Alkaline fuel cells are low temperature fuel cells for which stationary applications, e.g. cogeneration in buildings, are a promising market. In order to guarantee a long life, water and thermal management has to be done in a careful way. In order to better understand the water, alkali and thermal flows, a two-dimensional model for an Alkaline Fuel Cell is developed using a control volume approach. In each volume the electrochemical reactions together with the mass and energy balance are solved. The model is created in Aspen Custom Modeller, the development environment of Aspen Plus, where special attention is given to the physical flow of hydrogen, water and air in the system. In this way the developed component, the AFC-cell. can be built into stack configurations to understand its effect on the overall performance. The model is validated by experimental data from measured performance by VITO with their Cell Voltage Monitor at a test case, where the AFC-Unit is used as a cogeneration unit. (C) 2009 Elsevier B.V. All rights reserved.