Design and Evaluation of a Solar-Powered Water Purification System

Thesis Abstract

Access to clean and safe drinking water remains a critical challenge in many rural and semi-urban communities, where conventional water purification infrastructure is often unavailable or unreliable. As the global demand for sustainable and cost-effective water treatment solutions intensifies, solar-powered water purification systems emerge as a promising alternative that leverages renewable energy sources to address water scarcity and contamination issues. This study aims to design, develop, and evaluate a solar-powered water purification system that combines filtration, UV disinfection, and solar thermal technologies to produce potable water from contaminated sources. The specific objectives include analyzing the system's efficiency in removing common waterborne contaminants, assessing its operational sustainability under diverse climatic conditions, and evaluating user acceptability and operational costs. Employing a mixed-methods research design, the study integrates quantitative experimental evaluation with qualitative usability assessments. The quantitative component involved creating a prototype system featuring photovoltaic panels, a multi-stage filtration unit, and ultraviolet (UV) sterilization components. The system was installed and tested over a six-month period in a rural community with an average population of 1,200 residents. Water samples from different sources—surface water, boreholes, and ponds—were collected bi-weekly, with a total of 144 samples analyzed for key parameters such as microbial load (total coliforms and Escherichia coli), turbidity, heavy metals, and chemical contaminants. Analytical techniques such as spectrophotometry, microbial culturing, and atomic absorption spectroscopy were employed. To evaluate the system's efficacy, statistical analyses including paired t-tests, regression analysis, and Analysis of Variance (ANOVA) were performed to compare contaminant levels before and after treatment under varying operational conditions. The qualitative component involved semi-structured interviews and focus group discussions with 50 community members, local health workers, and system operators to assess usability, maintenance challenges, and perceived benefits. Thematic analysis was employed to interpret qualitative data, providing insights into social acceptability and operational sustainability. The expected findings demonstrate that the solar-powered system can consistently reduce microbial pathogen presence by over 99%, significantly lower turbidity levels, and effectively remove heavy metals and chemical pollutants within the permissible limits set by WHO standards. The analysis anticipates identifying the system's optimal operational parameters, such as solar insolation thresholds and maintenance schedules, that maximize purification efficiency. Further, the study expects to find high community acceptance tied to the system’s reliability, ease of use, and cost-effectiveness, alongside a clear reduction in per-unit water treatment costs compared to conventional methods. This research contributes to the growing body of knowledge on sustainable water treatment technologies by providing an integrated design framework and empirical evidence of operational performance for solar-powered purification systems in rural contexts. It advances theoretical understanding by applying the Diffusion of Innovation theory to assess user adoption, as well as the Technological Acceptance Model to evaluate perceived ease of use and usefulness. The findings offer practical guidance for policymakers, engineers, and development agencies involved in water resource management and renewable energy deployment. In conclusion, the study affirms that appropriately designed solar-powered water purification systems can serve as a viable, sustainable solution to water quality challenges in resource-constrained settings. Recommendations include scaling up the prototype deployment, optimizing system components for varied climatic zones, and establishing community-based maintenance models to ensure long-term sustainability. Future research should explore integration with decentralized energy systems, economic feasibility studies, and the development of smart monitoring technologies to further enhance system performance and community resilience.