Fundamental studies on the reaction kinetics of thermal decomposition of bio-composite based backsheet material in photovoltaic (PV) panel

The electricity demand has increased exponentially due to the increase of the world population therefore, solar energy promises a brighter future to continuously generate electricity by utilizing the world’s most abundant resources, i.e., Sun. One of the important components of PV panels is the backsheet which acts as the protective layer from various environmental stressors including high UV radiation, temperature and moisture. One of the challenges faced in the solar industry is the use of non-biodegradable materials which could highly impact the environment during manufacturing and decomposition processes. Thus, the main focus of this study is to replace the commercial backsheet derived from petroleum with a novel bio-composite material comprises vetiver and polylactic acid (PLA). This study will assess the suitability of the bio-composite backsheet in the thermal stability aspect to reduce the use of non-biodegradable materials made from fluoropolymer, i.e., Polyvinyl fluoride, PVF. Vetiver (Chrysopogon Zizanoides) is a tropical plant in which its roots are used for various applications due to its valuable properties, especially the cooling effect. PLA has a good mechanical strength and is environmentally friendly as it can be recycled/reused multiple times with minimal loss of properties. One of the drawbacks of PLA is the low thermal conductivity (or low heat dissipation). Thermal conductivity is important as the backsheet material needs to maintain its temperature after high sunlight exposure in order to keep its optimum performance. Mixing vetiver with PLA could further elevate the mechanical properties and the thermal conductivity of the material. The objective of this study is to evaluate the novel bio-composite thermal behaviour, particularly the reaction kinetics such as the activation energy and reaction order which can be used to predict the service shelf life of the backsheet material. In order to perform this, TGA is a useful method to study the changes of a material in terms of its weight loss by applying a constant rate of heating over time whereas ANSYS is used to study the dielectric properties and compare the simulation results from both PVF and the biocomposite material. Both of these studies will lead to identifying how the PV panel will degrade over time when exposed to heat and its aging properties in terms of the durability of the PV panel. Lastly, the significance of the outcome is to understand the thermal degradation and dielectric properties and perform the simulation study to ensure the PV output performance is in accordance with the standard IEC 61724.