So! I went to Le Mans again this year for the 24 hour WEC race and now consider it my ‘main holiday’ each year. It combines camping which I’ve done for many years now, and racing which I’ve grown to enjoy over the last 3 years. I’ve never seen myself as a motorsports fan until I first attended Silverstone 3 years ago when I got my first DSLR camera. The only reason I went was to try out the camera, but it wasn’t long before I was hooked!
Although there are several classes of cars that take part in Le Mans, I primarily follow the LMP1 class and support Audi. I’ve supported Audi from the beginning really for one reason – they’re the only car in the race running with a diesel engine. I’ve enjoyed diesel technology for many years and it’s the only type of car I’ve owned. The torque is immense compared to petrol which is one of the things I like from it, and it’s one of the advantages for Audi when racing too.
Unfortunately, Audi were given a performance break when they first entered a diesel engine into the race which has slowly been taken away from them, so like all the other teams they’re having to find a way to extract more performance from it each season. Compared with a few years ago, these cars now use 30% less fuel per lap! This is all thanks to performance and fuelling tweaks, and the hybrid systems.
There are several types of hybrid system in use. Audi use a flywheel recovery system which uses a motor-generator on the wheels to generate electricity. This then powers another motor-generator connected to a flywheel in a vacuum, which spins up to a very high speed to store the energy. When it’s needed, it reverses the process and deploys it back to the wheels. Porsche, Nissan and Toyota use a similar motor-generator system but instead use supercapacitors or lithium batteries. Toyota use supercapacitors and the rest use lithium batteries. Each have their benefits and downfalls, but Audi seems to have found the best balance over the technologies as they’ve always seemed to excel. That is until this year.
There are 4 energy storage classes to go with the hybrid systems too. It’s a measure of energy that can be captured and deployed per lap and it’s split up into 2, 4, 6 and 8 megajoule classes. Interestingly, each of the 4 classes was used this year. Nissan used 2MJ, Audi used 4MJ, Toyota used 6MJ and Porsche used 8MJ. Naturally the higher the capacity used the more weight you have to carry so the balance has to be just right. Some how, Porsche managed to use all 8MJ effectively and their straight line acceleration is immense, meaning they can take on any car after a corner and get past them. Unfortunately for them, Audi can go quicker through the corners and that’s where they were re-taking positions. Those two differences makes the cars quite evenly matched over a full lap. I do wonder however if Audi will opt for the full 8MJ in 2016 or not. Toyota are switching from supercapacitors to lithium batteries because the supercapacitors just don’t cut it now. They were much slower than Audi and Porsche this year and they’ve pretty much written this season off as data collection and testing because they just can’t keep up.
The technologies used in Le Mans is destined for road cars, so to see that they can benefit so much from this tweaking and the hybrid systems just goes to show how much this sort of racing is worth doing. Whilst hybrids may not work too well on the road (depending on the type of driving you do – around town hybrids excel, on motorways they don’t), they work very well for racing where there are frequent amounts of heavy braking and accelerating where the energy can be used.
I congratulate Porsche for their Le Mans win this year, breaking a very long streak of wins for Audi. After their downfalls last year, Porsche came right back with improvements to their reliability and knocked the socks off all the other teams. Audi may have won Le Mans if it wasn’t for a hybrid system issue in one of their cars which caused it to lose its pole position. But in any case, the race was still very close at the end. A series of circumstances for both teams slowed them down in different ways. Audi just happened to suffer a little more.
Maybe next year Audi will bounce back and regain their title at Le Mans. I’m certainly hopeful!
Le Mans Photo Gallery:
http://www.andrewwhyman.com/gallery.php?load=images%2Fgallery%2F2015-06-13%2C%20Le%20Mans%202015/