The proposed innovation is a passive, self-regulating, gravity-independent Advanced Product Water Removal and management (APWR) system for incorporation into Polymer Electrolyte Membrane (PEM) primary fuel cell power plants. Passive water removal is incorporated into each cell of the power plant stack. Only pressure differential is required to manage within the cell and to remove and discharge liquid product water from the power plant. The APWR system eliminates the gas circulator, centrifugal separator, heat exchanger (condenser) and controls that comprise the water management system in the conventional aqueous electrolyte fuel cell power plants now in service It also can simplify the reactant supply system by elimination of fuel and oxidant humidifiers. No rotating or active components or gas circulation are required in the APWR system. APWR is based on PEM technology proven in industrial and automotive applications but not applied to space power plants.