A hybrid engine (more accurately, a hybrid powertrain) combines a gasoline or diesel engine with one or more electric motors to power the vehicle. The system automatically decides which power source to use for the best balance of performance and fuel efficiency.

Here’s how it works:

Starting and low-speed driving
-The electric motor powers the car.
-This uses energy stored in the battery, so no fuel is burned during short, low-speed trips.

Normal driving

-The gasoline engine starts when more power is needed or the battery charge is low.
-The engine and electric motor may work together to improve acceleration and efficiency.

Hard acceleration

-Both the engine and electric motor provide power at the same time.
-This gives better performance while using less fuel than a gasoline engine alone.

Cruising

-At steady highway speeds, the gasoline engine usually does most of the work because it is more efficient under these conditions.
-The electric motor may assist when needed.

Braking (Regenerative braking)

-Instead of wasting energy as heat, the electric motor acts as a generator.
-It converts the car’s motion into electricity and stores it in the battery for later use.

Battery charging

The battery is charged by:
-Regenerative braking.
-The gasoline engine (in most standard hybrids).
-An external charger (only in plug-in hybrid vehicles).

Types of hybrid vehicles

-Mild Hybrid: The electric motor only assists the engine; it cannot drive the car by itself.
-Full Hybrid: The car can run on the engine, the electric motor, or both.
-Plug-in Hybrid (PHEV): Has a larger battery that can be charged from an electrical outlet, allowing longer electric-only driving.