Investigating the Performance of Solar-Powered Electrocoagulation for Water Treatment in Off-Grid Communities in Northern Nigeria

This study investigates the performance of solar-powered electrocoagulation as a decentralised water treatment technology for off-grid rural communities in Northern Nigeria, targeting the treatment of turbid and fluoride-contaminated groundwater that is common in parts of the North West and North East zones. Electrocoagulation using aluminium or iron electrodes is a well-established treatment process that effectively removes turbidity, fluoride, arsenic, and bacteria in a single unit operation with minimal chemical inputs, and its combination with photovoltaic power offers a compelling appropriate technology for communities without grid electricity or reliable chemical supply chains. A bench-scale electrocoagulation reactor was constructed and its performance evaluated across a matrix of electrode gap, current density, and hydraulic retention time conditions using synthetic groundwater samples calibrated to the turbidity and fluoride concentrations typical of Borno and Katsina State groundwater sources. A pilot-scale unit was subsequently assembled and evaluated over a four-week field trial in a community in Borno State using actual well water. Energy consumption per cubic metre of treated water was quantified under the field trial solar power system. Results show that the optimised electrocoagulation conditions achieve turbidity removal above 95 percent and fluoride reduction from 3.2 to below 1.5 milligrams per litre, meeting WHO guideline values. Aluminium electrodes outperform iron electrodes for fluoride removal. Solar power system sizing for a community-scale unit capable of treating 1,000 litres per day requires a 500-watt panel with 200 ampere-hour battery storage under Borno insolation conditions. Keywords: electrocoagulation, solar-powered water treatment, fluoride removal, off-grid, Northern Nigeria.