When and How Solar Photovoltaic Waste Would Become a Burden for Hong Kong? and the Actionable Insights for Effective Management

Hong Kong's first solar photovoltaic (PV) installation dates back to 1985 as the power source for weather stations in remote locations. Later a PV system was installed on the remote island of Hei Ling Chau to power the drug addiction treatment center. Following this, with the government's push towards renewables, many small and conventional stand-alone applications-based PV installations and the most advanced installation types, including Building Integrated Photovoltaic (BIPV) on high-rise buildings and Floating Solar Photovltiaics (FSPV) on water reservoirs, have become popular. Recently, environmentalists and other stakeholders' started expressing concerns about aging solar PV panels due to the lack of end-of-life (EoL) regulations specific to solar panels. Given the existing issues with the city's e-waste management and favoring feed-in tariff policy that is taking the solar installations in a fast-paced manner, we aim to investigate 'when and how solar photovoltaic waste would become a burden for Hong Kong with evidence-based, actionable insights for effective management'.

For this, we first applied a data-driven approach for identifying and mapping solar PV installations in and around Hong Kong to estimate the exact time for different installations' aging for further quantification of possible e-waste. Second, the consequences of not having a regulation leading to various environmental risks are estimated.

The results show that many government-owned solar PV installations have already reached EoL 12 years back from the referenced year 2022, and the first installed non-government solar PV installations will reach EoL in the coming two years (i.e., 2024). The observed environmental risks include the metal's leaching potential, cadmium exposure, and potential chances for water contamination. It is also observed that the existing e-waste guidelines of Hong Kong and the type of material recovery units at Hong Kong's eco-park can potentially recover valuable materials from the EoL solar panels if regulation and infrastructure support are provided, thus promoting local recycling. Overall, this study offers an aging timeline for solar panels and secondary material inventory when solar panels are recycled under various methods, suggesting the Hong Kong government take immediate action on formulating EoL regulations for solar panels.