Life cycle assessment and SAW-Based ranking of renewable electricity and hydrogen production scenarios for sustainable residential architecture: A case study in kerman, Iran

Abstract

The increasing demand for sustainable energy and the need to reduce environmental pollutants highlight the importance of renewable resources. This study evaluates four scenarios for electricity and hydrogen production in a sustainable residential building in Kerman. Using HOMER software, life cycle assessment, and Simple Additive Weighting (SAW) method, it comprehensively assesses economic and environmental indicators. The criteria include economic cost, water consumption, CO₂ emissions, and social cost of pollutants. Results show that the Photovoltaic panel (PV)-Grid-Reformer scenario has the lowest cost ($168,180), while the PV-Wind Turbine (WT)-Grid-Reformer-Electrolyzer scenario has nearly double the cost. Regarding water consumption, the WT-Grid-Reformer scenario records the lowest value at 22,444,474 L, with the fourth scenario consuming 8.2 % more. Environmentally, the PV-WT-Grid-Reformer scenario achieves the lowest CO₂ emissions (−1,420,200 kg), while the PV-WT-GridReformer-Electrolyzer scenario shows the highest (44,040 kg). The best and worst social costs are -$37,041 (PV-WT-Grid-Reformer scenario) and $1148 (PV-WT-GridReformer-Electrolyzer scenario), respectively. Sensitivity analysis and SAW ranking reveal that the first scenario is optimal in cost-centered conditions, whereas the third scenario ranks first when considering environmental concerns, balanced criteria, and water sensitivity. Overall, integrating solar and wind with a reformer appears ideal for minimizing pollutants and social costs, while the use of electrolyzers, due to their high cost and water demand, is less suitable for arid regions like Kerman. Additionally, a Monte Carlo sensitivity analysis with 5000 iterations confirmed the robustness of the SAW-based ranking, showing that the PV–WT–Grid–Reformer scenario ranked first in over 74.5 % of cases, highlighting its consistent superiority across varying decision-making preferences.