A system, comprising: an enclosure (12, 220, 320, 340, 360) from an ambient environment, including: a generator compartment (14, 144, 514, 544, 644) including a first inlet region and a first outlet region in fluid communication with the ambient environment; an engine compartment (16, 116, 516, 616) including a second inlet region in fluid communication with the generator compartment (14, 144, 514, 544, 644) and a second outlet region in fluid communication with the ambient environment; and a bulkhead between the generator and engine compartments (14, 16, 116, 516, 616) to at least substantially fluidly separate the generator and engine compartments (14, 16, 116, 516, 616); a radiator (28, 528, 628) in the generator compartment (14, 144, 514, 544, 644), wherein a pressurized gas in the generator compartment (14, 144, 514, 544, 644) flows along a first gas flow path through the radiator (28, 528, 628) and out of the generator compartment (14, 144, 514, 544, 644) through the first outlet region; a generator at least partially in the generator compartment (14, 144, 514, 544, 644), the generator having a second gas flow path through the generator and the bulkhead including a generator inlet region opening into the generator compartment (14, 144, 514, 544, 644) and a generator outlet region in fluid communication with the second inlet region; an engine in the engine compartment (16, 116, 516, 616), the engine coupled to the radiator (28, 528, 628) for cooling and coupled to the generator to drive the generator; wherein the generator compartment (14, 144, 514, 544, 644) and the engine compartment (16, 116, 516, 616) are horizontally spaced from one another, the radiator (28, 528, 628) is arranged above the generator in a top portion of the generator compartment (14, 144, 514, 544, 644); and an exhaust aftertreatment system (46, 146, 546, 646) coupled to the engine to clean combustion gases exiting the engine, the exhaust aftertreatment system (46, 146, 546, 646) being arranged above the engine compartment (16, 116, 516, 616). an enclosure (12, 220, 320, 340, 360) from an ambient environment, including: a generator compartment (14, 144, 514, 544, 644) including a first inlet region and a first outlet region in fluid communication with the ambient environment; an engine compartment (16, 116, 516, 616) including a second inlet region in fluid communication with the generator compartment (14, 144, 514, 544, 644) and a second outlet region in fluid communication with the ambient environment; and a bulkhead between the generator and engine compartments (14, 16, 116, 516, 616) to at least substantially fluidly separate the generator and engine compartments (14, 16, 116, 516, 616); a generator compartment (14, 144, 514, 544, 644) including a first inlet region and a first outlet region in fluid communication with the ambient environment; an engine compartment (16, 116, 516, 616) including a second inlet region in fluid communication with the generator compartment (14, 144, 514, 544, 644) and a second outlet region in fluid communication with the ambient environment; and a bulkhead between the generator and engine compartments (14, 16, 116, 516, 616) to at least substantially fluidly separate the generator and engine compartments (14, 16, 116, 516, 616); a radiator (28, 528, 628) in the generator compartment (14, 144, 514, 544, 644), wherein a pressurized gas in the generator compartment (14, 144, 514, 544, 644) flows along a first gas flow path through the radiator (28, 528, 628) and out of the generator compartment (14, 144, 514, 544, 644) through the first outlet region; a generator at least partially in the generator compartment (14, 144, 514, 544, 644), the generator having a second gas flow path through the generator and the bulkhead including a generator inlet region opening into the generator compartment (14, 144, 514, 544, 644) and a generator outlet region in fluid communication with the second inlet region; an engine in the engine compartment (16, 116, 516, 616), the engine coupled to the radiator (28, 528, 628) for cooling and coupled to the generator to drive the generator; wherein the generator compartment (14, 144, 514, 544, 644) and the engine compartment (16, 116, 516, 616) are horizontally spaced from one another, the radiator (28, 528, 628) is arranged above the generator in a top portion of the generator compartment (14, 144, 514, 544, 644); and an exhaust aftertreatment system (46, 146, 546, 646) coupled to the engine to clean combustion gases exiting the engine, the exhaust aftertreatment system (46, 146, 546, 646) being arranged above the engine compartment (16, 116, 516, 616).