Rethinking Methane Dynamics in Wetland Ecosystems under Floating Solar PV: Documented Effects, Mechanisms, Mitigation-Harvesting Strategies, and Design Gaps

Wetlands are recognized as significant natural sources of global methane emissions, contributing substantially to climate forcing through complex biogeochemical and microbial processes. At the same time, Floating Solar Photovoltaic (FSPV) systems are rapidly expanding worldwide due to land scarcity, increasing energy demand, and their perceived favorable trade-offs compared to land-based solar installations. As a result, countries with limited available land increasingly consider wetlands, reservoirs, and other water bodies as strategic sites for FSPV deployment. However, the limited consideration of wetland ecological processes in current FSPV planning and design raises concerns that such installations may unintentionally increase methane emissions and generate adverse environmental impacts rather than delivering net climate benefits.

To examine these issues, the researchers conducted a systematic qualitative literature review of fifty (50) peer-reviewed journal articles published between 2010 and 2025. The researchers applied the Comparative Analysis Framework (CAF) to synthesize and categorize existing studies into four major thematic areas: the effects of FSPV on wetland ecosystems, methane dynamics under FSPV installations, methane mitigation strategies associated with floating solar systems, and integrated research frameworks that explicitly link methane emissions with FSPV deployment. The review reveals that most existing studies focus on lakes and reservoirs, while ecologically sensitive wetlands such as marshes and peatlands remain underrepresented in the literature.

Furthermore, the analysis indicates a lack of empirical data on hydrological alterations, nutrient cycling, methane-specific microbial activity, and biogeochemical processes associated with FSPV installations, as well as limited development of predictive models and validation studies. Current research rarely examines methane emissions through technological assessments and policy-oriented reviews, and most FSPV frameworks fail to incorporate methane reduction strategies. Overall, the synthesis identifies critical thematic gaps and highlights emerging priorities for interdisciplinary research approaches that integrate ecological monitoring, methane control strategies, system-level modeling, and policy development. This review highlights the importance of comprehensive, ecosystem-scale research and holistic modeling frameworks to optimize the benefits of FSPV while mitigating the risks associated with methane emissions in wetland environments.