A Review of Solar Energy Use in Biogas Digester Heating. Journal of Solar Energy Research Updates, [S. l.], v. 9, p. 70–81, 2022. DOI: 10.31875/2410-2199.2022.09.07. Disponível em: https://zealpress.com/index.php/jseru/article/view/424. Acesso em: 1 oct. 2025.