Life cycle assessment of large-scale photovoltaic system and end-of-life policy formulation in Malaysia / Atiqah Hamizah Mohd Nordin

Photovoltaic (PV) system is known as a clean electrification mode considering almost no obvious emissions during its operation. However, when considering its entire life cycle, the PV system still consumes certain amount of primary energy and impacts the environment. Therefore, life cycle assessment (LCA) is used to assess primary energy consumption and environmental impacts of PV systems. Nevertheless, LCA results become unreliable when site-dependent data for appropriate time frame are not considered. In addition, as LCA of different PV module technologies was usually conducted without modifying the inventory of the associated balance-of-system components to meet the specifications of the PV module, the interpretation of results becomes less accurate. In Malaysia, the existing LCA study for large-scale PV system was not conducted using foreground data, thus reducing the representativeness of the results. Moreover, as the number of PV systems is expected to surge in the near future, the PV waste will correspondingly increase, hence presenting a new environmental challenge with the absence of PV end-of-life management policy in Malaysia. Therefore, this study presents the LCA of large-scale PV system and end-of-life policy formulation in Malaysia. The life cycle inventory model of a large-scale PV system in Malaysia was first developed before the primary energy consumption and environmental impacts were quantified. Then, the effect of different PV system configurations on the energy and environmental indicators was evaluated. Later, PV end-of-life policy options were formulated based on life cycle approach. The results showed that the energy payback time and global warming impact of the system are 3.43 years and 30.95 g CO2-eq/kWh respectively, which are 8.74 times and 19 times lower than system lifetime and Malaysian grid emission factor respectively. When comparing different system configurations, the large-scale PV system using cadmium telluride modules provides better energy and environmental indicators compared to crystalline silicon modules. Apart from that, system using central inverters provides better energy and environmental indicators compared to string inverters. Besides that, when comparing PV end-of-life policy options, regulatory approach yields greater benefits than voluntary approach in terms of quantity of recycled PV modules, environment, primary energy consumption and economic implications. In short, this study highlights the energy and environmental hotspots of the large-scale PV system that could provide insights for PV designers and increase awareness among the PV industry and society. Also, the developed policy options shed light on the future impacts and potentials of PV end-of-life management in Malaysia.