Utilizing renewable energy (RE) to minimize the use of fossil fuels is an emerging concept throughout the globe to attain energy sufficiency while reducing the negative impact on the environment. Since the existing infrastructures and concepts of energy consumption stand on burning fossil fuels for hundreds of years, ideas for replacing those by implementing RE often stumble with several barriers, especially in developing countries where there are numerous resource constraints. These barriers create critical policymaking challenges to achieving comprehensive energy sustainability. Several studies discovered the challenges to utilizing RE in the context of developing nations. However, no study has yet been conducted to prioritize the challenges and examine the relations among them. This study, thereby, utilizes the decision-making trial, and evaluation laboratory (DEMATEL) method to identify the prioritization, and examine the relations among the critical challenges to utilizing RE in the context of developing countries. Thirteen challenges were identified from reviewing literature and expert feedback, which were then analyzed by the DEMATEL method. The findings revealed that ‘Large land requirement’, ‘Uncertain supply’, and ‘End life management difficulties’ are the three most prominent challenges to utilizing RE in developing countries. The explored cause-effect relations among the challenges indicate ‘Long economic recovery periods’ to be the most causative and ‘Lack of social awareness and acceptance’ to be the least causative challenge. This study is expected to assist the policymakers of developing nations in successfully utilizing RE sources to achieve long-term energy sustainability, thus achieving sustainable development goals (SDGs).