Delineating suitable zones for solar-based groundwater exploitation using multi-criteria analysis: A techno-economic assessment for meeting sustainable development goals (SDGs)

Abstract

While several articles have focused on determining a suitability map for groundwater exploitation by assigning weights to different thematic layers, this technique suffers from a lack of worldwide application because it focuses on the features of a specific region (terrain features, vegetation, and climate) during the investigation. To overcome this drawback, we expanded the evaluation method of groundwater exploitation by integrating the region characteristics and topography with the three pillars of sustainability outlined by the SDGs agenda. Seven thematic layers, reflecting the economic and technical characteristics of El-Saloum depression, Egypt, were prepared to develop a solar energy-based groundwater suitability map. It was depicted that about 11.5%, 29.3%, and 44.0% of the total depression were classified into “Most’, “Moderate”, and “Marginal” suitable locations, respectively. Based on the sensitivity analysis, the southeastern zone of the depression emerged as the most suitable site for solar-groundwater utilization due to its low salinity (<5000 ppm), reasonable groundwater depths (less than 50 m), and land availability (undeveloped regions). Substituting a diesel power system (DPS) with a photovoltaic system (PVS) in groundwater pumping and/or reverse osmosis (RO) desalination would reduce 1.2 kg CO2/kWh and maintain a payback period of 6.4 years with a cost of energy (COE) of ∼0.25 US$/kWh. Applying PVS for groundwater management could fulfill about 25.0%, 37.5%, 40.0%, and 20.0% of sustainable development goals (SDGs) 2 “Zero hunger”, 6 “Clean water and sanitation”, 7 “Affordable and clean energy”, 13 “Climate action”. The achievement of these SDGs was equivalent to 22.7%, 15.4%, and 13.2% of the environmental, economic, and social pillars of sustainability, respectively. Consequently, the study's findings are crucial for stakeholders and policymakers involved in the sustainable management of groundwater resources within the SDGs umbrella.