Estudo da viabilidade econômica de geração de energia em pequena escala no setor agrocafeeiro

Abstract

In view of the global energy panorama, there is a constant search to mitigate the damages caused by the power generation that has been growing wildly since the revolution industrial. Biomass is a source of energy considered clean, mainly due to the fact that that plants during their lifetime consume CO2 and produce O2. Coffee straw is a residue generated in the last stage of processing, when the dry husk is removed from the grain, already in the vicinity of processing facilities where there is considerable consumption of electricity. Brazil produces an average of 2,615,429 tep of coffee straw per year, in the Caparaó region 657,402 tep of coffee straw are produced with a plantation approximately 1,447,101.5 thousand coffee trees. The present work studies a unit producer and processor of coffee in the same region that produces 5000 sacks of coffee weighing 60 kg and generates around 79,746.8 kg of straw per year, and in a partial pruning system that generates 3.5 kg of firewood per coffee tree can generate up to 511.6 tons of firewood per year. one of the difficulties of the use of residues from grain production for thermoelectric generation is the unavailability of equipment aimed at distributed microgeneration, since grains are produced from linear form and the transport of all this biomass would make the investment of large thermoelectric power plants for this fuel. However, the increase in energy prices associated with brazilian government incentives through PRONAF Bioeconomy and the electricity compensation, this scenario has been transformed. In response to the scenario described, this work makes use of a Tesla Pelton turbine adapted and tested in the laboratory by Batista (2009) who operates in a simple Rankine cycle and which in this study would provide of heat from the combustion of coffee straw in the harvest period (5 months) and coffee firewood in the off-season period. Finally, an economic feasibility study is carried out through equipment financing through the PRONAF Bioeconomy incentive program of the federal government that results in a positive result of a payback of 4 years and 4 months.