Once the car battery is completely charged, where does the extra output from a car’s alternator go?

Question

I realize there are sophisticated computer controls in today’s automobiles, so let’s keep it simple and use an old Jeep CJ as an example. The thing sometimes powers the lights, wipers, water pumps, radio and charges the battery, but once the battery is completely charged, and all those accessories are turned off, the alternator is still churning out the same output. Where does it go?

In: 4

Answer 1

The alternator only outputs current if the battery voltage is below the “fully charged” threshold. When the battery is charged is simply stops outputting current, which also means it’s not putting load on the engine anymore.