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The use of Distributed Generation (DG) is essential to reach the Decarbonization, Decentralization and Digitization. However, DG can cause impacts on the electric power systems. Among the impacts, this work proposes to analyze the changes in the Power Factor (PF) caused by the use of photovoltaic DG. For the study, generation and consumption data are collected in a prosumer unit located in Criciúma, Santa Catarina, Brazil. Two days are used in the analysis, one with a generation higher than the load and another with a generation lower than the load. Current Brazilian legislation is considered in the analyses carried out along the paper. The results obtained indicate changes in the PF of the prosumer due to the use of photovoltaic DG. [ABSTRACT FROM AUTHOR]

This paper propounds a new metaheuristic optimization algorithm to obtain the optimum site and size of distributed generation (DG) in radial distribution system (RDS). This problem is concomitant with reducing the active power loss, the total voltage deviation and the voltage stability index of the RDS considering different types of load models (such as constant power (CP), industrial (IL), residential (RES) as well as commercial (COM)). To solve this weighting factor-based multi-objective DG allocation problem, a novel metaheuristic optimization algorithm, student psychology-based optimization (SPBO), is suggested in this article. A multi-criteria approach (such as the analytic hierarchy process) is employed to optimize the weighting factors involved. To the best of the authors' knowledge, this is the first time that this novel SPBO algorithm is being used for optimal siting and sizing of DGs in the RDS for different types of load models (like CP, IL, RES and COM) for IEEE 33-bus, IEEE 69-bus and practical Brazil 136-bus RDS. The simulation results attained by the proposed SPBO algorithm are compared with the results provided by recently surfaced Harris hawks optimization (HHO) algorithm and other state-of-the-art algorithms. The outcomes prove that the suggested SPBO algorithm is more efficient to solve the optimal multiple DG allocation problem with minimum real power loss, less computational time and prominent convergence rate. [ABSTRACT FROM AUTHOR]

Summary: Brazil has one of the richest river basins in the world and an energy matrix based mostly on hydroelectric power. Current national policy is increasingly promoting renewable sources like wind power and solar photovoltaic power. Technologies used in generation energy via hydro, wind, and solar sources can be employed in decentralized generation. This study describes a turbine for hydro energetic use in flow sites with heads up to 2.5 (m). A hydrodynamic study was performed using computational fluid dynamics (CFD) analysis to evaluate the performance of this turbine. For this, a three‐dimensional model of the turbine was considered, consisting of three computational domains, using periodicity to decrease the computational cost. The variation of the angular velocity and the volumetric flow were the boundary conditions. The turbulence model used was the shear stress transport. The draft tube geometry was modified according to the results of the CFD analysis. The efficiency and performance of the turbine improved from 79% to 80% as a result of this modification. A case study was conducted for a comparative financial analysis of the turbine proposed in this paper, with wind power and solar photovoltaic decentralized generation in Brazil. [ABSTRACT FROM AUTHOR]

This paper examines the remarkable growth of photovoltaic (PV) solar energy technology in Brazil, which stands out among the leading countries in photovoltaic installations. The recent implementation of Law 14300 on grid-connected PV systems has caused a stir in the Brazilian market, with investors anticipating installations to avoid reductions in benefits. This phenomenon, previously observed in Europe, instigates an understanding of the variables underlying the exponential growth of the Brazilian market. This study seeks to identify the predictors that explain the PV systems diffusion in Brazil, in two stages: a systematic review of the literature to map approaches and methods, followed by the construction of a database and the application of predictive models. The literature revealed 24 methods in six approaches, with 44 predictors. For Brazil, the database contains 90,129 instances, 22 predictors, and covers all 5570 municipalities. The results highlight the crucial importance of the electricity tariff as the main predictor, followed by irradiation and municipal Gross Domestic Product. Predictors such as the number of companies, minimum wage, HDI education, demographic density, and vehicle fleet prove to be relevant. In conclusion, the spatially explicit analysis highlights the complexity of the market, offering valuable implications for energy planners and stakeholders. [ABSTRACT FROM AUTHOR]

The 100-years-old model of centralized generation and one-way power flow is being disrupted by alternative energy technologies that enable customers to generate their own electricity. The massification of distributed generation (DG) started lately in Brazil, but it growth fast in capacity since then. The electric utilities have presented technical and economical challenges arising from the increased diffusion rate of DG. Due to lack of studies addressing performance metrics suitable for this scenario, this paper proposes a measurement system for determination of the overall performance index of electric utilities related to DG services. The methodology has been developed based on Delphi method and Balanced Scorecards to define 32 objectives. Analytic Hierarchy Process concepts was applied for weighing objectives perspectives and to derive an overall performance index. Overall performance indexes related to DG found from application of proposed model in all companies were lower then 50%. No one of the evaluated companies achieved a regular or satisfactory performance. This result confirmes that electric utilities companies are far from reaching expected satisfaction factors related to DG services. The introduced methodology can be used by the scientific community and policy-makers of any country to better inform to a new energy distribution and generation scenario. • A performance measurement system with multicriteria decision methods BSC-AHP. • A methodology that is easily replicable by researchers from other countries. • In Brazil, no electric utility is at an advanced organizational level index of DG. • Organizational management of the distributed generation in electric utilities. [ABSTRACT FROM AUTHOR]

Distributed generation (DG) plays a strategic role in transitioning from a fossil to a renewable energy matrix, encouraging the reduction of energy poverty and access to green energy in traditional communities. This paper proposes a statistical model based on structural equations to analyze the influence of DG on Well-Being (CWB), and to estimate the causal relationships between the latent variables: economic (ECO), environmental (ENV), social (SOC), distributed generation system (DGS) and well-being (CWB) in a rural area in Brazil. The research is carried out in a Quilombola Community located in the south of Brazil. In the data collection process, a questionnaire was used in a Likert scale format, applied in loco to the residents of the Quilombola community. This database was imported into the SmartPLS software for analysis using a partial least squares approach. Structural equation-based modelling (SEM) results confirmed 66% of the hypotheses. The latent variables SOC and DGS directly and positively affected CWB with (β = 0.573) and (β = 0.433), respectively. The Economic variable with (β = 0.396) had a direct and positive effect on the DGS variable, and the DGS variable with (β = 0.404) had an immediate and positive impact on the CWB. The variables observed with the highest participation in the latent variables were: belonging (62%), social capital (31%), greenhouse gases (56%) and incentive policies (45%). The proposed model demonstrates that socioeconomic changes, carried out from specific public policies around the installation of DG, should contribute to the well-being of traditional communities and the reduction of energy poverty. • An analysis of the well-being development of a rural community was done. • For data collection process was used a Likert scale. • Only the social dimension had a direct effect on the well-being of the community. • The designed model demonstrated that the variables are susceptible to changes, influencing on public policies. • DG promotes well-being beyond technical issues and should encourage its installation in rural communities. [ABSTRACT FROM AUTHOR]

• Proposed method to evaluate PV + BESS economic landscape for brazilian dwellings. • Positive impact of adopting a BESS in the PU from the energy perspective. • BESS costs impact economic viability and need government incentive. • Method can be adapted to other scenarios. This paper proposes a methodology to assess the energy and economic impact of adopting small-scale residential photovoltaic (PV) systems paired with lithium-ion battery energy storage (BESS) systems in single-family homes, under the current energy feed-in legislation. The suggested methodology was applied to a case study of a prosumer unit (PU) in Brazil. Data from energy bills, measured PV generation, BESS behaviour, and energy consumption were analysed to compare different viewpoints and estimate key economic indicators. As a result, the PV + BESS combination increases residential users' energy self-consumption and self-sufficiency, resulting in respective increases of 15 % and 2 %. Under the conventional tariff, adopting the PV + BESS system led to an average 29 % reduction in electricity costs compared to scenarios without PV + BESS. Furthermore, by transitioning to the white tariff mode in conjunction with PV + BESS, the PU achieved a 49 % reduction. This result emphasizes the advantages of time-of-use adoption for PV + BESS consumers. A greater discrepancy between tariff periods enhances the feasibility of storing off-peak energy for use during peak periods. Currently, BESS implementation costs impede competitiveness, with attractive LCOS metrics achieved only at costs below $600.00/kWh and MRAs below 9 %. BESS + PV lowers generation costs compared to off-peak rates, increasing the viability of shared usage. Integrating PV + BESS systems with rate switching significantly diminishes electricity expenses. The substantial BESS implementation cost necessitates a noteworthy rate differential for viability, which could potentially impact non-PV and non-BESS consumers. [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]

Distributed generation, which is mainly deployed with PV systems that benefit economically prosumers, has soared in use in Brazil. Despite this, PV capacity in excess may cause technical issues which concern planning engineers who have adopted rules of thumb to screen interconnection requests without any detailed study. Recently, the hosting capacity concept has been employed to assess how much PV capacity a distribution grid can host without deteriorating grid parameters, reliability, or power quality. A steady-state and worst-case-based scenario was used to run deterministic power flow simulations to estimate the hosting capacity of a specific radial circuit at a campus of the University of São Paulo, referred to as "USP-105". Although the result may be not completely accurate, it was found that USP-105 can accommodate 103% of its peak load or 4970.6 kW of PV power, which reduced the circuit's annual peak load by 9%. Another finding was that hosting capacity increased when PV-DG deployment was dispersed along the circuit rather than concentrated on a single location (e.g., closest, or furthest to the substation). Utilities may therefore benefit from a simple and quick assessment to obtain an overview of how specific circuits behave on PV deployment and indicate which locations are technically more beneficial. [ABSTRACT FROM AUTHOR]

Purpose: To explore financial alternatives to implement PV power generation projects based on the provisions of Normative Resolution n. 482/2012 of the Brazilian Electricity Regulatory Agency (Aneel). This regulation sets forth the general conditions to the access of microand minigeneration granted to the electric energy distribution systems through the energy product offset method. Originality/gap/relevance/implications: This paper discusses the need for regulatory changes, greater government participation in the granting of financial and tax incentives so that PV solar power technology in distributed generation can be financially viable for residential consumers. Key methodological aspects: Investment analysis in PV systems used the Net Present Value (NPV) valuation method. The research assessed two scenarios for Grid-Connected PV Systems (GCPVSs), with different solar power usage levels for a residential consumer. Summary of key results: The results point to a low financial viability in the implementation of distributed microgeneration projects, suggesting the need to remove the tax burden and reduce financing costs. Key considerations/conclusions: The study shows the need of flexibilization of the Brazilian regulatory model, with changes that enable the expansion of renewable energy offers, with positive economic outcomes for tariff affordability. Tariff benefits from distributed microgeneration can positively reflect on captive customers, provided that investment risks are reduced. [ABSTRACT FROM AUTHOR]

This paper proposes a new methodological framework to support the decision of Brazilian distribution companies (DISCOs) when defining maximum demand contracts with the transmission system. The contract must be established one year ahead, and several uncertainties associated to loads, distributed generation (DG) and internal grid contingency events, should be considered. The optimal contracting decision should take into account the risk profile of DISCO's stakeholders and the interest of final consumers. To tackle these topics, an engineering-based approach is proposed in which a chain of four methods composes the final solution approach. To ensure realistic and tractable solutions, load and DG time series are decomposed into low and high frequencies to address the challenge of deriving long-term probabilistic forecasts for high-dimensional time series in high frequency. The proposed methodology considers exogenous long-term trend drivers (such as economic and climatic indices) in the probabilistic forecasts of loads and DG, as well as corrective actions to respond against contingencies in the power flow simulation. Results for a Brazilian DISCO show that the proposed probabilistic forecasts are adherent and tractable. Our case study corroborates the effectiveness of our approach to support DISCOs' decision and adjust their contracts based on pre-specified risk levels. • Four integrated methods to define long-term DSO-TSO demand contracts in Brazil. • A new method for simulating high-dimensional hourly load and DG time series in a long-term horizon. • A new array of quantile regressions to estimate and simulate conditional dynamic load curves. • A risk-averse optimization model to define the optimal demand contracting strategy of a distribution company. [ABSTRACT FROM AUTHOR]

The modeling of the regulated electricity market is essential since it allows the calculation of optimal rates by the regulatory agency, resulting in maximum socioeconomic welfare. Besides that, it is also possible to predict consumer behavior based on socioeconomic models. Therefore, under rate readjustments, energy shifting can be estimated and encouraged by the regulatory agency. This paper proposes major modifications to the optimized tariff model, originally developed for constant rates and grids without distributed energy resources, to model static time-of-use rates, distributed generation, and energy storage, enabling regulated electricity market optimization. • Development of a regulated socioeconomic model for analyzing TOU rates with DG and ESS. • Development of an optimization technique to obtain maximum socioeconomic welfare. • Energy shifting estimation and promotion based on tariff manipulation. • Analysis of public incentive policies. [ABSTRACT FROM AUTHOR]

Low-voltage (LV) consumers are considered the main cause of loading the electrical systems during peak hours, hence increasing the expansion costs of the distribution system. To stimulate the efficient use of Brazilian electricity, the National Electric Energy Agency (ANEEL) established a new tariff modality for low-voltage consumers, known as White Tariff, effective in Brazil since January 2018. The White Tariff is an hourly rate with three different time schedules throughout a day. In addition to this new tariff modality, ANEEL established the conditions for access to distributed micro-generation and mini-generation since 2012 through the Normative Resolutions No. 482 and No. 687 as a way of encouragement of the inclusion of distributed generation (DG) for the low-voltage consumers. In this sense, this article aims to present a methodology to analyze the implementation of the white tariff for photovoltaic and biomass DG by rural LV consumers. The methodology consists of carrying out simulations using the hybrid optimization model for electric renewables software including combinations to consider energy tariffs from different local utilities, load profiles of rural consumers within different consumption ranges, natural resources and distributed generation technologies. From that, it is possible to conclude that the resulting simulations were more satisfactory for the white tariff together with the DG biomass for consumption within ranges from 501 to 1000 and 1001 to 5000 kWh. [ABSTRACT FROM AUTHOR]

This paper proposes a mathematical model based on mixed integer linear programming (MILP). This model aids the decision-making process in local generation use and demand response application to power demand contract adequacy by Brazilian consumers/prosumers. Electric energy billing in Brazil has some specificities which make it difficult to consider the choice of the tariff modality, the determination of the optimal contracted demand value, and demand response actions. In order to bridge this gap, the model considers local generation connected to the grid (distributed generation) and establishes an optimized solution indicating power energy contract aspects and the potential reduction in expenses for the next billing period (12 months). Different alternative sources already available or of interest to the consumer can be considered. The proposed mathematical model configures an optimization tool for the feasibility analysis of local generation use and, concomitantly, (i) checking the tariff modality, (ii) revising the demand contract, and (iii) suggesting demand response actions. The presented result shows a significant reduction in the energy and power expenses, which confirms the usefulness of this proposal. In the end, the optimized answers promote benefits for both, the consumer/prosumer and the electric utility. [ABSTRACT FROM AUTHOR]

The growth of the economy in urban centers is invariably accompanied by an increase in human activities and environmental interference, mainly related to waste generation. Due to the nature of these activities, large volumes of varied waste are generated daily without the establishment of compatible and adequate collection, logistics, and final disposal systems, bringing relevant impacts to society on health, the environment, and the economy itself. In Brazil, in 2019 alone, almost 30 million tons of MSW were not collected and the total collected, of approximately 44 million tons, went to landfills, with little or no energy use. There is therefore a great opportunity for energy use using this source, aiming not only to adapt to current legislation, but also to reduce GHG emissions, reduce the population's exposure to sanitary landfills and open air, and use the energy contained in these wastes. The purpose of this study is to analyze the main conditions and challenges of current technologies for harnessing the energy potential of biomass from urban solid waste (USW) to enable the insertion of mini thermal plants connected to distributed generation. [ABSTRACT FROM AUTHOR]

Brazilian consumers have the possibility to produce their own energy using renewable sources or qualified cogeneration and even provide the surplus for the distribution network of their locality, as determined by Normative Resolution no. 482/2012 issued by the National Electric Energy Agency (ANEEL). In view of this, the use of photovoltaic systems for electricity generation has grown surprisingly reaching the mark of 8 gigawatts of installed power on Brazilian soil in the year 2021 [1]. In Brazil, public agencies represent 0.1% with 4.7MW installed [1], and 0.38% in the state of Mato Grosso [14]. Thus, aiming at the rise of electricity generation in public buildings due to the possibility of reducing the electric bill costs, the present work deals with the dimensioning, budget quotation and economic feasibility analysis regarding the installation of a grid-connected photovoltaic power generation system to meet the energy demands of Jorge de Abreu Regional Hospital in the city of Sinop, Mato Grosso state, Brazil. After carrying out the necessary research based on the techniques present in the economic sciences, as Minimum Attractiveness Rate (MRA), Net Present Value (NPV), Internal Rate of Return (IRR) and calculation of Payback, the present work considered a grid-connected solar energy generation system of 585 kW to supply the hospital's average monthly consumption of 93.829 kWh/month. The investment analysis showed that the project for the implementation of the photovoltaic system will have its NPV viable as of the 4th year of installation and the Payback (return on investment), observing the monetary corrections, of approximately four years and five months, thus configuring the system as economic financially. [ABSTRACT FROM AUTHOR]

Abstract: The typical electrical distribution system shows a passive characteristic in relation to power flows (i.e. unidirectional power flows from substation to loads along the feeder). However, with the inclusion of solar photovoltaic (PV) generators along the feeder, this behavior is changed, and characteristics related to power quality, such as voltage level and total harmonic distortion (THD), may be affected. This paper presents the analysis of power quality in a feeder of the urban grid in the city of the Florianopolis, Brazil, with the integration of grid-connected PV systems as distributed generation. The analysis of power quality is based on real measurements of THD on an existing 12kWp PV pilot plant installed in the urban environment, and power flow simulations of a hypothetical PV system of 4.2MWp distributed in the same area, using the ANAREDE software. The power flow simulations allowed assessing the voltage level, the direction of power flow and loading of the distribution lines. The introduction of limited amounts of PV generation as distributed generation in the urban environment was found to be beneficial in several aspects: better voltage profile; power loss reduction and improvement in total harmonic distortion of the voltage (THDv). Furthermore, photovoltaics as a distributed generation source can also postpone feeder capacity upgrading investments. [Copyright &y& Elsevier]

The main objective of this research is to propose an active and reactive power injection control in order to mitigate voltage sags. The proposed control strategy works in conjunction with a modified version of an automatic voltage regulator (AVR), where it will act on the active and reactive powers injected by the inverter to reduce the effects of voltage sags. In this way, the control will avoid possible shutdowns and damage to the equipment connected to the grid. The voltage improvement can be perceived for consumers connected to the power system. Modifications in AVR model and parameters are performed to speed up its performance, thus identifying the short-duration voltage variations (SDVV) and, consequently, the control acts to alter the powers, decreasing the active power injection and increasing the reactive power based on inverter capacity during the momentary voltage dip (MVD). Finally, when the fault is cleared, all values return to the pre-fault condition, so that the inverter only operates with active power. A 75 kW three-phase grid-connected photovoltaic system (GCPVS) equipped with the proposed control was inserted in a distribution grid of the city of Palmas, state of Tocantins, Brazil, and all of the computer simulations were performed on the Matlab/Simulink®. [ABSTRACT FROM AUTHOR]

The present work analyzes the Income and Energy Generation Program, authorized by the Brazilian National Energy Agency and implemented by Caixa Econômica Federal and Brasil Solair in two condominiums of popular housing. The method used is qualitative, applied, descriptive and exploratory. An extensive literature review was conducted as well as 18 interviews with specialists, agents from the electricity sector and representatives of the condominiums. Questionnaires were distributed to all residents to understand the energy consumption habits in the condominiums and the situation experienced throughout the program execution. For the data analysis, the triangulation method was used. In the results, the situation of the residents and five different opportunities to adapt the renewable energy system of the condominiums to current legislation are highlighted and analyzed. These include the rental of roofs and equipment or building a cooperative with other beneficiaries of social housing programs for remote energy compensation. In conclusion, the project could be improved to better fulfill the needs of the condominiums and their inhabitants, guaranteeing better use of investment in renewable energy and improving programs to alleviate poverty in Brazil. [ABSTRACT FROM AUTHOR]

Brazil is currently undergoing changes to regulations on distributed generation (DG), specifically for solar energy micro-generation. The changes proposed by the Brazilian Regulatory Agency suggest that only the cost of energy be compensated to investors. The service costs and other charges related to energy tariffs must be divided among consumers. Investors with existing installations and class entities have contested these proposals, calling them "sun-fees". To date, no scientific papers have been published discussing these changes. The new regulations propose an end to cross subsidies, where all consumers (even those who do not have DG) pay for the transmission and distribution systems. This study compares the economic feasibility of micro-generation before and after implementing the new standards proposed by the regulatory agency. We used data on average electrical energy demand, energy price, and solar radiation in different regions. The national averages were used as a base comparison with other scenarios. The results show that projects are viable for all analyzed scenarios, however, after implementing the proposed changes, the discounted payback time is extended. This, however, does not make projects unfeasible. [ABSTRACT FROM AUTHOR]

The operation of electrical systems is becoming more difficult due to the intermittent and seasonal characteristics of wind and solar energy. Such operational challenges can be minimized by the incorporation of energy storage systems, which play an important role in improving the stability and reliability of the grid. The economic viability of hybrid power plants with energy storage systems can be improved if regulations enable the remuneration of the various ancillary services that they can provide. Thus, the aim of this study is to provide a literature review regarding the economic feasibility of hybrid wind and solar photovoltaic generation with energy storage systems and its legal and regulatory aspects. Observing the global tendency, new studies should address the technical and economic feasibility of hybrid wind and solar photovoltaic generation in conjunction with, at least, one kind of energy storage system. In addition, it is very important to take into account the regulatory barriers and propose solutions to remove them. It was observed that although regulatory aspects can influence the economic feasibility of hybrid projects, little is known about this relationship among regulatory frameworks. The findings presented in this article are important not only for Brazil, but also for other countries that do not have regulations in force to support the use of energy storage systems in hybrid systems. [ABSTRACT FROM AUTHOR]