Amirkabir University of Technology Advances in Energy Sciences and Technologies 3115-9117 1 3 2025 12 01 From energy choices to SMR deployment: A system-level comparative assessment of nuclear power (SMRs), fossil fuels, and renewable energy options in Iran 308 316 5968 10.22060/aest.2026.25417.1002 EN Abouzar Kiyani tehran 0009-0000-3455-9660 Naser Mansour Sharifloo tehran Ali Bahrami Samani tehran Journal Article 2025 11 03 Energy planning in countries heavily reliant on fossil fuels demands analytical frameworks that go beyond conventional cost-based comparisons. Iran’s power system—despite its abundant oil and natural gas resources—is increasingly strained by rising electricity demand, seasonal gas supply constraints, aging thermal infrastructure, and growing environmental pressures. In this context, assessing energy technologies not by their standalone generation costs, but by their system-level value, has become critical to ensuring long-term reliability and sustainability.<br />This paper presents a system-level comparative assessment of fossil fuels, renewable energy, and nuclear power—with a specific focus on Small Modular Reactors (SMRs)—to evaluate their potential contributions to Iran’s future energy mix. The analysis integrates technological performance, economic viability, regulatory readiness, and market deployment pathways, emphasizing how each option supports grid stability, fuel security, flexibility, and decarbonization.<br />The findings show that fossil-based generation is losing system value due to supply-side pressures and unpriced environmental costs. Renewables deliver clear emission benefits but are limited by intermittency, grid integration challenges, and dependence on backup capacity. In contrast, SMRs offer a balanced profile: firm low-carbon output, modular and phased investment, enhanced passive safety, and synergy with non-electric applications—particularly nuclear desalination, which aligns with Iran’s water-energy nexus. The study concludes that SMRs can serve as a strategic complement to renewables and a viable transitional option for reducing fossil dependence—provided that enabling regulatory, institutional, and financing conditions are established. https://aest.aut.ac.ir/article_5968_8c97dbeee3b0d40ced7f514b99a93d93.pdf