Le Mans Hybrid Racers, 2012----Carl Schwab

August 1, 2009, the writer prepared a BLOG on the subject of HYBRID racers used in competition at the Le Mans Race. In the WSJ, Friday, June 15, 2012 and article entitled, “Hybrid Take Track at Le Mans” appeared, almost 3 years from the time I wrote the BLOG. Some interesting differences have taken place.

According to the WSJ article the main purpose of the of a Le Mans win is, “bragging rights”. And the competitors spend LOTS of money for promotions. Of the two, Toyota and Audi, Audi has won several times, BUT not with a hybrid. Toyota has NOT won as yet and was set back a bit by the terrible tsunami damage about 2 years ago now.

At the original writing of the first BLOG mention was made that test drivers did not like the feel of how the regenerative braking felt to the driver. At that time, 3 years ago, the hybrid technology was applied to the driving wheels (rear wheels) and that is a major difference now---ICE power is to the rear wheels and the Hybrid drive is to the front wheels. The driving pattern at the Le Mans is quite different from Stop&Go LOCAL driving. It has frequent decelerations/accelerations lasting seconds and at power levels much higher though shorter in duration. Other changes are the Toyota in their entry is using SuperCaps in place of Li-ion batteries and the energy stored and reused is measured in seconds BUT at huge currents.

AN ASIDE—The time scales for Le Mans and for LOCAL Stop&Go are at extreme ends. One is measured in seconds while the other is a few minutes. This sort of frames the technology---the same equations are used to do the calculations, but the methodology drives the technology differences. The Le Mans need stresses POWER while the LOCAL Stop&Go stresses ENERGY. This IS more profound than it at first seems.

ANOTHER ASIDE--- The technology that is evolving for the Le Mans type racing is actually closer to the so-called mild hybrid such as used in the 2012 Buick LaCrosse. Both are stressing fuel economy while driving at high way speeds and higher and ignoring the LOCAL Stop&Go scenario. Very important.

The other hybrid entry is by Audi and instead of SuperCaps they are using flywheel storage. BTW, the equations for energy storage for SuperCaps and flywheel technology are identical and are what used to be referred to as “dualities”. Audi is also applying the ICE to the rear wheels and regenerative braking/re-acceleration to the front wheels. Audi seems more comfortable with flywheel storage technology from past experience. BTW I do recall some 30 years ago that Long Island Railroad experimented with flywheel storage on passenger trains to recover decelerating energy coming into a station and reusing for departure. I recall a claim that the recovered energy could drive the train out of station some 2 miles. Spectacular as it sounds the project never went further because of funding problems.

A Post Script---In the first meeting just passed Audi DID come in first, however the Toyota hybrid became involved in a crash and did not complete the race.  Maybe better luck next time<G>. 

INTERESTING---

Comments

[D2406-LTO3]

I really appreciate your wonderful knowledge and the time you put into educating the rest of us. I think the game should be more and more abundant, thank you.

[Carl Schwab]

To D2406-LT03------------Thanks----------Carl Schwab

[Carl Schwab]

BTW both the Audi and Toyota hybrids finished the race with one set of brake pads i.e. no replacement during the race. I learned that conventional Le Mans racers replace the brake pads at least once during the 24 hour race. Average change time if less than 10 minutes. ---Carl Schwab