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This approach used a look-up table to determine the model parameters and estimate CSNI for half-opening angles between 0.5\u00b0 and 5\u00b0. To develop and validate the proposed model, data from five locations worldwide were used. It was found that the proposed model performs better at the locations under study than the models available in the literature, with relative mean bias error ranging from \u221213.94% to 0.70%. The impact of CSNI for these different half-opening angles on concentrating solar power (CSP) systems was also studied. It was found that neglecting CSNI could lead to up to a 7% difference between the direct normal irradiance (DNI) measured by a field pyrheliometer and the DNI that is captured by CSP systems. Additionally, a case study for parabolic trough concentrators was performed as a way to estimate the impact of higher circumsolar ratios (CSR) on the decrease of the intercept factor for these systems. It was also concluded that if parabolic trough designers aim to reduce the impact of CSNI variation on the intercept factor, then parabolic troughs with higher rim angles are preferred.<\/jats:p>","DOI":"10.3390\/en16247950","type":"journal-article","created":{"date-parts":[[2023,12,7]],"date-time":"2023-12-07T05:57:08Z","timestamp":1701928628000},"page":"7950","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Prediction of Circumsolar Irradiance and Its Impact on CSP Systems under Clear Skies"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-7195-1677","authenticated-orcid":false,"given":"Edgar F.M.","family":"Abreu","sequence":"first","affiliation":[{"name":"Instituto de Ci\u00eancias da Terra, Universidade de \u00c9vora, Rua Rom\u00e3o Ramalho 59, 7000-671 \u00c9vora, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6210-1964","authenticated-orcid":false,"given":"Paulo","family":"Canhoto","sequence":"additional","affiliation":[{"name":"Instituto de Ci\u00eancias da Terra, Universidade de \u00c9vora, Rua Rom\u00e3o Ramalho 59, 7000-671 \u00c9vora, Portugal"},{"name":"Departamento de Engenharia Mecatr\u00f3nica, Escola de Ci\u00eancias e Tecnologia, Universidade de \u00c9vora, Rua Rom\u00e3o Ramalho 59, 7000-671 \u00c9vora, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2981-2232","authenticated-orcid":false,"given":"Maria Jo\u00e3o","family":"Costa","sequence":"additional","affiliation":[{"name":"Instituto de Ci\u00eancias da Terra, Universidade de \u00c9vora, Rua Rom\u00e3o Ramalho 59, 7000-671 \u00c9vora, Portugal"},{"name":"Departamento de F\u00edsica, Escola de Ci\u00eancias e Tecnologia, Universidade de \u00c9vora, Rua Rom\u00e3o Ramalho 59, 7000-671 \u00c9vora, Portugal"},{"name":"Earth Remote Sensing Laboratory\u2014EaRSLab, Universidade de \u00c9vora, Rua Rom\u00e3o Ramalho 59, 7000-671 \u00c9vora, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2023,12,7]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1121","DOI":"10.1016\/j.solener.2017.07.059","article-title":"Analysis on the Long-Term Relationship between DNI and CSP Yield Production for Different Technologies","volume":"155","author":"Polo","year":"2017","journal-title":"Sol. 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