Life cycle materials and water management for CdTe photovoltaics

Abstract

An overview of the current status of CdTe solar cells and modules with respect to life cycle management of raw materials is provided. Actively managing raw materials throughout the product life cycle can help to manage cost and conserve resources for large-scale PV deployment. Among the various materials management strategies, a primary factor influencing the material intensity of PV systems is module conversion efficiency. CdTe record solar cell and module efficiency has recently increased to 19.6% and 16.1%, respectively. Future projections include improving CdTe solar cell efficiency to 22% as well as achieving an average CdTe production line module efficiency of 17% by 2017. Material and energy usage across life cycle stages (module manufacturing, balance of systems, collection and recycling) have been documented in life cycle inventories. An example of life cycle materials management is water management, where specific strategies include minimizing electricity use in PV module manufacturing, improving PV module efficiency, deploying tracking systems, developing a water balance for PV manufacturing facilities, minimizing grading during construction, using dry brush cleaning methods during operation, and recycling end-of-life systems. Due to low life cycle water usage, solar PV provides a potential path forward for addressing the energy–water nexus with solar desalination as an example application, such as the CdTe PV Greenough River Solar Farm in Western Australia.