undesirably cooling the fuel this also keeps the flange 1304 cooler and makes it easier to change stacks 304 without cutting or welding pipe in certain embodiments the regions beneath the grates 1302 a 1302 b may be filled with an insulating material to maintain a temperature differential between the low temperature zone and the hot zone referring to fig1 a perspective view of one embodiment of a thermally integrated system 1400 comprising a pair of reformers 302 and a pair of fuel cells 304 is illustrated in this embodiment the reformers 302 and fuel cells 304 are housed inside an insulated enclosure 1402 the form of which is indicated by the dotted lines to retain heat within the enclosure 1402 and facilitate heat transfer between the components 302 304 more specifically heat generated by the fuel cells 304 which may include heat generated through electrical resistance and electrochemical reactions may be transferred to the reformers 302 by way of radiation and or convection a heat exchanger 1404 may be provided within the enclosure 1402 to transfer heat from exhaust gases which may include oxygen depleted air as well as some co 2 and water vapor exiting the fuel cell stacks 304 to the incoming reactant streams which may include the feedstock fuel air and steam entering the reformers 302 this may retain heat within the enclosure 1402 to provide additional heat.