The ongoing energy transition has resulted in an increased focus on renewable energy systems and their viability for Distributed Generation (DG) applications. In this context, small-scale wind turbines have drawn significant attention due to their compact and adaptable dimensions, making them well-suited for water pumping, irrigation, and energy generation in domestic settings, whether in urban or remote areas. In this way, the main objective of this study was to develop a reliable methodology for optimizing the aerodynamic performance of a small-scale Vertical Axis Wind Turbine (VAWT), specifically the Darrieus H type. To accomplish this, a flexible, accurate, and efficient Computational Fluid Dynamics (CFD) methodology was devised to predict the Power Coefficient (CP) of various configurations of Darrieus H VAWTs. This methodology was calibrated using experimental data from the literature and adapted to minimize the number of simulations related to spatial and temporal discretization independence studies. Furthermore, the CFD methodology was integrated into an optimization procedure based on Response Surfaces (RS), which was constructed using Design of Experiments (DoE) techniques and explored within their domains through Optimization Algorithms (OA) execution. The results of this study provided valuable insights into the configuration of a CFD approach for small-scale Darrieus H VAWTs, with a maximum percentage error of 12% in CP compared to experimental data. Additionally, the optimization procedure resulted in an 11% increase in nominal CP, where the typical CP value for small-scale Darrieus H VAWTs was 0.30, and the maximum percentage error of the CFD methodology was taken into consideration. The maximum value of 0.3778 for solidity (σ) was achieved when σ was equal to 0.24, and the installation angle (β) was equal to -4.1°. In conclusion, the integration of CFD simulation methodologies and RS-based optimization can provide reliable results in a relatively short time, thus serving as a powerful tool in the design of Darrieus H VAWTs.

The growth of renewable energy generation contributes to the decarbonization and diversification of the electricity matrix. However, it also brings challenges to the electricity sector, such as the need to install energy storage systems. In this scenario, reversible hydroelectric power plants (UHR) become relevant, as they have the potential to mitigate the intermittency of renewable sources, such as wind and solar, and increase energy security. In this context, the present work aimed to evaluate the feasibility of implementing UHR to recover the reservoir level in existing hydroelectric power plants (UHE), operating from photovoltaic energy. The existing UHE are used to guarantee energy and system reliability, while the photovoltaic plant is used to stabilize reservoir levels and complement generation. In order to achieve this objective, a simulation of a photovoltaic plant was applied to the potential UHE through the calculation of the complementary power and economic study, selecting the UHE with a low capacity factor with the most subscribers to receive the hybridization project. later, the photovoltaic system was dimensioned for this complementary power, followed by the simulation of the NPV as a function of the power in order to find the optimal complementary power, concluding with the study of the application of the UHR. Aiming at not investing in repowering the substation and line, the results show that the NPV investment curve indicates that it is better to operate with energy loss due to excess generation in a few days than to operate without overcoming the substation and line. Usually with low flow rates and consequently less rainfall, photovoltaic generation achieves higher yields, thus optimizing the UHE's capacity factor and substation/line utilization. The results showed that it is more feasible for the photovoltaic plant to operate with energy loss due to excess generation in a few days than to operate without overcoming the substation power. The viability of the UHR applied for the recovery of the reservoir level is only ensured when high tariffs for the remuneration of the storage system are adopted.

The main objective of this work is to analyze the regulatory aspects of the law of the sea in Brazil, with a focus on the generation of electric energy through the forms of energy coming from the sea, analyzing the structure of the sea, with the discrimination of the maritime spaces, the technologies used for sea exploration will be presented, along with some countries that already explore these types of technology, with the presentation of a brief history of the Brazilian electricity sector and sea exploration, as well as the current Brazilian legislation, so that in the end, the present work is a detailed summary on the legal aspects of the law of the sea for the generation of electric energy.

 Brazil is the only country that produces charcoal on a large scale. However, traditional carbonization processes waste large amounts of energy through the residual carbonization gases that are released into the atmosphere, which cause air pollution and environmental degradation. This fact is a consequence of the technology currently used to produce charcoal, the large rectangular masonry kilns, which make the recovery and use of gases quite difficult. The carbonization gases contain approximately 40% of the energy content of wood, and the large production of charcoal in the Minas Gerais state can represent a considerable energy potential. The objective of this work is to assess the possibility of recovering the energy of the gases produced during wood carbonization in a "Lambiotte" type reactor (retort). Since these reactors operate continuously, they allow better use of wood energy through a gas recovering system that uses part of the gas energy in the charcoal production process itself and part for electricity generation. The carbonization reactor considered can produce 20 tons of charcoal per day, besides making available up to 0.84 of thermal power in the residual gases. For converting the gases’ energy into electricity, two technologies were analyzed: a conventional steam Rankine cycle and an Organic Rankine Cycle (ORC), which presented efficiencies of 25.8% and 26.3%, respectively. The economic analysis indicated the Organic Rankine Cycle as the most viable technology for the case under study, where it is estimated a specific generation of 240 kWh per ton of charcoal, considering a gravimetric yield of 33%. The analysis also considered a charcoal gravimetric yield of 42%, which resulted in a specific electricity production of 165 kWh per ton of charcoal. Continuous carbonization technology proves to be quite effective for large-scale charcoal production in Brazil. In addition to producing better quality and more homogeneous charcoal, it manages to provide the full use of the energy contained in the wood with the generation of electric energy through the surplus gases of the process. The emission of highly polluting gases, such as CH4 and CO, is eradicated with the burning of the residual gases, thus avoiding one of the greatest problems of this industrial sector, the emissions of greenhouse gases.

Small Hydroelectric Plants (SHPs) make up 3.3% of the Brazilian electricity grid, and are
becoming more popular given their lower environmental impacts compared to larger
hydroelectric plants. The energy generated by SHPs is sold using a Physical Energy Guarantee, also known as a Power Purchase Agreement (PPA), which is the maximum amount of energy that a generator can sell. The PPA is calculated based on monthly average flow series data, however, studies have shown that this can overestimate the PPA, and that daily average flow series data are more accurate in reflecting the amount of generated electric energy. Unlike other hydrological evaluations, the uncertainty levels associated with the data used to calculate the PPA at SHPs are neither considered nor quantified. This study investigates the impact of hydrological uncertainties on SHP PPAs. The Monte Carlo method was used to analyze the uncertainty levels for an SHP case-study. The results showed that the PPA, in optimistic and pessimistic scenarios, was higher than the current PPA. Dispersion analysis revealed that SHPs with smaller installed capacities and lower PPAs faced more business risks, compared to SHPs with higher PPAs, which are generally more thoroughly evaluated by investors. It was verified that once the adhesion of the SHPs to the Energy Reallocation Mechanism (ERM) is optional, the analysis of the uncertainty margins of the PPA has the possibility of allowing the generator to have an additional mechanism for analysis and decision making regarding the adhesion or not to the ERM. With the uncertainty margins it is possible to compare if the value attributed by the Ministry of Mines and Energy is within the delimited margins, as well as allow the entrepreneur to evaluate in probabilistic terms the real generation conditions of its plant and the risks to be faced in terms of energy trading.

In the search for energy sources that have lower environmental impacts, there is also the need to dispose of waste generated by human activities. In this context, a holistic analysis of the energy use of residues from agricultural and forestry activities, animal excreta, urban solid waste and sewage, from the pulp and paper industry and charcoal in Brazil is presented. Based on a bibliographic review, the current Brazilian panorama is presented in figures that contribute to a vision of the national potential for harnessing bioenergy from its theoretical and technical potential. The QGIS3.24.2 Tisler geoprocessing tool was used to generate potentiality maps from census data of microregions and municipalities available in the IBGE database (2022) and the Geocentric Reference System for the Americas (SIRGAS 2000). The results of the analysis of the maps by micro-region of generation potential from agricultural residues highlight the cultures of sugar cane, corn and soy. The greatest technical potential for generation from biomass residues is found in the agricultural segment, with 53.3 GW of technical potential. In this segment, sugarcane (32.5 GW potential), corn and soybeans (both with 7.8 GW of technical potential) stand out. In addition, sewage sludge (12.2 GW) and animal excreta (6.8 GW) have promising technical potential. In aggregate, it is concluded that Brazil has a technical potential of 12,184 PJ/year of generation from biomass residues, which is equivalent to an installed power of just over 126 GW from this type of source. Currently, Brazil has only 16 GW of installed power for the energy use of biomass, basically exploiting sugarcane residues and black liquor. 

The investigation was developed to study the conversion of nitrogen into its byproducts, particularly focusing on NH3 formation. The study involved pyrolysis and gasification experiments using nitrogen-rich animal residues as biomass, along with an assessment of integrating this process into the Brazilian scenario to evaluate the potential increase in ammonia production. Additionally, a preliminary Computational Fluid Dynamics (CFD) model was developed to analyze the inert bed's characteristics under both cold and hot conditions, comparing the resulting gas with experimental data. The experimental methodology involved segmenting the thermochemical gasification process into sequential subprocesses of pyrolysis and gasification. Pyrolysis was conducted in fixed and fluidized bed reactors using raw biomass, while gasification experiments used the char originated from the pyrolysis experiment and only the fluidized bed reactor was used with different gasification agent mixtures, including steam. The results showed distinct nitrogen-to-NH3 conversion rates in the different stages of gasification, with the pyrolysis stage contributing approximately 49.3% to the direct NH3 conversion, while gasification of nitrogenated char accounted for 4.5% of the total conversion. The study's applicability to the Brazilian context involved two analyses: the country's fertilizer consumption demand, heavily reliant on imports, and the potential use of animal carcasses (26 million tons annually) to produce meat and bone meal (MBM) for NH3 production. Utilizing approximately 2,2 million tons of nitrogen from MBM could generate around 1,5 million tons of ammonia annually, representing a substantial reduction in costs (7 to 7,5 billion reais) and meeting nearly 80% of the National Fertilizer Plan's nitrogen fertilizer production goal. The CFD model's development occurred in three stages: adapting the fluidized bed reactor's geometry, configuring the hydrodynamics model (cold bed), and implementing the reactive model (hot bed) with species transport and chemical reactions. The model demonstrated good performance in predicting NH3 production, but improvements are necessary to consider additional chemical reactions and reactive models for species transport. Experimental validation showed promising results for NH3 prediction, but discrepancies were observed for CO, mainly attributed to gasification agent dilution. Overall, the study provides valuable insights into the conversion of nitrogen-rich biomass into NH3 and the potential implications for ammonia production in the Brazilian context. The CFD model shows promise but requires further refinement for accurate prediction of gas composition.

In the pursuit of sustainable energy solutions, the transition to a low-carbon economy has become a central objective for countries worldwide. This work presents a comprehensive technical, economic, and environmental analysis of the use of green hydrogen to enhance methane production in biodigestion systems. Situated within the broader context of renewable energy adoption and the drive for decarbonization, with a particular focus on Brazil's energy matrix, which already incorporates a significant share of renewable sources.
The rationale behind this research is anchored in the critical role that biogas, especially methane, plays in the renewable energy landscape. Biogas production from agricultural waste not only provides a pathway for waste valorization but also contributes to energy security and environmental sustainability. However, the methane yield from conventional biodigestion processes often fails to reach the expected potential. The introduction of green hydrogen into biodigestion systems emerges as an innovative strategy to overcome this limitation, promising to enhance methane production and enrich the energy value of biogas.
The primary objective of this dissertation was to explore the feasibility and sustainability of integrating green hydrogen into biodigestion processes for methane enrichment. This objective was pursued through the evaluation of eight alternative pathways incorporating Power to Gas (P2G) technology, focusing on their technical performance, economic viability, and environmental impacts. The study specifically aimed to optimize biogas production from swine residues and elephant grass, considering their abundance and energy potential.
Adopting a methodological framework that combines theoretical analysis with simulation tools, the research utilized Life Cycle Assessment (LCA) and SimaPro® software to systematically assess the environmental footprint of each proposed alternative. Economic analysis was based on production cost estimates, potential revenues, and overall economic viability. Technical evaluation focused on the efficiency of hydrogen integration into the biodigestion process and its impact on methane yield.
The results of this research revealed promising prospects for improving methane production through the synergistic use of green hydrogen. The explored alternatives demonstrated varying degrees of effectiveness in increasing methane content, with specific pathways showing significant potential for the sustainable upgrading of biogas. In scenarios where co-digestion was employed, higher energy results were obtained due to the use of grass silage, increasing biogas yield to 121.54 m³/ton. However, the economic analysis yielded less favorable results due to transportation costs and the quantity of hydrogen used. Economic analysis underscored the importance of supportive policies and technological advancements in improving the cost-effectiveness of these solutions.
In conclusion, this dissertation posits that the integration of green hydrogen into biodigestion systems represents a viable and innovative approach to increasing methane production. This strategy not only aligns with environmental sustainability goals but also has the potential to strengthen the contribution of the renewable energy sector to the energy matrix. The implications of the study extend beyond technical and economic realms, highlighting the role of policy frameworks, market mechanisms, and research and development in facilitating the adoption of green hydrogen technologies. Looking to the future, the research identifies several avenues for future investigations, including exploring further.

This study focuses on the Brazilian energy scenario and highlights the progressive increase in the use of renewable sources in the country's electrical energy matrix. The main objective of this study is to contribute to the search for solutions and encourage debates and reflections on the future actions necessary for energy planning. To achieve this, the research employs computational tools based on machine learning and data mining, using government and energy market data sources. The research methodology begins with the analysis of historical data related to the electricity market in Brazil, including policies, national guidelines and regulatory mechanisms. The research then uses machine learning and data mining tools to forecast the electricity market in the country. These forecasts are then compared with the horizon predicted by the Ten-Year Energy Expansion Plan 2030. The methodology used includes the execution of forecast models, highlighting the behavior of the energy market over time, using three different methods: Multilayer Neural Networks Perceptron (MLP), Gaussian Process Regression (GPR) and Linear Regression to project electrical generation by source in Brazil. The results indicate considerable growth in renewable sources in the national energy market until 2030, approaching the objective of the Ten-Year Energy Expansion Plan of reaching 90% renewability, covering sources such as hydroelectric, biomass, wind and solar. The Linear Regression method achieves 86% renewability, while the Gaussian Process Regression method achieves 90%, and the Multilayer Perceptron Neural Networks method reaches 88%. Likewise, the scenarios proposed for the Brazilian energy market intended to gradually increase the use of renewable sources in the electrical energy matrix and its growth potential. The projection of the electricity market forecast made it possible to identify market behavior patterns, allowing trends and changes in the market to be anticipated. These forecasts are intended to provide information to support the development of actions in the energy planning process, contributing to the transition to more sustainable and renewable sources of energy in Brazil.

Currently, many water supply systems collect and monitor data daily, among which we can highlight values of reservoir levels, pressures, demands, in addition to electrical consumption data. The generated data becomes information providing the necessary knowledge to direct the manager to carry out actions and decision-making in general. In addition, R is a software widely used for statistical analysis and recently in some works, a functionality of R coupling to Epanet was presented, such as: ARANDIA and ECK (2018), MACEDO (2020) and BARBEDO (2021) fact that facilitates the analysis of various hydraulic scenarios. Thus, this dissertation aims to evaluate the potential use of R and Epanet in a database of water supply systems, for this purpose it was considered for the methodology to propose a theoretical water distribution network and evaluate scenarios simulation and the results from R.After coupling, the proposed network was simulated with the variation of the reservoir level and demands in several different scenarios, thus obtaining several results. It was possible to automate the analysis process, generating graphical tables and statistical data regarding the dispersion of demands, pressures and flows resulting in the nodes and in the stretches from each demand variation and reservoir levels that were stored. The results obtained proved the compatibility and practicality of the mathematical model of water distribution designed in the Epanet software simulated in the R software.

Since prehistoric period, man has used intelligence to create mechanisms that reduce effort and increase comfort. By mastering the fire technique, he improved his food, lighting and security. He discovered the power of the waters, the winds and tamed animals, using the strength of horses and oxen for work. Thousands of years passed until a fact marked the history of energy: the invention of the steam engine, an energetic symbol of the Industrial Revolution. It was just over 100 years ago that electrical energy emerged, symbol of the Information Age. Through it, other forms of energy could be transformed efficiently, such as: heat, lighting and mechanical energy. Electricity is something special for the development of activities, but in view of the scarcity of natural energy resources and the increase in consumers resulting in price increases, the conscious use of energy is increasingly encouraged, seeking alternatives to improve quality. and efficiency of the energy to be supplied. With the increase in technology, and increase in consumers, the concern about the energy efficiency of the energy distribution system grows, with a view to the quality of supply and economy in the sector for the year 2029, an energy saving of 23, is expected. 1 million tons of oil equivalent, of which 16% corresponds to electricity savings and 84% to fuel savings, around 10% higher than those foreseen in the PDE 2029, in order to adequately deal with the implementation risks. For electricity savings in the year 2029, the industrial sector represents about 35% of the total, followed by the residential and commercial and public buildings sectors, which represent 20% and 16% of the total, respectively. The service sector, including the public lighting and sanitation sectors, but without the participation of commercial and public buildings, represents approximately 21% of the total. In this context, the general objective of this work is to analyze the considerations of the PEDF together with the PDE 2029 considering the guidelines, studies and uncertainties, practical application in an industrial environment, showing the energy gain, where a lighting Retrofit with reduction of the consumption, generating economic gain as a result of energy efficiency, which consists of changing from less efficient to more efficient lighting, considering the replacement depending on the areas, changing IP67 closed hermetic luminaires and changing lamps to LED, generating a total reduction of approximately 25% of the system power with reduced maintenance cost and risk reduction.

With the global increase in energy demand and global concern with climate change on the planet, incentives for research and development of biofuel production processes, such as ethanol, have grown in recent decades, aiming at the full use of biomass and the minimum generation of waste. In order to make possible the implementation of 2G technology in Brazilian 1G biorefineries, studies with economic and environmental assessments are essential to identify possible procedural bottlenecks and help in decision-making. Thus, the main objective of this work was to carry out a technical-economic analysis (TEA) and life cycle assessment (LCA) of ethanol production in a biorefinery that integrates 1G and 2G technology from sugarcane and its waste. For this, three scenarios were evaluated: Scenario I which represents an autonomous Brazilian distillery, while Scenarios II and III present an integrated 1G2G technology addressing different types of pre-treatment (acid and hydrothermal) and using recombinant yeast in the fermentation step. Scenario simulations were performed using the EMSO software, while the LCA was performed using the SimaPro® software. The integrated process increased ethanol production by 14% in Scenario II and 16% in Scenario III compared to Scenario I. The integrated processes (Scenarios II and III) had high production costs, resulting in a minimum selling price of ethanol greater than the marketed value of ethanol around 31% for Scenario II (693.59 US$/m³) and 48% for Scenario III (785.47 US$/m³), which made the processes unfeasible from the point of view economic. In the environmental analysis, both Scenarios did not have the necessary potential to mitigate the environmental impacts of the 1G2G ethanol production process in relation to Scenario I, in order to obtain all categories of environmental impact lower or close to Scenario I. The obtained results indicated the need to select other ethanol production processes as a way to improve the integration of processes in sugarcane-based biorefineries.

An increase in the demand for sustainable electricity generation can be seen as the knowledge about the human influence on global warming expands associated with an increase in the world electricity demand. This characterizes the energy transition, seeking to reduce both environmental impacts and fossil fuels use, while keeping the energy security. It is relatively easy to transport and transform the electrical form of energy, but there is still a lack of access to electricity in many regions around the world. In this context, the development of hydrokinetic turbines can be valuable. This type of turbine transforms the kinetic energy of a river or ocean water flow into shaft power, that starts a generator. In contrast to conventional hydraulic turbomachines, these turbines do not require dams, as they are free flow turbines.
To define strategies for the study of hydrokinetic turbines, the steps for classification in Technology Readiness Levels are proposed. This management tool is often used with the aim of technical validation and cost reduction in engineering projects. One study case was also carried out. Numerical modeling was conducted to study a hydrokinetic turbine operating in tidal regime, with flow in two opposite orientations intermittently. The ANSYS CFX® software was used to numerically solve local and global quantities that were used to analyze the blade project influence on the machine efficiency with a computational fluid dynamics approach.
Hydrokinetic turbines can be used in small systems for electrification of villages or in farms with many turbines to achieve a higher installed power. In the first example, costs are limiting in the projects, while for large systems the efficiency usually defines the viability. The challenges for sustainable electricity generation increase the opportunities for development of new hydrokinetic turbines market. That can be beneficial to Brazil, the country already has a large participation of renewable sources for electricity generation but has challenges to keep this attribute. Hydrokinetic turbines are not a completely consolidated technology, therefore there is an opportunity for the development of new turbine models.

Electricity is essential for the daily activities development; therefore, the concessionaires must provide it with quality to their consumers, following the standards and requirements of the Regulatory Agency. However, even if this is done, disturbances in the electrical network may occur, causing damage to consumers' electrical equipment, emphasizing that current equipment is more sensitive to electrical disturbances. In addition, if the damage happens, the consumer has the right to request reimbursement, according to the procedure of the regulatory agency and its concessionaire, in accordance with Module 9 of Procedure for the Distribution of Electricity in the National Electric System (PRODIST) in the National Electric System and REN 414/2010. Even after the technological advances in electronic equipment, and the Information Technology dissemination, Module 9 has not yet undergone any revision, since it came into effect in 2012. In this context, the study provides an overview of the procedures for reimbursing electrical damages in Brazil and other countries, in order to present possible suggestions for changes, certain a better relationship between concessionaires, consumers and the regulatory agency. Among the results obtained there is a suggestion for the standard report to have minimal information regarding the damage and the affected equipment, which would help in reducing fraud, with the insertion of the equipment's supportability curve in its technical manuals. Another possible change is the reduction of the deadline for requesting reimbursement or the time of timeliness, which contributed to finding the cause of the problem. The depreciation criterion application with no value to be reimbursed may even be considered fair for a distributor, who will pay the value of the product considering the time of use and its natural wear and tear, but for the consumer it may not be interesting and viable. The installation of Surge Protection Devices, according to the tests carried out in laboratories, results in good results, protecting the equipment against burning. It is important to proceed with improvements so that the requesting reimbursement process for electrical damages results in benefits, both for consumers who can be reimbursed, in case any damage has occurred in their equipment, as well as for the distributor in the improved analysis of these damage recovery processes.

The growth in bovine and swine productivity is the result of the modernization of intensive confinement production systems. However, the accumulation of waste, in the absence of sanitation, impacts the environment and favors the proliferation of diseases. The objective of the present work was to carry out a theoretical study of the energy utilization of biogas from the co-digestion of bovine and swine manure in anaerobic digesters, converting an environmental liability into a source of clean energy and production of digested organic matter, a natural biofertilizer. The mixture of two or more types of substrates aims to optimize the functionality of anaerobic digesters in the qualitative and quantitative aspects, providing continuous processes for the production of biogas. The analysis was made using theoretical data from the literature of daily production of manure per animal in which the best quantitative methane generation was the ratio of 4 parts of cattle manure to 1 part of pig manure. After analyzing the biogas production of the substrate, a technical and economic feasibility study was carried out using the investment projection tools Net Present Value (NPV), Internal Rate of Return (IRR) and Levelized Energy Cost (LCOE), as well as the mapping of the identified codigestion potential and the study of avoided emissions of Greenhouse Gases (GHG) associated with this application. The results showed that enterprises of biogas plants resulting from the co-management of manure become viable from 1,410 heads of cattle and 2,350 heads of pigs. This quantity of animals and proportion of waste results in a methane flow of 163,41 m³ ∙ d-1, which corresponds to an energy potential of 128 MWh ∙ year-1, classifying the project as distributed microgeneration according to the resolutions of the National Electric Energy Agency No. 482 / 2012 and No. 687/2015. The present study showed that biodigesters are important sanitation mechanisms for rural areas and agro-industry, improving living conditions and adding value to the agribusiness production chain.

This study evaluates the potential of available land areas for bioenergy production in 2050 without compromising food security limits. The estimates contain the global population food demand, the agricultural production supply, the availability of surplus land that could be used for biofuels production, and the bioenergy production potential in the remaining area. The novelty of this article is the qualitative and quantitative evaluation of the parameters that influence the availability of land for bioenergy production. Unlike previous studies, the work also considers food waste in projections, the degraded land area, in addition to parameters that are often disregarded by other authors, such as urban agriculture and the consumption of insect proteins. The projections were made for 3 different scenarios: business as usual (C1), the best of realistic scenarios (C2), and the theoretical situation (C3). The projections disregard the economic and market influences that govern the distribution and use of land. The current excessive consumption and the impacts of human activities are responsible for the reduction in the available land area for bioenergy, while the application of disruptive technologies is the main factor of increase. There will be enough arable land to feed the world population in 2050 in the three proposed scenarios. However, even choosing to prioritize the preservation of forests, and going to shrubland as the next agricultural frontier, the arable land available for new bioenergy projects could be limited in C1, and it would be necessary to deforest 24% of the forests area (935 Mha). In C2, 5,7% of arable land would remain available to produce bioenergy, reaching 92% of the carbon sequestration target. And in C3, 42% of arable land could produce bioenergy to sequester more than 6 times the amount of carbon stipulated for 2100. The parameters with the greatest opportunities for gains, for quantitative reasons and technical feasibility of action, are food waste, low productivity due to land degradation, increases in productivity due to technological gain, and reduction in the consumption of animal proteins, especially from roaring animals. The potential participation of bioenergy in the global energy matrix is relevant even for C1, at 7.5%, with 64 EJ. In the best of realistic scenarios, C2, bioenergy could represent 21.0% of global energy production, with 178 EJ, while the energy crops could produce 31 times bigger than today. The results of the global bioenergy potential obtained in the projections of the most realistic scenarios, C1 and C2, were close to each other and other studies in the bibliography. In the theoretical situation, C3, bioenergy could supply almost two and a half times the total global demand for primary energy in 2050.

The present work collects general information on the main operating parameters in BFBG and presents a discussion of the influence of the operating parameters on the generated gas. Considering the main process characteristics, was described and analyzed the hydrodynamic performance of a new equipment of BFBG laboratory-scale operating at atmospheric pressure. For this purpose, technical details of the facility and materials used are presented, subsequently, fluidization tests at different temperatures are performed, aiming to compare with the main mathematical models available in the literature that describe the physical characteristics of the bed. The tests were performed using Electrofused Alumina Oxide (High-Alumina) as bed material and air as a fluidizing agent. The results indicate that homogeneous fluidization occurs at velocities greater than 1.7 times the minimum fluidization velocity. The physical characteristics of the bubbles agree with the models proposed in the literature, and the formation, growth, coalescence, and eruption of bubbles are concentrated near the reactor walls. Increasing the fluidization velocity increases the coalescence of the bubbles, this gives rise to larger eruptions that may favor mixing of the fuel with the bed material.

Researches in Hydro Power estimation costs are extremely complex because are many parameters that must be analyzed, such as the location of the project, considering the prices of construction inputs, as well the physical characteristics where the Hydro Power is built, changing accord region.
Besides, the energy market oscillations, as well the local and world economy interference, affect directly the Hydro Power costs, so a better knowledge about the costs behavior minimizes the aggregate errors in the estimative to decision takes.
In this way, the present study shows a model of estimation cost based on costs’ information of several hydropower plants in Brazil and worldwide analysis, bringing up the technological cost concept to the modeling, representing the generator group manufacturing cost, excluding the commodities costs.
Technological cost is the difference between group generator’s providers since a cost composition of a component be composed by the combination of direct and indirect costs, technological production costs and commodities costs, the last one in larger relevance to steel and cooper to the present study.

The use of the potential energy embedded in water supply systems through Pumps as Turbines (PATs) is an alternative that has been showing technical and economic viability due to the reduced cost of the pumps used. However, the system implementation may become economically unviable due to low potential energy available at each point and the need to project on-site infrastructure. In order to ease of maintenance, safety and guarantee of the pressure established in technical standards it is necessary to contain equipment such as drawer, filter, water meter and Pressure Reducing Valve (PRV) registers in a by-pass system contained in a protection box, which can lead to higher deployment costs. In view of the referenced problems, this paper proposes to analyze the economic feasibility for the installation of BFT and its attached equipment, considering the available potential energy, the present infrastructure, the installation cost and the future energy generation for each section studied. This analysis will be performed by calculating the Net Present Value (NPV), Internal Rate of Return (IRR), Levelized Cost of Electricity (LCOE) and payback, measuring three scenarios with different infrastructure levels on site. The ideal scenario, that considers the existence of the entire infrastructure, obtained the result of R$ 7,251.17 (NPV), 21% of IRR, R$ 0.55/kWh levelized cost of electricity and approximately payback in six years, with power generation range of 0.11 kW up to 0.32 kW and annual generation of 1,772,81 kWh. The scenario that only presents civil works as existing infrastructure did not present deployment feasibility, resulting in a R$ 12,653.10 demage, 2% of IRR and Leveled Cost os Energy os R$ 1.58/kWh. The real scenario, which depends on the installation of the entire infrastructure, also did not present deployment feasibility, resulting in a R$ 22,714.19 damage, -1% of IRR and R$2.10/kWh Levelized Cost of Electricity (LCOE).

In the last decades, energy systems have been undergoing a transition process, due to technological innovations resulting from the expansion of renewable sources, seeking to minimize the use of fossil fuel technologies in energy systems for a low carbon economy. This transaction requires political and regulatory attention, and poses challenges to public policy makers. One of the main concerns concerns the rapid diffusion of distributed generation (GD), particularly distributed photovoltaic generation (GDFV), which can interfere in the financial sustainability of Electricity Distributors (DEEs) and impact the reliability of the power systems. This diffusion causes more consumers to adopt PVDG and generate their own energy, causing decrease in revenue of power distribution utilities. That may trigger a phenomenon called “death spiral" of utilities. In this context, this study aims to improve an Agent-Based Model (ABM) to explore the diffusion of PVDG in the Brazilian context analyzing in which extent that diffusion could reduce the utilities revenue, thus triggering the "death spiral". The study also addresses issues related to the energy transition, from a point of view that allows evaluating the situation more broadly. The model shows that concerns about the “death spiral” due to the adoption of PVDG, under the policies, tariff structure and form of compensation for electricity in the country are relevant and deserve attention. It has been found, in a consistent manner for the scenarios and cases analyzed, that the scale of diffusion of PVDG is significant, in terms of supply of electricity generation using solar energy, reduction of revenue and subsequent tariff increases. However, the adoption rate occurs more smoothly than suddenly, giving time and a certain flexibility so that the power distribution utilities and regulators adapt to the diffusion of this disruptive technology. Finally, the results of this research suggest that the concern with the “death spiral”, which falls on the power distribution utilities, through the diffusion of PVDG, has no force, when there is no tariff review that takes into account the reduction in the number of consumers. This shows that regulators must monitor the diffusion of this technology in order to analyze the revenue losses of power distributors and concentrate their work on future tariff innovations.
 
 

This thesis includes the feasibility study, technical and economical, of a new power generation system that combines two technologies: Gas Microturbines GMT and Biomass Gasifiers. The response of a microturbine to gas with nominal power of 200 kW being fed with synthesis gas is studied; two specific types of gasifier are analyzed: Downdraft Gasifier DG and Dual Fluidized-Bed Gasifier DFBG, both operating with a reference biomass (wood pellets) and using different gasification agents (air, steam, oxygen and mixtures thereof). Finally, the behavior of both technologies when coupled is validated through simulation. The delivered electric power ranges from 52.51 kW to 56.73 kW depending on the type of gasifier and the gasification agent used. The overall efficiency of the arrangement may vary between 4.64 and 11.01%. From the economic assessment, none of the technically possible systems is viable.
 

In Brazil, electricity supply is considered an essential service that all citizens are entitled to. Historically, when investigating the electrification process in the country, it is possible to identify that the highest rates of electrical exclusion are characteristic of the rural area, since, for decades, the national energy sector has prioritized the centralized production of electricity to serve the large consumption concentrations. In order to universalize this service, several policies have been developed as strategies to allow access to these regions to have technical and economic viability. In this sense, alternative energy sources, in particular photovoltaic solar energy, have increasingly been considered a viable option that contributes to the development of the rural area, either by providing access to electricity in homes or as a source of energy supplement to be used in economic activities practiced in the region. However, it is still possible to identify several challenges that prevent the source from being one of the important items for rural progress. In this sense, the present study aims to identify some barriers and benefits from the use of technology applied to rural areas in the state of Ceará. The methodology is based on qualitative and quantitative research, since it brought a bibliographic approach, data collection, through forms, and a case study. As a result, it was found that Ceará has numerous potentials (solar, institutional, productive resources) for using the source in the rural area. However, some barriers determine the low rates of technology adoption. The difficulties faced are a consequence of the economic aspect, lack of planning, non-observance of the characteristics and needs of the target audience, lack of knowledge and dialogue between the actors, among others, and imply failures in the installation, operation and sustainability of the systems.
 

The present work studies the gasification process of oily sludge from the refining and storage petroleum process, through a computer modeling that considers the chemical equilibrium and whose objective is to evaluate the production of producer gas and its potential use for electricity generation. For this purpose, four scenarios were considered for the thermochemical conversion of oily sludge, which differs in the gasification agent used, being air for scenario 1 (C1), oxygen for scenario 2 (C2), air/steam mixture for scenario 3 (C3) and oxygen/steam mixture for (C4).
The results showed that the composition of the producer gas had the same behavior for C1, C2, and C3, with the molar fractions of CO and H2 increasing with the increase of equivalence ratio (ER) until reaching a maximum value and then decreased. In the case of C4 for all steam to oily sludge ratio (SOR) values analyzed, H2 decreased, CO remained constant and CH4 was almost zero for the whole range of RE studied. For a range of ER between 0.25 and 0.45, the producer gas yield increased from 0.81 to 1.15 Nm3/kg oily sludge for C1, from 0.59 to 0.67 Nm3/kg oily sludge for C2 and for mixtures with steam (C3 and C4) the highest yields were obtained for the SOR of 1.5. Meanwhile, the lower heating value (LHV) decreased when the ER increased from 0.25 to 0.45, from 5.69 to 3.44 MJ/Nm3 for C1, for C2 the change was from 8.64 to 6.81 MJ/Nm3, in C3 varied from 4.79 to 3.17 MJ/Nm3 and for C4 from 6.97 to 5.98 MJ/Nm3 (SOR=0.5).
The producer gases obtained in the four scenarios were fed to three prime movers (internal combustion engine, gas microturbine, and steam cycle) for electric generation. The internal combustion engine was the one that produced the highest electric power, being possible to obtain powers in the range between 335 and 183 kW when the producer gas obtained in the C4 with a SOR of 0.5 was used, while the gas microturbine has higher technical requirements to be operated with producer gas. Based on the properties of the producer gas, it is verified that oily sludge gasification could be a viable alternative for the treatment and energetic use of this residue.

This study explores different scenarios for the Brazilian Pre-Salt oil production and its associated impact in the Brazilian petroleum market. For the retrospective analysis, two alternative scenarios show how important oil production from the Pre-Salt reservoirs was in the last decade. For the prospective analysis, this study outlines an envelope for the Brazilian Pre-Salt results in the next ten years based on five scenarios with different combinations of quantitative factors (oil production, oil demand, and oil price), as well as qualitative factors (regulatory and environmental restrictions), in the post-pandemic environment. Oil is the main energy resource for both production and consumption matrices in Brazil. The Brazilian Pre-Salt reservoirs are already responsible for most of the national oil production and nearly all the oil production expansion forecasted for the next decade. Considered since its discovery one of the most promising oil provinces in the world, the Brazilian Pre-Salt faced some regulatory restrictions that delayed its development in the first half of the last decade. Despite regulation improvements made lately, its exploration will face further challenges due to the oil market crisis and economic recession caused by the Covid-19 pandemic. However, the results of the study show that, for the period between 2020 and 2029, oil production will remain higher than oil demand. The excess of oil production shall guarantee trade balance surplus for oil and oil derivatives, even in the worst-case scenario, despite initial restrictions and the possible effect of the post-pandemic crisis

Over the years, the electric sector has gone through many changes. Among these changes, and the most relevant change is that of the government’s participation in the sector, going from proprietary role into one that is focused more on regulatory aspects. The tariffs relative to electric energy have been directly affected by charges created by the federal government as defined by resolutions from the National Electric Energy Agency – ANEEL, as well as federal and state taxes. This tariff has undergone changes to its value over the years due to the definitions to the charges and their changes, as well as changes to tax legislation where in many cases the tax rates were raised. The manner in which they can affect consumer rates with the Regulated Contracting Environment (ACR) was analyzed with the objective to show how sector charges and taxes impact electric energy tariffs. To develop this work, a diverse set of data was collected on billable revenues from electric energy supply on a national scope, with and without taxes, relative to the ACR. Electric energy distributors participation with this revenue was also analyzed by dividing them into the geographical regions in Brazil they operate. The evolution of the average tariff was considered and compared to the influence of economic indexes. This impact was analyzed along the years with regards to the sectorial charges and taxes with concern to the value of the tariffs, and how this affects the final price for energy for consumers in this contracting environment. With a more specific case study, information from an electric energy distributor, who has operated greatly in the market, was used. This includes information such as samples from its revenue, incidental taxes on said revenue and sectorial tariffs, having the aim of analyzing the impact it caused and paid by the final consumer. Thus, one can see how sectorial charges and taxes impact the final consumer’s bill for electric power in the ACR (in this specific case a residential consumer in the state of Minas Gerais, Brazil). It was found that a significant portion of this bill is comprised of sectorial tariffs, as well as PIS, COFINS and ICMS (taxes on the supply of electric energy). In fact, of their bill, the consumer who was analyzed pays approximately 50% in sectorial taxes and tariffs designated for specific purposes such as: the guarantee of an electric energy reserve; provide financial support for activities by ANEEL and ONS; investment in Research and Development on electric energy; and the Energy Efficiency Program in the country, among others.

The work proposed in this dissertation shows the procedures for dimensioning, construction and testing of an energy converter that combines concentrated heliothermic technology (CSP) associated with thermoelectric coolers (TEC) in order to convert thermal energy into electrical energy directly following the Seebeck principle without the need for conventional electrical energy transformation equipment such as conventional electric turbines and generators. The use of thermoelectric coolers (TEC) to convert thermal energy from concentrated sunlight into electrical energy is still little explored, making this work a pioneer, opening a new line of research in solar energy conversion systems. . For testing, two field-tested prototypes were built. The efficiency ratio presented between the two solar concentration systems, designed, built and tested by the author, proved to be promising since the results obtained in bench tests were satisfactory, which allowed to verify the operational viability of the proposed system.

Crude Palm Oil (OCP) is the largest vegetable oil produced in the world. In 2019, OCP production was 72.3 million tons per year (35.45% of the mass of total vegetable oil produced in the world), followed by soybeans with 56.8 million tons per year, and rapeseed oil with 27.5 million tons per year. However, in recent years, due to the presence of diseases, plantations of the Híbrido InterespecíficoO×G, a cross between the American palm and the African palm, increased substantially in Latin America because of its tolerance to the bud rot disease caused by Phytophthora palmivora. As a result, the key objective of this research was to evaluate and compare the energy balance and the biodiesel production chain from the E. guineensis Jacq palm genotypes and Híbrido Interespecífico(OxG), or the current agro-industrial situation in Colombia. For such purposes, an energy analysis was carried out and performance indicators of the 1st law of thermodynamics were calculated to determine the way in which energy is used in each process, as well as the potential for using palm energy per hectare. Therefore, a comparative “cradle-to-gate” analysis was carried out to verify the environmental performance of the genotypes in question. The functional unit was defined as 1.0 MJ of energy produced, and the impacts were modeled using the software package SimaPro v.8.0.3 (Pre Consultants) and quantified using the Impact 2002 + method. The results obtained from the thermodynamic analysis show a 6.2% reduction in the overall efficiency of the system, when compared with the biodiesel from E. guineensis Jacq., Nonetheless, the potential for improvement that biofuels production has from the Híbrido Interespecífico(OxG) genotype, specifically in the oil extraction stage, due to the current inefficiency existing in the mechanical subsystems (sterilization, separation, pressing, crushing, etc.) it is more than 4% in energy productivity per hectare. CO2eq emissions from the biodiesel life cycle based on traditional fruit was 12.5 g MJBD-1, not counting carbon sequestration. In comparison, the CO2eq emissions of biodiesel produced by the hybrid fruit was 13.8 g MJBD-1 . For these facts, the efficiency indicators of the life cycle of biodiesel produced by hybrid fruit showed lower values than those of conventional biodiesel, reductions of 26.9% and 19.7% in NERTotal and FER, respectively. Nevertheless, when compared with the biodiesel production of other palm researches, a better energy use of up to 1.2 energy units is observed, as well as a greater renewability of up to 3 energy units. Thus, this article concludes that the Híbrido Interespecífico(OxG) genotype has a latent potential for the production of energy, fuels and food, with low environmental impact.

Considering the importance of biodiesel production in Brazil, especially with the increase of the obligatory biodiesel blending to diesel, this work aims at comparing the production of biodiesel from two raw materials available in the country, through the three production routes different. The Life Cycle Assessment (LCA) was the methodology used for this study covering the stages of obtaining the raw material until the production of biodiesel, an approach called "Cradle to Gate". Six scenarios were determined from soybean and palm raw materials using three technological routes: homogeneous transesterification, heterogeneous transesterification and enzymatic transesterification. A functional unit of 1 MJ was established using the software SimaPro 7.0 ® and the method of evaluation of the environmental impacts adopted was IMPACT 2002+. An indicator was calculated to characterize the biodiesel renewal, in addition, the Cumulative Energy Demand method was used to calculate the energy efficiency of the biodiesel life cycle (LCEE). All scenarios are energy efficient and have positive values indicating biofuel renewal. The scenario of the heterogeneous transesterification of palm oil has the best performance for both indicators. Among the raw materials, the results indicated soybean with greater environmental impacts. For soybean biodiesel the stages with the greatest contribution are the cultivation stage due to the higher emissions due to the consumption of fertilizers and fossil fuels and the stage of extraction of the oil by the use of chemical solvent. For the palm the stages of cultivation and transesterification are highlighted, mainly by the production and use of steam. Homogeneous transesterification had the greatest impact in 9 of the 15 categories of environmental impacts evaluated, as well as in 3 of the 4 categories of   environmental damages. The production of biodiesel via heterogeneous transesterification from palm oil presented the best performance.
 
 

The growth of renewable sources of energy, considered as intermittent sources, has raised the issue of energy storage as a way to guarantee the reliability of the energy system and to meet the growing demand of the various countries around the world. Among the forms of energy storage, Pumped Hydropower Energy Storage (PHES) have been gaining prominence due to their technological maturity and great capacity to meet demand at peak times. The objective of this work is to prepare a checklist of the environmental impacts of PHES and to develop a quantitative methodology to evaluate these impacts. For this, a bibliographic review was done in the national and international literature, listing all the environmental impacts resulting from the PHES, in the physical, biotic, anthropic and legislative environments. At first, with this impacts’ list, a questionnaire was developed, applied to postgraduate students in Energy Engineering at UNIFEI, where weights were assigned for each impact. Secondly, the same students evaluated the same impacts, assigning grades from 0 to 1, but within the context of the Curuá-Una case study. At the end, the notes were compiled with their respective weights and the average grade for the PHES proposed by the case study was obtained. The results showed that the biotic environment would be the most affected, and that there is a need for deeper analysis of the positive and negative impacts of the enterprise, in order to justify its implementation.

Nowadays, the transition from conventional fossil fuel based on centralized energy generation to distributed renewables is increasing rapidly due to environmental concerns and political incentives. Wind and solar power generation offer carbon dioxide neutral electricity but also present some integration difficulties for energy system operators and planners due to intermittent power output. A promising way of dealing with the intermittency from renewables is energy storage. Many types of energy storage have been under development and study. Therefore, a battery energy storage system has been implemented mainly in residential applications to utility power grids. Battery energy storage can allow higher amounts of renewable electricity generation to be integrated by smoothing power output and time shifting generated energy to follow demand and increase hosting capacities through peak shaving. Power quality related issues due to intermittency can be mitigated by controlling the storage’s charging patterns to respond to grid variables. For optimal utilization and maximum storage value, several applications should be within the operational repertoire of the storage unit. Other applications, including arbitrage, grid investment deferral, and load following, are additionally discussed. This thesis proposes a study and analysis of the Conti-Varlet approach or stretched-thread method (STM), a powerful graphical-based technique used to partial flow regularization for hydropower plants to provide auxiliary service regularization considering a battery energy storage system (BESS). The proposal is to keep the power more stable and constant as possible, mitigating the PV intermittence. A one-year analysis is performed for each BESS size, ranging from 10% to 90%. A cost for each scenario and an optimal BESS is presented to reduce the disutility. The changing of the consumption costs is defined as disutility.

In this work was developed a didactic and technical equipment for experimental study in a
reduced model to better understand the phenomena involved in the rupture of earth dams. The
structures were represented within a glass channel allowing visualization of the dam section,
filling of the reservoir and collection of deformation data before collapse of the structure. From
the laboratory tests to characterization of the soil used and the construction of the models, it
was verified that the experiment was an excellent analysis tool, since it was possible to
demonstrate the relation between time and the tendencies of the deformations and
displacements that precede a rupture and yet indicate the most critical areas at each moment,
favoring the suggestion of places where there should be greater attention regarding inspections
and installation of monitoring instrumentation. From the definition of these critical points, a
system was developed that, integrating hardware and software, is capable of identifying and
informing those responsible, in real time, of any undesired behavioral variation. The system
operates using sensors that perform distance analysis of the monitored structure and, through
an auxiliary processor, constantly transmits the collected data - connected to the network and
stored in the "cloud" - to a main processor. This processor receives the data and compares it
with previous data, making interpretations and conclusions regarding the stability of the dam
and issues alerts and reports in the form of spreadsheets and graphs that show in detail the
monitoring carried out in the periods selected by the user.

The integration of Photovoltaic and Battery Energy System (PV-BESS) has absorbed a lot of attentions in recent years within the renewable energy communities. The solar industry has shown significant interests in combining storage with solar installations as grid integration benefits have increased and at the same time the cost of storage system has decreased. Driven by best returns, variability of resources, solar module degradation and the best usage of inverters and medium voltage systems and step-up substation, the power conversion units, set of inverters and low voltage to medium voltage transformers, are usually rated for AC power values lower than those installed on their DC side for utility scale solar plants. This dissertation demonstrates that by boosting the DC/AC ratio of the PV plant, it would be feasible to improve the controllability of the solar generation and the project economics with integration of proper BESS size in the system. Data analysis on DC/AC ratio for PV plant with DC-Side BESS integration will be provided to demonstrate the typical price break down with the cost-benefit analyses based on financial evaluation metrics, for the economic assessment of PV plants subject to strong variation when applied to BESS assessment. Another advantage of the proposed system is to increase the amount of energy available in the hybrid plant, only by boosting its DC/AC ratio, keeping the whole AC system (i.e. cables, main power transformers, transmission lines) essentially the same. That solely might present a good advantage over the typical BESS applications which essentially only arbitrates AC energy already available in the system. In addition, the economic benefits that can be realized from a BESS depend on the application, the size of the PV system, the sophistication of the system’s control equipment, the customer’s rate structure and the operating costs. This work covers the literature review necessary to stablish the basis of the reasoning for further development of a methodology to determine the energy flow between the solar modules and the battery system, as well as the analysis of the financial indicator that serve to gauge the feasibility of an investment.

The high energy consumption in cases where there is a lack of power supply implies the need to invest in projects related to energetic efficiency. Once lighting highly influence the power demand of buildings and facilities, replacing traditional light bulbs with more efficient lighting  technology allows a significant decrease in the energy demand. Institutions such as university campus, which demand a large amount of electric power to supply light bulbs, have become targets of improvements of energetic efficiency projects. In this context, this work aims to analyze the purpose of replacing the current lighting system of a university in Itajubá, Minas Gerais state, with more modern systems in order to make improvements in its energy usage. To accomplish the aims of the research, energy performance indicators, IDE, is employed and allows researchers to promote actions on energetic efficiency based on the energy management system, SGE, from NBR 500001. The assessment of the economic feasibility of the work is performed through the main financial tools found in the literature (NPV, IRR, and Playback).

The results obtained show that all of the units studied present not only feasibl e economic return but also technical improvements as savings in energy is achieved and roughly equal to 28.612,06 kWh/year. In order to measure, verify, and evaluate the energy performance of the university, it was considered IDEs calculated for the current lighting system such as LBE. Those IDEs are compared to those calculated for the proposed system. With the results obtained from the case study, it was possible to identify energy-inefficient areas and propose improvements of IDEs in all units studied. IDEs presented a significant decrease in the proposed lighting system in comparison with the current one. The user indicator (Iu) resulted in 26.32 kWh / year / User with the proposed lighting system, and the area indicator (Ia) 5.98 kWh / year / Area.
These numbers show some improvements in the energy usage performance of the university as well as a lighting system more efficient.

The south of Minas Gerais offers a great potential for electric power generation from solar source. Given that renewable technologies also generate impacts throughout their useful life, it is crucial to analyze and compare the different energy generation technologies to determine which one has a better environmental profile throughout its life cycle. Considering these aspects, the present thesis proposes to evaluate and compare the environmental impacts and economic viability of four generation plants of renewable electricity, located in the city of Poços de Caldas, MG, using solar energy as energy source and employing the Life Cycle Assessment (LCA) methodology. The technologies analyzed in this study are: plant of photovoltaic panels with monocrystalline cells, plant of photovoltaic panels with polycrystalline cells, solar thermal concentration plant with parabolic troughs and solar thermal concentration plant with parabolic dish coupled to a Stirling engine. SIMAPRO 8.0.3.14 software was used to analyze the inventories. Ecoindicator RECIPE midpoint was used to evaluate the environmental impacts and RETScreen Expert software was used to determine the economic viability of each plant. Results showed that, for the functional unit of 1MWh of electric energy production and within the conditions addressed in this study, the parabolic dish solar concentration plant presented a good environmental and economic profile for the installation in the city of Poços de Caldas, MG. However, this technology still does not have commercial status for large scale installations, being overcome by polycrystalline photovoltaic technology, that presented the best environmental and economic profile, being the best installation option in this study, followed by monocrystalline photovoltaic technology and, finally, the technology of solar parabolic trough concentration, that presented higher emissions in the analyzed environmental categories.

An assessment of the dynamics of land cover and land use in and around a protected area (PA) located in the Serra da Mantiqueira Environmental Preservation Area (APASM) and Itatiaia National Park (PNI) in the Southeast of Brazil. In two contiguous watersheds, with an area of 24,757.65 hectares (ha), we seek proposals that lead to the recovery and maintenance of forests pressured by anthropic actions that have as induction vehicle the roads built around the AP. This PA is inserted in the Mata Atlântica (MA) biome, which is of great importance in the provision of water resources and the maintenance of biodiversity, since it is located among the largest and most populous urban centers in Brazil. The results obtained by Remote Sensing (RS) data, through multitemporal analysis, show that pasture areas grew 43% between 1985 and 2005 and forest areas declined 20% during that same period. Between 2005 and 2017, the pasture area declined by 22% and the forest area expanded by 26%. Urban sprawl grew steadily by almost 120% between 1985 and 2017. Between 2011 and 2017, by hand-screen demarcation using the Google Earth app, 855 scattered homes were found outside urban sprawl where park roads (PR) have been and are being opened. These unpaved roads are mainly concentrated near the paved road in 2011 and within and near the limits of the NIBP. In Geographic Information System (GIS) environment and employing multicriteria analysis with weighted sum to the environmental attributes of roads and urban spots, we also found that 85% of the study area is under high or very high pressure, which it may compromise the maintenance of biodiversity and water resources in the region due to the population increase induced by the back roads and its asphalting, which goes towards the limits of the NIBP. The results obtained may guide the implementation of more specific and effective legal tools, as well as guide the planning action of the local, municipal, state and federal actors involved in the region.

Anaerobic digestion is a complex process that depends on varying distances such as average pH, temperature, system agitation, toxicity, substrate type, maximum volumes and valves, organic loading rates and also carbon / nitrogen ratio (C / N). . The latter, in turn, was the central point in the development of the work. This ratio affects how bacteria in different stages of digestion and, depending on the unbalanced concentration of carbon and nitrogen, can affect inhibited energy metabolism in biogas production. Thus, in this licensed work, if you are going to study the coding study of a project with two co-substrates (corn silage and elephant grass) and an additive (charcoal), use the method of obtaining and increasing biogas production. Four possible scenarios are calculated, based on the substrates, co-substrates and additives indicated above, considering the production and sale of electricity through the energy compensation system. From an environmental perspective of Life Cycle Analysis or the result presented in Scenario II, the result of the best results for Global Warming Potential, Acidification, Eutrophication, Human Toxicity and Photochemical Oxidation was presented. Scenario III, in turn, shows the best result in the Ozone Layer depletion impact category and Scenario IV for Abiotic Depletion (Fossil Fuels). From the economic analysis performed, it was found or increased the biogas production and also the economic viability of the project with codigestion, and the scenario II (swine manure and elephant grass silage) was the one that presented higher profitability compared to Net Present Value and Scenario I (Supported Views) Show higher IRR for assumed propositions. Scenario shows an IRR of 21.69% and return on return on invested capital (TRC) of 6.2 years, while Scenario II shows an IRR of 21.14% and TRC of 6.5 years. Scenario III (swine manure and corn silage) and scenario IV (swine manure and charcoal) did not find economic viability. Finally, the Sensitivity Analysis performed in relation to economic viability is calculated on the analyzed parameters, but it has greater sensitivity regarding the variation of the price of electricity.

This research is a zero-dimensional thermodynamic study of spark ignition engines with the objective of evaluating the performance of the engines through the general performance parameters, such as power, torque and specific consumption of fuel, results of the thermal calculation performed in Matlab's Simulink software using different types of fuels. The thermal calculation is based on the first law of thermodynamics and the lifting of the external speed characteristic curve collaborates for the evaluation of the behavior and the development of engines with high performance, low emission levels of pollutants and fuel consumption. Wiebe's law is implemented to simulate the fraction of burnt mass and consequently the heat rate released by combustion. The results generated are: represented in external characteristics of velocity curves; first compares how the different fuels influence engine performance. Then is compared the results obtained through the implementation of Wiebe's law with the results before its application. Soon after compares the performance of ethanol and gasoline blends varying the compression ratio parameter within the usual ranges for each of the type of fuel in search of a more efficient engine with higher percentage of ethanol. Finally, the calculations are validated by comparing the results of this study with those found in the literature. The methodology of the thermal calculation evaluated has the same tendency found in the literature, however, in numerical values, the maximum pressure of the cycle, the power and the torque are overestimated and the specific consumption underestimated. This is because the hypothesis of instantaneous combustion at constant volume is the main cause of the high values of maximum pressure and effective mean pressure. Another factor that may be relevant to the imprecision of thermal calculation are the various parameters adopted within a range of empirical values.This can be resolved in a future model by creating an experimental test database to understand the performance of these parameters.

In recent years, Payments for Ecosystem Services (PES) have emerged as a form of financing for the conservation of natural resources, compensating landowners that generate positive environmental externalities. For the PES design process, defining priority areas aiming at the environmental recovery and preservation is essential for the efficient allocation of limited financial resources. In this sense, the present work aims to spatially identify priority areas for the implementation of PES schemes, with emphasis on the conservation of water resources, using as case study the Feijão River watershed, São Carlos-SP. For such, with help of geographic information systems (GIS), a multicriteria evaluation was applied for mapping priority areas for forest restoration based on relevant criteria related to landscape aspects for the provision of hydrological services by vegetation. The resulted information plan was then cross-referenced with estimated opportunity costs for compensating landowners in order to identify higher priorities associated with low cost sites. The results show that 25.6% of the eligible areas for forest conversion have very high priority to restoration, and are located mainly along the main river watercourse, with predominance of pasture and sugarcane uses, the main driven forces of erosion processes in the watershed. Among the agricultural activities, livestock presented the lowest opportunity cost, corresponding to a reference value of R$ 223.53/ha/year in PES. 99 rural properties with areas of interest for PES schemes were identified (898.27 ha, 3.7% of the total watershed area), totaling a payment amount of R$ 200.789,80 per year to producers. The PES project proved to be economically viable when the result is compared to the average willingness to pay (WTP) of the population of São Carlos for the protection of water resources. Finally, the use of multicriteria evaluation combined with economic analysis of land use presented as a flexible and straightforward methodological approach, whose results can support further watershed planning and management.
Keywords: