Abstract
The environmental concerns together with the decrease in technology cost lead the solar market to growth rapidly along the last decade. The photovoltaic (PV) systems are one of the solar energy alternatives and the silicon solar cells are currently the most widespread technology. Photovoltaic (PV) modules are considered the most reliable component of a photovoltaic system. The reliability and lifetime depends on the modules energy conversion performance and degradation modes. The analysis of monitoring data give insights about the PV system performance along its service time. The comparison between this data and mathematical models configure a way to predict the futures and new PV installations performance. The goal of this study is to understand the PV systems performance and degradation along its lifetime. A mathematical model was employed to predict the power output of a real, relatively new operating PV system with respect to environmental parameters temperature, irradiance and cloud coverage. The model used is based on one diode ideality factor and takes into account the parasitic series resistance. The results have been compared with the actual PV output data collected for the year 2014 and show good correlation. As the model predicts the system power output assuming the system in new conditions, the deviation in performance of the real data in comparison to the modeling results need to be further investigated for systems in service for longer time. For this propose, the study presents a condensed review of various causes of degradation in silicon PV modules and techniques to observe and investigate these degradation mechanisms. Major effects on output performance exhibit increase in observed ideality factor n2 and recombination current J02 primarily caused by decrease in minority carrier lifetime, shunts and increase in series resistance. The study further, investigates the governing degradation modes on a ten years old PV crystalline silicon module operating under the similar weather conditions and the resultant effect on its performance. IR imaging for hot spot detection has been employed in examining on this PV module that shows localized damaged regions. PV I-V characteristics reveal some cells performing poorly in the panel due to these degradations. This work may lead to future work on developing models that include dynamic changes in cell/module parameters and techniques to mitigate / inspect / monitor degradation in real time.
Library of Congress Subject Headings
Photovoltaic power systems--Testing; Photovoltaic power systems--Mathematical models
Publication Date
6-2016
Document Type
Thesis
Student Type
Graduate
Degree Name
Materials Science and Engineering (MS)
Department, Program, or Center
School of Chemistry and Materials Science (COS)
Advisor
Santosh K. Kurinec
Advisor/Committee Member
Gabrielle Gaustad
Advisor/Committee Member
Clark G. Hochgraf
Recommended Citation
Da Silva Freire, Felipe, "Performance and Degradation Analysis of Operating PV Systems" (2016). Thesis. Rochester Institute of Technology. Accessed from
https://repository.rit.edu/theses/9259
DaSilvaFreireSupplement2.m (5 kB)
DaSilvaFreireSupplement3.m (5 kB)
Campus
RIT – Main Campus
Comments
Physical copy available from RIT's Wallace Library at TK1087 .D3 2016