ERS (Energy Recovery System)

The Energy Recovery System (ERS) is the hybrid component of the Formula 1 power unit introduced in 2014. It comprises two motor generator units: the MGU-K (Motor Generator Unit - Kinetic) and the MGU-H (Motor Generator Unit - Heat). The MGU-K recovers kinetic energy under braking and deploys it as additional power — up to 120 kW (160 HP) for up to 33.3 seconds per lap. The MGU-H recovers energy from the exhaust gases passing through the turbocharger and can either store it in the battery or use it to spin the turbocharger faster (eliminating turbo lag). Together, the ERS components add approximately 160 HP to the internal combustion engine's output, bringing total power unit output to over 1,000 HP. The MGU-H is being removed from the 2026 regulations due to its complexity and cost.

ERS replaced KERS in 2014 when the new hybrid power unit regulations were introduced. The system was significantly more complex and powerful than KERS. Mercedes developed the most effective ERS in the early hybrid era, contributing significantly to their dominance from 2014 to 2020.