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Habitat fragmentation due to dams is a well‐known threat to freshwater fish. Yet, the global consequences of fragmentation for the viability of freshwater fish populations are unknown. Here, we provide the first global assessment of the threats of dams to the persistence of freshwater fish species. We developed a global macroecological relationship between freshwater fish range size and body size and used this relationship to assess whether isolated range fragments are too small to support a species. Our assessment includes 7369 freshwater fish species and considers the effects of 31,780 dams globally. Furthermore, we performed a more detailed analysis of the threats of dams in Brazil, the greater Mekong region and the United States, using complementary national and regional data sets. Globally, more than half of the species analysed face extirpation in a part of their geographic range, with an average potential range loss of 3.3% (95%‐range: 0%–31.8%) across all species analysed. For 74 fish species, occurring in Brazil, China, India, the Mekong basin, the United States, South‐Africa and the East Adriatic Coast, more than 50% of their range is potentially lost. This includes 18 species threatened with extinction across their whole range. Our complementary regional analysis revealed that the potentially lost range increases by a factor of 2–4 when considering both large and small dams compared with considering only large dams (≥15 m), highlighting the need to establish more comprehensive global dam inventories. Our novel approach and global analysis identifies species at risk of extirpation as well as geographic hotspots of extirpation threat by dams, which can aid in establishing more effective strategies for global hydropower development and barrier removal efforts to optimise the trade‐offs between biodiversity conservation and the socio‐economic benefits of dams. [ABSTRACT FROM AUTHOR]

Severe droughts, water-use conflicts, and minimum outflow requirements have caused infeasibilities in modeling large-scale complex hydrothermal systems. This paper presents and discusses a new formulation of objective function and constraints to better represent multiple water uses and deal with infeasibilities in the HIDROTERM model, a nonlinear programming (NLP) model developed to optimize the operation of the Brazilian interconnected hydrothermal system. The system is one of the largest in the world. In the last 10 years, approximately 72% of electricity consumed in Brazil has been supplied by hydropower plants, but with increasing shares from thermal, wind, and, more recently, solar power generation. Because of hydrological changes in recent years and the additional operational constraints imposed by environmental agencies, the use of models for decision making, such as HIDROTERM, frequently encounters the problem of infeasibility. To avoid this problem, a new objective function is proposed in HIDROTERM that incorporates economic penalties when the preset requirements are not met. Based on economic considerations, some hard constraints are removed from the constraint set and added to the objective function as penalty terms. These constraints are tightly linked with multiple water uses, including environmental protection, flood control, consumptive uses, and navigation purposes. The proposed change in the objective function and constraints avoids the problem of infeasibilities and makes it possible to apply the model to extreme conditions. Additionally, this formulation helps identify and minimize the risk, duration, and intensity of unavoidable non-compliance occurrences related to multiple water uses. The presented new version of the HIDROTERM model can be used to study and support decision making in the management and operation of large-scale hydrothermal systems. These systems can be formed by a set of hydraulically connected individual hydropower plants and reservoirs, located within a set of electrically connected subsystems. Each subsystem contains demands and other power plants, including thermal, wind, nuclear, and solar plants, and exchanges. The model has been developed with continued improvements since 2008 and applied to large systems such as the Brazilian Interconnected Power System (BIPS) with over 150 reservoirs. A graphical user interface is provided. The objective function is to minimize the total costs of additional thermal dispatch and exchanges, as well as avoid or minimize deficits in energy supply in subsystems, minimum releases, consumptive uses, and minimum storages in reservoirs. The decision variables are the power and nonpower releases for each hydropower plant and the thermal dispatches and exchanges for each subsystem. Some typical applications include (1) monthly planning operation of the system, considering a planning horizon from 3 to 5 years; (2) diagnostic studies about reliability and resilience of existing systems, processing the same system configuration to a set of different hydrological or energy demand scenarios; (3) impact analysis of changes in operational rules and constraints related to multiple uses of water; and (4) planning and evaluation of expansion alternatives. The model can be applied to a complete hydrothermal system or subsets of it, including subsystems, basins, cascades, or a single hydropower plant. [ABSTRACT FROM AUTHOR]

Leakages in water distribution systems (WDSs) profoundly affect their operations, elevating water production demand and treatment and pumping costs. Moreover, they strain the energy system by increasing power requirements at pumping stations. In regions heavily reliant on hydropower, such as Brazil, there is a nuanced implication: diminishing reservoir water levels due to increased WDS flow withdrawal. This not only immediately affects hydropower generation by reducing available head but, over time, may lead to interruptions in hydropower generation. This paper investigates the water–energy nexus, specifically focusing on WDS leakages in Brazil. It begins with an overview of the current situation and future outlook, considering evolving policies to enhance WDS efficiency and also the evaluation of different climate change scenarios. A more in-depth case study explores a reservoir utilized for both energy and water production. In this context, leakage management assumes critical importance, given the various water uses within the reservoir that impact the available energy and water resources. Overall, this study offers a comprehensive perspective on the water–energy nexus within WDSs, underscoring the critical importance of leakage control and its direct and indirect consequences, particularly on energy generation capacity, the environment, and the economy. [ABSTRACT FROM AUTHOR]

The Brazilian Amazon is marked by attempts at infrastructure-driven development. The construction of the Belo Monte dam, the third-largest in the world, brought chaotical and rapid urbanization to surrounding cities. This paper answered whether the Belo Monte dam impacted the level of violent crime in the region after Altamira was ranked as the most violent city in Brazil in 2015. Following a difference-in-difference approach, I explore the timing of the Belo Monte dam construction and the distance from the construction site to identify the causal effect of unplanned urbanization on homicide rate. In two exogenous shocks, the beginning (2011) and the end of the construction (2015), I estimated a significant rise in the homicide rate in closer cities. The results are driven by criminal activity, with drug trafficking being one of the channels behind the rising homicide rate during construction. The homicide victims are mainly the young male population causing a significant loss of human capital. The increasing homicide rate after the end of the construction indicates that the Belo Monte dam may have a long-term effect on the violence level in the region. Violence imposes high social costs and may jeopardize future growth in the Amazon. [ABSTRACT FROM AUTHOR]

Despite massive environmental impacts and socioeconomic risks, hydropower dams continue to be widely adopted and unquestioned in developing countries. This study analyzes two decades of mainstream media coverage of dams in Brazil, where two-thirds of energy consumption comes from hydropower. Through a content analysis of news articles published by the largest outlets in the country, we found coverage has relied on official and construction companies' voices and focused on economic progress, bureaucracy, corruption, and partisan politics. News rarely covered the socio-environmental risks and impacts caused by dams or questioned the country's reliance on hydropower. Overall, newspapers presented dams as highly necessary projects for national progress, conforming to a modernization-oriented mindset prevalent in newsrooms when it comes to coverage about energy. As a result, journalism has contributed to the invisibility of the struggles faced by people and the environment directly impacted by hydropower dams. [ABSTRACT FROM AUTHOR]

The São Francisco River Basin plays a critical role in the hydroelectrical operational planning of Brazil. Understanding the hydroclimatic dynamic regime and, consequently, related climate changes is essential for decision-makers of the hydroelectrical sector. In this context, the Xingó hydropower plant and its drainage area are taken as a reference for the hydroclimatic features analyzed in this research. Observed rainfall in the drainage basin and streamflow measurements in the power plant between 1975 and 2016 are used to assess the climatology of the region and to identify trends in the time series. In addition, a methodological framework based on numerical modeling of the hydroclimatic variables is employed to examine the representation of the present climate (1961 to 1990) and to investigate the future projections (2011 to 2100). The outputs from the Eta regional climate model runs driven by two global models are adopted in this case under the RCP4.5 and RCP8.5 IPCC scenarios along with the SMAP rainfall-runoff model. In Xingó, the average annual precipitation is about 978 mm and the average annual streamflow is 2,534 m3 s−1. The size of the Xingó HPP drainage area must be considered, as the rainfall that occurs in a given month can influence the streamflow of the following month. There is no trend regarding precipitation, while the streamflow time series show a statistically significant decreasing trend in the present climate. Climate projections point to an elevation in air temperature and a reduction in rainfall and streamflow by 2100. Most scenarios indicate that the average annual streamflow could be extremely low for nearly half of the twenty-first century. The results shown in this work may contribute to scenarios for operation of the Xingó HPP and support with information for planning decisions on country's energy security in the present and future climates. [ABSTRACT FROM AUTHOR]

Perspectives on the Environmental Implications of Sustainable Hydropower gathers scientific papers from three of the worlds most important hydropower producers to discuss aspects of sustainable hydropower and the means by which it can be studied and achieved. The papers examine the application and use of new technologies and protocols for studying hydropower, adaptive management and the implications and use of long-term data sets for minimizing hydropower impacts on fish populations. The papers include a cross section of biological and hydrological experts. The implicit among country comparisons highlight a number of common hydropower themes, particularly the need to expand from single species studies to include broader consideration of the ecosystem, the importance of maintaining habitat, trait and species diversity and the need for consistently collected long-term data sets. [ABSTRACT FROM AUTHOR]

The Brazilian Amazon has long served as a site of infrastructure development and natural resource extraction. Development projects including dams and mines have largely benefited distant urban actors at a cost to local communities and the environment. We draw from theories of internal colonialism and environmental justice to examine the ways that dam building undermined the well-being of communities affected by construction of the Belo Monte Dam, and to understand how those communities engaged in collective action to minimize negative impacts on their livelihoods. Drawing from semi-structured interview and ethnographic data, we find that farmers and fishers impacted by Belo Monte used a variety of tactics to resist exploitation and ultimately receive more equitable compensation for their losses. We propose two processes that were central to their success in mobilizing for environmental justice: transformative resistance and collaborative claims-making. [ABSTRACT FROM AUTHOR]

Hydropower reservoirs designed and/or operated to provide multiple services beyond power generation are called multiple‐use reservoirs. However, their construction has social and environmental impacts that require technical knowledge, social discussion, and acceptance by the public. The present paper analyzes the roles of the strategic environmental assessment and the hydroelectric inventory studies, as well as proposes alternatives for water distribution. The purpose of this study is to focus on the initial phases of hydropower planning, with the aid of the SHARE concept, in order to avoid future conflicts in the use of water resources. Although the instruments analyzed provide for the participation of different sectors, there is still little integration and alignment with sectoral policies (electrical and environmental) or there is no institutionalization of them, which makes this an urgent problem. The diagnosis resulting from this study is that the situation of multiple‐uses reservoirs in Brazil still deserves significant advances. As a proposal for improving the framework, this study claims that the use of integrated planning between sectors that use water resources should be improved by applying new concepts of integrated planning, such as the SHARE concept. [ABSTRACT FROM AUTHOR]

The history of conservation of the Amazon can be viewed as a war involving many battles with interests in agribusiness on one side and in biodiversity conservation and sustainability on the other side. Trends in large‐scale deforestation in the 1970s spurred a series of policies, stakeholder alliances and international and grass‐roots movements, which decades later led to the establishment of protected areas and interventions in soy and beef supply chains of agribusiness. Together, these advances epitomized a conservation framework for the Amazon, which at one point nearly curbed deforestation in the Brazilian Amazon, although it included very few protections for freshwater ecosystems.While those conservation advances were taking place, however, a series of policy changes started to undermine them through expansions in deforestation, river regulation and mining activities. The election of Brazil's President Jair Bolsonaro in 2019 then hit the Amazon conservation framework much like a tsunami of policy setbacks and the re‐establishment of the economic policies that sparked the Amazon war in the past.The current trajectory is one of large‐scale degradation of Amazonian ecosystems and biodiversity with consequent impacts on local people. Because freshwater ecosystems are highly sensitive to human activities on water and on land, these growing impacts are particularly large.It is too early to know, but four decades of institutional and policy developments to conserve the Brazilian Amazon may soon be pushed past the point from which they will be able to recover. Four conditions will be pivotal to allowing the Amazon conservation framework to recoup: (a) the end of Bolsonaro's mandate in 2022 or earlier; (b) remobilization of stakeholders; (c) investments in environmental research, policy and multiple collaborations; and (d) moving conservation beyond terrestrial landscapes to also encompass freshwater ecosystems and their people. [ABSTRACT FROM AUTHOR]

Hydropower may be a low-carbon option to increase power generation in developing countries, but these countries are some of the most vulnerable to climate change. Climate change can affect hydropower generation through changes in the timing and magnitude of precipitation, rising temperatures, and glacier mass changes. Evaluating climate impacts on hydropower generally requires detailed local input data and hydrological models, which may not be available in many developing nations. Nevertheless, the need to understand the impacts is essential for the developing world. Here we present a modeling framework that relies on remotely sensed and global gridded datasets forced by an ensemble of 21 general circulation models (GCMs) under two representative concentration pathways (RCPs) to evaluate climate-induced impacts on hydropower through the 21st century. We include 134 hydropower plants (>100 MW), representing 42% of hydropower installed capacity in South America, across five regions of Brazil, Colombia, and Peru. Our results suggest the median monthly usable capacity would increase for Colombia (+2.6% to +8.4% for RCP 4.5 and 8.5, respectively) and Peru (+6.7% to +9.3% for RCP 4.5 and 8.5, respectively) by 2100 relative to the late 20th century. For Brazil, we observe a mix of reductions and increases in usable capacity. While our results suggest potential reductions for the dry season usable capacity in the Parana, Paraguay, and Southeast Atlantic regions of Brazil, we also observe slight increases in usable capacity during the rainy months for all its regions. These results can help inform future planning decisions and potential interconnections between the three countries. Additionally, the proposed framework can contribute to an increased capability to evaluate climate-induced risks to power systems in developing countries, where data and computation resources can be limited. [ABSTRACT FROM AUTHOR]

Energy security is an issue at stake in governments all over the world, and also in Brazil. Although the country's energetic matrix is largely based on hydropower sources, the need for diversification is increasingly needed. The possibility of hybrids between hydropower and wind power for hydrogen production emerges as a clean alternative source for energy security. In high-throughput seasons, excess energy could be used to produce hydrogen, which could supply shortages of energy. This study shows the potential for producing hydrogen in Brazil, using excess energy from hydroelectric and wind farms. Taking into account one hour per day of surplus energy production, it would be possible to generate 6.50E+09 Nm³.y−1 of H 2. On the other hand, considering two and three hours, the H 2 generation would be equal to 1.30E+10 Nm³.y−1 and 2.00E+10 Nm³.y−1, respectively. This study calculated the economic viability for hydrogen production, at a cost of 0.303 USD.kWh−1, a higher cost if compared to that of the wind and hydroelectric plants. • Hydrogen production using excess energy from hydroelectric and wind farms in Brazil. • 3 h of production per day using surplus energy would generate 2.00E+10 Nm³.y−1 of H 2. • Economic analysis of hydrogen production equal to US$ 0.303/kWh. [ABSTRACT FROM AUTHOR]

Infrastructure projects like roads and hydroelectric dams are meant to help achieve national economic development goals in Brazil and the Amazon. In the case of hydropower dams, they have a very specific goal: that of producing energy from water sources. Unfortunately, that objective is frequently associated with environmental and social damages that result from the construction of dams. In the Amazon these damages are more serious in terms of the impacts on biological and cultural diversity. The research for this paper is based on 5 years of study by an interdisciplinary team using survey and ethnographic methods, both qualitative and quantitative. This history is repeated frequently, and it becomes necessary to ask what types of changes would be necessary to hydropower projects to begin to have social and environmental positive results. This paper explores the causes of the problems posed by dams and suggests solutions in the process of approval, construction and operation of hydropower dams that could lead to better outcomes for the common good of society. [ABSTRACT FROM AUTHOR]

Large numbers of dams for hydroelectric power production are currently planned or under construction in many areas around the world. While positive and negative social and environmental impacts of dams are increasingly well understood, little is known about attitudes of the general public towards dams, even though benefits to wider society are often cited to legitimise their construction. In Brazil's Upper Paraguay River Basin, more than 100 mostly small-scale hydropower dams are planned or under construction in what can be considered a regional dam construction boom. Here we analyse public preferences for strategies to manage dam impacts in the area by investigating the value base that underpins such preferences, drawing on the recently proposed Value Landscapes Approach as our theoretical framework and data from a large representative household survey (N = 1067). We find that contrasting attitudes towards dams, expressed in preferences for economically or ecologically oriented water policies are informed by opposing underlying value landscapes, that is, groups of closely related fundamental, governance-related, and assigned (water) values. While such tensions between opposing values can never be fully eliminated, our research nevertheless gives insights to policy-makers seeking to minimise value conflict and to improve the political legitimacy of public decision-making on dam construction. Moreover, we find that a majority of members of the general public would prefer concentrating dam construction on some rivers while keeping others free-flowing, with direct implications for ecosystems and inland fisheries. This finding may guide policy-makers wishing to develop publicly supported water resources management strategies. [ABSTRACT FROM AUTHOR]

The vulnerability of electric potential generation from water resources has been evidenced due to uncertainties of climatic origin and energy planning. Changes in rainfall regimes are multifactorial phenomena difficult to model. Rainfall is the main natural way of restoring the reservoir levels of hydroelectric power plants. The reduction in rainfall levels may increase in the coming years, resulting in a probable change of the energy matrix configuration of the state of Minas Gerais (MG). This could reduce the share of renewable sources increasing dependence on the importance of energy from fossil fuels, which are the immediate primary sources of energy available. Prior examinations have portrayed the depletion of hydroelectricity in Brazil, or its macro-regions, however this work tries to supply a more focused look at the effects on the electricity and social sectors of the state of Minas Gerais. The study developed in this paper aims to investigate the hydrological potential alteration impacts and consequences on the energy matrix of the state, the greenhouse gas emissions and the social reflexes of these changes due to scenarios motivated by climate change. The investigation intends to show the importance of the water-energy-emissions nexus for energy planning and decision-making, in order to evaluate the best options for dealing with adverse and potentially destabilizing conditions. The results of the analyses show that while hydropower demand was 5.24 Mtoe in 2015, in 2030 the supply of hydropower will be 5.81 Mtoe and 4.72 Mtoe, for the conservative and severe scenarios, respectively. In addition, the effect of climate change may require an increase in the share of non-renewable sources in the energy matrix, which could increase CO 2 e emissions from 4.2% to 7.4% by 2030, compared to the levels in 2016. • Reduction in rainfall levels will change the energy matrix configuration of MG state. • Population growth will boost demand for energy. • It is shown the importance of the water-energy-emissions nexus for energy planning and decision-making. • The energy matrix may considerably increase the CO 2 e emissions by 2030, compared with 2016 levels in the MG state. [ABSTRACT FROM AUTHOR]

Recent major droughts in Brazil have given rise to discussions about water availability and security in relation to energy production. The relationship of the two resources, the water-energy nexus, is recognised as being of importance in literature and metrics for its estimation and understanding are sought after. One important aspect in understanding the water-energy nexus of hydroelectricity is estimating its water consumption and also its water footprint. In order to do this, this study uses a modified Penman-Monteith method to estimate evaporation from Brazil's reservoirs for the period 2010-2016 and subsequently calculates the water footprint of hydroelectricity reservoirs. The results show the evaporation variation in space and time in the reservoirs and the differences of water consumed per unit of energy in Brazil. The discussion provides insight as to how the results can be valuable for future management and planning purposes. [ABSTRACT FROM AUTHOR]

Protected areas (PAs) remain the dominant policy to protect biodiversity and ecosystem services but have been shown to have limited impact when development interests force them to locations with lower deforestation pressure. Far less known is that such interests also cause widespread tempering, reduction, or removal of protection [i.e., PA downgrading, downsizing, and degazettement (PADDD)]. We inform responses to PADDD by proposing and testing a bargaining explanation for PADDD risks and deforestation impacts. We examine recent degazettements for hydropower development and rural settlements in the state of Rondônia in the Brazilian Amazon. Results support two hypotheses: (i) ineffective PAs (i.e., those where internal deforestation was similar to nearby rates) were more likely to be degazetted and (ii) degazettement of ineffective PAs caused limited, if any, additional deforestation. We also report on cases in which ineffective portions were upgraded. Overall our results suggest that enhancing PAs' ecological impacts enhances their legal durability. [ABSTRACT FROM AUTHOR]

Economic expansion and related resource and infrastructure needs provoke an increase of socio-environmental conflicts worldwide, and methodologies for their comprehensive analysis and understanding are necessary. The present paper suggests a methodology for the analysis of socio-environmental conflicts on hydropower, developed from a case study on the São Luiz do Tapajós project in Brazil. On the basis of qualitative semi-structured interviews, a stakeholder definition and conflict analysis were carried out. The analysis shows that at least five different sub-conflicts, each one with its own characteristics, can be distinguished, and that negotiation on many of these conflicts is difficult. Confrontation processes are therefore likely to occur. The current strategy of conflict treatment falls short of the situation; instead solutions must be sought looking at the underlying conflict causes. A restructuring of the energy policy and the approach to traditional populations is a necessary precondition if robust and comprehensive solutions on the current socio-environmental conflicts on hydropower in the Amazon were to be found. [ABSTRACT FROM AUTHOR]

The present work introduces hydro-wind correlation maps of Brazil calculated with wind speed data from weather stations and the registered historical natural inflows. The building of hydro-wind correlation maps was based on Voronoi cells, associated with values of correlation coefficients between seasonally averaged wind speeds and stream flows. We carried out four different correlation analyses. From the computed hydrologic correlation, we determined the most representative hydropower plants for each Brazilian basin. The wind correlation analysis confirmed the high similarity of the wind regimes throughout the country, but showed that the space variability is higher than the time variability. Local hydro-wind correlation analysis refers to the correlation between a basin's representative stream flow and the weather stations inside the same basin. The non-local analysis involved the correlation for each different stream flow regime with wind speed data from all the weather stations. Hydro-wind correlation maps are quantitative and more intuitive than previous analyses of wind and hydropower complementarity. By their use, it is possible to discern different behaviors for hydro-wind correlation throughout the Brazilian territory, either confirming previous results or identifying new features. Two examples show that hydro-wind correlation maps can be useful for operation and the expansion strategies. [ABSTRACT FROM AUTHOR]

Two Brazilian hydropower plants (Jupiá and Porto Primavera) located in the same watershed were explored in terms of the global resources needed to support these enterprises using a donor-side approach. Emergy theory and methods although commonly used by environmental scientists, may seem difficult to interpret for policy and decision-makers. Because of this, the possibility of transforming emergy flows and indices into money and area measures is explored in the present paper. Both hydropower plants deliver the same power and rely on practically the same infrastructure but involve very different flooded areas. Indirect areas calculated in terms of emergy show the different spatial distribution of resources. Some realistic alternatives for development were explored from both environmental and economic perspectives by using the emergy investment ratio and taking into account the matching between the enterprises emergy flows and the regional ones. [ABSTRACT FROM AUTHOR]

Copyright of Ambiente & Sociedade is the property of Nepam Unicamp 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.)

During atypical droughts, power systems with a heavy reliance on hydropower risk increased greenhouse gas emissions if they are balanced with fossil-fired generation. This work investigates the role of offshore wind energy in reducing the vulnerability of power systems dependent on such hydrological patterns, thereby eliminating this emission increase, using Brazil as a case study. Offshore wind potential and its complementarity with hydro resources are addressed by considering bias-corrected reanalysis data. Then, a cost-minimizing model is built to analyze the effect of integrating wind farms (considering bottom-fixed and floating structures and distance to shore) into the existing power system in Brazil. Applying a lower, median, and upper bias correction factor, potentials are reduced by 8%–44% compared to uncorrected data. Irrespective of systematic bias, the findings indicate a high complementarity between Northeastern wind regimes and most hydropower basins. The share of offshore wind energy grows in scenarios with reduced costs, but wind farms are part of the optimal system even with the current costs. With increasing wind power capacity, dynamic dispatch changes, and natural gas no longer plays a role in the dry season as it currently does, but only in the rainy season on a significantly reduced scale. Existing reservoirs support the integration of offshore wind farms into highly renewable scenarios, but they are insufficient in a complete fossil fuel phaseout, where other electricity storage must be deployed to help balance the system. Yet, power systems in the scenarios with large wind capacity have less stored hydropower in the dry season than in the current system, while they store more in the rainy season, implying a reduced risk of empty reservoirs. The Brazilian power system with offshore wind farms can eliminate 54.4 Mton CO 2 e q / y e a r (97% of current power sector emissions) without additional electricity storage. • Offshore wind potential with bias-corrected reanalysis data in Brazil. • High complementarity between Northeastern wind regimes and most hydro basins. • Natural gas no longer essential in the dry season in systems with a high wind share. • The combination of wind and hydro storage leads to a lower risk of empty reservoirs. • Addition of offshore wind can eliminate 97% of current power sector emissions. [ABSTRACT FROM AUTHOR]

Brazil has a predominantly renewable origin electricity generation matrix, with hydro generation accounting for about 69% of the supply. This paper promotes hydropower projects in Brazil environmental licensing procedure critical assessment, with the aim of identifying and assessing possible solutions to enhance the process, especially through Strategic Environmental Assessment (SEA) application to hydroelectric generation expansion planning processes. It was concluded that impact assessment has led to significant environmental improvements, as it is capable of preventing, controlling and compensating significant – and very often irreversible – environmental impacts, especially through projects optimization and environmental programs that were not initially foreseen in the EIA inclusion. However, as has been expounded throughout this study, there are still several gaps and limitations in the current process, both in power generation expansion planning aspect and project environmental impact assessment aspect. SEA application in the planning phase could contribute to facilitate and simplify hydroelectric plants licensing. Many currently compulsory stages that are carried out after the request for a prior license, such as the consultation made to involved entities and the area environmental diagnosis could already be commenced in the planning phase. [ABSTRACT FROM AUTHOR]

This paper evaluates the impacts of multiple water uses on the operation of a system of existing reservoirs that originally were designed for hydropower generation. The research reported in this paper utilizes a nonlinear optimization model, developed to optimize hydropower production for a system of interconnected reservoirs. This model was modified to include water withdrawals for consumptive uses. The formulated multiobjective optimization problem is solved by employing the weighting method. The formulation considers water allocation policy for consumptive uses and individual hydropower plants. By parametrically varying the weighting coefficients, the tradeoff relationship (Pareto front) between hydropower generation and water demand for consumptive uses was traced out. The modified model is applied to the São Francisco River Basin in Brazil, where there are several hydropower plants in operation with a total installed capacity of 10.7 GW. The river basin is an important agricultural land that requires water supply for crop irrigation. The power generation loss as a result of increased water demand due to consumptive uses was evaluated. Water demand scenarios range from current estimated consumptive uses to the amount expected to be granted by the federal government in the future. It is concluded that these demands cannot fully be met in critical drought periods, and the proposed methodology can be helpful in leading to more equitable solutions among competing water users. [ABSTRACT FROM AUTHOR]

Brazil plans to build 43 'large' dams (>30 MW) in the Tapajós Basin, ten of which are priorities for completion by 2022. Impacts include flooding indigenous lands and conservation units. The Tapajós River and two tributaries (the Juruena and Teles Pires Rivers) are also the focus of plans for waterways to transport soybeans from Mato Grosso to ports on the Amazon River. Dams would allow barges to pass rapids and waterfalls. The waterway plans require dams in a continuous chain, including the Chacorão Dam that would flood 18 700 ha of the Munduruku Indigenous Land. Protections in Brazil's constitution and legislation and in international conventions are easily neutralized through application of 'security suspensions,' as has already occurred during licensing of several dams currently under construction in the Tapajós Basin. Few are aware of 'security suspensions,' resulting in little impetus to change these laws. [ABSTRACT FROM AUTHOR]

Copyright of Brazilian Journal of Biology is the property of Instituto Internacional de Ecologia 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.)

Renewable energy has been encouraged to address climate change and promote sustainable development, leading to structural changes in the national energy matrices. Brazil is reaching a 50/50 renewable/non-renewable energy mix. However, the wide variability in emissions intensity among renewable sources raises questions about the effectiveness of structural changes for SDGs. The present study aims to identify typological profiles (TPs) of structural changes in sectoral energy and carbon footprint and their contributions to sustainable development. From an ecological input-output model, we calculated the sectoral energy and carbon footprint for 2000, 2005, 2010, and 2015. The method adds novelty by creating typologies of structural changes confronting renewable vs. non-renewable and mainly renewable vs. renewable. Four TPs of structural change were found. TP-I and TP-II tended to increase the relative share of renewables in their energy footprint, opposing TP-III and TP-IV. A controversy emerged contrasting TP-I and TP-II since both increased renewable consumption. TP-I decreased the renewable emissions while TP-II increased them. The explanation lies in the energy sources' emissions intensity. While TP-I sectors tended to increase the consumption of renewable energies with low intensity of emissions, such as electricity, TP-II sectors increased the consumption of renewables whose gross emissions intensity could be even higher than non-renewables. Therefore, the simple substitution of non-renewable for renewable sources may not be enough. Pursuing the long-term sustainable structural changes need to be planned based on renewable sources with the lowest net emission intensity and highest renewability. [Display omitted] • Replacing non-renewables with renewables may not be enough to achieve the SDGs. • Typological profiles (TPs) of structural changes may indicate the most effective strategies. • Effective pro-SDGs strategies move sectors from TP-IV, TP-III, and TP-II to TP-I. • Renewables with the lowest net emissions intensity and highest renewability are preferable. • Being renewable is not enough when the emission intensity is higher than non-renewables. [ABSTRACT FROM AUTHOR]

The article focuses on the impact of building hydroelectric power stations in Brazil on people living near a river, particularly the reconstruction of their identities after the relocation. Topics discussed include the philosophical side of the concept of identity including definitions from Habermas and Castells, the impact of forced displacement among riverside dwellers and the importance of the quality of new land in restructuring the identity among former riverside dwellers.

The changes in the fish assemblage of the Capivara Reservoir, Brazil, were assessed over a 20 year period. Of 50 native fishes present in the initial samples, 27 were no longer present in the final samples, but there had been an addition of 11 invasive fishes, suggesting the occurrence of substantial shifts in fish diversity and abundance. [ABSTRACT FROM AUTHOR]

• Hydropower projects are associated with a lack of participation by local population. • We evaluate participation mechanisms provided by dam builders in Brazil. • Negative perceptions before dam construction had little association with participation. • Local population participation was rare, fleeting, and insufficient. Energy infrastructure projects have long been associated with a lack of participation by impacted, local populations—this history is evident in the case of hydropower projects in the Global South. Ever since the World Commission on Dams' Report (WCD 2000), there has been substantive evidence, and numerous recommendations, that have called on governments, financial agencies and construction companies to increase community engagement and participation in dam construction and in their governance thereafter. Further, community groups, activists, and scholars have long articulated the need for participatory governance in energy projects. In this analysis, we evaluate participation in institutionalized mechanisms provided by dam builders—such as public meetings and negotiations—in Brazil's Madeira hydroelectric complex. We evaluate how perceptions of positive and negative impacts, among other factors, predict engagement, estimating a series of logit models based on a social survey of 673 households carried out in 2019/20. Perceptions of negative and positive impacts of the dams before construction are related to participation in the meetings promoted by dam builders. Yet our results also imply that participation was rare, fleeting, and insufficient and points to the need to ensure community engagement and governance to ensure energy justice in future dam projects in Brazil and elsewhere. [ABSTRACT FROM AUTHOR]

Abstract: An overview of the availability and affordability of energy sources and generation potential in Brazil is given in the present manuscript. Most of the information given here up-to-now was only accessible to Portuguese speakers, such as found in governmental plans for the energy sector. Brazilian public strategy for the following years concentrates on the promotion of more efficient energy utilization in different sectors of the society and also on diversifying its energy matrix. A perspective of programs, projects and technologies available in the country is also given. It is known that the Brazilian energy matrix is largely dominated by hydroelectric power, which relies on a consolidated infrastructure. However, recently discovered pre-salt layer of oil and natural gas presents new technological and scientific challenges for the professionals in the sector. National development and solidification of technologies for harnessing energy from the abundantly available biomass is yet another challenging task for Brazil. This manuscript not only presents the current Brazilian energy scenario and perspectives but also intends to identify some opportunities for investment and research, especially in the areas of materials science and engineering. A vision for what is expected for the Brazilian energy matrix based on current governmental actions and future technology is given in this perspective, while maintaining a critical overview on how to achieve optimum results with a balanced economic and environmental approach. [Copyright &y& Elsevier]

The Belo Monte hydropower scheme on the River Xingu in Brazilian Amazonia symbolizes the persistent contradictions between industrial modernization and resource conservation in a fragile environment. For over 30 years, local populations have battled with the energy authorities, contesting the top-down planning approach regularly applied in Brazilian infrastructure expansion. Reconfigured over the past decade as ‘neo-developmentist’, the model complements neoliberalism and is based on a strong alliance between the state as financial backer and the private sector as executor of such major schemes as Belo Monte. Following her predecessors, President Dilma continues to employ authoritarian tactics with little apparent regard for dealing comprehensively with its anticipated severe economic, ecological and social impacts, and with minimal consultation of diverse local groups, especially poorer agricultural and indigenous populations. More transparent and democratic planning procedures are necessary for Belo Monte and similar schemes if Brazil’s environmental credentials are not to be seriously compromised. [ABSTRACT FROM AUTHOR]

If due diligence is not undertaken on the ambiguities prevailing in the Mahakali Treaty and Letters of Exchange of 1996, then Nepal may well end up in a 'no option trap' like Paraguay on her 14,000 MW Itaipu, a bi-national hydropower project with Brazil. Twenty-five years after the commissioning of Itaipu, Paraguay is still battling with Brazil on such elementary but vital issues like fair energy price, third party access, parity in project management, etc. Nepal could and should learn lessons from Paraguay's Itaipu experiences. While Itaipu is primarily a hydropower project, Pancheshwar encompasses wider multipurpose applications. This article, however, limits itself only to the hydropower component of the two projects. [ABSTRACT FROM AUTHOR]

Abstract: Representative Life-Cycle Inventories (LCIs) are essential for Life-Cycle Assessments (LCAs) quality and readiness. Because energy is such an important element of LCAs, appropriate LCIs on energy are crucial, and due to the prevalence of hydropower on Brazilian electricity mix, the frequently used LCIs are not representative of the Brazilian conditions. The present study developed a LCI of the Itaipu Hydropower Plant, the major hydropower plant in the world, responsible for producing 23.8% of Brazil''s electricity consumption. Focused on the capital investments to construct and operate the dam, the LCI was designed to serve as a database for the LCAs of Brazilian hydroelectricity production. The life-cycle boundaries encompass the construction and operation of the dam, as well as the life-cycles of the most important material and energy consumptions (cement, steel, copper, diesel oil, lubricant oil), as well as construction site operation, emissions from reservoir flooding, material and workers transportation, and earthworks. As a result, besides the presented inventory, it was possible to determine the following processes, and respective environmental burdens as the most important life-cycle hotspots: reservoir filling (CO2 and CH4 emission; land use); steel life-cycle (water and energy consumption; CO, particulates, SO x and NO x emissions); cement life-cycle (water and energy consumption; CO2 and particulate emissions); and operation of civil construction machines (diesel consumption; NO x emissions). Compared with another hydropower studies, the LCI showed magnitude adequacy, with better results than small hydropower, which reveals a scale economy for material and energy exchanges in the case of Itaipu Power Plant. [Copyright &y& Elsevier]

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]

The performance of a simple, spatially-lumped, rainfall–streamflow model is compared with that of a more complex, spatially-distributed model. In terms of two model-fit statistics it is shown that for two catchments in Brazil (about 30,000km2 and 34,000km2) with different flow regimes, the simpler catchment models, which are unit hydrograph-based and require only rainfall, streamflow and air temperature data for calibration, perform about as well as more complex catchment models that require additional information from satellite images and digitized maps of elevation, land-use and soils. Simple catchment models are applied in forecasting mode, using daily rainfall forecasts from a regional weather forecasting model. The value of the rainfall forecasts, relative to the case where rainfall is known, is assessed for both catchments. The results are discussed in the context of on-going work to compare different modelling approaches for many other Brazilian catchments, and to apply improved forecasting algorithms based on the simple modelling approach to the same, and other, catchments. [Copyright &y& Elsevier]

Hydroelectric dams represent major investments and major sources of environmental and social impacts. Powerful forces surround the decision-making process on public investments in the various options for the generation and conservation of electricity. Brazil’s proposed Belo Monte Dam (formerly Kararaô) and its upstream counterpart, the Altamira Dam (better known by its former name of Babaquara) are at the center of controversies on the decision-making process for major infrastructure projects in Amazonia. The Belo Monte Dam by itself would have a small reservoir area (440 km2) and large installed capacity (11, 181.3 MW), but the Altamira/Babaquara Dam that would regulate the flow of the Xingu River (thereby increasing power generation at Belo Monte) would flood a vast area (6140 km2). The great impact of dams provides a powerful reason for Brazil to reassess its current policies that allocate large amounts of energy in the country’s national grid to subsidized aluminum smelting for export. The case of Belo Monte and the five additional dams planned upstream (including the Altamira/Babaquara Dam) indicate the need for Brazil to reform its environmental assessment and licensing system to include the impacts of multiple interdependent projects. [ABSTRACT FROM AUTHOR]

The most robust methods to determine the capacity contribution from intermittent sources combine load curve, variable generation profile, and dispatchable generators' data to calculate any new inserted variable source's capacity value in the power system. However, these methods invariably adopt the premise that the system's dispatchable generators' capacity is constant. That is an unacceptable limitation when the energy mix has a large share of hydroelectric sources. Hydroelectric plants are dispatchable sources with variable maximum power output over time, varying mainly according to the reservoirs' level. This article develops a method that makes it possible to calculate the capacity value from renewable resources when the dispatchable generation units of an electric system have variable capacity. The authors apply the method to calculate the capacity value from solar and wind sources in Brazil as an exercise. By abandoning the hypothesis of constant dispatchable capacity, the developed approach is in principle extensible for other energy-limited resources, such as batteries and concentrating solar power (CSP). This can be a strategy to incorporate energy-limited capacity sources into the planning and operation models as reliable capacity sources. [ABSTRACT FROM AUTHOR]

With increasing electric demand and the continued underproduction of existing dams and the environmental and social concerns of traditional hydropower dam expansion in the Amazon region, alternative power sources are needed to meet future power needs. Recently, large-scale deployment of photovoltaic (PV) systems has gained more interest globally, mainly because of the improved technology and rapid price decrease. Although solar power in Brazil makes up a small percentage of its generation mix, large-scale deployment could potentially be one of the promising solutions for offsetting dams' underproduction. This work evaluates the benefits of adding floating PV (FPV) systems on system adequacy. FPV systems are integrated alongside existing dams to enhance the existing power sources and provide an alternative pathway to meet the increasing power demand without the need for more dams. System adequacy is evaluated with the current production of dams and the required capacities of FPV systems to compensate for the current underproduction of dams. Furthermore, the correlation between PV output and system load is evaluated, and the environmental and social concerns associated with dam expansion in the Amazon basin are briefly discussed. The results indicate that the investment toward installing FPV systems on the dams' reservoirs leads to a significant improvement to the overall system reliability, minimize load curtailment, and could potentially add more flexibility to the operator to dispatch power generated by hydropower plants during peak demands. • Evaluate the potential contribution of floating PV systems to the Brazilian power grid. • Evaluate the contribution of large-scale deployment of FPV systems to the system adequacy. • The environmental and social concerns associated with dam expansion in the. [ABSTRACT FROM AUTHOR]

The 21st century has witnessed a resurgence of hydropower projects across the globe, with the energy source an integral part of contemporary sustainable energy transitions. Yet, the environmentalist credentials of hydropower remain contested by anti-dam movements. This paper details the cases of the Belo Monte and São Luiz do Tapajós dams in the Brazilian Amazon to explore how the development, submission and acceptance of an Environmental Impact Assessment provides a key site in the contestation of hydroelectric projects. Whilst the provision of this document – and the wider environmental licensing process – represents a key component in the asserted 'green-ness' of hydropower, opposition groups extend the scope of analysis to include indirect and cumulative impacts that remain understudied in official assessments. This paper analyses interviews and questionnaires with and documents provided by national and international civil society organisations to trace this process of challenge and critique. It details how civil society actors forward alternative assessments of the impacts of the projects studied, uncovering and illuminating overlooked and understudied externalities of hydropower in the Brazilian Amazon. An analysis of this process not only demonstrates that the 'green' credentials of hydropower remain far from assured but also highlights how anti-dam actors advance new 'sustainabilities' to discredit the terrain upon which such credentials are set. [ABSTRACT FROM AUTHOR]

Summary: The positive impact of the complementarity between renewable generation sources has been presented in several studies, but this concept has been neglected in many studies of expansion planning. This paper presents a new approach to introduce the complementarity between renewable energy resources and regions into the expansion planning for 100% renewable energy systems. A novel objective function is proposed to optimize the electricity mix and the water flow of hydropower reservoirs, considering the daily and yearly variations. A case study is presented with the objective of assessing the optimum mix (for the complementarity perspective) between solar, wind, hydro, and biomass power to ensure the expected monthly and hourly energy demand for Brazil in 2050. In the Brazilian case, when the complementarity between regions was considered, it was possible to ensure the electricity demand increase without new large reservoirs and with a high contribution from all renewable generation sources. A mix to ensure the daily and annual demand in 2050, which promotes the best complementarity, is presented, resulting in a share of 27%, 16%, 34%, and 23% for photovoltaic, wind, hydro, and biomass power, respectively. [ABSTRACT FROM AUTHOR]

Water management is important for delivering water for different users and uses. Reservoirs are built to overcome the stochastic nature of river flows and to increase the reliability of water supply. Reservoir operation affects the ecology of downstream river sections, and there has been a discussion of a more ecologically oriented flow regime, although ecosystems of reservoirs themselves are rarely taken into account. For reservoirs, it is important to identify multiple impacts and trade‐offs of different management options. This information can be used in a multidisciplinary and multiparticipatory decision‐making process to assess the management options. This study develops, applies, and discusses reservoir operation options for the São Francisco River basin (Brazil): (a) Reference; (b) Environmental discharge; (c) Reduced daily water‐level variation; and (d) Reduced annual water‐level variation. In the simulation study, the operation option with reduced daily water‐level variation in reservoirs turned out to be the most flexible, guaranteeing hydropower generation and water supply in the dry season, while considering the ecology of the reservoirs and rivers. The simulations are exemplary for decision makers, requiring further assessment after agreeing on priority setting. [ABSTRACT FROM AUTHOR]

Fish reproductive guilds were used to evaluate the responses of species with different reproductive strategies during two different periods of post-dam construction. The data used for the comparisons were collected in the upper Paraná River floodplain (Brazil), downstream of the Porto Primavera dam, 2 and 10 years after impoundment. The abundance (catch per unit effort, CPUE), species richness, evenness and structure of communities, all within reproductive guilds, were used to test the hypothesis that these metrics vary spatially and temporally. The influence of damming on species structure and the diversity of fish reproductive guilds varied spatiotemporally, and species with opportunistic reproductive strategies tended to be less affected. Conversely, long-distance migratory species responded more markedly to spatiotemporal variations, indicating that the ecosystem dynamics exert greater effects on populations of these species. Thus, the effects of a dam, even if attenuated, may extend over several years, especially downstream. This finding emphasizes the importance of maintaining large undammed tributaries downstream of reservoirs., (© 2014 The Fisheries Society of the British Isles.)