Modelo de avaliação técnica e econômica do uso de biodigestores na geração de energia elétrica e biofertilizante com dejetos da bovinocultura

Abstract

The main objective of this work was to propose a model for the evaluation of the technical and economic feasibility of the production of electric energy via biodigesters with cattle manure. In the stageof analysis of technical aspects, a survey was carried out of which aspects are relevant in the implementation of the biodigester system. In the economic evaluation, a ranking of Investment Projects (PIs) was first developed, using the Net Present Value (NPV) criterion. Next, the results of the deterministic Multi-Index Methodology MMIA) were analyzed for PIs with NPVs> 0. Finally, for PIs with high sensitivity, Monte Carlo Simulation (SMC) was applied. The feasibility of the evaluation model was tested ona rural property located in the Southwest region of Paraná, comparing three system options, both with ten variations in power. For this, we used the indicators for technical evaluation that showed which of the systems has the best performance for this region, considering the availability of raw material and the climatic conditions. As a technical result it was obtained that the optimum perceptual combination of manure and forage of corn (Project B), are between 22-65%, with the ratio of C: N 25: 1, for thecombination of manure and grass forage ( Project C) is in the 18-54% range. According to the data collected in the application of the analysis model of the technical and economic aspects, the generation of electric energy in the three evaluated systems presented economic advantages as the proportion of the system increases, due to the economy of scale. The results indicate the economic viability of the investment for all evaluated systems, but the viability depends on the installed power. Thus, the choice of the best system and the minimum power are fundamental to ensure the economic viability of the investment.