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This work analyzes the use of artificial neural networks in the short-term streamflow forecasting for large interconnected hydropower systems. The state-of-the-art optimization algorithms, activation functions, and weight initialization techniques are investigated together with classic methods. We present an algorithm to define the neural network inputs in large hydrosystems and apply it to create models for 55 major hydro plants located in the Paraná Basin, which contribute to more than 30% of the total power generated in Brazil. The paper also compares the performance of the neural networks with the hydrological models that are currently used by the independent system operator to define the dispatch of the electric power generators. Our results show that, overall, the neural network models provide more accurate forecasts than the hydrological models used by the Brazilian System Operator. Finally, the paper discusses the contributions of historical rainfall information in the forecasting of streamflow while using neural network models. [ABSTRACT FROM AUTHOR]

This paper depicts an accident that happened in 2010 in a Brazilian chemical plant. A combination of different events, installations, and commissioning errors coupled with equipment failures involving the primary substation resulted in catastrophic failure. A single-phase failure of a 138-kV disconnect switch, during closing, initiated events and phenomena that resulted in a complete plant shutdown. This paper will walk the reader through the events, forensics analysis, and power system analysis that allowed the authors to identify what happened, how it happened, and what to do to prevent it from happening again. This paper will show how the anatomy of the problem, involving equipment failure, single-phase arcing, switching transients, overvoltage, capacitive coupling, transferred surge voltages, ungrounded system, transient overvoltage due to an arcing ground fault on an ungrounded system, insulation coordination, flashover, and lack of adequate surge protection, all of which resulted in a catastrophic failure of an arc resistant switchgear and a potentially serious arc flash incident. The research followed some steps that will be commented on here as well as the lessons learned. [ABSTRACT FROM AUTHOR]

In the rural regions of southern Brazil, electricity is largely directed to irrigation activities on rice crops at restricted periods of the year. Typically, customers in these regions are called "irrigators", and have some characteristics different from loads in urban centers, such as high demand levels and sharp load variations. These characteristics can result in problems of excessive loading on distribution grids at certain times of the day, generating concerns for the power utilities in relation to the security of the electrical system, energy supply to customers, and the integrity of electrical equipment. An alternative to avoid or mitigate these possible problems may be the application of a demand management model to irrigator customers. In this context, a load shifting strategy can be inserted to reduce demand in more critical periods and move it to intervals with lower load on the power grid. In this context, this article presents a demand-side management methodology in distribution systems located in rural areas, employing the load shifting strategy for irrigator customers. The methodology proposed in this paper is not an entirely novel approach, but one specifically developed for the context of irrigator customers, a subject little studied in the literature. The load management model proposed by this study is segmented into three hierarchical levels. The first level is the identification of the electrical characteristics of the distribution systems, the second level is the power flow analysis of the distribution networks, and the third and last level consists in the application of load shifting to the irrigator customers of these electrical systems. The load shifting strategy is modeled by a linear programming algorithm and is only applied to irrigator customers in situations of excessive loading on power grid. The case studies were conducted on three distribution systems of a power utility, with more than 150 irrigator customers. The DSM model based on the load shifting strategy reduced the maximum demand and daily load variations on the three rural feeders evaluated. The proposed changes in load patterns can ensure the continuity of electric power supply service in future even with the high concentration of load on distribution networks, benefiting customers and power utilities. [ABSTRACT FROM AUTHOR]

An electric power distribution utility is responsible for providing energy to consumers in a continuous and stable way. Failures in the electrical power system reduce the reliability indexes of the grid, directly harming its performance. For this reason, there is a need for failure prediction to reestablish power in the shortest possible time. Considering an evaluation of the number of failures over time, this paper proposes performing failure prediction during the first year of the pandemic in Brazil (2020) to verify the feasibility of using time series forecasting models for fault prediction. The long short-term memory (LSTM) model will be evaluated to obtain a forecast result that an electric power utility can use to organize maintenance teams. The wavelet transform has shown itself to be promising in improving the predictive ability of LSTM, making the wavelet LSTM model suitable for the study at hand. The assessments show that the proposed approach has better results regarding the error in prediction and has robustness when statistical analysis is performed. [ABSTRACT FROM AUTHOR]

This paper proposes a hybrid approach based on ID3 decision tree and expert systems to the load forecasting. The proposed model considers the typification of weekdays and uses the influence of climate information to estimate the load. The proposed methodology was tested on real data of electrical load measured in southeast of Brazil. The results show that the proposed model was promising with competitive results in the load forecasting area. [ABSTRACT FROM AUTHOR]

Did Latin American privatisation policies fail because of flawed implementation of fundamentally sound policies or because privatisation policies were themselves seriously flawed? Using the Brazilian electric power reforms as a narrative tool, this paper examines the causal chain assumed by large-scale privatisation policies that were implemented as part of structural reform and adjustment programmes. The paper concludes that many privatisation policies and the economic stabilisation programmes within which they were embedded were not mutually reinforcing in the way that policymakers had expected, and that in their application much of what privatisation theories had claimed was lost in translation. [ABSTRACT FROM AUTHOR]

Copyright of Revista Jurídica (0103-3506) is the property of Revista Juridica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The Brazilian petroleum and chemical industry had basically used medium-voltage (MV) power assemblies based on ANSI/NEMA for many years. However, in the last three decades, due to the Brazilian Standard Association orientation, the users and manufacturers have been changing their philosophies to the IEC culture. As there has been an everyday increase in the opportunity and also in the need of MV electrical power distribution in petrochemical facilities, there is the chance of adopting an MV switchgear or controlgear design based on ANSI or IEC standards, according to each plant specifications. Although the use and design of MV assemblies are based on the electric power system needs and characteristics, they are also a result of the current scenario and experience of a specific petrochemical facility. Since both ANSI and IEC universes have strong experience, knowledge, and huge safety concerns in electrical equipment design and application, the final choice is an interesting decision. It is important to keep in mind that the use of MV assemblies has to face technical and safety key issues as they are connected to an industrial power system, and both ANSI and IEC deal with such requirements very carefully: each one in its own way. This paper deals with impacting topics related to MV switchgear and controlgear such as the following: 1) ANSI and IEC requirements; 2) rated values and characteristics; 3) ancillary and power equipment application; 4) safety; and 5) ergonomics. [ABSTRACT FROM AUTHOR]

From the end of 2013 to the end of 2015, Brazil faced serious challenges to supply its demand for electricity due to a prolonged drought in the Southeast and Northeast regions with the consequent loss of hydroelectric generation. This paper presents an historical analysis of major world energy crises from 1988 to 2015 and in Brazil from 1924 to 2015. Analysing the natural river flow of key Brazilian dams from 1931 until 2017, this paper suggests that hydropower generation in Brazil has a 10–15 years cyclical pattern of hydropower generation. The periods of drought in this cyclical pattern usually coincides with energy crises due to the reduction in hydropower generation. It was found that the drought in 2015 had an impact of 110 TWh in hydropower generation, from which 25 TWh are due to head loss and 70 TWh are from lack of stored hydropower in July of 2014. In addition, 48 TWh were not generated due to delays in the construction of new power plants. Other causes of the Brazilian energy crisis of 2015 are presented and the overall electricity generation impact of these causes are compared. In addition, this paper presents the impacts on the energy, water and food supply sectors in Brazil, and the strategies employed to reduce the impact of the crises. With the intention of preventing future energy crises, the paper then shows the potential alternatives to improve electricity supply security in Brazil, particularly in terms of diversifying and widening the share of renewable sources and increasing the energy storage potential of the country. [ABSTRACT FROM AUTHOR]

Electricity generation in Brazil heavily depends on hydroelectric power, making it vulnerable to fluctuations due to its reliance on weather patterns. Accurately forecasting water inflow into hydroelectric plants is vital for the National Electric System Operator to make decisions regarding the monthly scheduling and operation of the power system. In this paper, an evaluation of predicted flows for a 14-day horizon are evaluated for the Tucuruíhydroelectric plant, located in the Tocantins river in the North of Brazil. The temporal fusion transformer (TFT), long short-term memory (LSTM), and temporal convolutional networks (TCN) are compared. The findings demonstrate that the TFT is a more suitable alternative than LSTM and TCN models for predicting inflows for the next 14 days. The TFT model is hypertuned by Optuna to achieve an optimized structure (h-TFT). The h-TFT had a mean absolute percentage error of 13.1 and a Nash–Sutcliffe of 0.96, outperforming its initial version and even the bidirectional LSTM model in benchmarking. Based on the error results, h-TFT showed promise for flow forecasting and provides insights into decision-making processes in the Brazilian electricity sector. • Hypertuning the TFT improves its performance in median-term forecasting. • The h-TFT outperforms LSTM, and TCN models for time series forecasting. • Deep learning applied for scheduling operation of the electrical power system. • Energy planning based on the inflow forecasting of hydroelectric power plants. [ABSTRACT FROM AUTHOR]

Over the past decade, electric power systems have been restructured based on different models to introduce competition among market participants. Transmission open access for suppliers and customers is one of the most prevailing unbundling services. Usually, a connection tariff is established based on different market factors, including the actual usage of the transmission network. In Brazil, most vertically integrated companies owned by the federal and state governments were unbundled, and new transmission companies are being created. These companies make their assets available to the independent system operator, designated as Operador Nacional do Sistema Elétrico (ONS). One of the main objectives of ONS is to manage transmission services, over a certain voltage level, to ensure nondiscriminatory access to the grid. All transmission users, including regional distribution companies, pay wheeling transmission charges at each delivery or connection point with the major Brazilian network administrated by ONS. This paper presents a methodology for determining the optimal amount of transmission system usage (ATSU) that must be contracted by a regional distribution company, at each connection point. In the proposed approach, the maximum flow at each connection is represented as a random variable in order to obtain the distribution probability of the transmission charges as a function of the ATSU parameter. Besides providing the optimal amounts to be contracted, the proposed probabilistic methodology allows quantifying the risks of violation of each contract and estimating possible penalties. All methodology development steps are described and illustrated through numerical examples. An application to a typical Brazilian regional distribution company is also discussed. [ABSTRACT FROM AUTHOR]

In this paper, the optimal active power dispatch is formulated as a network flow optimization model and solved by interior point methods. The primal-dual and predictor-corrector versions of such interior point methods are developed and the resulting matrix structure is explored. This structure leads to very fast iterations since it is possible to reduce the linear system either to the number of buses or to the number of independent loops. Either matrix is invariant and can be factored offline. As a consequence of such matrix manipulations, a linear system which changes at each iteration has to be solved; its size, however, reduces to the number of generating units. These methods were applied to IEEE and Brazilian power systems and the numerical results were obtained using a C implementation. Both interior point methods proved to be robust and achieved fast convergence in all instances tested. [ABSTRACT FROM AUTHOR]

The Brazilian Electricity Regulatory Agency (ANEEL) presented a proposal to revise the tariff structure of distribution companies in Brazil. One of the main approved suggestions was to establish a mechanism called Tariff Flags, which aims to foster a Demand Response Program in Brazil via an increase in the energy tariff. In this work, the proposed mechanism is reviewed in detail and the expected results of its application are simulated and analyzed under different perspectives. This paper shows that the system operation directly impacts the Demand Response Program, since the spot prices will define which Tariff Flag should be triggered. In order to encompass and assess the main consequences of its application, this paper presents the expected effects on energy spot prices, system operating costs, probability of triggering each flag, investment recovery for utilities and finally, the impact for the final consumers. The case studies presented in this paper were developed using real information about the Brazilian electrical system for each economic sector and the price-demand elasticity is discussed using the literature for this application. Finally, some conclusions and guidelines are provided to improve the application of the mechanism. [ABSTRACT FROM AUTHOR]

This paper evaluates the economic (electric power rates and utilities revenues), environmental (GHG emissions), social (job creation) and political (tax collection) impacts of a wider diffusion of photovoltaic distributed generation (PVDG) and energy efficiency (EE) measures on the markets of electric power distribution utilities in Brazil. The impacts are calculated for three substantially different power distribution utilities, which are representative of the types of utilities found in the country. Key indicators were selected to reflect the main interests of the following stakeholders: power distribution utilities, the government (Federal, State and Municipal) and low-voltage consumers. The results show that the most important issues that should be addressed concerning a large diffusion of EE measures are tax collection and tariff rises. The simulations show that tariff rises can be hampered by EE actions targeted to specific locations and specific actions. The most important impact of PVDG diffusion is on tariff rises, considering the current regulatory framework in the country. On the other hand, the net jobs creations of EE measures and, particularly, PVDG are significant and the cost of job creation in relation to fiscal waiver by investment on PVDG is cost-effective. The GHG emissions avoided by the higher levels of PVDG and EE in 2040, simulated in this study, showed to be significant for both EE measures and PVDG. • Description of Key indicators selected to reflect the main interests of utilities, the government and consumers. • Quantify impacts on indicators. • Analysis and discussion of impacts on indicators. [ABSTRACT FROM AUTHOR]

The micro- and mini-distributed generation (MMDG) has significantly increased after the normative resolution No. 482/2012 in Brazil; the installed capacity surpassed 7 GW in 2021. In the international context, a similar event was observed, whose process generated a cross-subsidy for other consumers, in addition to other problems that affect the economic balance of concessionaires. To mitigate this issue, the National Electric Energy Agency (ANEEL) is in the process of revising current rules. Thus, this study estimates the weight of this decision, through a methodology adapted from international assessment models, based on information from the Brazilian regulatory system. In order to achieve it, this paper presents metrics to define the potential market MMDG, based on the consumption patterns of consumers. Then, through time series analysis, the MMDG demand curve is estimated under two scenarios up to 2030. Finally, the economic impact on tariff adjustments and revisions, and their effect on the electric power concessionaires are evaluated. In the distribution companies of the Enel Group alone, economic losses are estimated at USD 1.2 billion by 2030; 53% of this will be passed on to consumers' tariffs. Thus, based on international experiences, it can be concluded that the best model is the adequate grid remuneration. [ABSTRACT FROM AUTHOR]

The firm energy of generation plants is a critical component in some electricity markets. It is usually calculated by the regulator and sets a cap to the amount a plant can trade in capacity markets (or auctions), in order to avoid free-riding behaviors. Firm energy is a systemic property and, in case of hydro plants, a synergy is observed whenever a cooperative operation occurs, i.e., the firm energy of a system is greater than the sum of the individual plants. This immediately raises the question of how to divide the system's firm energy among the individual hydro plants. The objective of this work is to investigate the application of different allocation methods of firm energy rights among hydro plants using a game-theoretic framework. It is shown that there is not an optimal and unique approach to make this allocation. The paper investigates the advantages and disadvantages of different methods, such as marginal allocation, average production during the critical period, incremental allocation, finally recommending the Aumann-Shapley as the allocation method. This method is tested for the Brazilian power system, which has around 100 hydro plants. The results obtained are compared with the current allocation adopted by the electricity regulatory agency of Brazil. [ABSTRACT FROM AUTHOR]

In this paper the design of power system stabilizers for small-signal stability using phasor measurements is considered. An approach based on optimal control with structural constraints is proposed to design a two-level control structure. Time delays are included in the design. The method is combined with order reduction to ensure faster convergence of the design algorithm and to facilitate the choice of the weighting matrices for damping inter-area modes. The control scheme is discussed and modal analysis and time-domain simulations of two Brazilian equivalent systems are performed to assess the control performance. The robustness to loss of communication links, topological changes, and variations of time delay is evaluated. [ABSTRACT FROM AUTHOR]

Two methods have been largely studied and used in power systems reliability assessment: contingency enumeration and nonsequential Monte Carlo simulation. Both have their advantages and drawbacks. Contingency enumeration is conceptually simple and usually requires low computational effort. Conversely, Monte Carlo simulation is computationally harder, but much more versatile to model random aspects. This paper depicts some important practical aspects regarding the application of both methods, emphasizing how they can be used in a complementary way. The Brazilian interconnected electrical system is used to illustrate the risk assessment of an actual large scale power system, utilizing both techniques. [ABSTRACT FROM AUTHOR]

Abstract: During the past decade, the Brazilian electric power sector went through similar institutional changes taken place in both developing and developed countries. The main goals for such changes were to inject competition into the generation and supply links of the sector''s production chain and to reduce public debt via privatization of state-owned utilities that dominated the pre-reform sector. This paper discusses why these changes took place in Brazil and explains why the results of the reform model implemented by the previous federal administration were unsatisfactory. The current federal administration has substantially altered the prior model, aiming to remedy insufficient private investment in new power stations that caused a serious power shortage in 2001. The paper addresses the main characteristics of the new model, which implements (a) public biddings of new power plants for all distribution utilities in the country, and (b) forward planning of optimal commissioning times and capacity of new plants. The paper ends with a discussion of the potential benefits and drawbacks of the new scheme and the role of the regulator in the early stage of the ongoing transition in the Brazilian electrical power industry. [Copyright &y& Elsevier]

In Northeast Brazil, the use of biomass for energy generation is settled on traditional productive arrangements, such as a sugarcane production system in the humid Atlantic coastal area and firewood extraction from native tropical dry forests in the west. In parallel, substantial amounts of other biomass sources, such as residues from agricultural or urban processes, are still little used or wholly wasted, fudging the opportunity to generate new value chains based on these biomass sources. We hypothesize that using these non-traditional biomass sources to produce biofuels would significantly increase the regional bioenergy supply. In this context, this article discusses the potential for the production and use of biofuels and bioenergy in Northeast Brazil and its effects on regional development, which may be useful for both private actors and policymakers in the energy sector. The use of biomass sources for energy in the region is significant, reaching approximately 8.8 million tons of oil equivalent (toe) per year, emphasizing the already consolidated production of sugarcane and its derivatives. The use of all biomass resources in the Northeast region could supply around 4% of the Brazilian national electrical energy demand, with an environmental footprint of 0.055 tCO2eq per toe, which would contribute to reducing emissions from the Brazilian energy matrix generation. Regarding the spatial distribution of biomass sources, sugarcane prevails on the coast, firewood and livestock manure in the dryland area towards the west, and municipal solid waste is distributed throughout the region within urban areas. Different from what we expected, the potential energy recovery from municipal waste and animal manure would increase by only 17% the current bioenergy supply. In the future, since the majority of the region presents a semi-arid climate with limited rainfall, to increase the use of biomass as an energy source, there is a need to increase the supply of biomass sources with high efficiency in water use and good yields in drylands. For this, the cultivation and use of cacti and agave, for example, could contribute to making biorefineries viable in the region. Above all, public policies for harnessing bioenergy in NE Brazil must seek opportunities associated with the carbon/decarbonization economy, with studies being needed to assess the technical, economic, social, and environmental viability of future productive arrangements. [ABSTRACT FROM AUTHOR]

Voltage Sags are the most disturbing power quality deviation to the sensitive industrial loads causing production losses and other impacts to the equipment end users and distributors of electricity. A new methodology for estimation of voltage sag patterns and clustering of distribution substations with similar features for voltage sags is the main contribution of this paper. The focus is on the regulation of this phenomenon in Brazil. Network modeling and faults simulations in transmission and distribution levels were performed in a Brazilian actual distribution system with 17 substations in order to get information regarding the number of voltage sags caused in the substations bus bars. Principal Component Analysis was applied on a significant number of variables containing relevant information of power quality and design features of the substations and storing the major Principal Components Scores. Furthermore, Clusters of substations with similar characteristics to voltage sags were formed and assigned a specific Membership to each substation. The expected annual number of voltage sags is the solution. A 95% Confidence Interval for the total number of voltage sags was estimated, leading to the classification of the main variables related to the voltage sags by clusters formed. Clusters of Substations with similarities for regulatory purpose of voltage sags were the principal results, followed by classification of the main variables associated with voltage sags by the clusters formed. A critical analysis of the results and a comparison among different Clustering Methods reaffirmed the assertiveness of the proposed methodology for the management of power quality associated with voltage sags, by the Regulator and the distribution utilities in Brazil. [ABSTRACT FROM AUTHOR]

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Copyright of Revista Brasileira de Políticas Públicas is the property of Revista Brasileira de Politicas Publicas and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract: In Brazilian low-income households, water-heating requirements are typically met by electrical showerheads. On average, 73.1% of all residential units in the country are equipped with these resistance-heating devices, with nominal powers ranging from 3 to 8kW. This situation imposes a considerable burden on the electricity utility companies, since electrical showerheads typically represent the highest load but the lowest utilization (load factor) in a residential consumer unit. Furthermore, typical utilization times coincide with, and contribute to, the electrical power demand peaks in Brazil, rendering these low-cost, high-power electrical devices a high-cost consumer for the electrical system to cater for. For low-income residential consumers, electricity tariffs are subsidized, and utilities must therefore make a considerable investment in infrastructure for a limited return. In this paper we analyze the impacts of solar water heating in low-income households on the distribution utility active, reactive and apparent power demands. We have monitored a statistically representative group of low-income residences equipped with a compact domestic solar water heater in Florianopolis – Brazil for 1year. We show that in comparison with identical residential units using electrical showerheads, with the adoption of solar water heating the reductions in the active, reactive and apparent power demands on the distribution utility were 49%, 29% and 49% respectively. [Copyright &y& Elsevier]

Abstract: This paper presents an analysis of the feasibility of implementing biomass power plants, through thermoelectric power generation, and adding such plants to the electric system of the local electric utility by means of independent power production. Economic, regulatory, and market issues are also addressed. The biomass being considered is produced by the lumber sector, since that is one of the industrial sectors generating the largest amount of residues in a concentrated manner in the region under study, and also considering the fact that the disposal of such residues is currently difficult for the lumber companies. The locations with the largest production of residues, as well as the size of potential plants, are identified, the generation costs of the plants calculated, and the feasibility for implementing the plants is evaluated considering the market and the regulation of the Brazilian electric power sector. [ABSTRACT FROM AUTHOR]

Abstract: This paper focuses on supplying electrical power for remote communities of the Brazilian Amazon using regional biomass, specifically palm oil biomass, as a primary energy source. The use of Straight Vegetable Oil (SVO) as fuel, is indicated for isolated communities, where the hydro plants or the installation of transmissions line are impracticable. The use of vegetable oils produced in the communities, is a solution when an adequate infrastructure to extracting the oil is available. Brazil is able to use an enormous diversity of vegetable oils, due to a great variety of plants, and the favorable climatic conditions. Technical, economic, environmental and social aspects are analyzed in order to provide a basis for electrical power supply viability in these communities. A case study is presented focused on a typical Brazilian Amazon community located in the State of Pará in order to demonstrate the applicability of the proposed viability strategy. [Copyright &y& Elsevier]

Abstract: The Brazilian North and Northeast regions have possibilities on harnessing tidal power, where the greatest tidal amplitudes are to be found. In the 1970s, a barrage constructed in the Bacanga estuary, a civil construction project for reducing the distance between the city of São Luís do Maranhão and the port of Itaqui, was planned to be the first Brazilian tidal power plant. The favorable conditions associated with the considerable tidal heights, which can be as much as 6.5m, made this an ideal place for building a pilot plant. Although, a scheme had been proposed to harness tidal energy in a conventional way with the use of the reservoir, the tidal plant in its original form was not implemented due economic and technical restrictions originated from the turbo generators chosen at that time. This paper presents an alternative concept for tidal power plant when the reservoir presents limitations caused by urban occupation, silting up and deterioration of the original structures. These limitations have been verified following the construction of the Bacanga barrage which led to an alternative proposal for the future installation of a pilot tidal power plant. The power generation possible to be harnessed was simulated through a model for each hour from the water head data, outflow, levels, areas and volumes of the reservoir and estuary. The development of the conceptual project, with the utilization of low-head turbines, a floating platform for the turbines and, particularly, taking into consideration those restrictions to be found at the present time, it can be concluded that Bacanga tidal power plant of is technically viable. [Copyright &y& Elsevier]

In Brazil, ninety percent of total electric power comes from renewable sources, where hydropower represents 2/3 of the national energy matrix. In 2012, the new Federal Forest Code eliminated environmental protection along drainage divides and reduced the mandatory width of riparian zones, allowing for land cover change in these environmentally sensitive areas. The conversion of forestlands to agriculture will subject hydroelectric reservoirs to a growing load of sediments, shortening their useful life. In this study of the Furnas hydropower plant and its contributing basin, in the upper reaches of the Rio Grande, a re-evaluation of factors that determine the distribution of finances accrued from hydroelectric generation is recommended. Under the current policy, royalties are paid by the Furnas facility to states and municipalities in direct relation to the area of land flooded by its reservoir, whereas contributing rainfall precipitating in municipalities upstream of the lake is not considered. Currently, the 31 municipalities with lands flooded by the reservoir receive an average of R$ 213,107 (US$ 67,226) annually, while the remaining 172 municipalities in the basin receive no water royalties. In the proposed approach to redistribute these funds, each of the 203 municipalities will receive compensation determined by their contributing catchment area, averaging R$32,543 (US$ 10,266) per year. By considering distribution of rainfall in order to equitably allocate hydroelectric royalties, a system for the payment of environmental services is conceived. Such a system intends to incent stakeholders to protect or replant native forests along drainage divides and riparian zones, in recognition of the value this vegetation has in the reduction of long term costs for hydroelectric facilities. [ABSTRACT FROM AUTHOR]

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In this article, the Brazilian Model for Public-Private Partnership (PPP) is described. It was conceived envisaging investments for the completion of new electric sustainable power plants. The objective is to present the main drivers in Brazilian regulatory system for private investors in what relates to risks configuration and investment decision-making, either Brazilian or foreign ones. We analyzed the investment in 5 Brazilian power plants that altogether constitute an electric power-generating complex in Juruena River, in the state of Mato Grosso, in Brazil. According to the results, we can conclude that the present legal framework is able to support investment in small hydroelectric and sustainable power plants, considering the existence of Engineering Procurement Contracts (EPC) for the completion phase and of Power Purchase Agreements (PPA) for the operational phase as well. [ABSTRACT FROM AUTHOR]

Copyright of Petroleum - Gas University of Ploiesti Bulletin, Law & Social Sciences Series is the property of Petroleum - Gas University of Ploiesti and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A macroscopic mini-model of Brazil’s electrical generating capacity (BRAZELECTRIX, Brazilian Electricity Ma trix) was developed using the Energy Systems Language and simulated with iconographic Extend® software to explore long-term (200 years) population carrying capacity. South American reserves of natural gas (NG) and Brazilian stream hydro-power potential were assumed as the main inputs to electric power production. Energy values (e.g., kWh, joules) for fuels, electricity and environment were transformed to solar emergy (i.e., solar equivalent joules) to simplify cross comparison with a single metric. BRAZELECTRIX was calibrated using a holistic method that used mean component life-times and conservation of material and energy for each individual unit. Validation of BRAZELECTRIX, based on historical data, gave a root mean square error of 8% for hydroelectricity and 28% for natural gas use. Investments in natural gas infrastructure (e.g., contracts, pipelines, processing plants and electric power plants) accelerated Brazil’s expansion of electrical generating capacity for a finite period, allowing the country to reach its renewable (hydro-power only) carrying capacity 100 years sooner than without (2040 vs. 2140). Brazil has a total of 560 zetta-solar equivalent joules per annum (1 Zseja = 1 ×1021 sej per year) of stream hydro-power potential; 170 Zseja is currently used for electricity generation. According to BRAZELECTRIX, eventually 390 Zseja will be tapped for hydroelectricity. The standard of living, as measured by annual per capita electrical solar emergy, had risen 680% from 166 tera-solar equivalent joules (Tseja) to 1130 Tseja during the 35 year period following 1965 and was predicted to increase another 75% to its maximum (1973 Tseja) in 2050. By comparison, an urbanizing state of the United States (North Carolina) had an annual per capita electrical solar emergy of 7815 Tseja in 1992, indicating that Brazil could reach a living standard, as measured by per capita electricity usage, equal to one-forth the level of United States. Macroscopic mini-models combined with emergy accounting evaluated long-term paths for Brazil’s electricity supply and related it to natural environment trade-offs to demonstrate how sustainable carrying capacity of a developing nation can be forecast. [ABSTRACT FROM AUTHOR]