An agricultural combine, comprising: a primary power unit having a rated primary output, said primary power unit being a primary internal combustion engine; an auxiliary power unit which is mechanically independent from said primary power unit, said auxiliary power unit being couplable with an external load; and at least one electrical processing circuit configured for selectively coupling said auxiliary power unit with said external load, the electrical processing unit including a vehicle control unit controlling operation of an auxiliary load, wherein said external load corresponds to a parasitic load and the auxiliary load, said parasitic load is a non-drivetrain load without operator intervention, and said auxiliary load is a non-drivetrain load with operator intervention and corresponds to at least one of a heating and air conditioning system; a reel drive; a cleaning shoe drive; an air compressor for cleanout function; a vehicle lighting system; a clean grain unloading system; a cleaning fan drive; a cutterbar/auger drive; a chaff spreader; a clean grain elevator; an auxiliary electrical power outlet; and a hydraulic load placed on said auxiliary power unit; wherein the primary power unit is couplable with at least one primary load that comprises a propulsion load driven via a primary drive train including a transmission, and wherein said electrical processing circuit is configured for selectively coupling said primary power unit with said primary load and includes a transmission control unit, said TCU controlling operation of said transmission, characterized in that said auxiliary power unit is an auxiliary IC engine and has a rated auxiliary output which is smaller than said rated primary output, and said transmission is an infinitely variable transmission. a primary power unit having a rated primary output, said primary power unit being a primary internal combustion engine; an auxiliary power unit which is mechanically independent from said primary power unit, said auxiliary power unit being couplable with an external load; and at least one electrical processing circuit configured for selectively coupling said auxiliary power unit with said external load, the electrical processing unit including a vehicle control unit controlling operation of an auxiliary load, wherein said external load corresponds to a parasitic load and the auxiliary load, said parasitic load is a non-drivetrain load without operator intervention, and said auxiliary load is a non-drivetrain load with operator intervention and corresponds to at least one of a heating and air conditioning system; a reel drive; a cleaning shoe drive; an air compressor for cleanout function; a vehicle lighting system; a clean grain unloading system; a cleaning fan drive; a cutterbar/auger drive; a chaff spreader; a clean grain elevator; an auxiliary electrical power outlet; and a hydraulic load placed on said auxiliary power unit; wherein the primary power unit is couplable with at least one primary load that comprises a propulsion load driven via a primary drive train including a transmission, and wherein said electrical processing circuit is configured for selectively coupling said primary power unit with said primary load and includes a transmission control unit, said TCU controlling operation of said transmission, characterized in that said auxiliary power unit is an auxiliary IC engine and has a rated auxiliary output which is smaller than said rated primary output, and said transmission is an infinitely variable transmission.