NSG Group has announced the successful completion of a demonstration experiment manufacturing float glass from cover glass recovered from end-of-life photovoltaic (PV) modules.
More than a decade has passed since the large-scale introduction of photovoltaic power generation systems in Japan. As these systems approach the end of their service life, the volume of decommissioned panels is expected to rise sharply after 2030. Establishing technologies that enable proper material separation and closed‑loop recycling has therefore become an increasingly important social priority.
However, PV cover glass has traditionally been difficult to recycle due to its composition, which is designed to enhance module performance, and the strong adhesives used to ensure long-term durability.
For this demonstration, the cover glass was separated and extracted using Tokuyama Corporation‘s Low-Temperature Thermal Decomposition Recycling Technology for Photovoltaic Panels at its demonstration facility in Nanporo Town, Hokkaido.
In February of this year, NSG Group conducted a manufacturing trial at the float furnace of its Chiba Plant in Ichihara, Chiba Prefecture, using the recovered cover glass as part of the raw material mix. The trial assessed product quality and the impact on the manufacturing process. Results confirmed that the recycled material can be utilised under defined conditions, demonstrating the feasibility of horizontal recycling into float glass.
Tokuyama, the supplier of the PV cover glass used in the experiment, possesses one of Japan’s leading technologies for efficiently separating and extracting cover glass from photovoltaic panels at the end of their life cycle. To produce even higher-quality float glass, NSG Group partnered with Tokuyama and utilised this technology.
The practical application of this technology and recycling process promotes the effective use of discarded cover glass, contributing to a circular economy. Additionally, we expect reductions in the mining of natural resources, such as silica sand and soda ash; improved combustion efficiency in melting furnaces through increased cullet use; and overall reductions in CO₂ emissions in float glass manufacturing.
These efforts support the “Vision 2025 for Achieving Carbon Neutrality in the Glass Industry by 2050,” announced by the Flat Glass Manufacturers Association of Japan last December, which aims to build a waste glass recycling system.