In this paper, the design of a miniaturized methanol reformer is considered that can operate in two different modes to produce sufficient hydrogen for generating a net power of 24 W and 72 W. The reformer is modeled as a radial flow packed bed reactor and the Ergun equation is used to model the pressure drop. Simulation studies are conducted to study the effect of steam to methanol ratio, inlet pressure and reactor temperature on the production of hydrogen. It is shown that a volume of 20 ml is required to produce sufficient hydrogen for generating the necessary power if an inlet pressure of 202 kPa and a steam to methanol ratio of 1.5 is used. A temperature of 500 K is required for the lower power application while a temperature of 550 K is required for the higher power application.