NOVELTY - High molecular weight direct antifreeze cooled fuel cell for producing electrical energy from a reducing fluid and a process oxidant stream includes a high molecular weight direct antifreeze solution passing through a porous water transport plate for cooling the fuel cell, and including ethylene oxide chains terminated by functional alkyl or hydroxyl groups, alcohols, (methoxy)polyethylene glycols, and/or dimethoxypolyethylene glycols.    USE - The high molecular weight direct antifreeze cooled fuel cell is used for producing electrical energy from a reducing fluid and a process oxidant stream. It is for use in transportation vehicles, portable power plants, or as stationary power plants.    ADVANTAGE - The inventive fuel cell may be operated in sub-freezing conditions by use of a direct antifreeze solution cooling fluid that does not produce any performance decay of the fuel cell, that minimizes free water within the system that may be frozen when the fuel cell is not operated, and that does not require isolating an antifreeze cooling fluid from the cathode and anode electrodes within a sealed coolant system.    DETAILED DESCRIPTION - High molecular weight direct antifreeze cooled fuel cell (10) for producing electrical energy from a reducing fluid and a process oxidant stream comprises an electrolyte secured between an anode catalyst and a cathode catalyst, a porous anode substrate secured in direct fluid communication with the anode catalyst for passing the reducing fluid stream adjacent the anode catalyst and a wetproofed cathode support secured in direct fluid communication with the cathode catalyst for passing the process oxidant stream adjacent the cathode catalyst, a porous water transport plate secured in direct fluid communication with the wetproofed cathode support mechanism, and a high molecular weight direct antifreeze solution passing through the porous water transport plate for cooling the fuel cell. The high molecular weight direct antifreeze solution is ethylene oxide chains terminated by functional alkyl or hydroxyl groups, linear alcohols, branched alcohols, polyethylene glycols, methoxypolyethylene glycols, and/or dimethoxypolyethylene glycols. Each member of the group has a molecular weight of 200-8000 atomic mass unit (AMU).    DESCRIPTION OF DRAWING(S) - The figure is a schematic representation of a high molecular weight direct antifreeze cooled fuel cell.    Fuel cell (10)    Anode flow field (12)    Fuel supply component (14)    Reducing fluid vent (18)    Cathode flow field (20)