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Performance and Reliability of Photovoltaic Systems

The overall objective of Task 13 is to improve the operation, reliability and, consequently, the electrical and economic output of photovoltaic power systems and subsystems through:

  • providing a common platform whereby quality aspects are elaborated and
  • exchanged amongst the stakeholders
  • disseminating this knowledge to different market actors.

Task 13 will focus on:

  • compiling reliable statistical data for a variety of decision makers for different PV applications and system locations (e.g. different countries, regions, climates)
  • technical issues such as adapting test methods and lifetime assessment of PV modules, comparing the long-term behaviour of systems and components, as well as performance analysis and optimization of PV systems
  • economic and institutional issues such as the comparison of investment costs and energy costs, the analysis of maintenance costs of specific components, as well as the analysis of failures and statistics.


The main outputs of this project are summarized in the following sections.


Review of Failures of Photovoltaic Modules

One key factor of reducing the costs of photovoltaic systems is to increase the reliability and the service life time of the PV modules. Today’s statistics show degradation rates of the rated power for crystalline silicon PV modules of 0.8%/year. To increase the reliability and the service life of PV modules one has to understand the challenges involved. For this reason, the international Task 13 expert team has summarized the literature as well as their knowledge and personal experiences on actual failures of PV modules.

The target audience of this work is PV module designers, PV industry, engineering lines, test equipment developers, testing companies, technological research laboratories, standardisation committees, as well as national and regional planning authorities.

The full review is available here: PDF-Download


Analytical Monitoring of Grid-Connected Photovoltaic Systems Good Practices for Monitoring and Performance Analysis

This report focuses on the analytical assessment of photovoltaic (PV) plant performance on the overall PV system level. In particular, this report provides detailed guidelines and comprehensive descriptions of methods and models used when analyzing grid-connected PV system performance.

The main objectives of this report are:

  • to propose good practices for PV system monitoring today,
  • to determine and understand PV system losses that cannot be assessed by direct measurements in commercial PV systems,
  • to determine and understand the behavior of new PV technologies in long-term system operation,
  • to learn from previous bad experiences and draw out lessons for new installations in the IEA PVPS member countries.

The full report PDF-Download delivers a comprehensive set of practical guidelines for analytical PV system monitoring. Applied systematically, these guidelines will contribute to further increasing the performance of PV power plants.


Characterization of Performance of Thin-film Photovoltaic Technologies

Although thin-film photovoltaic (PV) modules have been in production for decades, the characterization of their performance, both outdoors and under artificial light, remains a topic of active research. This is because the field contains a diverse set of PV technologies, each of which has physical differences from conventional crystalline silicon PV. These differences range from different temperature coefficients to complex short-term or seasonal transients in performance. This report summarizes the nature of these special behaviours and demonstrates best practices for handling them in the context of several case studies.

The full report can be downloaded here: PDF-Download


Analysis of Long-Term Performance of PV Systems

This report investigates data supplied from installed operating PV plants in different countries in order to improve understanding of efficiency and reliability issues of current state-of-the-art PV systems.


This report can be downloaded here: PDF-Download


Assessment of Photovoltaic Module Failures in the Field

In this report we present the current status and predictive ability for the power loss of PV modules for specific failure modes. In order to model PV module degradation modes it is necessary to understand the underlying degradation mechanisms and processes on the molecular level.

The literature review shows that PV module failure modes are well described, including their main driving factors. The review also shows that the right combination of the encapsulant and backsheet films can be beneficial in reducing failures.

Besides PV module failure, the failure with the highest impact on the PV system is the soiling of PV modules in specific outdoor regions. A special stressor classification for PV modules for soiling in the Middle East and North Africa regions is introduced.

This report can be downloaded here: PDF-Download


PV Performance Modeling Methods and Practices

Results from the 4th PV Performance Modeling Collaborative Workshop

The PV Performance Modeling Collaborative (PVPMC) is a group started by Sandia National Laboratories in 2010. It hosts a technical website (pvpmc.sandia.gov), workshops, and open-source modeling function libraries (PVLIB). In 2015, IEA PVPS Task 13 formed a partnership with the PVPMC to increase international participation in this group’s mission.

This report provides a technical overview of the steps to modeling the power and energy output from grid connected PV systems and a summary of the results of the first in a series of joint IEA PVPS Task 13 / PVPMC workshops.

Approximately 220 solar energy experts from over 30 countries and four continents gathered for two days to discuss and share results related to predicting the performance and monitoring the output from solar photovoltaic (PV) systems.

The Technical Report can be downloaded from the IEA-PVPS website www.iea-pvps.org.

This report can be downloaded here: PDF-Download


Technical Assumptions Used in PV Financial Models - Review of Current Practices and Recommendations

PV financial models are used by project developers, banks and asset managers to evaluate the profitability of a PV project. The objective of this work is to present an overview of current practices for financial modelling of PV investments and to review them in view of technical and financial risks during the different phases of a PV project. This report focuses on establishing common practices for translating the technical parameters of performance and reliability into financial terms. The full report delivers a comprehensive set of practical guidelines and recommendations for mitigating and hedging financial risks in a PV investment.

This report can be downloaded here: PDF-Download

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