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In the context of increasing integration and relevance of distributed energy resources, this paper proposes an advanced public policy to maximize their long-term benefits through optimal regulated electricity market management. More specifically, the focus is on renewable distributed generation and energy storage systems. The proposed policy arises from three models or techniques, i.e., the optimized tariff model (regulated electricity market model), Bass diffusion model (long-term forecasting of the integration of distributed energy resources), and random walk (risk assessment technique), along with a stochastic optimization problem. The policy leads to socioeconomic welfare maximization while ensuring fairness for all the market players and enhanced control by the regulatory agency on the integration of distributed energy resources. By applying the policy to a concession area located in northeastern Brazil, where photovoltaic distributed generation systems dominate the market share, results demonstrate that it is highly valuable as a 156 (MR$) mean socioeconomic welfare gain was achieved when optimizing the design variables (compared to a non-optimal solution). [Display omitted] [ABSTRACT FROM AUTHOR]

In this study, projections and current status of municipal solid waste generation worldwide and its collection, final destination, and waste-to-energy technologies are reviewed. Firstly, an overview of waste generation worldwide is presented comparing income levels and the material composition of residues in several regions. This paper focused on contrasting Brazil and Portugal in terms of waste production and its management from generation to disposal or treatment. Furthermore, it is presented a summary of leading waste-to-energy technologies such as incineration, anaerobic digestion, gasification, pyrolysis, co-combustion, co-gasification, among others. Technical aspects of these thermo-chemical, biological, and physic-chemical processes for the production of biofuels such as biogas, syngas, biodiesel, and hydrogen-enriched gases are presented. Additionally, current aspects of the waste-to-energy market are exposed regarding the major players, investments, and expectations for the future of this activity with the elaboration of SWOT analyses. Finally, a review of greenhouse gases emissions worldwide is presented, specifically from Brazil and Portugal, as well as some consequences of these pollutant gases on the society and the environment and which are the main technologies for carbon dioxide capturing and sequestration as promising solutions for lower pollutant gases concentration in the atmosphere. This review paper aims to provide information for the management of municipal solid waste in Brazil and Portugal considering the mutual objective of meeting sustainable development goals. [ABSTRACT FROM AUTHOR]

The present paper explored the effect of renewable energy, financial development, and technological innovation on the ecological footprint in Brazil using a yearly dataset stretching between 1990 and 2018. The research leverage dynamic autoregressive distributed lag, Bayern and Hank cointegration, and frequency domain causality to explore these interrelationships. The ARDL bounds test outcome confirms a long-run connection between ecological footprint and its drivers. Besides, we employed the Bayern and Hank cointegration, and the outcome resonated with the ARDL bounds test result. Moreover, the dynamic ARDL outcomes disclosed that economic progress worsens the ecosystem whilst renewable energy, trade globalization, and technological innovation lessen the ecological footprint. In addition, no significant interrelationship was found between financial development and ecological footprint. Moreover, with the exemption of financial development, all the exogenous variables can forecast the ecological footprint in Brazil. The study proposes that policymakers in Brazil should undertake investments in research and development in order to achieve technological innovation. Furthermore, since technological innovation has been shown to contribute significantly to lowering the ecological footprint, it is possible to assume that enhancing current technology is the ultimate remedy to Brazil's ecological problems. • Dynamic ARDL applied to Brazil's time series data. • Renewable energy and Technology innovation improve environmental quality. • Trade and globalization also reduce Ecological Footprints (EF). • Economic Growth contributes to higher EF. [ABSTRACT FROM AUTHOR]

Hydroelectric power plants have been losing competitiveness to renewable resources in Brazil, specifically wind and solar power resources, given the current water crisis in the country, which has left main reservoirs in the Brazilian hydroelectric power system depleted. However, other renewable energy resources show disadvantages in terms of intermittence and energy storage. Pumped Hydropower Storage (PHS) can help mitigate this problem, supplying energy with fewer variations. This paper studied using PHS concepts together with solar and/or wind renewable resources to recover water levels at the Furnas reservoir in terms of energy and economic performance. The energy studies were developed by sizing the PHS and identifying solar and wind resource potential for supplying energy for pumps in the hydropower plant. The economic analyses considered three different scenarios (I; II and III), and used the NPV (Net Present Value), and LCOE (Levelized Cost of Electricity) methods for a period of 30 years. Energy calculations showed that 1692 MWh/day of energy could be generated using PHS. However, 2729 MWh/day of energy would be needed to store generated energy, and a 1037 MWh negative energy balance will be compensated for by using daily wind and/or solar photovoltaic power production. This would allow the Furnas reservoir to regain 0.45 m of its water level per year. The economic studies showed economic viability for PHS scenarios I and III, with estimated NPV at 151.5 million dollars, and 64.5 million dollars for the last year of the project, respectively. Scenario II was unviable, giving rise to several strong discussions on this application within Brazil. • Wind and solar sources were considered for the pump energy supply. • The proposed system can recover 0.45 m/year of the level in the Furnas reservoir. • The energy production of the reversible power plant was estimated as 1,692MWh/day. • Economic feasibility was evaluated in many scenarios using NPV and LCOEmethods. • Market regulation is required for the diffusion of this technology in Brazil. [ABSTRACT FROM AUTHOR]

This paper proposes a method to assess the financial attractiveness provided by adding a Battery Energy Storage System (BESS) in distributed photovoltaic (PV) generation on public buildings in Brazil. The method is applicable to prosumer units (PU) connected on the medium voltage grid operating under time-based electricity tariffs. The BESS primary objective was to achieve optimal reductions in electric energy expenses through effective energy arbitrage mechanisms. The procedural steps of the methodology begin with an analysis encompassing assessment of solar resource, PU consumption profile, and BESS sizing and operation. Subsequently, steps entail contracted power optimization, PU net-metering analysis, and evaluation of BESS impacts on electric energy expenses. Lastly, a regulatory and economic analysis is conducted incorporation considerations on BESS taxation, behind-the-meter regulations, and a sensitivity assessment extending to the 2030 outlook. By 2050, it is anticipated that PV generation will surpass hydropower, becoming the predominant component of Brazil's energy mix. This shift is expected to create an increased need for solutions, notably storage systems, capable of meeting flexibility requirements and maintaining grid resilience. The results suggest that the financial viability of incorporating BESS becomes favourable when the battery cost is below 365 $/kWh. In approximately 50% of the Brazilian territory, prevailing economic conditions support the adoption of BESS. Nationwide feasibility of integration is anticipated for the year 2027. It was observed that government policies to exempt BESS taxation, even if temporary, would be extremely interesting to promote the widespread adoption of this technology. The 2030 outlook of the transition to these benign renewable energy technologies is already in place, and will dominate the energy mix. [ABSTRACT FROM AUTHOR]

During the last 10 years Brazil has accelerated the incorporation of new wind capacity into its power matrix. This situation has generated the need for increased transport capacity. However, there have been delays in the planning process for new transmission line construction, thus inducing trapped electricity in the system; in other words, electricity that cannot be dispatched to the interconnected system. Using system dynamics modelling, this paper assesses energy policy alternatives for improving the synchronisation between the construction of both power generation and transmission capacities. Simulation results show that policy synchronisation within the wind industry may provide important opportunities regarding security of supply. This paper concludes that in Brazil's case it is possible to attain a balance between wind power expansion and interconnection capacity through synchronised and systemic interventions. • Power systems require a sustainable balance between supply and demand. • Wind power industry could be affected by energy policy fragmentation. • This article assesses alternative policy options to contribute to the existing literature on grid congestion. • New insights on the synchronisation of energy policies for the wind industry expansion is offered. [ABSTRACT FROM AUTHOR]

The use of wind power has gained prominence on the world stage, especially in Brazil. In addition to generating energy free of emissions, wind technology is the second cheapest generation option in Brazil. At the same time, it has contributed to reducing hydrological vulnerability caused by climate variation. Although wind power has experienced a steady expansion in the last decade, recent poor outcomes of wind auctions produced uncertainty about the future of this technology in the country. This paper analyses the influence of contract mechanisms used in Brazilian energy auctions for the growth of wind generation. To do this, a scenario analysis based on a hybrid simulation model is used, combining agent-based modelling (ABM) and system dynamics (SD). From the hybrid simulation, the effect of the wind project cancellation policy is analysed, on the one hand, and different ceiling prices for competing sources in the auctions are assessed, on the other. Moreover, the simulation model shows how hydro conditions affect reserve energy auctions. [ABSTRACT FROM AUTHOR]

This paper performs Fourier cointegration and causality tests to analyze the effect of renewable energy generation, globalization, and agricultural activities on ecological footprint and carbon dioxide (CO 2) emissions in BRIC countries for the period 1971–2016. The Fourier ADL cointegration test supports a long-run relationship between the considered variables in Brazil and China. The long-term elasticities indicate that globalization increases the pollution indicators, while renewable energy generation significantly reduces environmental pressure in China. Moreover, globalization increases CO 2 emissions, while renewable energy generation improves environmental quality in Brazil. The causality results show the existence of bidirectional causality between agriculture and environmental degradation; unidirectional relationships from globalization to the ecological footprint and CO 2 emissions; and renewable energy generation to the ecological indicators. Overall, these findings reveal the importance of renewable energy in combating environmental degradation. Based on the above results, renewable energy generation can significantly reduce environmental pollution in Brazil and China. However, renewable energy does not affect environmental pressure in Russia and India. Therefore, these countries should differentiate the current renewable energy generation policies to achieve their sustainable development goals. [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]

Abstract This work analyzes the impacts of climate change in the revenues of hydropower plants. One important input for designing and evaluating investment opportunities in hydropower is the water inflows historical data. Unfortunately, the use of such information alone may not project well the future power generation due to the influence of climate change in the water inflow patterns. This paper introduces spatio-temporal information of the future climate into the operational planning of the Brazilian hydropower system. Global climate models from IPCC are considered along with downscaled regional climate models. Our results at the individual hydro plant level show the importance of taking into account climate change information when performing hydro generation planning studies. Highlights • We present a new framework to evaluate climate change impacts in hydropower plants. • An interaction among regional climate, water inflows modeling, and optimization dispatch models is showed. • Relevant results for distinct configurations of the Brazilian system are presented. • This paper can help to support decision-making regarding investments in new hydro plants. • This multidisciplinary research provides guidance for future planning of the generation system. [ABSTRACT FROM AUTHOR]

One of the challenges of energy regulatory-agencies is to guide the agents decision-making process towards maximization of the overall welfare of the electricity sector. However, this is not a simple task since it requires meeting expectations of many stakeholders, from investors to consumers. This paper proposes an optimization methodology aimed at helping define the optimal combination of wind farm layout and type of equipment deployed, so that the electricity sector overall welfare is maximized in the process. The optimization objectives are (i) the energy density and (ii) the Net Present Value (NPV), and the parameters are (a) the power levels and (b) the selling price of the energy. The objective functions are modelled with the aid of a design-of-experiment technique known as Response Surface Methodology, relying on the multi-objective programming method of Normal Boundary Intersection for the optimization. The methodology is applied to four different scenarios arising from the combination of two different locations (Santa Vitória do Palmar-RS and Macau-RN, both in Brazil), and two different wind turbine manufacturers (A and B). The final step comprises the application of the Data Envelopment Analysis technique in order to sort one from the set of optimal solutions identified by the four different scenarios. The results show that the proposed methodology is capable of supporting bidding processes and wind farms certification programs, in line with what should be expected by regulatory agencies, investors and electricity consumers alike. The deployment of the methodology proved discriminant and allowed selection of one final scenario (Macau-RN, brand A equipment) as overall optimal. It was also observed that equipment efficiency is dependent on siting location. • A multi-objective optimization method for wind farm planning is proposed. • A trade-off between socio-environmental and technical-economic aspects is solved. • Association of NBI-RSM-DEA designs is a novelty for energy planning optimization. • The behavior of different turbine brands in different regions is investigated. • Results show that wind farm configuration can be optimized from multiple objectives. [ABSTRACT FROM AUTHOR]

This paper investigates the local complementarity of three types of renewable sources (solar, wind and tidal). One of the main drawbacks of non-conventional renewable energy sources is their intermittent nature. Wind energy depends on the wind speed, which varies throughout the day. The generation of photovoltaic solar energy is strongly affected by clouds, that cause an abrupt drop of power to less than 50% of its rated capacity. In contrast, tidal energy is characterized by a high degree of predictability. This article raises important features of local complementarity of these renewable sources. These properties can be exploited to improve the firm power of isolated microgrids, leading to a variety of beneficial operational consequences. The contributions and conclusions presented here are supported by case studies and real data measured in the coastal region of northern Brazil. [ABSTRACT FROM AUTHOR]

Over the past few years, there has been a growing global consensus related to the importance of renewable energy to minimize the emission of greenhouse gases. The solution is an increase in the number of renewable power plants but unfortunately, this leads to a high dependence on climate variables which are already affected by climate change. Brazil is one of the largest producers of electricity by renewables through its hydro-dominant power generation system. However, hydro-generation depends on water inflows that are directly affected by climate change that consequently affect the electricity production. Therefore, these changes need to be considered in the operation and planning of a hydro-dominant power system. In this paper, we present the effects of different climate scenarios in the water inflows produced by the regional Eta climate model. Normally, studies use an optimization model to make decisions in case of a hydro-thermal scheduling problem and use the assured energy to evaluate the hydro-production. In this analysis, water inflows used in the optimization process consider different trends according to its associated climate scenario. Our paper shows that climate change may drastically impact the system assured energy and consequently, the system's capability to supply load. [ABSTRACT FROM AUTHOR]

Only in the present decade, Brazil has begun to adopt assertive policies and regulatory tools to stimulate the implementation of photovoltaic (PV) generation systems. Available information concerning the support to PV generation and the behavior of different technologies under the environmental conditions are still scarce. This paper analyzes an existing method to estimate PV energy performance and proposes a new model to evaluate six different types of grid-connected photovoltaic technologies. The proposed model considers PV technological features together with the actual characteristics of the operating settings and climatic conditions of the experiment site at the Lake District, Rio de Janeiro, Brazil. Results from multiple regression analyses evidence that the existing method is not suitable for PV energy predictions under the environmental conditions of the region. The proposed model was able to obtain satisfactory answers to the tests developed and good results with measurements taken in field. The results endorse the model as a good estimator of energy performance of the six photovoltaic technologies evaluated in the aforementioned region. In addition, it might be used in other types of photovoltaic technologies and in different regions. [ABSTRACT FROM AUTHOR]

The increasing supply of non-conventional oil in the U.S. has changed the dynamics of crude oil market and the flow of oil products in the Atlantic Basin. The Gulf of Mexico (GoM) emerges as an exportation hub of oil products, contributing to a scenario in which gasoline prices tend to decline. Meanwhile, from 2010, the competitiveness of the Brazilian sugarcane ethanol has been ruptured by the country's gasoline price policy that had not followed international price parity. The political conjuncture of the U.S. incites high utilization rates of their refining system in the GoM. In this context the profitability of the ethanol business can be impacted in Brazil, by either the current policy of controlled domestic gasoline prices or a future scenario of declining gasoline international prices. Therefore, this study tests if this gasoline price scenario can compromise even more the competitiveness of the Brazilian ethanol. Particularly, for a scenario of falling prices, ethanol production in Brazil would be under strong pressure of gasoline supply coming from the U.S. This can impact Brazil's ethanol industry, whose development has been justified by climate change policies. In that sense, the paper also discusses the future opportunities and challenges for Brazil's ethanol industry. [ABSTRACT FROM AUTHOR]

This paper forecasts the supply curve of non-conventional renewable technologies such as wind and solar generating stations in Argentina, Brazil, Chile and Mexico using technological and economic parameters. It also estimates the additional investment costs in solar and wind generation for reaching the renewable energy target in each of these countries. To assess the power supply profile from 1 axis tracking PV and horizontal axis wind turbine (three blade) stations, two different scenarios are developed for 2014 and 2025. Scenario 1 estimates the PV and wind annual electricity yield by using polycrystalline silicon (cSi poly) as semiconductor material for PV cells and a Vestas 90–3.0 MW turbine for the wind for 2014. Scenario 2 assumes a more efficient technology, such as CPV. In fact, the model employs 45% efficiency triple junction cells using ∼3500 m2 for each 1 MW installed capacity in 2025. Moreover, this scenario also assumes a more powerful type of turbine, i.e. Vestas 112–3.075 MW. The biggest potential for wind power is found to be in Argentina, followed by Brazil, Mexico and Chile. In addition, a 550 MW installed capacity CPV power station, using triple junction cells could generate up to 4 TWh in Chile in 2025. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents a proposal of sustainable management model alternative for electrification of remote communities in the Amazon region, considering the Brazilian regulation policy. This paper presents also a case study of the electrification in a river-dwelling community in the State of Pará, Brazil, within the scope of the Program for Electric Power Service Universalization in Brazil. The community shall be provided with electrification facilities through a small biomass-based power plant, directly firing residues produced by the local economic activity. The objective of the paper is to make a proposal for a sustainable management model that is suitable for the community’s isolation conditions, considering the high costs with operation and maintenance related to the supply for isolated consumers in small locations. A simulation is conducted for the operation of the small biomass-based power plant; the generation costs are determined; the legal aspects are analyzed; and a suggestion for the management model is presented. [Copyright &y& Elsevier]

Proposing solutions for potable water supply in semiarid regions such as Brazil's Northeast region is of great importance. In addition to the water shortage, the lack of chemical and biological quality in the water is another difficulty to be faced. Taking advantage of the high levels of solar irradiation in those regions, the use of solar systems for water treatment is possible. In this paper, an automated solar pasteurizer system was used for the microbiological decontamination of water. The main characteristics of the solar pasteurizer are energetic self-sufficiency and robustness, the ability to promote decontamination regardless of the turbidity or pH, absence of production of trihalomethanes, local biome preservation (Caatinga), control of treatment time and the absence of secondary contamination derived from the mixture of contaminated water with water in treatment. The system was able to treat the water in pre-programmed temperatures and time intervals of 3600 s at 55 °C; 2700 s at 60 °C; 1800 s at 65 °C; 900 s at 75 °C; and 15 s at 85 °C. The microbiological analysis performed (presence/absence of Total Coliforms and Escherichia coli ) indicated the efficacy of the system, making it suitable for water treatment. It was found that productivity (batches' frequency) is directly proportional to accumulated irradiation. The pasteurizer is able to treat the water starting at the solar irradiation level of ≥12.2 MJ/m 2 for systems without a heat recovery exchanger. The use of a heat recovery exchanger in this system, to pre-heat the water at the collector's inlet, is of great importance because it induces an increase in productivity of approximately 50% (highest productivity reaching 30 L in a day) and lowers the minimum level of solar irradiation 8.3 MJ/m 2 . [ABSTRACT FROM AUTHOR]

The onshore wind power is consolidated; the challenge is to reach the same level of maturity for offshore exploitation. Brazil has no offshore wind power plants and there are few studies in this direction. This paper aims to estimate the offshore wind resources in the State of Ceará, in Brazil. The investigation uses a mesoscale atmospheric computer model, the Regional Atmospheric Modeling System (RAMS), with horizontal resolution of 2 km, which estimates the offshore average wind speed, average wind direction, power density and turbulence taking into account the bathymetry data and navigation routes along the coast of Ceará. The wind potential was evaluated in three representative periods, La Niña, El Niño and Neutral year, analyzing the dry and rainy season for each period. The results indicate an average wind speed above 8 m/s and power density above 720 W/m 2 no matter the period evaluated, in the dry season. The predominant wind direction in the observed dry periods was from East to West and the turbulence intensity is smaller during dry season of El Niño. Besides, the bathymetry of the State of Ceará is shallow and the large ships route is far beyond the coast, offering no danger to future endeavors. [ABSTRACT FROM AUTHOR]

The Brazilian territory is irradiated with solar energy ranging from 1500 to 2300 kWh/m 2 /year, compared to 900 to 1850 kWh/m 2 /year in Germany, France, Italy and Spain. Despite that, photovoltaic (PV) technology is only now starting to penetrate the Brazilian electricity mix. Until recently, the high costs of PV generation had prevented this technology from competing in Brazil. However, the consistent PV price reductions and the worldwide scale reached, has brought attention to the Brazilian planners and actions have been taken recently in Brazil to help PV start its progress. In this paper, two of the recent government actions are analyzed, namely the National Electrical Energy Agency ANEEL Resolution RN482/2012, and the announcement of support by the Brazilian Development Bank offering loans at low interest rates for solar PV projects. The effects of these actions for residential PV systems are positive where the conventional electricity tariff is high with respect to the average in the country, and less relevant elsewhere. We compare these tariffs with the calculated Levelized Cost of Energy of rooftop PV generation. The influence of these policies on the return on investment of residential rooftop PV generation is studied for different climatic zones in Brazil. [ABSTRACT FROM AUTHOR]

Abstract: Vehicle-to-grid (V2G) energy transfer in a smart grid environment opens a new revenue opportunity for electric-drive vehicles (EVs), and might reduce grid operation costs in demand-constrained urban feeders where peak-electricity prices are high. This paper analyses the peak demand energy market for V2G in the urban region of Florianópolis, Brazil. The article describes known V2G-concepts and introduces two different dispatch strategies developed for the Brazilian energy market in the light of new tariff regulations, which are expected to go into effect starting in 2014. It turns out that electric-drive vehicles may be used as a grid-stabilisation strategy, but the announced tariff regulations may lead to a destabilisation if there are too many cars offering their internal storage for V2G grid support. Adequate energy policy strategies must be introduced to avoid the conflicting interests that might stem from the different perspectives of grid operators and EV owners. In contrast to previous analyses, this research assumes the battery degradation as a function of depth of discharge (DOD), which is known for a specific battery. [Copyright &y& Elsevier]

Abstract: Photovoltaic (PV) generation depends directly on the amount of radiation received by solar modules at a given temperature, and annual irradiation varies according to site location and PV array position. In this paper, the limitations and the solar irradiation levels received by building surfaces in different positions (with azimuth and tilt angle variation) in capital cities in Brazil are shown, making use of the Brazilian global horizontal solar irradiation data provided by the SWERA (Solar and Wind Energy Resource Assessment) project. These data were processed to generate figures on the irradiation at various PV module orientations and slopes for each city, which show the relative radiation levels received on specific azimuth and tilt angles in relation to the ideal position. Results were validated using four real and operating PV systems. In general, variations in azimuth or slope did not cause large annual irradiation losses up to around 20° tilt angles. This shows to PV system planners that under these fairly flexible conditions it is possible to install PV on any orientation, keeping high levels of annual irradiation, and that limitations in orientation and tilt can be relatively low. It also allows a quick analysis of PV retrofit in building-applied photovoltaics (BAPV), when seeking the best building surfaces to incorporate PV. [Copyright &y& Elsevier]

Abstract: Biomass has become important as an alternative to fossil fuels and as a means to decrease greenhouse gas (GHG) emissions, particularly in tropical regions such as Brazil. Therefore, the demand for energy crops has increased strongly, and among such crops, palm oil is distinctive because of its productivity and well-developed production techniques. This paper intends to evaluate crude palm oil's GHG balance through a life-cycle assessment approach. This study is based on the average data of an ideal palm oil system in the northern region of Brazil. In the production of crude palm oil, a large amount of CO2 sequestration occurs during the growth of palm oil trees. In contrast, the greatest emissions are biotic CO2, which returns to the atmosphere and emissions from fertilizer production. The GHG balance of an oil palm plantation is approximately −208 kg CO2-equiv./1000 kg crude palm oil per year. [Copyright &y& Elsevier]

Abstract: A hybrid renewable energy system (HRES) uses several kinds of sources, including wind and solar, to make better use of the natural resources in standalone applications. A common application of HRES is in remote communities, where interconnected electrical grid is unreachable due to economics and physical reasons. Due to the long distance and difficult access to these isolated areas, electrical generation systems used in these applications must be reliable. And the reliability of the system, especially the inverter used to regulate the AC voltage, is one of the main problems associated to these systems, and it is responsible for the lack of confidence in renewable systems at several locations in Brazil. This paper shows the results of using renewable hybrid systems specially designed for isolated areas, focusing attention on reliability, efficiency and expansion flexibility. It presents the system description, mode of operation, inverter design, and experimental results measured in a pilot plant located in Lençóis Island, a small isolated community in the north region of Brazil. [Copyright &y& Elsevier]

Abstract: After the introduction of flexfuel vehicles in Brazil, hydrated ethanol and gasohol (gasoline blended with anhydrous ethanol at an average volumetric proportion of 75:25) became basically perfect substitutes. This paper tests the hypothesis that hydrated ethanol prices follow the price of gasohol in Brazil (opportunity cost of ethanol). In addition it tests the hypothesis that gasoline ex-refinery price variation in Brazil tends to follow the variation in the Brent crude spot price. By testing these two hypotheses simultaneously, this study test a more general hypothesis that expresses the influence of Brent spot prices on hydrated ethanol prices in Brazil (second order effect). Findings indicate that a variation in the Brent spot price does not automatically cause a variation in gasoline ex-refinery prices in Brazil. The best correlation found was between the Brent price fluctuation and the six-month average gasoline ex-refinery price. In case of gasohol and ethanol pump prices, this relation is elastic over the long and short-term in the Brazilian market. However, the short-term elasticity is greater than that over the long run. [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 presents a wind energy assessment and a wind farm simulation in the city of Triunfo in the state of Pernambuco in the northeast region of Brazil. The wind data were obtained from the SONDA (Sistema de Organização Nacional de Dados Ambientais) project’s meteor station (wind speed, wind direction and temperature) at both heights of 50 m during a period of time of 30 months. The Triunfo wind characterization and wind power potential assessment study shows an average wind speed (V) of 11.27 m/s (predominant Southeast wind direction), an average wind power density (P/AT ) of 1.672 W/m2 and Weibull parameters shape (K) and scale (A) respectively equal to 2.0 and 12.7 m/s. Those values demonstrate an important wind potential in this region for future wind farm prospection. The wind farm (TRI) was simulated by using 850 kW wind turbines given a total of 20 MW installed. The simulated results show(s) an AEP (annual energy produced) of 111.4 GWh, a capacity factor (Cf ) of 62% and a total of 5.462 h of operation by year (full load hours). The economical simulated results show(s) a Pay-back of 3 years Internal Rate of Return (IRR) of 47% and Net Present Value (NPV) of 85.506 k€ (both in a period of time of 20 years). [Copyright &y& Elsevier]

Abstract: The availability and reliability of wind power depend a great deal on current and future climate conditions, which may vary in light of possible global climate change (GCC). Long-term energy planning, however, does not normally take possible future GCC into consideration, which may turn out to be a risky exercise. In the case of Brazil, the untapped wind power potential is known to be impressive, provided that climate conditions remain the same over time. The focus of this study is to analyze some possible impacts of GCC on the wind power potential of Brazil, by simulating wind conditions associated with the IPCC A2 and B2 Scenarios. Results based on the HadCM3 general circulation model and the analysis of the country''s wind database indicate that the wind power potential in Brazil would not be jeopardized in the future due to possible new climate conditions. On the contrary, improved wind conditions are expected, particularly in the Northeast coast of the country. Therefore, investments in wind power generation can be an interesting way to expand renewable energy production in Brazil. However, given the large uncertainties associated with GCC models and scenarios, the findings of this paper should be viewed as a possibility rather than as a projection. [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]

Abstract: Brazil''s wind power potential is impressive. The incentive policies that have being implemented in the country, since the last decade, promoted the implementation of some projects, mainly through the Alternative Energy Sources Incentive Program (PROINFA), which started in 2002. After the first phase of PROINFA, the wind power sector in Brazil is still waiting for a new long-term program. By applying a GIS model to the available wind database, this paper evaluates three long-term incentive programs to wind power in Brazil, according to specific targets and criterion. The first target was to reduce the emissions of greenhouse gases from the electricity generation, through the replacement of fossil fuels fired-thermal plants. In this case, an incentive program based on quotes and permits would install a wind capacity hovering between 18.7 and 28.9GW. For the target of optimizing the operation of Brazil''s hydropower reservoirs, a program based on feed-in tariffs would result in the installed capacity of 15.5–65.4GW, depending on the criterion for selecting the projects. Finally, considering only the target of fostering a domestic wind technology industry, the installed capacity would vary between 29.1 and 217.1, depending on the criterion for selecting the projects. [Copyright &y& Elsevier]

Appropriate information on solar resources is very important for a variety of technological areas, such as: agriculture, meteorology, forestry engineering, water resources and particularly for an innovating technology such as solar energy. In the market entry process of an innovating technology such as solar energy, the enlarged and sustained reproduction of this energy strongly depends on the economy and reliability of the demonstrative solar systems installed (within a restricted or wide scale). The economy and reliability of a system are the consequence of a well-prepared project, resulting from an accurate knowledge of the solar resource available. Therefore, knowing the potential of the solar resource accurately is not only a need, it is also an imperative for a larger diffusion and use of the solar energy.The existing sources of information on radiation in Brazil are quite varied, both at the institutional level and in different types of publications. At the institutional level these sources are: the National Institute of Meteorology, secretary of agriculture, research centers, universities, and electric power generating and distributing companies, among others. The publications with this information are project reports, internal reports of institutions or several magazines. Thus, the quality of the data varies considerably, the information presents spatial and temporal discontinuity and the instruments as well as the measurement units are not standardized.The general objective of this paper is to recover, qualify, standardize and make available the best information from the current existing solar resource in Brazil, either in the form of isoline charts of solar radiation, insolation, numeric tables or analytic summaries of a great part of the publications on the theme over the last forty years. [Copyright &y& Elsevier]