Formula 1 is not going hybrid, but it is adding regenerative braking — without the Prius-like batteries and electric motors:
The KERS [Kinetic Energy Recovery System] is basically an efficient CVT [Continuously Variable Transmission] gearbox joined to a flywheel that rotates when the cars undergo braking. The stored energy can then be used to boost acceleration for overtaking and cornering, and will work like the power-boost button seen in the A1GP.
The variator-flywheel solution is being developed by a partnership of two companies, Torotrak and Xtrac:
Torotrak and Xtrac believe that the variator-flywheel solution provides a significantly more compact, efficient, lighter and environmentally-friendly solution than the traditional alternative of electrical-battery systems.
“The variator weighs less than 5kg in these applications and provides a high level of mechanical efficiency, enabling the overall mass of the mechanical KERS systems to be minimised,” says Chris Greenwood, technology director at Torotrak. “This mechanical efficiency, combined with the variator’s ability to change ratio very rapidly, helps to optimise flywheel performance.”
The two companies consider that the system is applicable to other motor sports and everyday vehicles and see the potential for wider applications — particularly on high-performance road cars — as an aid to performance and also as a means of developing future vehicles with reduced CO 2 emission levels.
The system supports the current trend in powertrain design for engine downsizing by providing a means of boosting acceleration, overall performance and economy independently of the vehicle’s engine and without the need for complex electrical-battery hybrid architectures.
A CVT-controlled flywheel is particularly suited to stop-start driving situations when real-world fuel economy is often at its worst. In these conditions, the variator-flywheel system can assist the launch of a vehicle which has slowed down or come to a standstill, by utilising the kinetic energy stored in the flywheel. In heavily congested traffic, where a car is frequently stopped and restarted, the system can help alleviate the heavy fuel consumption and emissions of greenhouse gasses normally associated with these conditions.
For the F1 applications, the stored kinetic energy can be applied by the driver on demand whenever required — at a rate and for a time period set by the regulations — to boost performance for rapid acceleration. The device is particularly beneficial when exiting corners or for tricky overtaking manoeuvres.