Arun Kumar

Visual Degradation in Field-Aged Crystalline Silicon PV Modules in India and Correlation With Electrical Degradation

This paper presents the analysis of visual degradation data collected during an All-India Survey of Photovoltaic Module Degradation conducted in 2013, in which 57 crystalline silicon modules were inspected in the five different climatic zones of India. Analysis of the data indicates that the highest percentage of modules suffered discoloration in the Hot and Dry climatic zone, with the Hot and Humid zone coming in second in the list. A higher percentage of modules have suffered corrosion in the Hot and Humid zone, as compared with other zones. The modules installed in the Cold climate suffered the least degradation. Both discoloration and corrosion have been seen in modules across all age groups, even in some of the modules installed less than five years ago. On the other hand, delamination and backsheet degradation have been seen only in modules more than a decade old. The visual degradation data have been correlated with the electrical performance data and reaffirm the direct relation between encapsulant discoloration and reduction in short-circuit current and output power, as well as that of series resistance with metal corrosion.

Performance degradation in field-aged crystalline silicon PV modules in different indian climatic conditions

A survey of field-aged crystalline silicon modules in various climatic conditions in India was carried out, focusing on modules, which show visible signs of degradation. Analysis of the survey data indicates that the power degradation rate is highest in the Hot & Dry climatic zone, followed by the Hot & Humid zone, while it is least in the Cold zone. The degradation in power output of crystalline silicon modules is primarily due to reduction in the short-circuit current, followed by decrease in fill factor while the decrease in open-circuit voltage is very small. Analysis of the survey data also indicates that degradation rate of multi-crystalline silicon is slightly higher than that of mono crystalline silicon.

Linking performance of PV systems in India with socio-economic aspects of installation

A survey of PV modules in the field for more than 5 years in India has been conducted The analysis revealed that module degradation rates are linked with the social and behavioral issues of the end users. The appropriateness in system installation, maintenance and hence the degradation depends on the type of ownership of the system, the financial model for the installation and the end purpose. We found that whenever there are cash flows associated with the installations in terms of savings or income generation, the maintenance activities are properly done, irrespective of the type of ownership of the system. Community owned PV installations were found to be better installed and maintained than individual systems because of the presence of institutionalized mechanisms for operation and maintenance.

A study of SnS recrystallization by post deposition treatment

Tin sulfide is one of the most promising alternative materials for photovoltaic. One main requirement for enhancing device efficiency is high quality SnS thin films. We present our study of recrystallization of SnS thin film by post deposition treatment at high temperature with KI and SnCl2. A recrystallization of SnS was achieved with both KI and SnCl2, but it has been observed that this phenomenon occurs only when SnS film is deposited at high temperature, whereas for low temperature-SnS film the treatment process produces a mix of secondary phases into the SnS matrix.

Analysis of spectrum variations in different seasons in composite climate zone of India

This Paper presents the study about the seasonal variations in SUN spectrum under composite climate zone of India through estimation of Average Photon Energy (APE) as quality indicator of the spectrum. Annually the APE varied form 1.81 eV to 1.98 eV. The values of APE varied between 1.88 eV to 1.9 eV during summer, 1.90 eV to 1.98 eV during monsoon and 1.81 eV to1.86 eV during winter seasons respectively. The APE for the standard AM1.5 spectrum is 1.878 eV.

Large area cathode development for high rate deposition of amorphous and nano crystalline silicon

United Solar Ovonic LLC. has developed a large area cathode for high rate plasma enhanced chemical vapor deposition (PECVD) using high frequency (HF, 10s to 100s MHz) which will enable us to build roll-to-roll (RTR) production systems for silicon based thin film solar cells.