This paper focuses on energy system development of the three largest Association of South East Asian Nations (ASEAN) countries: Indonesia, Philippines and Vietnam. The energy infrastructures in these counties are in the process of rapid development and, therefore, technology choices are critical. Applying the energy system model MARKAL and scenario analysis, this paper examines and quantifies the role of clean and advanced energy technologies for efficient local resource exploitation and improving energy security and environmental conditions. The main focus is on the power sector and the paper also addresses the potential ASEAN markets for European energy technologies. The paper concludes that there is a large potential market for clean and advanced energy technologies in the studied countries. If adopted, these technologies will bring several benefits like reduction in primary energy requirement, reduced investments requirement in the power sector and other parts of the energy infrastructure, reduced import of primary energy, reduced CO2 emissions and local pollution, reduced energy system costs and marginal cost of electricity supply. Finally, barriers for transfer and diffusion of advanced energy technologies are discussed. (C) 2009 Elsevier Ltd. All rights reserved.