Alternators

Alternators are used in automobiles to charge the battery and to power a car's electric system when its engine is running.  The alternator works with the battery to generate power for the electrical components of a vehicle, like the interior and exterior lights, and the instrument panel. 

Alternators produce AC power through electromagnetism formed through the stator and rotor relationship. There are three major components to an automotive charging system: the battery, the voltage regulator and an alternator. 

Alternators are typically found near the front of the engine and are driven by the crankshaft, which converts the pistons' up-and-down movement into circular movement.  Some early model vehicles used a separate drive belt from the crankshaft pulley to the alternator pulley, but most cars today have a serpentine belt, or one belt that drives all components that rely on crankshaft power. Most alternators are mounted using brackets that bolt to a specific point on the engine. One of the brackets is usually a fixed point, while the other is adjustable to tighten the drive belt.