Firms in the power industry are currently facing challenges to maintain competitiveness while maintaining minimal environmental impacts. Responding to the above challenges, environmental management systems (EMSs) are becoming more popular within organizational policies, programs, and operating agendas. Especially in the knowledge-based photovoltaic energy industry, the learning efforts of EMSs can effectively improve technological development, managing efficiency, and firm performance at the same time. However, with rapidly changing technologies along with increasingly complicated environments, how to select a suitable project contractor for EMS has become an important issue that has never been discussed comprehensively. Through the proposed methodology, practitioners can fully understand the expected performance of each EMS contractor under various aspects, and the most appropriate EMS contractor with the best synthesized performance can be selected under the complex and dynamic environment. The methodology shall enable firms to select the most suitable EMS project contractors. ©2016 AIP Publishing LLC.