Emissão de gases de efeito estufa (GEE) e impactos atmosféricos advindos da produção hidroelétrica: estudo de caso da UHe Volta Grande

• Ano de defesa: 2014
• Autor(a) principal: Guilherme de Souza Dias Andrade
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Minas Gerais; UFMG
• Palavras-chave em Português: Meio Ambiente e Recursos Hídricos; Saneamento; Engenharia sanitária
• Link de acesso: http://hdl.handle.net/1843/BUOS-9N5HUL

The number of hydroelectric power plants has been growing, especially in countries with high hydroelectric potential, aiming to attend the global energy demand. Recently, it has been discussed the real contribution of hydropower source for the increasing atmospheric concentration of GHG, especially regarding CO2 and CH4. Although estimations indicate that tropical reservoirs present the highest fluxes, various uncertainties are still to be solved in order for a better understanding and perception about this assumption. Although being a tropical reservoir, Volta Grande reservoir presented diffusive fluxes of CO2 and CH4 remarkably lower than what is established for tropical reservoir. The median flux for CO2 was 19.09 mmol.m-2.d-1, and for CH4 was 224.36 mol.m-2.d-1. Volta Grande reservoir presented CO2 fluxes similar to those seen in tropical, subtropical and temperate regions. However, analyzing within the same region, it was observed that Volta Grande has lower fluxes than Amazonian systems. For CH4 emissions, it was found that Volta Grande has a lower rate than overall tropical reservoirs. The low median flux observed in Volta Grande is a result of many factors working simultaneously, such as low organic matter content, low residence time, and the age of the reservoir. About the atmospheric impact, it was seen that Volta Grande, although located in the tropical region, has an emission-energy produced ratio lower than what is seen in tropical reservoirs, due to the high ratios observed in Amazonian reservoirs. Moreover, it was seen that Volta Grande emits less carbon to the atmosphere per energy produced than its thermoelectric counterpart. Based on these results, it is to note that generalizing tropical reservoirs as great emitters can be misleading, once GHG emissions from hydropower reservoirs vary significantly even among reservoirs located within the same climatic and geographic region.