TY - JOUR

T1 - Effect of Encapsulant Degradation on Photovoltaic Modules Performances Installed in Different Climates

AU - Barretta, Chiara

AU - Macher, Astrid

AU - Köntges, Marc

AU - Ascencio-Vasquez, Julian

AU - Topic, Marko

AU - Oreski, Gernot

N1 - Publisher Copyright: © 2011-2012 IEEE.

PY - 2025/1/9

Y1 - 2025/1/9

N2 - A damage analysis was conducted on photovoltaic modules with identical bill of materials exposed to different climates: Cfb moderate and Af tropical, according to the Köppen-Geiger climate classification. The combination of high temperature, relative humidity, and high ultraviolet (UV) radiation was the cause of severe degradation for the modules exposed to tropical climates (TR), whereas the module exposed to a moderate climate did not experience a significant loss in performance. The modules installed in TR, on the contrary, showed significant power degradation after approximately 8 years of exposure, primarily attributed to acetic acid-related degradation modes. Encapsulant samples were extracted from the selected modules and characterized to determine changes in chemical structure, thermal stability, and consumption of additives and stabilizers. The results of qualitative additive analysis showed that the UV absorber was no longer detectable in the front encapsulant extracted from modules exposed in TR. The consumption of the stabilizers was considered as the main cause of reduction of molar mass. The presence of acetic acid was evident in both electroluminescence images and ion chromatography results. While differential scanning calorimetry successfully detected a reduction in molar mass, thermogravimetric analysis, and infrared spectroscopy proved unsuitable for identifying chain scission phenomena.

AB - A damage analysis was conducted on photovoltaic modules with identical bill of materials exposed to different climates: Cfb moderate and Af tropical, according to the Köppen-Geiger climate classification. The combination of high temperature, relative humidity, and high ultraviolet (UV) radiation was the cause of severe degradation for the modules exposed to tropical climates (TR), whereas the module exposed to a moderate climate did not experience a significant loss in performance. The modules installed in TR, on the contrary, showed significant power degradation after approximately 8 years of exposure, primarily attributed to acetic acid-related degradation modes. Encapsulant samples were extracted from the selected modules and characterized to determine changes in chemical structure, thermal stability, and consumption of additives and stabilizers. The results of qualitative additive analysis showed that the UV absorber was no longer detectable in the front encapsulant extracted from modules exposed in TR. The consumption of the stabilizers was considered as the main cause of reduction of molar mass. The presence of acetic acid was evident in both electroluminescence images and ion chromatography results. While differential scanning calorimetry successfully detected a reduction in molar mass, thermogravimetric analysis, and infrared spectroscopy proved unsuitable for identifying chain scission phenomena.

KW - Acetic acid

KW - climate

KW - corrosion

KW - crystalline silicon photovoltaic (PV)

KW - degradation

KW - encapsulant

KW - ethylene vinyl acetate (EVA)

KW - power loss

UR - http://www.scopus.com/inward/record.url?scp=85214840682&partnerID=8YFLogxK

U2 - 10.1109/JPHOTOV.2024.3523546

DO - 10.1109/JPHOTOV.2024.3523546

M3 - Article

AN - SCOPUS:85214840682

VL - 15.2025

SP - 290

EP - 296

JO - IEEE Journal of Photovoltaics

JF - IEEE Journal of Photovoltaics

SN - 2156-3381

IS - 2

ER -