Bringing to light a new energy path. Biomass residues as a contribution to a sustainable and inclusive energy source in Brazil

The use of residual biomass as a source for decentralized and clean energy production that does not affect food security is the most promising option. It comes without the enormous impact of the large-scale hydroelectric dams, can be applied virtually anywhere and does not rely on a connection to the central grid, and does not compete with food supply. The aim of this thesis is to investigate the role that biomass can play in the Brazilian electricity matrix. The hypothesis is that residual biomass as an energy source could play a significant role in transforming the Brazilian energy matrix towards a sustainable path. To attain the overall goal, four general steps were defined: (1) to explore the potential areas for sustainable biomass energy production; (2) to evaluate the perspectives for biomass energy production in peripheral areas; (3) to identify the potential of biomass energy production in one entire state and (4) to evaluate the costs and social acceptance for biomass enterprises. On the First Step, the potentials areas for energy production were identified, in which the use of biomass for a sustainable power production can have a particularly high significance for the energy supply of the population: 1. areas with higher energy demand, 2. areas that were more remote of an installed transmission line, 3. areas far from already installed hydroelectric and thermoelectric power plants, 4. areas with an anthropic land use, and 5. areas of relevance for environment preservation. The main findings of this step were that there is an area of approximately seven million hectares with the potential to produce energy through biomass meeting local demand, favoring areas with fewer power connections, avoiding changes in land use, and maintaining priority areas for environmental conservation. On this basis, a new concept for energy supply could be built. The Second Step had the objective to assess potential areas where the energy could have a positive social impact in an example region. The region chosen for the study is a supplier of eucalyptus charcoal for the iron industries in the west of the state of Minas Gerais. By combining the Human Development Index, the yearly permanent crop production, the yearly silviculture production, and the yearly temporary crop production in a GIS system, it was possible to select three municipalities to study. The results indicate a potential for each of the three investigated small municipalities to be self-sustainable in energy production by using silviculture and agricultural waste, and also that the success of biomass energy generation through agriculture residue enterprises depends on more than energy efficiency. The Third Step focuses on the investigation of the possibilities to sustainably attend the demand on a larger scale. Opportunities for power generation from biomass residues in the whole Minas Gerais State were assessed, considering the silviculture and crop yield and applying a conservative index that considerers the portion of residues that should be used maintaining the soil health. The chosen crops were coffee, corn, beans, manioc, and sugarcane. The assessment of production data is vital to estimate the amount of residue generated in the production process. For all the crops, literature indicates a percentage of rests remaining from harvesting or primary processing. For the estimation of residues from forestry, data were selected on the production of eucalyptus charcoal, firewood, and wood in 2016. To ensure the sustainability of the process, data regarding wood products from native vegetation was not considered in this study. Data were generated per municipality to them be joined at the state level. The primary outcomes were that in a state with the tradition of agriculture, 78% of the municipalities could have their basic energy needs attended. This would relieve pressures placed on the construction of new hydroelectric plants, which have negative impacts on the environment. In addition, a cooperative production system among farmers can reduce costs and may allow the partial improvement of their agricultural raw material. Finally, on the fourth Step, the implementation costs were investigated. In a region were many initiatives have been carried out in order to create new opportunities for people affected by a dam rupture with very negative consequences for land use, it was pursued innovative initiatives for agriculture in the municipalities surrounding the Doce River State Park. There was an interest from the communities to increase the cultivation of certain crops and one possibility proposed to the locals was to use agricultural waste for electricity production. Ensuring the sustainability and development of clean technologies, this step sought to evaluate the potential of energy production through agricultural waste, the ideal allocation of the energy production unit, and the costs involved in the enterprise. The demand of the municipalities was considered as the monthly average consumption per resident (150 kW.h/month) and the market prices of October 2018 were applied for the calculation of the implementation costs, which was conducted by a company that works on the area and applied the potentials and the transportation distances to estimate the costs and the allocation of the power plants accordingly. The calculations of the costs involve collection logistics, transport of materials, purchase, installation, and operation of a power generating unit and team training. From a total of 16, 13 municipalities presented a production capable of meeting about 20% of local demand. Based on the residual potential, transportation costs and current market prices, the most efficient arrangement found would be to build two power plants. This step shows that a significant investment is required. But, the enterprise could be viable and pay itself in a short amount of time.