Industry Interview, Interviews, Issue 49 - Summer 2013

Interview with Jon Hilton – Flybrid Systems

Flybrid Automotive Limited’s core product is a high-speed flywheel based Kinetic Energy Recovery System (KERS), which it claims is a superior alternative to electric hybrid systems for cars. Road car applications are coming, Flybrid says. Dave Leggett spoke to co-founder Jon Hilton about the company, its technology and the latest developments.


What are you busy with right now and can you describe the main elements and responsibilities that come with your role?

I’m managing director here at Flybrid and this job has changed quite a lot in the last couple of years. Until a couple of years ago I was responsible mainly for sales and marketing.

We decided about a year and a half ago to promote a group of our guys to management. Doug and I, the two business owners, gave the day-to-day running of the business to this group of managers in order to free our time up to look for finance.

That was something of a priority, we had to raise finance in order to do all the things that we wanted to do. That’s been pretty successful; we received substantial investment from Torotrak in March of this year and now my role has changed again, as we no longer have to look for money.

Now I have a bigger picture to concern myself with, particularly the future growth of our business and how we move on to manufacture our products for clients.

There’s also Tier-1 licensing for mainstream cars with clients like Volvo Cars looking to buy the product in 2017, so I’m out there trying to find Tier-1s to make it for them.

Can you describe the main activities of the company and the resource base?

We’re in the field of kinetic energy recovery systems (KERS) and all of our work is in that area. And we do many things related to that, so while we started off just with the flywheel, we’ve ended up making the transmissions and the hydraulic and electronic control systems, creating software and there’s also product support out in the field. So we’re doing everything from buying steel bar to selling complete systems running in vehicles.

We have twenty people in the company on two adjacent units on the Silverstone Technology Park and we are just at the point of expanding.

You manufacture yourselves?

We do a proportion of the manufacturing inhouse, such as the flywheel hub, we make about 20% of the parts in-house at the moment and we are just about to invest in more machinery to enable us to make more ourselves.

What are the key advantages, as you see it, of your flywheel based KERS over equivalent battery based systems?

The key advantage is cost. We are about a third of the cost of an equivalent power electric system. We are also more efficient, capable of a wider [operating] temperature range and we have a long life. We can do the full bus life, for example, and around six million full charge-discharge cycles in a bus life, perhaps a million kilometres of use. Buses can’t do that on batteries, they change them after around five years and that would be two battery replacements at maybe GBP 25k each during the life of the bus.

The benefits of our system are cost and performance.

The electric battery is basically very expensive and they are not going to be more than a niche product in our view. And the emission test drive cycles are changing with the move, from 2017, to the World Harmonized Light Vehicle Test Procedure (WLTP), from the current NEDC standard in Europe.

It will suit us, but it will mean a harsher duty cycle than the existing one and it gets very difficult for the cheaper end of the electric systems where you need more power, 30-40 kilowatts on a normal-sized car.

You just can’t get that sort of power out of the low voltage electric systems. And as soon as you go to the full electric hybrid where you have to separate the earth from the chassis of the car, above 60 volts.

With a secondary electrical system, it becomes much more expensive because you are carrying high voltage, at that point, our system looks even better.

And the cost and performance benefits you describe for flywheel-based KERS are becoming widely accepted in the industry?

Yes, I think so, and more widely accepted as time goes by. It’s always reassuring to potential clients to see other people in the same space, doing the development work and developing flywheel based hybrid products. As more clients and users of our system break cover, the level of confidence goes up. Nobody asks us now whether it works; we’ve done enough high profile programmes for people to be able to see that it works. And we’ve done much more work in the private domain than the public.

The performance aspect is important and that’s something that Volvo likes. Our system provides high power with a small amount of storage. We can capture a lot of the braking energy and in real-world use, we’re even better than the test cycle.

I guess everyone is aware of the F1 application, but how useful was that experience?

The original Flybrid Kinetic Energy Recovery System (KERS) was a small and light device designed to meet the FIA regulations for the 2009 Formula One season and the development work was very useful, even though our system wasn’t actually used by our client in the end (Honda pulled out from F1 before racing with it).

Without that we would have struggled to get as much product development work done as quickly as we did; it was quite well funded.

The Formula 1 rule-makers did a really good job of setting a specification that was sensible and the product we developed, the storage and power levels meant that it was about the right size. In fact we went on to use very similar flywheels and transmissions in things like the Jaguar demonstration car and later on in the Volvo.

Commercial vehicle applications also seem significant. What are the benefits of the flywheel KERS that have attracted bus operators?

The key thing with commercial vehicle operators is that it has to be affordable with a payback over a reasonable period of time. With electrical systems the payback can be over ten years. We’re half that and once we have mature volumes out there it’s coming down to three years or less, at which point it’s a no-brainer to fit our system.

And frequent stop-start operation is particularly important to energy recovery?

This is an interesting one. The energy recovery will still be very significant on a vehicle braking just a few times, but braking from speed. It’s about kinetic energy and how fast you are going when you decelerate to stop. We have looked at a variety of drive cycles and journeys. For example, a colleague has a journey to work that is mainly dual carriageway but when he does brake, it’s typically from a relatively high speed to, say, negotiate a roundabout and then there will be a few more accelerations and braking, so there’s actually quite a big energy saving to be made.

It’s not the case that you will only get the benefit on frequent stop-start driving cycles. In fact, if they are very stop-start they may be a bit slow, like refuse trucks. We can get 20% savings on refuse trucks, but they’re not as good as you might think because they are very slow. It’s all about half the mass times velocity squared and that v2 element is obviously very important.

How about reliability and the vacuum-seal housing for the flywheel?

It’s not as difficult as you might think. On the shaft are two lip-seals and in between is a quantity of oil-based fluid. The pressure of that oil-based fluid is just above atmospheric so that the air cannot get in. From the fluid into the chamber is just over 1 bar, so you’re sealing oil and not air.

There’s a little bit of seepage across that seal, but every time the vacuum pump runs, it sucks up any liquid that’s leaked into the chamber and puts it back in the tank, so it’s a closed loop system. We can manage it pretty easily. The seals are like a crankshaft seal on a typical engine and because the seal diameter is very small, the speed is not that scary. We can’t break them, despite hundreds of hours on the test rig at accelerated speeds.

They’re looking really good to do whole vehicle life, no problem.

So manufacturing and scalability are not difficult issues?

On the manufacturing side, it’s very important to balance the flywheel extraordinarily accurately and we have had to invent our own balancing machine to do that because no balancing machine we could buy was good enough. We have invented that now and it works reliably and will scale up okay. We can do 25,000 flywheels a year on one machine.

Turning to road car applications, what’s the state of play of the Jaguar led demonstrator project?

That is finished now. It was sponsored by the UK Technology Strategy Board, so government funded, and it illustrated a 22.4% fuel saving on a real world driving cycle including the benefit of stop/start. The programme was aimed at CO2 reduction technologies so we didn’t do any performance work as part of that.

However, we have had the car back at Flybrid over the past year and we have been doing some performance work, because to get the best out of the system you have to show both economy and performance.

Our push is to downsize the engine a bit and put it back to original performance with the KERS boost and take the fuel consumption saving on top of that. Volvo talked about a 25% fuel saving versus a car of equivalent performance and that’s a very sensible way of putting it, in our view. That’s where we like people to be pitching it.

Do you think Jaguar will pick up this technology on a production vehicle?

We hope so and they certainly remain interested in the programme. The key for them will be pricing and Tier-1 involvement and that’s also where we are with Volvo. We need to make a license arrangement with a Tier-1 supplier that is capable of manufacturing in mass volume for these sorts of companies. Neither is prepared to fund the programme all the way to production, with things like design for manufacture, design for assembly, setting up an assembly line and tooling on their own numbers alone. They really want to share that.

So that’s the big commercial challenge for you right now?

Yes. We need to license to a Tier-1 in order to get this technology into production for mainstream cars. Volvo have been really helpful to us, they want a Tier-1 involved, with things like press coverage. I can say that we have a lot of interest from a large number of Tier-1s and it’s an interesting challenge from our point of view. We have to know who is best to license to. None of the Tier-1s supply everybody. Some of them, for example, know Volvo very well and they might seem like obvious choices. But maybe they don’t know Jaguar so well or some of our other clients who are not yet in the public domain. Finding one company that can service all of the requirements is difficult.

And Volvo is the lead OEM amongst your clients?

Yes, that’s probably a fair way to put it.

What Volvo model would, potentially, be first for this technology?

They have made space on the new platform they call SPA for it in the rear of the vehicle, connected to the rear wheels. That platform will cover everything from Volvo’s 40 series cars to 60 series, most of what they make.

And there’s already a trial vehicle…

That’s right, the current S60 saloon.

So when could we see your flywheel in a production Volvo car?

Volvo are asking for 2017 and we’d be delighted to do that and we are pushing to achieve that. We need to get the Tier-1 side of things resolved over the next year.

The tie-up with Torotrak is an interesting one, another technology development company. What synergies does that tie-up provide?

We’ve been a Torotrak licensee since 2007 and we have been using their variator in our KERS product, so we know their product and we know them very well. The Volvo demonstrator vehicle uses a Torotrak CVT.

We share a lot of high speed and rotating things, precision stuff; there are also very similar control systems. We developed a control system to control their CVT and developed that same thing for clutches and other things that we need in our device. We are working with the same kinds of electronic control units, valves, sensors, fluids.

And we’re both at a similar production stage regarding production for mainstream. They have done their license deal for main vehicle transmission with Allison. And they could be a partner for us, maybe…

Torotrak has been through the same kinds of processes we are going through. We have gone about things a bit differently but we are arriving at a similar place at a similar time and we face a number of similar challenges, particularly in the manufacturing area where we are getting ready to make our product in low volume for the bus application in particular.

We are wanting to invest in factory, line, machine tools and so on, and they are in the same position with their variable supercharger product. There could be an opportunity to combine our requirements, do the work only once and potentially build one machine shop to make both sets of bits. The machines involved are pretty similar, we’re talking hard steel round and turned and milled bits that go on the same machines.

And the 20% stake that Torotrak took was also important?

Yes, absolutely. The money raised has been vital to keep the low-volume bus project going at a timescale that we needed to hit. Torotrak understands what we are doing and where the technical risks are.

Could you do an IPO?

We could have done that, but we don’t really need to do that now. If Torotrak take the remaining 80% equity by the end of this year, which we think they will do, we’ll be okay for funding.

How do you see the future for Flybrid over the next five years?

I think you’ll see a big change. We’ll get into the market at low-volume at first, extending on that timeframe to production cars. I think what we have is going to go absolutely massive. Back in 2007 we looked at the alternatives [to our technology] that were available and concluded they were all rubbish.

Here we are, six years later and the alternatives have not significantly improved. Our technology really does work. The alternatives are poor and they are not fixing that, despite the talk. Batteries are not getting cheaper and technology is being added to address the fundamental issues of power capability and longevity.

Another important point is that the regulatory landscape is moving in our favour. The EU targets for CO2 emissions in 2025 are very ambitious, 68 to 75 grammes of CO2 per km, and we have a solution that is mechanical and avoids high voltage electrical to get there. We have proper long term future-proof solutions that really work and avoid the complications and cost that come with electric solutions.

Overall, I think we are sat in a really good place. With the right Tier-1 support it could really fly and in five years’ time, we could be swimming in car programmes. The issue for us will be managing the high growth that could be ahead.

Writer: Dave Leggett


Flybrid Systems

Founders Jon Hilton FIMechE CEng and Doug Cross MIMechE CEng have a strong racing background and their last ‘real jobs’ were working for the Renault F1 Team where Jon headed up the UK based Engine Division as Technical Director.

Between them they have approaching 25 years’ experience at the top level of world motorsport.

Jon has a long record of success in motor racing going back to Michael Schumacher’s first F1 Championship victory in a Benetton powered by a Cosworth V8 for which he designed a number of parts. International Touring Car Championship victory with the Opel Calibra and Manuel Reuter in 1996 signalled his first major wins as Chief Engineer of a whole engine programme, and after five seasons at TWR Arrows and four seasons at Renault F1 his achievements were capped with a fantastic back to back double victory for Renault F1 and Fernando Alonso in 2005 and 2006.

Doug Cross shared the Renault victories and as Design Manager of the UK based Engine Division played his part in the significant engine performance improvements that helped to secure them. Previous employment at Toyota F1 and Ricardo Consulting Engineers gave Doug a strong engineering background combined with commercial understanding.

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