Abstract
After five or more years of weathering, the degradation of ethylene-vinyl acetate (EVA) encapsulant in photovoltaic (PV) modules resulted in a yellow to dark brown color. Degraded EVA shows a substantial increase in the gel content and a large to complete loss of the ultraviolet (UV) absorber, Cyasorb UV 531. The EVA discoloration is caused by the formation of polyconjugated (C=C)n double bonds of various lengths. Acetic acid and other volatile organic components are also produced from the photothermal decomposition of the EVA. The solar cell efficiency was reduced by approximately 9% by a light-yellow-brown EVA and approximately 50% by a dark-brown EVA. Weathered PV modules with dark-brown EVA also show a approximately 50% decrease in efficiency.
| Original language | American English |
|---|---|
| Pages | 557-561 |
| Number of pages | 5 |
| State | Published - 1992 |
| Externally published | Yes |
| Event | Twenty-second IEEE Photovoltaic Specialist Conference - 1991 - Las Vegas, Nevada Duration: 7 Oct 1991 → 11 Oct 1991 |
Conference
| Conference | Twenty-second IEEE Photovoltaic Specialist Conference - 1991 |
|---|---|
| City | Las Vegas, Nevada |
| Period | 7/10/91 → 11/10/91 |
NREL Publication Number
- NREL/CP-214-4543