In the last decade, there has been a dramatic increase in the numbers of photovoltaic (PV) Systems as the world shifts toward clean and sustainable energy resources. Seeing this rise in the Solar PV market, multiple new manufacturers are seeking entry into the marketplace and the need to identify the good performance modules from the bad becomes an absolute necessity. The Performance and reliable operation of PV Modules depend on many factors including materials, manufacturing processes and environmental constraints. Even best quality PV modules and systems degrade with time. The degradation rate largely depends on field conditions and manufacturers, as well as test engineers are highly interested in accurate performance modeling of the field installed PV modules. Thus two factors have been seen to give good indications of the degradation: the Performance Ratio and the Performance Index. As a power plant in Pakistan is analyzed for its degradation using these two factors in this paper, an indication on its possible lifetime can be predicted. The performance ratio method indicated at degradation of 0.61% while the performance index method indicated a degradation of 1.09%.
Shakeel Ahmed Muhammad Younas and Fahim-ur-Rehman Statistical Determination of Climate-Specific defects and Degradation Modes in PV Modules International Journal of Engineering Works Vol. 6 Issue 03 PP. 98-105 March 2019
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