The purpose of this study is to investigate and analyse the technological transition of a new clean energy technology in the market. The agent-based modeling is used in national innovation chain to describe knowledge spillover between main actors in innovation procedure in order to attain renewable energy technology (RET) from basic research to commercial stage. Government’s expenditure on training human resource and R&D activities is modeled as a tool to analyse the development of innovation chain in order to increase diffusion rate of the new technology. Application of the knowledge flow model is demonstrated through analysis of introduction of solar PV in the energy system of Iran and...