Beam emitters use removable USB rechargeable battery packs, good for 55 to 60 hours per charge. That is several race days, but the failure mode is always the same: nobody charged them and the pack dies mid-round. Keep a second set charged and swap rather than waiting.
Safety lights and displays take 10 to 14VDC, or mains through an adapter. A 6750 draws about 1.2A, a 6752 about 2.3A. If you are running lights off a battery at a corner with no power, size the battery for the whole day plus margin, and check it between events rather than during one.
Consoles run from 12VDC, 110VAC or 230VAC.
If you have a lot of battery packs, the desktop charger takes eight at once and charges each independently, so one flat pack does not slow the others down.