Photovoltaic module leach testing: Database development and statistical analysis.

Area of Science:

• Materials Science
• Environmental Science
• Renewable Energy

Background:

• Photovoltaic (PV) module disposal and potential environmental impact are growing concerns.
• Understanding heavy metal leaching, particularly lead (Pb), from PV modules is crucial for sustainable end-of-life management.
• Standardized testing procedures are needed to assess the environmental risk associated with PV module components.

Purpose of the Study:

• To compile and analyze Toxicity Characteristic Leaching Procedure (TCLP) test results for a diverse set of 33 photovoltaic (PV) modules.
• To investigate the influence of various module attributes on lead (Pb) leaching characteristics.
• To assess the environmental hazard classification of PV modules based on EPA TCLP limits.

Main Methods:

• Conducted U.S. Environmental Protection Agency (EPA) Toxicity Characteristic Leaching Procedure (TCLP) testing on 97 samples from 33 PV modules.
• Extracted module pieces using waterjet cutting according to ASTM E3325-21 standard practice.
• Analyzed and categorized TCLP results based on module age, cell technology, interconnects, construction, and material type.

Main Results:

• Only 3 out of 33 tested PV modules were classified as hazardous.
• Modules with modern technologies (e.g., PERC, IBC cells, wire interconnects, glass/glass) exhibited lower lead (Pb) leaching probabilities.
• Material aging was identified as a potential factor in increased Pb leaching in two field-aged modules.

Conclusions:

• Modern PV module technologies are associated with a reduced risk of hazardous lead (Pb) leaching.
• The probability of traditional PV technologies leaching lead (Pb) above EPA limits is estimated to be less than 8% under the tested conditions.
• Further expansion of the PV module database is recommended to enhance the representation of deployed technologies and refine risk assessments.