TOWARDS LIGHT-WEIGHT AND MECHANICALLY DURABLE PHOTOVOLTAIC MODULES FOR FLOATING APPLICATIONS

Abstract

With the increased demand of energy and the scarcity of the conventional energy sources, renewable energy becomes more necessary. Additionally, more renewable energy is required in order to achieve a 55% reduction of CO2 emission by 2030 1. Photovoltaic (PV) generation systems are the biggest contributor to the growth in renewable energy. However, further growth is limited due to the availability of suitable land. Floating PV is an attractive solution for expanding the capacity potential for renewables. Some other advantages of floating PV installations are that they enable dual use of water reservoirs and that the cooling effect on the PV modules increases their efficiency significantly. Within the project Marine Solar POtential and Technology Study (MarineSPOTS), we study the possible deployment of floating PV at the North Sea, by investigating the energy yield production, the integration to the grid, the durability and the environmental impact of such PV plant. One of the major durability concerns of a floating PV installation is the mechanical load that the PV modules undergo, due to strong winds that might occur at open water and the movement induced by the waves. This study focuses on quantifying the impact of the mentioned stressors. For the achievement of this goal, multiple simulations and experiments for validation are conducted. Initially, the effect of configuration of the PV modules (e.g. inclination and orientation) is examined. Additionally, various thicknesses of PV glass are assumed, for the optimization of the mechanical stability and weight/material consumption. Finally, a dynamic mechanical load test is compared to simulations, in order to estimate the influence of the vibration on the stresses developed within a PV module, due to varied wind speed. Preliminary results show that a low-angle east-west configuration is preferable to a high-angle south configuration from the mechanical perspective and that thinner PV glass with 2 mm thickness (glass-glass structure) may be adequate for offshore PV installations, although its durability needs to be evaluated for dynamic mechanical load due to wind and wave speed variation. Furthermore, a method to compare the mechanical stress occurring within a PV module due to varied wind speed and the stress due to dynamic mechanical load testing is being developed and will be extended to include wave induced vibrations.