Racers have been using driveshaft alternators for decades I wonder why all cars don't have them?

    Whether you want to clean up the engine bay, reduce parasitic losses on the engine, or create extra electrical power for accessories -a drive shaft alternator makes sense. Your car will use its own inertia to help charge its batteries.

1. One could put an alternator on the tail shaft of the transmission.

2. A driveshaft alternator could be used along with a traditional alternator.