Evaluation and Comparisons of the Models to Calculate Solar Irradiation on Inclined Solar Panels for Ankara

Özden, Talat
Akınoğlu, Bülent Gültekin
Karaveli, Abdullah Buğrahan
In the optimization and feasibility analysis of renewable energy systems, the accuracy of the simulation methods is extremely important. Thus, in the case of solar energy systems, estimating the monthly average daily solar irradiation incident on inclined solar panels is the main step of long-term feasibility analysis toward reaching the viable investments. In fact, most solar energy investor companies use silicon solar irradiation measuring instruments in Turkey although only a few of them also measure the solar irradiation using accurate instrumentation. Nevertheless, the need to estimate is still very essential and will continue to be so, mainly because of the fact that such on-land measurements are localized at single points on the Earth. In fact, the input, must be estimated or measured accurately to reach the efficiencies (output/input) of the systems. Consequently, this study analysis and compares the models to predict the solar irradiation on inclined surface in the most accurate way for Ankara. To this aim, the measurements have been taken since April 2016. Hourly isotropic model, two anisotropic models HDKR and Perez are used to estimate hourly solar irradiation on inclined surface and converted into monthly mean daily values. Meanwhile, isotropic sky model based on monthly average daily values is also used in the calculations, by utilizing a recent methodology developed by the authors to predict the diffuse component of solar irradiation falling on a horizontal surface. The analysis is carried out using the measurements of two Kipp and Zonen (CMP11) thermopile pyranometers and a new generation silicon pyranometer. The results show that HDKR is the best method. Another important result shows that the measurements of new generation silicon pyranometer has still considerable errors.
Citation Formats
T. Özden, B. G. Akınoğlu, and A. B. Karaveli, “Evaluation and Comparisons of the Models to Calculate Solar Irradiation on Inclined Solar Panels for Ankara,” RAI Convention & Exhibition Centre AMSTERDAM, Netherland, 2017, p. 2501 , Accessed: 00, 2021. [Online]. Available: http://www.eupvsec-proceedings.com/proceedings/dvd.html.