Synergy of circular economy and blockchain in the renewable energy supply chain: A comparative decision-making framework under uncertainty

• Integrating Circular Economy (CE) and blockchain in renewable energy supply chain. • Prioritizing solutions of blockchain and CE in renewable energy supply chains. • Proposing a hybrid decision framework using F-SWARA and F-MARCOS methods. • Offering robust evaluation using comparative analysis of decision-making methods. • Introducing a real case to use blockchain and CE in Iran’s renewable energy sector. The transition to Renewable Energy (RE) is essential due to environmental challenges and rising demand for energy. Integrating the Circular Economy (CE) and blockchain can enhance Renewable Energy Supply Chain (RESC) performance. In this study, to improve the efficiency of the RE, an integrated decision framework under uncertainty is proposed for the integration of CE and blockchain in the RESC. In the presented framework, using the Fuzzy Stepwise Weight Assessment Ratio Analysis (F-SWARA) and Fuzzy Measurement Alternatives and Ranking according to the COmpromise Solution (F-MARCOS) techniques to assess solutions is suggested. The findings are also assessed for sensitivity in various scenarios and validated using other decision-making techniques. The most significant sub-criteria were the appropriate investment return rate, attention to the suitable investment cost, and improving productivity, with values of 0.228, 0.167, and 0.160. The results specified that tracking and enhancing visibility and reducing overall costs across the entire SC, addressing data security and privacy concerns with its tamper‑resistant cryptographic capabilities, and leveraging this technology to monitor resource usage and assess environmental impacts in support of CE principles were identified as the most suitable solutions.