A system and method is disclosed for creating and/or maintaining an electrical load on a diesel engine generator for use on a marine vessel in order to avoid the harmful effects of no-load or low-load operation of the diesel engine. The parasitic load bank system 10 utilizes the heat transfer fluid 23 contained in the closed circulation loop 28 of a chille7d-fluid air conditioning system 14 for creating and/or maintaining the electrical load on the diesel engine generator 12 by utilizing a load bank controller 44 for diverting a portion 23c of the heat transfer fluid 23a being supplied to the vessel's air handlers 42 into heat exchange relationship with the heat transfer fluid 20b discharged from the air conditioning system's source of heat transfer 18 such that the heat exchanged heat transfer fluid 23f activates the source of heat transfer 18, which may be a chiller, reverse-cycle chiller or heat pump, to create an electrical power demand on the diesel engine generator 12.