Resumo:
The present investigation aims to determine the technical and economic potentials of electricity
generation from different types of biomasses in the state of Minas Gerais, using different electricity
generation technologies, supported by different thermochemical combustion and gasification
routes. The five most available biomasses in the state of Minas Gerais were selected: corn,
soybeans, coffee, eucalyptus and sugar cane, whose crops produce residues that can be used for
electricity generation. Considering the technical, logistical and economic data of the selected
biomasses, the research sought to define the most viable types of residual biomass for electricity
generation, in different locations within the state, through a multi-criteria decision-making
approach (MCDM). A bibliographic review of the maturity of different types of electricity
generation technologies from biomass was carried out, based on available information, schemes
and operational parameters of real installations. The level of technological readiness of the
different alternatives was also evaluated through a survey with specialists in the sector, concluding
that the technologies with the highest level of readiness are the conventional Rankine cycle, the
organic Rankine cycle and the use of gasifiers integrated with internal combustion. These three
technological alternatives were adopted as options for the generation of electricity from biomass,
obtaining a scale of the types of biomasses available, through a multicriteria methodology. The
determination of the criteria weight was carried out from an integration with the analytical
hierarchy process (AHP). In conjunction with a GIS-MCDA approach, different micro-regions
were evaluated considering their respective biomass resources, allowing the estimation of costs
and performance of different electricity production technologies. A logical algorithm was
developed for the selection of alternatives for energy production from biomass, giving priority to
technical feasibility, and considering factors such as the availability of biomass and its
characteristics such as calorific value, humidity and granulometry. Investment costs, operating
costs, as well as logistical costs for generating electricity from the plant, according to the
technology used, were surveyed. Typical energy efficiencies for these cycles are between 8 and
30%, with conversion efficiency increasing with generation scale. To be analyzed, the generation
systems were divided according to their power ranges in industrial application through power
curves, in which plants with power above 5 MWe were to use the conventional Rankine cycle,
power between 0.5 and 4.1 MWe using organic Rankine cycles, and the lower capacity potentials
adopting the gasification and syngas burning cycles in internal combustion engines. It was found
that eucalyptus prevailed as the most suitable biomass for most of the cases analyzed, due to its
high energy power, followed by sugarcane residues, which are produced in greater quantities in
the state. The conventional Rankine cycle was identified as the most mature technology and also
had the lowest generation costs. In the projects that showed economic viability, the generation
costs were between US$ 0.10/kWh and US$ 0.24/kWh.