This work deals with the design and off-design performance evaluation of an anodic recirculation system based on ejector technology for solid oxide fuel cell hybrid applications. The analysis presented here has been divided into three parts: (i) ejector design taking into account all the thermodynamic, fluid dynamic and chemical constraints, such as steam to carbon ratio (two ejector geometries have been considered: constant area mixing section, constant pressure mixing section); (ii) stand-alone ejector design and off-design performance analysis; (iii) influence on the whole hybrid system-SOFC, reformer, anode recirculation-design and off-design performance of the ejector primary flow conditions (hybrid system part-load conditions). (C) 2003 Elsevier B.V. All rights reserved.