Evaluation of hybrid renewable systems based on optimal location and bio-potential of constructed wetlands: A case study

Abstract

Mapping optimal locations for establishing constructed wetlands and managing waste are critical challenges in developing environmentally friendly wastewater treatment methods. In this study, the Analytic Network Process (ANP) and Geographic Information System (GIS) were used, based on twelve criteria, including distance from groundwater, ground slope, soil type, distance from faults, surface water, protected areas, land use, population density, proximity to villages, roads, railways, and airports. The waste from these wetlands is utilized as biomass for biogas production, providing energy to nearby rural areas. Techno-economic optimization aims to minimize the Levelized Cost of Energy (LCOE) by leveraging bioresource and solar potential. The ANP analysis revealed that technical and economic factors contributed most significantly (58 %) to site selection, with groundwater distance identified as the most critical ecological criterion (39 %). GIS mapping indicated that 7.4 % of Tehran’s surface is ideal, and 22.1 % is appropriate for wetland establishment, potentially benefiting over 380 rural villages. Energy optimization integrated biogas, solar power, and battery systems, achieving an LCOE of $0.130/kWh at sites with biomass supply potential of over 16 tonnes/day, leading to more than 32 % of biogas generation contribution. Converting excess power into green hydrogen reduced the LCOE to $0.159/kWh and enabled the production of approximately 8 tonnes of hydrogen annually.