PFAS and Solar

Solar panels are one such product that some people have pointed out as a potential source of PFAS pollution.

So, what is PFAS?

PFAS is a group of about 9,000 chemicals with a similar chemical structure. It's important to know that just because they share a chemical structure does not mean that all PFAS chemicals are equally toxic or have the same ability to leach into our environment. More commonly, the term "PFAS" is used to describe a few select chemicals that are commonly used and have been shown to have serious health effects.

Where does PFAS potentially come from with solar panels, and what type of PFAS chemicals might be used?

Solar panels are about 90% glass and aluminum, with the remaining materials being mostly benign, such as silicone and copper. 

The potential parts of a solar panel that could contain PFAS are:

• Back sheet film – The back sheet of a PV panel is a layer on the non-sun-facing side that helps seal the panel against water and moisture infiltration. These back sheets are often composed of fluoropolymers, which are technically PFAS due to their chemical structure but have been documented as a polymer of low concern based on research
  showing their resistance to leaching and negligible risk to health. This makes these compounds unlikely to pose health concerns to residents near a solar site.
• Wiring – Many electronics, including solar panels, use PFAS-containing wire insulation for its heat resistance. This insulation is often of the low-concern type, such as fluoropolymers or Teflon, and is well contained within the multiple layers of protection that solar panels provide for internal components, making leaching unfeasible under normal operating conditions.
• Encapsulants and Sealants – Solar panels often use various encapsulants and sealants to protect the internal components from water and other contaminants. While some sealants in other industries use PFAS compounds (such as carpentry glues and specialty tapes), solar panel producers use silicon-based products or butyl rubber to seal panels. For encapsulants, solar panels rely on Ethylene-Vinyl-Acetate (EVA), the same non-PFAS hydrocarbon-based encapsulant used in car windshields.

Conclusion

While it's true that the evidence currently points to solar panels largely limiting their PFAS use and, when applied, using significantly less concerning types of PFAS compounds, more still needs to be done to determine the risk posed by any particular solar panel.

Sources:

Korzeniowski SH, Buck RC, Newkold RM, Kassmi AE, Laganis E, Matsuoka Y, Dinelli B, Beauchet S, Adamsky F, Weilandt K, Soni VK, Kapoor D, Gunasekar P, Malvasi M, Brinati G, Musio S. A critical review of the application of polymer of low concern regulatory criteria to fluoropolymers II: Fluoroplastics and fluoroelastomers. Integr Environ Assess Manag. 2023 Mar;19(2):326-354. doi: 10.1002/ieam.4646. Epub 2022 Aug 9. PMID: 35678199.

Preeti Nain, Annick Anctil, Per- and polyfluoroalkyl substances (PFAS) in solar photovoltaic modules, Renewable and Sustainable Energy Reviews, Volume 215, 2025, doi.org/10.1016/j.rser.2025.115562.

Nain, P., Anctil, A. Do solar panels contain PFAS?. MRS Energy & Sustainability 13, 224–232 (2026). doi.org/10.1557/s43581-026-00156-7