A PRISMA-Guided Systematic Review of Floating Photovoltaic Systems for Water and Wastewater Infrastructure

Introduction: Water and wastewater infrastructure requires a continuous electricity supply for pumping, wastewater transport, aeration, monitoring and auxiliary technological processes. Many facilities also include reservoirs, retention basins, treatment ponds and other technical water bodies that may provide suitable surfaces for floating photovoltaic systems. Although floating photovoltaics are increasingly recognised as a land-saving renewable energy solution, their potential application in water and wastewater infrastructure has not yet been systematically evaluated. This study presents a systematic review of floating photovoltaic applications in this sector.

Methods: The systematic review was conducted in accordance with the PRISMA guidelines. Scopus, Web of Science and Google Scholar were systematically searched for publications available up to June 2026. The search strategy combined predefined terms related to floating photovoltaics, floating solar, water reservoirs, wastewater treatment plants, renewable energy integration, evaporation reduction and energy resilience. Records were screened based on their titles, abstracts and full texts. Duplicate and irrelevant publications were removed using predefined inclusion and exclusion criteria. Eligible studies were classified according to water body type, infrastructure application, energy-related benefits, environmental and water-quality aspects, and implementation constraints.

Results: Floating photovoltaic systems were primarily investigated for artificial and technical water bodies, including retention reservoirs, irrigation ponds, raw-water reservoirs, technological reservoirs and wastewater treatment ponds. Reported benefits included local renewable electricity generation, reduced grid dependence, lower indirect carbon dioxide emissions, limited land-use conflicts and potential evaporation reduction. The main constraints concerned anchoring, electrical safety, maintenance access, water-quality impacts, ecological effects, wind exposure, fluctuating water levels and ice conditions.

Conclusion: Floating photovoltaic systems may enhance the sustainability and energy resilience of water and wastewater infrastructure, particularly where technical water bodies coexist with high local electricity demand. Further research should incorporate actual load profiles, technical sizing, long-term environmental monitoring and site-specific implementation guidelines.