Original paper
Classifying ground-measured 1 minute temporal variability within hourly intervals for direct normal irradiances
Schroedter-Homscheidt, Marion; Kosmale, Miriam; Jung, Sandra; Kleissl, Jan
Meteorologische Zeitschrift Vol. 27 No. 2 (2018), p. 161 - 179
46 references
published: Jul 11, 2018
published online: Jan 31, 2018
manuscript accepted: Jan 5, 2018
manuscript revision received: Jan 4, 2018
manuscript revision requested: Nov 29, 2017
manuscript received: Sep 20, 2017
Open Access (paper may be downloaded free of charge)
Abstract
Variability of solar surface irradiances in the 1 minute range is of interest especially for solar energy applications. Eight variability classes are defined for the 1 minute resolved direct normal irradiance (DNI) variability inside an hour. They combine high, medium, and low irradiance conditions with small, medium, and large scale variations from one minute to the next minute.A reference data base of 333 individual hours with ground-based 1 minute DNI observations was created by expert review from one year of observations at the BSRN station in Carpentras, France. Each variability class is represented by 16 to 63 members. Variability indices as previously published or newly suggested are used as classifiers to detect the class members automatically. Up to 77 % of all class members are identified correctly by this automatic scheme. The variability classification method allows the comparison of different project sites in a statistical and automatic manner to quantify short-term variability impacts on solar power production.
Keywords
variability • global horizontal irradiance • direct irradiance • automatic classification • ground-based observations