Moreno Tejera, SaraLarrañeta, MiguelLillo Bravo, IsidoroSilva Pérez, Manuel Antonio2021-03-232021-03-232020-12Moreno Tejera, S., Larrañeta, M., Lillo Bravo, I. y Silva Pérez, M.A. (2020). A normalized variability index of daily solar radiation. En International Conference on Concentrating Solar Power and Chemical Energy Systems, SolarPACES 2019 Daegu, South Korea: American Institute of Physics Inc..97807354403710094-243Xhttps://hdl.handle.net/11441/106471AIP Conference Proceeding 2303, 180005-1–180005-8The Variability Index (VI) is widely used to quantify the intra-day solar radiation variability. It compares the length of the global horizontal irradiance (GHI) or direct normal irradiance (DNI) profiles with the length of the corresponding clear sky GHI/DNI profiles. The VI is not a normalized index, it shows dependency on the day of the year, geographic location and time resolution. Thus, the quantification of the intra-day variability of the solar resource between different locations or different seasons could be mistaken. In this work, we propose a novel definition of the VI in order to normalize it (VI’). Moreover, we suggest a methodology to assess the dependencies of the intra-day solar resource variability quantifiers with the day of the year, geographic location and time resolution. We evaluate and compare the performance of both indexes in two different locations along two synthetic years and a measured annual dataset in different time resolutions.application/pdf9 p.engAttribution-NonCommercial-NoDerivatives 4.0 Internacionalhttp://creativecommons.org/licenses/by-nc-nd/4.0/Radiation variabilitySolar RadiationVariability Index (VI)Global horizontal irradiance (GHI)Direct normal irradiance (DNI)info:eu-repo/semantics/conferenceObjectinfo:eu-repo/semantics/embargoedAccesshttps://doi.org/10.1063/5.0028919