Infant mortality rate of field deployed photovoltaic (PV) modules may be expected to be higher than that estimated by standard qualification tests. The reason for increased failure rates may be attributed to the high system voltages. High voltages (HV) in grid connected modules induce additional stress factors that cause new degradation mechanisms. These new degradation mechanisms are not recognized by qualification stress tests. To study and model the effect of high system voltages, recently, potential induced degradation (PID) test method has been introduced. Using PID studies, it has been reported that high voltage failure rates are essentially due to increased leakage currents from active semiconducting layer to the grounded module frame, through encapsulant and/or glass. This project involved designing and commissioning of a new PID test bed at Photovoltaic Reliability Laboratory (PRL) of Arizona State University (ASU) to study the mechanisms of HV induced degradation. In this study, PID stress tests have been performed on accelerated stress modules, in addition to fresh modules of crystalline silicon technology. Accelerated stressing includes thermal cycling (TC200 cycles) and damp heat (1000 hours) tests as per IEC 61215. Failure rates in field deployed modules that are exposed to long term weather conditions are better simulated by conducting HV tests on prior accelerated stress tested modules. The PID testing was performed in 3 phases on a set of 5 mono crystalline silicon modules. In Phase-I of PID test, a positive bias of +600 V was applied, between shorted leads and frame of each module, on 3 modules with conducting carbon coating on glass superstrate. The 3 module set was comprised of: 1 fresh control, TC200 and DH1000. The PID test was conducted in an environmental chamber by stressing the modules at 85°C, for 35 hours with an intermittent evaluation for Arrhenius effects. In the Phase-II, a negative bias of -600 V was applied on a set of 3 modules in the chamber as defined above. The 3 module set in phase-II was comprised of: control module from phase-I, TC200 and DH1000. In the Phase-III, the same set of 3 modules which were used in the phase-II again subjected to +600 V bias to observe the recovery of lost power during the Phase-II. Electrical performance, infrared (IR) and electroluminescence (EL) were done prior and post PID testing. It was observed that high voltage positive bias in the first phase resulted in little/no power loss, high voltage negative bias in the second phase caused significant power loss and the high voltage positive bias in the third phase resulted in major recovery of lost power.

The proceedings present a selection of refereed papers presented at the 1st International Conference on Electronic Engineering and Renewable Energy (ICEERE 2018) held during 15-17 April 2018, Saidi, Morocco. The contributions from electrical engineers and experts highlight key issues and developments essential to the multifaceted field of electrical engineering systems and seek to address multidisciplinary challenges in Information and Communication Technologies. The book has a special focus on energy challenges for developing the Euro-Mediterranean regions through new renewable energy technologies in the agricultural and rural areas. The book is intended for academia, including graduate students, experienced researchers and industrial practitioners working in the fields of Electronic Engineering and Renewable Energy.

Degradation, Mitigation and Forecasting Approaches in Thin Film Photovoltaics covers detailed descriptions of cell to module level fundamentals of photovoltaics including thin-film materials, performance, maintenance procedures and performance forecasting approaches. Designed to help readers better understand the complexities of photovoltaics, covering the most important aspects of PV cell design, fabrication and performance limiting issues coupled with case studies dedicated towards the forecasting approaches for performance degradations occurring in PV panels. Through theoretical and experimental techniques and methods for performance prediction of the PV cells and modules, this reference concludes with an analysis of the emerging PV technologies for the future. Particularly helpful to researchers because the chapters are aligned in a way that enables readers to start from the fundamentals of PVs and end up with a sound understanding of the current and upcoming PV challenges and ways to deal with them. - Describes thin-film photovoltaics from material to cell level, along with performance limiting issues - Addresses issues pertaining to photovoltaic panel maintenance and cleaning procedures - Includes forecasting approaches of potential induced degradation occurring in PVs through theoretical and experimental methods

Photovoltaic (PV) modules undergo performance degradation depending on climatic conditions, applications, and system configurations. The performance degradation prediction of PV modules is primarily based on accelerated life testing (ALT) procedures. In order to further strengthen the ALT process, additional investigation of the power degradation of field aged PV modules in various configurations is required. A detailed investigation of 1,900 field aged (12-18 years) PV modules deployed in a power plant application was conducted for this study. Analysis was based on the current-voltage (I-V) measurement of all the 1,900 modules individually. I-V curve data of individual modules formed the basis for calculating the performance degradation of the modules. The percentage performance degradation and rates of degradation were compared to an earlier study done at the same plant. The current research was primarily focused on identifying the extent of potential induced degradation (PID) of individual modules with reference to the negative ground potential. To investigate this, the arrangement and connection of the individual modules/strings was examined in detail. The study also examined the extent of underperformance of every series string due to performance mismatch of individual modules in that string. The power loss due to individual module degradation and module mismatch at string level was then compared to the rated value.

Provides practical guidance on the latest quality assurance and accelerated stress test methods for improved long-term performance prediction of PV modules This book has been written from a historical perspective to guide readers through how the PV industry learned what the failure and degradation modes of PV modules were, how accelerated tests were developed to cause the same failures and degradations in the laboratory, and then how these tests were used as tools to guide the design and fabrication of reliable and long-life modules. Photovoltaic Module Reliability starts with a brief history of photovoltaics, discussing some of the different types of materials and devices used for commercial solar cells. It then goes on to offer chapters on: Module Failure Modes; Development of Accelerated Stress Tests; Qualification Testing; and Failure Analysis Tools. Next, it examines the use of quality management systems to manufacture PV modules. Subsequent chapters cover the PVQAT Effort; the Conformity Assessment and IECRE; and Predicting PV Module Service Life. The book finishes with a look at what the future holds for PV. A comprehensive treatment of current photovoltaic (PV) technology reliability and necessary improvement to become a significant part of the electric utility supply system Well documented with experimental and practical cases throughout, enhancing relevance to both scientific community and industry Timely contribution to the harmonization of methodological aspects of PV reliability evaluation with test procedures implemented to certify PV module quality Written by a leading international authority in PV module reliability Photovoltaic Module Reliability is an excellent book for anyone interested in PV module reliability, including those working directly on PV module and system reliability and preparing to purchase modules for deployment.

Bifacial photovoltaic (PV) modules are able to utilize light from both sides and can therefore significantly increase the electric yield of PV power plants, thus reducing the cost and improving profitability. Bifacial PV technology has a huge potential to reach a major market share, in particular when considering utility scale PV plants. Accordingly, bifacial PV is currently attracting increasing attention from involved engineers, scientists and investors.