In recent years, China has been ambitious in investing and developing renewable energy technologies, aiming to enhance its energy security, mitigate its energy-related CO2 emissions and develop renewable energy industry. The 12th Five Year Plan (2011-2015) has set clear targets on installed capacities of different renewable energy technologies. This study aimed to assess the possible contribution of 12th Five Year Plan for China's future energy system and identify factors that might influence its impacts. First, current status of renewable energy development in China has been reviewed. Then several energy scenarios have been developed in an hourly simulation using an energy system analysis tool EnergyPLAN. It was identified that existing grid bottleneck would greatly reduce the potential contribution of renewable installations in terms of share of renewable electricity generation, share of non-fossil fuels in primary energy and system CO2 emissions. In contrast, improving technical performance of renewable energy technologies and sectoral energy efficiency plays an important role in increasing the share of renewables and promoting China's energy system transition. Finally, some policy suggestions were drawn to facilitate a better implementation of the renewable energy plan. Published by Elsevier Ltd.