Challenges and strategic assessment of biohydrogen development via a fuzzy Delphi-SWOT-QSPM framework

The increasing dependence on fossil fuels and the resulting climate and air quality challenges underscore the need for low-carbon energy carriers such as hydrogen. Despite its abundant fossil resources, Iran faces growing environmental pressures and emission reduction commitments, necessitating alternatives like biohydrogen. This study provides a comprehensive strategic-environmental assessment of biohydrogen development in Iran by integrating a structured literature review, SWOT analysis, Fuzzy Delphi expert elicitation, Internal and External Factor Evaluation (IFE/EFE), and the Quantitative Strategic Planning Matrix (QSPM). Of a total of 412 records initially identified, 67 articles met the inclusion criteria, which focused on strategic planning in the energy or environmental sectors and explicit reporting of SWOT factors. A panel of 20 experts in energy, environmental biotechnology, and biohydrogen systems validated and refined the environmental factors, resulting in the identification of 17 strengths, 14 weaknesses, 13 opportunities, and 13 threats. QSPM was applied to quantify the relative significance of these factors and prioritize strategic actions. The IFE and EFE scores of 3.57 and 3.03, respectively, position biohydrogen development in an aggressive ST strategic zone, indicating strong internal capacity supported by favorable macro-environmental conditions. QSPM prioritization revealed oxygen-control strategies for nitrogenase and hydrogenase activity as the most attractive option (score = 6.05), followed using low-cost carbon sources or industrial waste streams (5.95) and hybrid biomass-coal technologies (5.74). This framework provides a robust basis for strategic planning and supports policy, investment, and research directions for large-scale biohydrogen deployment.