Please help improve this article or section by expanding it.
Further information might be found on the talk page or at requests for expansion.
Mild hybrids are essentially conventional vehicles with oversized starter motors that also act as generators and electric turbos. The electric generator/motor/starter allows the engine to be turned off whenever the car is coasting, braking, or stopped, yet restart quickly and cleanly. Accessories can continue to run on electrical power while the engine is off, and as in other hybrid designs, the motor is used for regenerative braking to recapture energy. The larger motor is used to spin up the engine to operating rpm speeds before injecting any fuel. It also kicks in anytime there is load on the gas engine, such as a hill or under acceleration.
The downside of early mild hybrids is that the air conditioning suffers in performance when the gasoline engine shuts down, but manufacturers are developing electric air conditioning to solve this problem.