The Ericsson engine is an external combustion engine suitable for the use of certain energy sources such as solar energy, biomass and waste gases at high temperature, and thus contributes to the fight against global warming. Its open cycle configuration considered in this study can achieve good performance in low power range, most particularly in micro-cogeneration applications. The dynamic model of this engine which is the purpose of this study, takes into account both the pressure losses and the variation of the thermophysical properties of the working fluid as a function of the temperature in the system. The coded models are implemented on a Matlab/Simulink platform where the start-up dynamics and performance simulations are conducted. The optimal settings of the expansion cylinder valves, as well as the characteristic parameters of the engine are thus determined. In this configuration the engine develops a power output of 1.72 kW and reacts well when subjected to a selected perturbation. (C) 2013 Elsevier Ltd. All rights reserved.