Renewable energy policy analysis in Iraq, Saudi Arabia, and Spain: A multi-dimensional assessment using HOMER and documented system performance data

This study evaluates renewable energy policy conditions and hybrid microgrid system (HMGS) performance in Iraq, Saudi Arabia (KSA), and Spain. It combines HOMER Pro simulations under weak-grid conditions with documented residential solar photovoltaic (SPV) performance data from Spain to provide policy-relevant comparative benchmarking evidence. For Iraq, the optimal configuration (SPV–battery–grid with a load following strategy) achieves a renewable fraction of 65.6% and a levelized cost of electricity of 0.1157$/kWh, while substantially reducing CO 2 emissions. Sensitivity analysis identifies key trade-offs associated with capital cost, renewable penetration targets, and grid reliability, and reveals policy-sensitive thresholds affecting system design and performance. Documented Spanish SPV systems indicate strong economic viability, with payback periods of 6–8 years and annual CO 2 reductions of up to 3682 kg, while relatively low self-consumption ratios highlight the importance of demand-side management and residential storage. The results indicate that renewable deployment in Iraq and KSA depends not only on resource availability, but also on transparent compensation mechanisms, targeted financial incentives, and grid modernization. Overall, the study provides a structured framework for linking policy design with techno-economic outcomes in weak-grid and transition energy contexts, contributing to SDG 7 and SDG 13.