In this paper the limiting mechanisms in the methanol-steam reformation process are analyzed theoretically and compared experimentally as to determine each contribution and limitation to the overall process. Experimental data from steam reformers are presented and analyzed. Models of each mechanism are provided to quantify theoretical times necessary for each process to occur. While the models in this paper are not precise representations of all steam reforming processes, the models do provide enough evidence to conclude that heat transfer is the dominant limiting mechanism in methanol-steam reformation. Further studies quantifying the experimental effects of heat transfer should be pursued with the ultimate goal of properly sizing steam reformers. (c) 2007 Elsevier B.V. All rights reserved.