Degradations of silicon photovoltaic modules: A literature review

http://oa.upm.es/10081/2/doi.10.1016.j.solener.2011.06.011.pdf

Early degradation of silicon PV modules and guaranty conditions

Faults in any components (modules, connection lines, converters, inverters, etc.) of photovoltaic (PV) systems (stand-alone, grid-connected or hybrid PV systems) can seriously affect the efficiency, energy yield as well as the security and reliability of the entire PV plant, if not detected and corrected quickly. In addition, if some faults persist (e.g. arc fault, ground fault and line-to-line fault) they can lead to risk of fire. Fault detection and diagnosis (FDD) methods are indispensable for the system reliability, operation at high efficiency, and safety of the PV plant. In this paper, the types and causes of PV systems (PVS) failures are presented, then different methods proposed in literature for FDD of PVS are reviewed and discussed; particularly faults occurring in PV arrays (PVA). Special attention is paid to methods that can accurately detect, localise and classify possible faults occurring in a PVA. The advantages and limits of FDD methods in terms of feasibility, complexity, cost-effectiveness and generalisation capability for large-scale integration are highlighted. Based on the reviewed papers, challenges and recommendations for future research direction are also provided.

Fault detection and diagnosis methods for photovoltaic systems: A review

Potential-induced degradation (PID) has received considerable attention in recent years due to its detrimental impact on photovoltaic (PV) module performance under field conditions. Both crystalline silicon (c-Si) and thin-film PV modules are susceptible to PID. While extensive studies have already been conducted in this area, the understanding of the PID phenomena is still incomplete and it remains a major problem in the PV industry. Herein, a critical review of the available literature is given to serve as a one-stop source for understanding the current status of PID research. This paper also aims to provide an overview of future research paths to address PID-related issues. This paper consists of three parts. In the first part, the modelling of leakage current paths in the module package is discussed. The PID mechanisms in both c-Si and thin-film PV modules are also comprehensively reviewed. The second part summarizes various test methods to evaluate PV modules for PID. The last part focuses on studies related to PID in the omnipresent p-type c-Si PV modules. The dependence of temperature, humidity and voltage on the progression of PID is examined. Preventive measures against PID at the cell, module and system levels are illustrated. Moreover, PID recovery in standard p-type c-Si PV modules is also studied. Most of the findings from p-type c-Si PV modules are also applicable to other PV module technologies.

https://pubs.rsc.org/en/content/articlepdf/2017/ee/c6ee02271e

Potential-induced degradation in photovoltaic modules: a critical review

Photovoltaic (PV) modules are subject to climate-induced degradation that can affect their efficiency, stability, and operating lifetime. Among the weather and environment related mechanisms, the degradation mechanisms of the prominent polymer encapsulant, ethylene-vinyl-acetate copolymer (EVA), and the relationships of the stability of this material to the overall reliability of Si-based PV modules were addressed. The EVA function and properties correlated to its deterioration factors as temperature, moisture, and ultraviolet radiation (UV) were discussed in this work. The main objective of this study is to review the literature on EVA encapsulation and its degradation, which promotes the loss in performance of the PV module. The deleterious effects on EVA such as photodegradation, moisture, delamination, bubble formation and potential induced degradation (PID), their relationship with the polymer structure, chemical, mechanical, optical and electrical properties are approaches carried out in this review. This paper also provides a brief review of the developing field of EVA composites technology aiming at higher performance materials.

The causes and effects of degradation of encapsulant ethylene vinyl acetate copolymer (EVA) in crystalline silicon photovoltaic modules: A review

Measurements that suppliers offer in specification sheets are not always close to the actual power measured in independent laboratories such as CIEMAT. Independent measurements tend to be lower than those printed on the label sometimes even lower than the allowed tolerance indicated by the manufacturer on the same label. Furthermore, a potentially significant power reduction has been reported when Standard EN50380 (which requires photovoltaic (PV) modules to be exposed to more than 20 kWh/m2 of sunlight prior to taking the measurements that appear on the label) is followed. This is the initial power stabilization and this work studies the power stabilization that tends to appear in crystalline PV modules. Crystalline PV modules usually decrease in power around 1%, but decreases >4% have also been reported. These power losses are only detected after the mentioned power stabilization. Copyright © 2010 John Wiley & Sons, Ltd.

/pdf/influence-of-initial-power-stabilization-over-crystalline-si-17bow5fddu.pdf

M.A. Munoz

Papers

Early degradation of silicon PV modules and guaranty conditions

Influence of initial power stabilization over crystalline-Si photovoltaic modules maximum power