Racing green

Electric vehicles tend to conjure up images of sluggish, strange and ugly looking things that need to be overtaken at the earliest convenience. From the milk float to the G-Wiz, it's not stuff to win over the hearts of your average petrol head. So when it was announced that this year's Isle of Man TT would hold the first clean emission Grand Prix, you could be forgiven for picturing mobility scooters lining up at the start of the grid. But, you'd be wrong. The reality is going to be something very different. The TTX GP was only launched last June with the rules for entry being finalised in October. So it hasn't given teams the longest lead-time to develop respectable racing machines for the competition. But, like most motorsports, it's about innovating under pressure and coming up with the best solution with the resources available. For almost all the teams this year, that has meant using an electric powertrain. But that poses particular technologic engineering challenges as Paul Brandon, course director for Motorsport and Motorcycle Engineering at Kingston University explains: "It is a question of energy density. The energy available from 1kg of petrol is many times greater than that available from 1kg of batteries, regardless of their chemistry. Normally, teams use around 12 litres of fuel around the track. It would be the same challenge as saying, 'here is 3.5 litres of fuel, get yourself round the 38 mile course at race speeds'. That is essentially what we have to do with the batteries available. It is how you manage the available energy that is the real challenge. On the positive side, the overall efficiency of a petrol bike is around 32%, whereas an electric bike has an overall efficiency of around 90%." Brandon has led a team of six students and retrofitted an old NSR 250 rolling chassis with an electric powertrain. The decision was taken early to take this approach due to time and cost restrains. "We are very much along the road of lightweight solutions for performance vehicles," says Brandon. "We have a vehicle that will weigh around 160kg. It is not as powerful as some of the competitors but it is light." So far 24 entries from 16 teams are have entered the competition from all over the world including the US, India and Europe. Although many of the teams are keeping performance data close to the chest, those that have released some figures are quoting vehicles that can top 150mph and do 0-60mph in less than four seconds. So it is no surprise that all the bikes have to be rode by professionals with the relevant race licences. This creates some interesting design issues in its self. Most of the bikes will be directly driven by electric motors, but the riders have asked that the bikes feel like it is a changing gear on command, all be it artificially. Additionally, one rider has asked to hear engine noise relevant to the revs of the motor, as her riding style normally relies heavily on this feedback from the engine. "We can give the motor different torque and power characteristics," says Rick Simpson, director of Evo Design Solutions. "It depends how the riders feel around the circuit. Our program allows us to have up to seven different motor profiles. These give different acceleration and speed characteristics. Depending on what the rider would like them to be you could have a normal gear change feel." Evo Design Solutions is one of the front runners entering the competition. It is entering both the Pro and Open class with the difference being dual motors on the rear of the Pro bike to provide 45kw of power and 90Nm of torque. It also stores and releases compressed gas for further energy capture and generation during braking and acceleration. The bikes are made up of monocoque carbon fibre shell, with expertise offered by Peter Williams, who designed and then raced the 1973 Norton monocoque to victory at the TT. All the essential systems are contained within, or attached to, the body shape of the vehicle and bring down weigh to just 135kg. The famous 38 mile track incorporates over 200 bends and goes from sea level to over 400m in altitude. It is a tough circuit that is infamous for pushing both man and machine to the very edge and sometimes over it. Most teams hope to average between 70 to 80mph around the circuit with some even hoping to get close to 90mph. "We want this to be a credible serious option for racing teams," says Azar Hussein, who set up the competition. "We have always been keen to encourage as much innovation as possible. This year we are running two classes, Pro and Open class. The only difference is that if you enter the Open Class you are obliged to sell your vehicle for £20,000 at the end of the race, should someone want to buy it. This effetely gives teams in this class a top end budget to work to." Hussein has introduced a number of rules that he hopes will encourage innovation in the future. "Our rules allow for technologies such as multi-traction, which will allow power to more than one wheel. We also allow for regenerative braking and the use of hybrids, and by that we mean more than one power systems." Another interesting rule to be introduced is the ability to change rider configuration. The rider does not have to lean forward and can actually be leaning back with feet forward, similar to the stance of a racing car driver. Although this might have advantages aerodynamically, it can has a trade off with handling, so will be interesting to see what teams decide to do. Although the event is being billed as emission-free racing, this is at point of use. However, the real premise is to speed up the development of lots of alternative technologies with many of the teams hoping to benefit from the innovation and intellectual property that has been developed. The big question is, where are all the manufacturers? Unless, some of them are entering under a pseudonym, the answer from many of the competitors was simply because they would not be able to win it. Despite being interested, in the current financial climate manufacturers do have the money or technology to be able to seriously compete and get the kudos from winning. So, for 2009 at least, the glory will go to academic institutions and grass route innovators.