4 which is non reactive at the operating temperatures of a proton exchange membrane pem fuel cell this relatively pure hydrogen exit stream 119 for example can be sent directly to a pem fuel cell for power generation the pem fuel cell consumes the hydrogen to generate power and the ch 4 and other non reactive species will build up concentration in the dead headed flow path periodically a valve will open forcing the collected ch 4 and other non reactive species out of the fuel cell to maintain performance while achieve 99 hydrogen utilization in the fuel cell fig2 illustrates a second embodiment 200 of the system in accordance with the present disclosure in this embodiment 200 like numbers are used as in fig1 for the same components embodiment 200 differs specifically from system 100 in that exhaust gas 120 from the reformer 102 feeds directly into and through the heat exchanger surface 132 rather than the discharge of the wgs 103 feeding the heat exchanger 132 thus the thermal energy used to maintain the temperature of the methanation reactor 106 is energy from the exhaust gas 120 from the combustion section of the reformer 102 since this temperature source is used the reformate stream 214 from the wgs 103 flows directly into the condenser 104 the combustion exhaust 120 from the reformer.