Fotovoltaik Sistemlerde Verimliliği Etkileyen Faktörlerin İncelenmesi

Abstract

Investments to renewable energy systems increase in recent years due to depletion threat of conventional resources. In this point, one of the developed energy systems technology is photovoltaic systems. By the help of decreasing in solar panel cost and providing high acceptable standards around the World, photovoltaic systems become to be considered as an investment tool. Short term electricity forecasting can be done with margin of error by photovoltaic simulation programs. However, it does not mean that everything is done for obtaining high performance after construction process. Performance anaylsis and investigation of efficiency factors are crucial elements for reaching high efficiency in photovoltaic systems. In operation and maintainance process of most of Solar Power Plants in Turkey are faced with significant problems because of misimplemantaions in constructions processes and this leads to production losses.

In this study, initially, the methods to be used for the calculation of radiation and performance parameters in Theoretical Section are given. After giving general information about Solar Power Plants located in Gölbaşı and Torbalı Districts in the Investigation of Site Data, the performance parameters of the plants and the factors affecting the efficiency are given by the methods given in Theoretical Section; while the radiation parameters are calculated by monthly Global Horiztontal and Diffuse Horizontal Radiation values from the NASA's database. In next section, the PVsyst program was used to model and simulate Solar Power Plants. When examined annually, it is seen that the production values obtained by simulation are close to those obtained from solar inverters. In the evaluation section field results and simulation results are compared and it is concluded that the difference between the system performance ratios calculated from the simulations and field data of two plants is less than 1%. Among the efficiency loss factors in Gölbaşı GES and Torbalı GES facilities, temperature loss was found to be the most effective factor causing the loss. Loss of temperature is followed by soiling loss, IAM loss, and mismatch loss. In addition, in this section, the effect of annual energy production on the decrease of temperature loss and soiling loss, which are the most influential factors of power plants, has been evaluated. In the case of Torbalı GES, the increase in the duration of contact with the wind surface of the solar panel back surface will decrease the temperature loss and increase by 3,5% in annual production. Gölbaşı GES has the result that this increase can be 1,2%. If the dust generated in the solar panels is periodically cleaned and the soiling loss is kept at 1% level, the result is that Gölbaşı GES will increase 5% in annual production and 3% in Torbalı GES.