Toxicity Testing Database for Photovoltaic Modules

• Published in: Conference record of the IEEE Photovoltaic Specialists Conference p. 1026
• Main Authors: Li, Fang, Tatapudi, Sai Ravi, Shaw, Stephanie, Libby, Cara, Bicer, Bulent, Govindasamy, Tamizhmani
• Format: Conference Proceeding
• Language: English
• Published: IEEE 09-06-2024
• Subjects: Leaching; Lead; Silicon; Solar panels; Tellurium; Testing; Toxicology; Wire
• ISSN: 2995-1755
• DOI: 10.1109/PVSC57443.2024.10748888

The purpose of this paper is to present and statistically analyze a TCLP (Toxicity Characteristics Leaching Procedure) database that was created from 94 TCLP test results obtained on 33 crystalline silicon and cadmium telluride modules (1-5 samples and tests per module) from 16 different manufacturers. The samples (9.5 × 9.5 mm pieces) required for the TCLP testing were cut from each module using a waterjet cutting approach explained in the ASTM E3325:2021 standard. The TCLP results show that there is a 9% failure rate in meeting the TCLP standard, EPA 1311. The database has been statistically analyzed and presented for a correlation between leaching extent of lead (Pb) in the TCLP tests of all the samples and several variables including module age, glass/glass or glass/backsheet construction, cell technology (BSF, PERC, IBC etc.) and interconnection technology (ribbon or wire). A comparative analysis between three pairs of field-aged and fresh modules with identical models and structures revealed that the field-aged modules tend to experience higher layer separation leading to higher leaching potential compared to fresh modules. The statistically predicted Pb leaching extent in: the advanced crystalline silicon cell technologies is lower than the traditional cell technologies; the wire technologies is lower than the ribbon technologies; and, the glass/glass construction is lower than the glass/backsheet construction.