Degradation Science and Pathways in PV Systems

Photovoltaic (PV) energy, with its strong market growth and increased competitiveness against fossil fuels in recent years, is becoming one of the major energy resources available to address our future energy demands. The advancement of energy sciences and technologies requires not only highly efficient products but also sustainable and reliable operation for long service lifetimes. PV modules face harsh environmental conditions during real-world deployment, and investigations into the reliability and degradation of these systems are now emerging. Nevertheless, research interests mostly tend to concentrate on single degradation mechanisms and without exploring the interplay mechanisms and degradation pathways in these complex systems. A more comprehensive approach is therefore required for enhanced PV performance, lifetime, cost, and reliability. Lifetime and degradation science, based on a stressor and response framework, involves quantitative knowledge of material-, component-, and system-level degradation mechanisms, rates, and the degradation pathways that connect mechanisms into sequential steps over lifetime. This chapter will focus on new aspects of, and research directions in, reliability, lifetime performance, and the degradation science of PV systems.