Actions for sustainably scalable multi-terawatt photovoltaics

Global deployment of photovoltaic (PV) systems is entering the multi-terawatt scale. Decisions on efficiency, material selection and recyclability will have increasingly large impacts as the PV industry expands. In this Review, we assess which actions ensure sustainability in the PV industry. A PV system requires two to three orders of magnitude less material compared with fossil fuel electricity over the device’s lifetime; however, adding around half a million square kilometres of module area still creates serious challenges in terms of resource consumption and sustainability. Reducing material demands while incorporating material streams into a circular economy can increase the sustainability of material supply. In the short term, the rapid growth of PV will enable decarbonization of the electricity supply, whereas development of multijunction devices and thin-film technologies such as perovskite or concentrator III-V PV can reduce material and energy demand. End-of-life management for PV modules must be considered at the design stage, as these decisions affect future waste outcomes decades later. Finally, social responsibility is an integral part of sustainability and essential for broad acceptance of PV. Understanding the specific challenges of available options will enable optimum sustainable yield from multi-terawatt-scale PVs.