Environmental impact and depletion of mineral resources such as coal, oil and gas are prompting a reexamination of an alternative to these resources. A safe and sustainable energy pathway which is crucial to sustainable development in addition to greenhouse gas emitters and its relationship with climate change are leading factors to look for adequate strategies concerning both energy saving and environmental protection. Solar heat engines are attracting much interest nowadays and, as a consequence, different Stirling engine coupled to solar collector have been investigated since it meets the demands of the efficient use of energy and assuring environmental security. In recent years several prototypes and experimental facilities of solar Stirling engine have been developed. The future commercial interest of this alternative for electric power generation relies on a reduction of investment costs and on an increase of performance. The Stirling heat engine was first patented in 1816 by Robert Stirling. Since then, several Stirling engines based on his invention have been built in many forms and sizes. The engine works with a closed cycle and uses several gases as working fluid. Several prototypes have already been studied and produced but the alpha Stirling engine using the Ross Yoke linkage was not well studied although this kind of engine has the advantage of minimizing lateral forces acting on the pistons and leading to a more efficient and compact design compared to beta or gamma Stirling configuration, The objective of this work was the study of the effect of the geometrical and physical parameters on Ross Yoke Stirling engine performance in order to determine the significant thermodynamic parameters having an impact on engine performance. We proposed thermodynamic optimization of a Ross Yoke Stirling engine on the basis of a numerical model integrating the internal and external irreversibility. As a result, this analysis indicated that the performance of a Ross Yoke Stirling cycle engine with air as working gas depends critically on the geometrical parameters and heat input. (C) 2013 Elsevier Ltd. All rights reserved.