Analysis and Evaluation of Gap Filling Procedures for Solar Radiation Data

摘要

Concentrated Solar Power (CSP) has been gaining significance as renewable energy source, especially because it converts solar energy to electricity with dispatchable features, unlike solar photovoltaic. The solar radiation forecasting for CSP depends primarily on a historical database of the solar potential at the plant site, so the irradiation behavior monitoring through sensors is necessary, as well as to fill in the gaps generated by the occurrence of incorrect measurements. This paper presents a comparison between two methods for gap filling: the algebraic equation of the irradiations composition and linear interpolation. The analyses considered Diffuse Horizontal Irradiance (DHI), Global Horizontal Irradiance (GHI) and Direct Normal Irradiance (DNI) during the first three months of 2018. Average error and confidence interval calculations were performed for each component and results show that both methods presented satisfactory results, with the algebraic formula being better suited to the shape of the curve, while the interpolation is more abrupt and conservative.