williams not signed an engine deal with Renault last summer, I’d say they would be a good bet to be Audi powered at some point

    1. An extra engine Manufacturer can never hurt.

  6. If this is the future for F1, you’ve got to think Williams would look pretty good to cope with the changes a few years down the line. If they survive, fingers crossed.

  7. So now we have 3 kind of storage for KERS in Le Mans and F1. Audi chose flywheel over battery, Toyota chose capacitor over battery but F1 chose battery over others. I think flywheel and capacitor is more relevant to road car technology so it’s another sign of that F1 is being apart from road car technology.

    Anyway, it’s glad to see Williams is successful at least it comes to their branch. Now it’s time to score regular point then get on the podium, finally wins…

    1. Agreed. While I applaud F1 for trying batteries(it’s better than nothing) the WEC is leaving them behind technology wise.

      I mean, an AWD, turbodisel, flywheel hybrid racecar! That’s incredible. You don’t get much more advanced than that. It is to other racecars what the 959 was to other sports cars back in the 80’s.

      1. Flying Lobster 27
        1st March 2012, 16:21

        I’ve been thinking for half a decade now that the road technologies of tomorrow are no longer in F1 – they are at LM.

        There was already an interesting mix of cars in endurance – GT, open and closed prototypes, different engine sounds -, and it’s just getting better every year. I’ve been to Le Mans three times, and it’s great to see cars of different shapes and to hear different engines all in one race. Give me the choice between an F1 GP and a high-profile endurance race (6, 12, 24 hours I don’t mind), and I will take the endurance ticket anyday!

  8. Love the look of the Audi, but what’s up with the attrocious hook thing that connects the back fin to the rear wing? I think there’s a rule that they have to be connected but really?

    1. It’s not a rule, but the swan-neck rear wing pillars have proved to be more aerodynamically efficient than regular pillars when they narrowed the rear wing by 40 cm.

      1. Or rather “when the ACO mandated a 40cm narrower rear wing (1.6 m instead of 2 m) back in 2009”.

  9. If you had 2 thin counter-rotating flywheels mounted flat to the floor, imagine being able to slow one slightly relative to the other – you’d get a turning moment. Interesting way of trimming over- or under-steer, or just turning in more quickly.

  10. Good news for Williams! So are Audi and Porsche their two customers now? I saw the Megafactories program on NatGeo HD which was a great insight into WHP.

    This can only strengthen their financial position so hopefully things are on the up for them.

  11. James finch-knightley
    7th March 2012, 17:41

    From track to street:
    Audi drivers and engineers explain the importance of tyres

    All car drivers are aware that they are black, round and keep their expensive alloy wheels off the ground but not many appreciate the benefits of choosing the right tyres for their car and style of driving.

    Michelin has interviewed some of the team’s drivers and race engineers to find out why they choose to fit Michelin tyres and why they feel fitting the correct tyres is important from a racing and road car point of view. And no, it’s not because the tyres are supplied free of charge as race teams pay like anyone else.

    Unlike Formula 1, endurance racing tyres are closely linked, in terms of size and performance characteristics, to those used on high performance road cars. Endurance racing calls for tyres that will last as long as possible while offering high levels of grip in various conditions from their first lap to their last. As a result, in last year’s Le Mans 24 hour race, the No.2 Audi R18 TDI managed to race for 750kms on one set of tyres, and at speeds of up to 330km/h with three Peugeots in hot pursuit.

    In 2012 Audi will field two R18 e-tron quattro’s and two R18 ultra prototypes at Le Mans – all shod with Michelin tyres. The two hybrid cars will be driven by last year’s Le Mans winning trio of Marcel Fässler, André Lotterer, and Benoît Tréluyer with Dindo Capello, Tom Kristensen, and Allan McNish in the other car. The R18 Ultra will see Loïc Duval joined by Timo Bernhard and Romain Dumas with the other R18 Ultra driven by Marco Bonanomi, Oliver Jarvis and Mike Rockenfeller.

    In the video, drivers Allan McNish and Tom Kristensen, and race engineer Howden Haynes share their views and experiences of tyres and talk about how innovation in motorsport benefits drivers with better cars and tyres.

    Video Links:


    For all the latest news on the Le Mans 24 Hours please visit http://www.mymichelin.co.uk/race-series/24-Hours-of-Le-Mans

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