A work machine includes a primary power unit having a rated primary output. The primary power unit is couplable with at least one primary load, including a propulsion load. An auxiliary power unit is mechanically independent from the primary power unit, and has a rated auxiliary output which is smaller than the primary output. The auxiliary power unit is couplable with at least one external load, including an operator initiated load. At least one electrical processing circuit is configured for selectively coupling the primary power unit with one or more primary loads, and for selectively coupling the auxiliary power unit with one or more external loads.