AGC and NPC launch scheme to turn old solar panels into new building glass

Glass manufacturer AGC Inc. has started a collaboration with NPC Incorporated to expand the horizontal recycling of solar panel cover glass, establishing a new scheme to transform waste into architectural glass.

Japan will soon see a large volume of solar panels expected to be decommissioned from the late 2030s. With a typical lifespan of 20 to 30 years, early-generation solar panels are nearing their end of life. Projections indicate that Japan will face hundreds of thousands of tonnes of solar panel waste annually in the coming decade. While recycling is critical for a circular economy, separating the cover glass from other components to achieve the quality needed for reuse has presented significant technical and economic hurdles.

The new partnership leverages specialised equipment developed by NPC. The system uses a patented Hot Knife Separation Method® to separate the glass from the panel’s cell sheet without breakage, followed by a Brush Scraping Method™ to remove residual adhesive materials. AGC has confirmed that this two-step process cleans the recovered glass to its stringent quality standards, making it suitable as a raw material. This creates a viable commercial loop where recycling operators can install NPC’s equipment, process end-of-life panels, and sell the high-quality glass cullet to AGC. As part of the collaboration, AGC provided advice on equipment specifications and is helping to develop the logistics network for efficient cullet collection.

A successful trial of the process was completed in September 2025. Twenty tonnes of cullet produced using NPC’s technology were used as a raw material in the manufacturing of architectural patterned glass at the AGC Yokohama Technical Center. This achievement establishes a new, practical method for the horizontal recycling of solar panel cover glass, complementing existing thermal decomposition and high-pressure water jet techniques.

AGC aims to scale up the programme to recycle several thousand tonnes of solar panel cover glass annually by 2030, accelerating its collaboration with NPC to promote this circular model both in Japan and internationally.