Alternator/generator input horsepower
Alternator/generator input horsepower means the mechanical horsepower input to the main alternator or generator of a locomotive. For the purpose of calculating brake horsepower, alternator/generator input horsepower does not include any power used to circulate engine coolant, circulate engine lubricant, or to supply fuel to the engine.
40 CFR § 92.2
The definitions of this section apply to this subpart. They also apply to all subparts of this part, except where noted otherwise.