Environmental and Economic Assessment of a Solar-Powered UF-RO Brackish-Groundwater Desalination System for Irrigation in the Jordan Valley

Water scarcity and groundwater salinization constrain irrigated agriculture in the Jordan Valley. This study evaluates a small-scale photovoltaic-powered brackish-water reverse osmosis (RO) desalination system successively upgraded from single-stage to two-stage RO operation and enhanced with ultrafiltration (UF) pre-treatment. The novelty of the study lies in the integrated assessment of these successive system configurations using field-based operational data. A screening gate-to-gate life-cycle assessment (LCA) and levelized cost of water (LCOW) analysis were performed for a functional unit of 1 m3 of irrigation-quality permeate. Three successive configurations were compared: (i) the baseline single-stage RO system, (ii) a two-stage RO system in which the first-stage concentrate was re-pressurized and treated in a second RO stage, and (iii) a UF-assisted two-stage RO system operated at up to 80% recovery. The configurations were compared using project inventory data for feedwater quality, recovery rate, energy demand, chemical consumption, materials and capital costs. The estimated climate-change impact of the UF-assisted PV-RO configuration was 0.9–1.4 kg CO2-eq/m3. This impact is comparatively low for brackish-water RO and reflects the use of PV electricity, although direct comparison with the literature values is limited by differences in LCA boundaries and assumptions. Recovery increased from 35% for single-stage RO to 60% for two-stage RO and 80% for UF-assisted two-stage RO, reducing brine generation from 1.86 to 0.25 m3/m3 permeate. Economically, increasing RO membrane capacity reduced LCOW from 1.28 to 0.86 JD/m3, whereas the UF-RO configuration increased LCOW to 1.40 JD/m3 because of added capital cost. The results indicate that high recovery and solar power can improve environmental performance, but UF adoption should be justified by reliability, water-quality and membrane-lifetime benefits.