Statistical Analysis of Solar Position Calculation Algorithms: SPA and Grena 1-5



Photovoltaic System, Solar tracker, solar position calculation algorithms, spa, grena


Photovoltaic systems have been explored as a solution to meet the growing demand for electricity from a clean and renewable source. To improve the performance of photovoltaic systems, a widely used alternative is the implementation of solar trackers. The strategy of sun-tracking most used in photovoltaic power plants with solar trackers applies algorithms to calculate the sun position. This work presents a statistical analysis of six solar position calculation algorithms: Solar Position Algorithm (SPA) and Grena 1-5. The algorithm with the lowest solar vector error was the SPA.


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Author Biographies

Karen Melo, University of Campinas, UNICAMP

Karen Barbosa de Melo . ´e Mestre em Engenharia El´etrica pela Universidade Estadual de Campinas (UNICAMP) e graduada em Engenharia El´etrica pela Universidade Federal do Amazonas (UFAM). Atualmente ´e aluna de doutorado em Engenharia El´etrica na UNICAMP, onde desenvolve pesquisa sobre seguidores solares, algoritmos de c´alculo da posic¸ ˜ao solar e modelagem de irradiˆancia no Laborat´orio de Energia e Sistemas Fotovoltaicos (LESF).

Lucas Ramos Tavares, University of Campinas, UNICAMP

Lucas Ramos Tavares . est´a cursando Estat´ıstica na UNICAMP. Desenvolveu pesquisa sobre banco de dados e an´alise estat´ıstica aplicados a energia solar. Atualmente, tamb´em ´e cientista de dados em uma empresa de TI e consultor de empresas e pesquisadores.

Marcelo Gradella Villalva, University of Campinas (UNICAMP)

Marcelo Gradella Villalva . ´e professor da Faculdade de Engenharia El´etrica e Computac¸ ˜ao (FEEC) da UNICAMP. Doutor e Mestre em Engenharia El´etrica pela UNICAMP. Diretor do Laborat´orio de Energia e Sistemas Fotovoltaicos (LESF) da UNICAMP.


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How to Cite

Melo, K., Tavares, L. R., & Villalva, M. G. (2021). Statistical Analysis of Solar Position Calculation Algorithms: SPA and Grena 1-5. IEEE Latin America Transactions, 19(7), 1145–1152. Retrieved from