Search documents

Browse topics

Document details

Key Performance Indicators and PV Module Reliability
G. Kleiss
Reliability, Solar Module, Solar Inverters, Failure Rate, Weibull Distribution, Failure Model
Photovoltaic Modules and BoS Components
Subtopic: PV Module Design, Manufacture, Performance and Reliability
Event: 35th European Photovoltaic Solar Energy Conference and Exhibition
Session: 5CV.3.42
1355 - 1359
ISBN: 3-936338-50-7
Paper DOI: 10.4229/35thEUPVSEC20182018-5CV.3.42
0,00 EUR
Document(s): paper, poster


This work investigates typical Key Performance Indicators used in solar industry for assessment of the performance of solar modules and Balance-of-Systems (BOS) components. It is most important from the point-of-view of an investor in PV systems to have a comprehensive insight into the reliability of solar modules and inverters as those form a major capital expenditure of the project. Since reliability and longevity of such components is crucial for the long term financial success of the project, corresponding key performance indicators (KPI) are desired. To this end solar industry has traditionally provided KPI’s for both solar modules as wells as inverters on the base of relating the number of failed (claimed) product to the number of installed (or sold) product. The denominator of this KPIs may be referred to as either related to the same period as the numerator or to a cumulated number of installations. In the frame of this study it is shown, that currently used KPIs are not sufficient when comparing the ability of solar manufacturers to produce reliable solar modules or inverters. Reference is made to a failure model based on a Weibull distribution. Analytical models based on the Weibull distribution function are given.