In which type of hybrid does the electric motor alone not power the vehicle?

The type of hybrid where the electric motor alone does not power the vehicle is referred to as a series hybrid. In this configuration, the electric motor is used primarily to drive the vehicle, but it relies on a gasoline engine or another auxiliary power source to generate electricity that powers the motor. This means that while the electric motor plays a crucial role in the vehicle's operation, it is not solely responsible for powering the vehicle independently at all times.

In a series hybrid, the gasoline engine does not provide direct mechanical propulsion; instead, it serves as a generator for the electric motor. This setup allows for greater efficiency in certain driving conditions since the engine can operate in its optimal performance range, while the electric motor can provide instant torque and smooth acceleration.

In contrast, other types of hybrids, such as parallel hybrids, allow the electric motor and gasoline engine to work together directly, which enables the vehicle to be powered by either one or the other, or both simultaneously. Full hybrids can drive using just the electric motor, but they also have the option to utilize the gasoline engine when needed. Thus, it is the series hybrid where the electric motor is not capable of powering the vehicle alone; it requires support from the other power source to operate effectively.