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Title: PV Degradation Curves: Non-Linearities and Failure Modes

Abstract

Photovoltaic (PV) reliability and durability have seen increased interest in recent years. Historically, and as a preliminarily reasonable approximation, linear degradation rates have been used to quantify long-term module and system performance. The underlying assumption of linearity can be violated at the beginning of the life, as has been well documented, especially for thin-film technology. Additionally, non-linearities in the wear-out phase can have significant economic impact and appear to be linked to different failure modes. In addition, associating specific degradation and failure modes with specific time series behavior will aid in duplicating these degradation modes in accelerated tests and, eventually, in service life prediction. In this paper, we discuss different degradation modes and how some of these may cause approximately linear degradation within the measurement uncertainty (e.g., modules that were mainly affected by encapsulant discoloration) while other degradation modes lead to distinctly non-linear degradation (e.g., hot spots caused by cracked cells or solder bond failures and corrosion). The various behaviors are summarized with the goal of aiding in predictions of what may be seen in other systems.

Authors:
; ; ;
Publication Date:
Research Org.:
National Renewable Energy Lab. (NREL), Golden, CO (United States)
Sponsoring Org.:
USDOE Office of Energy Efficiency and Renewable Energy (EERE), Solar Energy Technologies Office (EE-4S)
OSTI Identifier:
1369127
Report Number(s):
NREL/JA-5J00-65860
Journal ID: ISSN 1099-159X
DOE Contract Number:
AC36-08GO28308
Resource Type:
Journal Article
Resource Relation:
Journal Name: Progress in Photovoltaics. Research and Applications; Journal Volume: 25; Journal Issue: 7
Country of Publication:
United States
Language:
English
Subject:
14 SOLAR ENERGY; 47 OTHER INSTRUMENTATION; PV degradation; durability; reliability; failure mode; non-linearity

Citation Formats

Jordan, Dirk C., Silverman, Timothy J., Sekulic, Bill, and Kurtz, Sarah R.. PV Degradation Curves: Non-Linearities and Failure Modes. United States: N. p., 2016. Web. doi:10.1002/pip.2835.
Jordan, Dirk C., Silverman, Timothy J., Sekulic, Bill, & Kurtz, Sarah R.. PV Degradation Curves: Non-Linearities and Failure Modes. United States. doi:10.1002/pip.2835.
Jordan, Dirk C., Silverman, Timothy J., Sekulic, Bill, and Kurtz, Sarah R.. 2016. "PV Degradation Curves: Non-Linearities and Failure Modes". United States. doi:10.1002/pip.2835.
@article{osti_1369127,
title = {PV Degradation Curves: Non-Linearities and Failure Modes},
author = {Jordan, Dirk C. and Silverman, Timothy J. and Sekulic, Bill and Kurtz, Sarah R.},
abstractNote = {Photovoltaic (PV) reliability and durability have seen increased interest in recent years. Historically, and as a preliminarily reasonable approximation, linear degradation rates have been used to quantify long-term module and system performance. The underlying assumption of linearity can be violated at the beginning of the life, as has been well documented, especially for thin-film technology. Additionally, non-linearities in the wear-out phase can have significant economic impact and appear to be linked to different failure modes. In addition, associating specific degradation and failure modes with specific time series behavior will aid in duplicating these degradation modes in accelerated tests and, eventually, in service life prediction. In this paper, we discuss different degradation modes and how some of these may cause approximately linear degradation within the measurement uncertainty (e.g., modules that were mainly affected by encapsulant discoloration) while other degradation modes lead to distinctly non-linear degradation (e.g., hot spots caused by cracked cells or solder bond failures and corrosion). The various behaviors are summarized with the goal of aiding in predictions of what may be seen in other systems.},
doi = {10.1002/pip.2835},
journal = {Progress in Photovoltaics. Research and Applications},
number = 7,
volume = 25,
place = {United States},
year = 2016,
month = 9
}
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