How KERS Technology Works In Formula One

There are many aspects to F1 cars that significantly contribute to the overall speed of them. KERS or 'Kinetic Energy Recovery System' is an aspect of Formula One which stores the energy of braking and then uses it when accelerating again. The way the energy can be stored is limited by FIA regulations:

  1. Electrically - This requires huge batteries to store the energy. The batteries usually overheat requiring extra fans to cool them. Overheating batteries is one of the main reasons why KERS fail in F1.
  2. Mechanically - Mechanical energy is stored through a rotating flywheel (spinning up to 80,000 rpm) connected to an electrical motor. As well as not having the problem of overheating, they are usually lighter than batteries. However, due to FIA regulations, weight ballasts are added to the car so no car has any weight advantage for the form of KERS it implements (which is an advantage as teams can choose where they want to put the weight ballasts for the best centre of gravity). Due to the fact the energy stored does not change state, mechanical KERS is far more efficient as there are minimal losses.
  3. Hydraulically - The energy from braking is used to pressurise hydraulic containers which store the energy until required.

The majority of F1 teams use the electrical KERS because it creates instant acceleration with maximum torque unlike the two other versions. The electrical KERS unit uses a motor generator. When braking, the generator creates an alternating current which is rectified to a DC current so that the electrical energy can be stored in a battery below the driver. The process is then reversed back into the engine where the discharge of energy to the KERS unit turns it into a motor which is gear-driven and connected to the front of the engine crankshaft. Magneti Marelli claims the motor generator can provide up to 40,000 RPM which is still only half that of the flywheel.
A flowchart of how electrical KERS works in F1