Annual evolution of global, direct and diffuse radiation and fractions in tilted surfaces

Abstract

The levels of global and direct radiation on tilted surfaces were lower in summer and higher in the equinoxes when compared with the horizontal. The diffuse radiation on tilted surfaces was lower in most months, with losses of up to 65%. A trend of increasing differences occurred between horizontal and tilted surfaces with the increase of the angle in all the components and fractions of incident radiation. The annual evolution of rainfall and cloud cover ratio directly affected the atmospheric transmissivity of direct and diffuse components in the region.KEYWORDS: solar energy, clearness index, atmospheric transmissivity, climatic conditions. EVOLUÇÃO ANUAL DAS RADIAÇÕES E FRAÇÕES GLOBAL, DIRETA E DIFUSA EM SUPERFÍCIES INCLINADASRESUMO: Avaliou-se a evolução anual das componentes global, direta e difusa da radiação solar incidente em superfícies inclinadas a 12,85; 22,85 e 32,85º, com face voltada ao Norte, em Botucatu-SP. Foram obtidas frações radiométricas para cada componente da radiação nas superfícies supracitadas, através de razões com a radiação global e a do topo da atmosfera. A sazonalidade foi avaliada através das médias mensais dos valores diários. As medidas ocorreram entre 04

Radiação global e difusa diária na região de transição Cerrado-Amazônia brasileira

“…However, since the radiation is transmitted, there is an inversion process of the diffuse radiation between the cloud and the surface, wherein scattering with isotropic characteristics is generated. In turn, in the dry season isotropic and anisotropic scattering occur together (CHWIEDUK, 2009;POSADILLO;LUQUE, 2009;SOUZA et al, 2012;ESCOBEDO, 2013;DAL PAI et al, 2016).…”

“…Knowledge of solar radiation levels at the terrestrial surface is essential for energy use projects and research in a wide variety of fields, including agriculture (e.g., water use by plants and models of development or crop production); various aspects of atmospheric chemistry (e.g., the ozone layer and air quality), meteorology and climatology (e.g., hydric and energetic balance and climate-ocean interactions); energy efficiency and thermal comfort practices in architecture and construction (e.g., use of solar thermal energy as a potential alternative for water heating); and even solutions for water desalination (PEREIRA et al, 2006;SOUZA et al, 2012;CRUZ et al, 2020;SHARQAWY, 2020).…”

Eficiência Energética, Pesquisa E Desenvolvimento E Geração Fotovoltaica Na Ufac (Universidade Federal Do Acre)

“…A espessura da camada atmosférica a ser atravessada pelos raios solares depende proporcionalmente de θ Z . Do contrário, quando há um aumento da extensão do céu encoberto com nuvens, ocorre um acréscimo em intensidade da componente de radiação difusa e um decréscimo da componente de radiação direta (Souza et al, 2012 (GT Brasília Solar, 2016).…”