Analysis of Wave-Structure Interaction of Floating Photovoltaic Modules: Results From Wave Flume Testing on Load Responses Under Regular Waves

Abstract The interest in photovoltaic systems installed on connected floating modules has increased over the recent years. For these floating installations, knowledge of the wave-structure interaction of individual modules and also connected chains of modules is lacking. Thus, it is still challenging to estimate the actual (design) loads and possible energy efficiency losses caused by the dynamics of the floating photovoltaic systems. To address these knowledge gaps and to provide insights into the wave-structure interaction of floating PV support structures, a comprehensive experimental study has been conducted in the 90 m long and 2 m wide wave flume at the Leichtweiß-Institute for Hydraulic Engineering and Water Resources of Technische Universität Braunschweig, Germany. Generic floating photovoltaic modules have been designed and manufactured. Both a single module as well as a chain of multiple module have been tested under various regular wave conditions. Three mass loadings, i.e. surcharges, of the individual modules were investigated. The surface elevation around the modules, the mooring line loads and the interconnection forces between the modules, as well as the motion of the floats have been monitored during the campaign. This paper presents an initial analysis of the experimental results. In particular, a first analysis of the mooring line loads for the single- and multi-module configurations under the varying hydrodynamic load conditions is conducted. The results indicate non-linear behaviour and shedding effects of the mooring line loads; however, further analysis as part of future work is required for a better understanding of the observed effects.