Alternators and generators are electromechanical devices designed to produce electricity by converting a form of mechanical energy into electrical energy. Although they perform essentially the same function, they may differ slightly in design and use.

Alternator:

An alternator is generally associated with the production of alternating current (AC) electricity.
It is composed of a rotating coil of conductive wire (rotor) and a set of fixed coils (stator).
When the rotor is rotated, it generates a magnetic field passing through the fixed coils, which induces an alternating electrical voltage in these coils.
Alternators are commonly used in vehicles, power plants and wind turbines to generate alternating current electricity.
Generator:

A generator, on the other hand, is often associated with the production of direct current (DC) electricity.
It uses a mechanical-to-electricity conversion process that relies on the principle of Faraday's law of electromagnetic induction.
Generators have a switch (or set of diodes) that converts the generated AC voltage to DC voltage by rectifying the current.
Generators are frequently used in backup systems, generator sets, and other applications where DC power is required.
Although alternators typically produce alternating current and generators produce direct current, there are alternating current generators and direct current alternators designed for specific applications. The main difference is the electrical output and how they convert mechanical energy into electricity.

In many cases, generators are also called generators, which can be confusing because the term "generator" can be used to refer to both alternators and generators. The choice between an alternator or generator depends on the specific needs of the application, including the type of electrical current required (alternating or direct) and the power required.

Alternators and Generators for current production, used with wind turbine, water turbine and engine generator