Energy plays a vital role in the development and well-being of any country. Finding the right energy projects and investing in them could lead to improving the overall condition of nations. Despite the importance of evaluation of energy projects, several factors complicate this issue. The efficiency of projects, reliability of assessments and uncertainty are some of the major issues in energy project evaluation. To simultaneously address all of these essential issues, this paper presents a new approach in renewable energy project evaluation based on the concepts of data envelopment analysis (DEA) and fuzzy simulation of interval-valued intuitionistic fuzzy sets (IVIFSs). The concept of DEA is developed, and a new approach based on introducing a new simulation method for IVIFSs is presented. Moreover, the approach is the last aggregation that avoids information loss. To illustrate the process of this approach, a case study from the literature is adopted and solved. A sensitivity analysis is carried out, and the results are displayed. (c) 2020 Elsevier Ltd. All rights reserved.