Understanding degradation across cell, module, and field levels in SHJ and TOPCon technology

Bram Hoex¹, Chandany Sen¹, Muhammad Umair Khan¹, Xinyuan Wu¹, Phillip Hamer¹, Shukla Poddar¹, Haoran Wang¹, Jiexi Fu¹, Ruirui Lv²,  Guangchun Zhang²

¹School of Photovoltaic and Renewable Energy Engineering, UNSW, Australia

² CSI Solar Co. Ltd.

 E-mail: b.hoex@unsw.edu.au

Abstract

In the photovoltaic industry, the emphasis is often almost solely on enhancing solar cell and module efficiency. However, the paramount metric for evaluating technology's economic viability is the levelized cost of electricity (LCOE), which necessitates not only high efficiency but also extended module longevity. Achieving the lowest possible LCOE requires maintaining annual performance degradation rates below 0.5% per year.

This study will discuss the stability of heterojunction and TOPCon solar cells and modules, with a special emphasis on understanding and mitigating corrosion-induced degradation. We introduce advanced accelerated cell testing methodologies that offer rapid assessment—up to a hundredfold faster than conventional module-level testing. This acceleration is crucial for timely insights into degradation mechanisms and their mitigation. Furthermore, we detail our approaches to cell and module-level degradation prevention and present a comprehensive global-scale modelling of selected degradation modes.

Keywords: HJT; TOPCon; LCOE; Degradation; Damp-heat

Biography:

Bram Hoex is a Professor and Deputy Head at UNSW Sydney's School of Photovoltaic and Renewable Energy Engineering. His research focusses on solar cell efficiency improvement, reliability and performance, financial and performance yield modelling, and the application of artificial intelligence for material discovery. He published over 250 papers and has received multiple international awards, including the 2008 SolarWorld Junior Einstein and 2016 IEEE PVSC Young Professional. In 2018, Renewable Energy World featured him on their global "Solar 40 under 40" list.