Sorry, NASCAR fans. Probably the most important motorsport event in the world is 24 Hours of Le Mans. It’s the world’s oldest continually-running car race, and somewhat surprisingly this year, four of the top six contenders are hybrid cars.

Above: Audi R18

Two are from perennial all-star team Audi, and two are from a team that’s been absent for a decade: Toyota.

Car technology is often tested and perfected in the racing world. The list of innovations that moved from race cars to street cars is long: rear view mirrors, crumple zones for crash safety, paddle shifters for automatic-like manual transmissions, crash recorders, turbo chargers, seat belts, and more.

That’s why it’s important that hybrid cars are appearing — and performing — in the most demanding automotive conditions imaginable. Technologies developed here are making their way to the daily driver car, and the research and development costs are borne by high-profile racing teams.

Both the Audi and Toyota teams are using regenerative braking systems to achieve the hybrid designation. During hard braking before a turn, the cars capture some of the energy used to decelerate and then apply that energy to the wheels to help the car speed up again after the curve.

Above: Toyota TS030

The Audi hybrid system is partially mechanical: as the R-18 e-Tron hybrid quattro slows, a flywheel spins up, grabbing some of that energy, which is converted into electricity and then applied to electric motors driving the front wheels. The Toyota system is a little different — it stores power in a capacitor and then applies energy to the rear wheels.

Early results for the hybrids have been good: As of hour eight, one of the hybrid Audis is leading, and until a crash caused by another driver, one of the Toyotas was in third place. The other Toyota briefly held the lead until a mechanical issue dropped it into the pits.

Few cars survive Le Mans unscathed. The race is known as the Grand Prix of Endurance and Efficiency for a reason. But it’s encouraging for people who appreciate breathable air that the hybrids are starting and running well.

[ Updated: 5:15 ]

This is the crash that took the first Toyota hybrid out of the race. As you can see, it is in no way the Toyota drivers’ fault:

Image credits: Audi, Toyota, esbobeldijk / Shutterstock.com