Emerging Trend in Life Cycle Assessment of Various Photo-voltaic Systems

Abstract

This paper seeks to study the sustainability and environmental well-being of PV-based electricity generation systems by performing a thorough case study of life cycle assessment (LCA) of solar PV based electricity generation systems. Life-cycle analysis is an useful tool for examining the environmental characteristics of a product or technology from its origin to de-commissioning. Mass and energy flow over the complete production process starting from silica extraction to the final panel assembling has been observed. Life cycle assessment (LCA) studies of five common photovoltaic (PV) technologies, i.e., mono-crystalline (mono-Si), multi-crystalline (multi-Si), amorphous silicon (a-Si), CdTe thin film (CdTe) and CIS thin film (CIS) are presented in this work. The results depicts that, among the five common PV systems, the CdTe PV system presents the best environmental performance with reference to energy payback time (EPBT) and greenhouse gases (GHG) emission rate due to its low life-cycle energy needs and relatively high conversion efficiency. Meanwhile, the mono-Si PV system depicts the worst because of its high energy intensity during the solar cells manufacturing process. The LCA result shows that PV technologies are already justified to be very sustainable and environmental-friendly. With the emerging of new manufacturing technologies, the environmental robustness of PV technologies is assumed to be further enhanced in the near future.