Procedimento para análise da viabilidade econômica do uso do biogás de aterro sanitário para a geração de energia elétrica : aplicação no aterro sanitário Santa Tecla

Abstract

Energy is a vital fuel both for the economic development and the modern society life style. However, the development, the electric energy production and the society itself cause strong impacts, and damage the environment. Nevertheless, the concerning, about the environment has brought issues related to the global warming, acid rain and solid wastes deposit. This study aims to create a procedure to analyze the economic viability of the eletric energy production based on the use of the biogas, which is a result of the anaerobic decomposition of wastes in sanitary landfills. Besides, it also aims to use this procedure at Santa Tecla Metropolitan Sanitary Landfill. The review of literature approaches topics related to the energy usage and the environmental problems such as the ozone layer and the global warming, the solid wastes deposit, biogas, electric energy production in Brazil, economic viability and environmental benefits. In the results, part of this study points out for the development of the proposed procedure composed by the evaluation of biogas production capacity using a first-order decaiment model, electric energy production capacity, cash-flow creation and certified sales of carbon credits. After these steps, the procedure was applied at Santa tecla Metropolitan Landfill. At this landfill there was an internal rate of return (IRR) tax and net present value (NPV) to a 2MW power plant. Eight sceneries have been created, each of them considering different values (optimist, conservative, pessimist) for energy and carbon credits sales, to simulate probable future situations. Thus, the electric energy power plant installation would bring, as financial benefits, the moneymaking possibility through biogas salesfor the owner of the landfill. In this specific case, city halls would be the first to benefit from it. It would also benefit the entire community, since the biogas produced would reduce public cleaning costs, as well as public illumination taxes, which would be provided by the electric energy produced. Other benefits would be the contribution for commercial balance superavit through sales of carbon credits and energetic matrix diversification for the electric system