Without getting too technical; Generators are basically DC motors with armatures and brushes able to handle allot of current and produce DC (direct current) directly. The current produced by the armature windings is commuted through the carbon brushes which wear faster as the current demand increases (not so efficient). It outputs DC voltage and a regulator is required to maintain voltage output. Spinning this device make some power at any speed.
An Alternator as the name implies makes AC (Alternating Current). To make this energy useful you need a rectifier to convert the sinusoidal AC ouput DC. These can be internal or external. You also need a voltage regulator to control the voltage output.
Unlike the DC generator - an alternator requires a small amount of energy to energize the stator electromagnets before it can produce AC output. Hence the reason a completely dead battery may not get a charging system back to charging just by spinning it. They usually need a 4 to 6 volts but not much current to make a magnetic field which allows the alternator to come on line and produce energy.
Anyway - In this case, the stator spins, small brushes feed it a tiny amount of DC energy and it becomes a spinning magnet. The magnet spins through the field coils which make AC current. Diodes are usually in close proximity to the field coils and convert the AC power into DC. Because the field coils are making the energy, output is not fed through brushes and they are much more efficient than DC generators.
OK - As you were. . . .
Fit your FZ with efficient lighting devices and if grip heaters, heated vests, and added lights are part of your plan. Look at the total wattage and figure you can't run them all at once!