Recent progress and future prospects of silicon solar module recycling

Silicon solar modules are only 10-15 wt% circular with today's recycling technologies. A 90 wt% circularity requires that all the inorganic materials in silicon modules be recovered for reuse in solar or similar applications. Major technical barriers to a 90 wt % circularity for silicon modules include: 1) removal of the fluoropolymer back sheet; 2) detachment of silicon cells from glass; 3) removal of the encapsulant on silicon cells; and 4) mild chemistry and minimization of chemical waste along with high material recovery rates. Noticeable progress in recycling technologies in the last few years includes: 1) mechanical milling to remove the fluoropolymer back sheet; 2) laser debonding of the encapsulant from silicon cells; 3) dissolution of the encapsulant with a base; 4) mild chemistry for silver and lead recovery; and 5) regenerative chemistry to reuse some of the chemicals in silicon cell recycling.

Automated summary

Silicon solar modules currently have a recycling rate of only 10-15%, but achieving a 90% circularity rate faces technical barriers such as removing the back sheet, detaching silicon cells, and removing the encapsulant. Significant progress has been made in recycling technologies in recent years, including mechanical milling, laser debonding, and dissolution methods.