Gamaro P.E.,Itaipu Binacional |
Maldonado L.H.,Itaipu Binacional |
Castro J.L.,Itaipu Binacional |
Bastolla V.P.,United International University Dhanmondi
River Sedimentation - Proceedings of the 13th International Symposium on River Sedimentation, ISRS 2016 | Year: 2017
The estimation of sand transport in large rivers is an important parcel of the total load. Moreover, because of the measurement difficulties and the traditional sampling techniques are prone to large errors the bed load is calculated as a percentage of the suspension sediment load. To compare the validation of this indirectly method, the technique of dune displacement was then used to estimate bed load, starting to monitor Guaira Braço Direito Gauge Stations, Paraná River. This procedure allowed an understanding the modifications of bed river and dune bed form. This paper presents results of a year monitoring every 30 to 45 days for years 2013/2014 and compares to random bed load measurements using the simplifying dunes tracking results and the same method computing the dune shape form. The bed load estimated computing the dune shape coefficient was 374,000 ton.year−1 and adopting a triangular shape resulted a negative deviation of 11%. Besides that, was possible to note the modification of the dunes displacement and dunes shape coefficient with discharge variations. © 2017 Taylor & Francis Group, London.
Kohn A.,Instituto Oswaldo Cruz |
Moravec F.,Academy of Sciences of the Czech Republic |
Cohen S.C.,Instituto Oswaldo Cruz |
Canzi C.,Itaipu Binacional |
And 2 more authors.
Check List | Year: 2011
This study presents results from several expeditions in 1985, 1991-1995 and 2003 to the Medium Paraná River in the section that begins below the Itaipu Dam and ends at the trinational border of Brazil, Argentina and Paraguay, in the lotic and lentic zones of the reservoir of the Hydroelectric Power Station of "Itaipu Binacional" (localities Foz do Iguaçu, Santa Helena and Guaira). Ninety-eight species of freshwater fishes belonging to 22 families were examined for helminths. A host-parasite list based on Acanthocephala, Cestoda, Digenea, Monogenea and Nematoda collected from the region in question is provided. New host records are presented for Digenea and Nematoda. The Monogenea and Acanthocephala are being studied and will be published in a later paper, but are referred in the host-parasite list, in order to demonstrate the parasitism in the fishes of the reservoir. The results are compared with those presented by other authors from the Upper Paraná River. © 2011 Check List and Authors.
Makrakis S.,University of Toledo |
Miranda L.E.,U.S. Geological Survey |
Gomes L.C.,State University of Maringá |
Makrakis M.C.,University of Toledo |
Junior H.M.F.,Itaipu Binacional
River Research and Applications | Year: 2011
The Piracema Canal is a complex 10-km fish pass system that climbs 120m to connect the Paraná River to the Itaipu Reservoir along the Brazil-Paraguay border. The canal was constructed to allow migratory fishes to reach suitable habitats for reproduction and feeding in tributaries upstream from the reservoir. The Piracema Canal attracted 17 of the 19 long-distance migratory species that have been recorded in the Paraná River Basin and Paraguay-Paraná Basin. However, the incidence of migratory fish decreased from downstream to upstream, with the pattern of decrease depending on species. Overall, 0.5% of the migratory fish that entered the Piracema Canal and segment 1, eventually were able to reach segment 5 and potentially Itaipu Reservoir. Ascension rate was examined relative to various physical attributes of canal segments; maximum water velocity emerged as the most influential variable affecting fish passage. Water velocity may be manipulated by controlling water discharge, and by re-engineering critical sections of the canal. Because the Itaipu Reservoir flooded a set of falls that separated two distinct biogeographical regions, facilitating fish movements through the Piracema Canal into the Itaipu Reservoir presents a management dilemma that requires deliberation in the context of the fish assemblages rather than on selected migratory species. © 2010 John Wiley & Sons, Ltd.
Makrakis M.C.,West Parana State University |
Miranda L.E.,U.S. Geological Survey |
Makrakis S.,West Parana State University |
Fontes Junior H.M.,Itaipu Binacional |
And 3 more authors.
Journal of Fish Biology | Year: 2012
Migratory behaviour of selected fish species is described in the Paraná River, Brazil-Argentina-Paraguay, to search for patterns relevant to tropical regulated river systems. In a 10 year mark-recapture study, spanning a 1425 km section of the river, 32 867 fishes composed of 18 species were released and 1083 fishes were recaptured. The fishes recaptured were at liberty an average 166 days (maximum 1548 days) and travelled an average 35 km (range 0-625 km). Cluster analysis applied to variables descriptive of movement behaviour identified four general movement patterns. Cluster 1 included species that moved long distances (mean 164 km) upstream (54%) and downstream (40%) the mainstem river and showed high incidence (27%) of passage through dams; cluster 2 also exhibited high rate of movement along the mainstem (49% upstream, 13% downstream), but moved small distances (mean 10 km); cluster 3 included the most fishes moving laterally into tributaries (45%) or not moving at all (25%), but little downstream movement (8%); fishes in cluster 4 exhibited little upstream movement (13%) and farthest downstream movements (mean 41 km). Whereas species could be numerically clustered with statistical models, a species ordination showed ample spread, suggesting that species exhibit diverse movement patterns that cannot be easily classified into just a few classes. The cluster and ordination procedures also showed that adults and juveniles of the same species exhibit similar movement patterns. Conventional concepts about Neotropical migratory fishes portray them as travelling long distances upstream. The present results broaden these concepts suggesting that migratory movements are more diverse, could be long, short or at times absent, upriver, downriver or lateral, and the diversity of movements can vary within and among species. The intense lateral migrations exhibited by a diversity of species, especially to and from large tributaries (above reservoirs) and reservoir tributaries, illustrate the importance of these habitats for the fish species life cycle. Considering that the Paraná River is highly impounded, special attention should be given to the few remaining low-impact habitats as they continue to be targets of hydropower development that will probably intensify the effects on migratory fish stocks. © 2012 The Authors. Journal of Fish Biology © 2012 The Fisheries Society of the British Isles.
Leite Da Silva A.M.,Pontifical Catholic University of Rio de Janeiro |
De Carvalho Costa J.G.,Federal University of Itajubá |
Machado K.G.,Federal University of Itajubá |
De Souza L.L.,Electrical Company of Minas Gerais |
Gonzalez-Fernandez R.A.,ITAIPU Binacional
IEEE Transactions on Power Systems | Year: 2015
This paper proposes a new probabilistic method based on chronological Monte Carlo simulation for computing optimal distribution substation spare transformers. The method allows the representation of events such as aging process, load growth, and other conditions not supported by traditional methods based on Poisson and Markov processes. The lifetimes of the transformers are represented by discrete probability distributions, determined by an algorithm that combines the aging of the insulating material, estimated by Arrhenius theory, with the loss of life caused by short-circuits, lightning and switching surges. To illustrate the importance of sizing the inventory based on reliability indices and costs, the proposed method is applied to a group of substations with 177 transformers of 138-13.8 kV, with power rating of 25 MVA. Finally, the proposed methodology is used in combination with a metaheuristic algorithm for determining the optimal timing strategy for composing of the stock of spare transformers over a pre-established planning horizon. © 1969-2012 IEEE.
Cunha D.G.F.,University of Sao Paulo |
Benassi S.F.,Itaipu Binacional |
de Falco P.B.,University of Sao Paulo |
do Carmo Calijuri M.,University of Sao Paulo
Environmental Management | Year: 2016
Artificial reservoirs have been used for drinking water supply, other human activities, flood control and pollution abatement worldwide, providing overall benefits to downstream water quality. Most reservoirs in Brazil were built during the 1970s, but their long-term patterns of trophic status, water chemistry, and nutrient removal are still not very well characterized. We aimed to evaluate water quality time series (1985–2010) data from the riverine and lacustrine zones of the transboundary Itaipu Reservoir (Brazil/Paraguay). We examined total phosphorus and nitrogen, chlorophyll a concentrations, water transparency, and phytoplankton density to look for spatial and temporal trends and correlations with trophic state evolution and nutrient retention. There was significant temporal and spatial water quality variation (P < 0.01, ANCOVA). The results indicated that the water quality and structure of the reservoir were mainly affected by one internal force (hydrodynamics) and one external force (upstream cascading reservoirs). Nutrient and chlorophyll a concentrations tended to be lower in the lacustrine zone and decreased over the 25-year timeframe. Reservoir operational features seemed to be limiting primary production and phytoplankton development, which exhibited a maximum density of 6050 org/mL. The relatively small nutrient concentrations in the riverine zone were probably related to the effect of the cascade reservoirs upstream of Itaipu and led to relatively low removal percentages. Our study suggested that water quality problems may be more pronounced immediately after the filling phase of the artificial reservoirs, associated with the initial decomposition of drowned vegetation at the very beginning of reservoir operation. © 2015, Springer Science+Business Media New York.
PubMed | Itaipu Binacional and University of Sao Paulo
Type: Journal Article | Journal: Environmental management | Year: 2016
Artificial reservoirs have been used for drinking water supply, other human activities, flood control and pollution abatement worldwide, providing overall benefits to downstream water quality. Most reservoirs in Brazil were built during the 1970s, but their long-term patterns of trophic status, water chemistry, and nutrient removal are still not very well characterized. We aimed to evaluate water quality time series (1985-2010) data from the riverine and lacustrine zones of the transboundary Itaipu Reservoir (Brazil/Paraguay). We examined total phosphorus and nitrogen, chlorophyll a concentrations, water transparency, and phytoplankton density to look for spatial and temporal trends and correlations with trophic state evolution and nutrient retention. There was significant temporal and spatial water quality variation (P<0.01, ANCOVA). The results indicated that the water quality and structure of the reservoir were mainly affected by one internal force (hydrodynamics) and one external force (upstream cascading reservoirs). Nutrient and chlorophyll a concentrations tended to be lower in the lacustrine zone and decreased over the 25-year timeframe. Reservoir operational features seemed to be limiting primary production and phytoplankton development, which exhibited a maximum density of 6050 org/mL. The relatively small nutrient concentrations in the riverine zone were probably related to the effect of the cascade reservoirs upstream of Itaipu and led to relatively low removal percentages. Our study suggested that water quality problems may be more pronounced immediately after the filling phase of the artificial reservoirs, associated with the initial decomposition of drowned vegetation at the very beginning of reservoir operation.
Rivarolo M.,University of Genoa |
Bogarin J.,Itaipu Binacional |
Magistri L.,University of Genoa |
Massardo A.F.,University of Genoa
International Journal of Hydrogen Energy | Year: 2012
In this paper hydrogen generation and storage systems optimization, related to a very large size hydraulic plant (Itaipu, 14 GW) in South America, is investigated using an original multilevel thermo-economic optimization approach developed by the Authors. Hydrogen is produced by water electrolysis employing time-dependent hydraulic energy related to the water which is not normally used by the plant, named "spilled water". From a thermo-economic point of view, the two main aspects of the study are the optimal definition of the plant size and the whole system management. Both of them are strongly influenced by (i) spilled water energy variability related to its time-dependent distribution during the whole year, (ii) time-dependent electricity demand of Paraguay and Brazil (the owners of the Itaipu plant) electrical grids, and (iii) the hydrogen demand profile. The system analyzed here consists of a very large size hydrogen generation plant (hundreds of MW) based on pressurised water electrolysers fed with the so called "spilled water electricity", the related H 2 storage, and the H 2 demand profile for Paraguay transport sector utilization. Since H 2 plant optimal size is strongly correlated to optimal management and vice-versa, in this paper two hierarchical levels have been considered hour by hour on a complete year time period, in order to minimize capital and variable costs. This time period analysis is necessary to properly take into account spilled energy variability to find out H 2 production system optimal size, optimal storage solution and best economical results. For the optimal storage size, two different solutions have been carefully investigated: (i) classical long time H 2 physical storage using pressurised tanks at 200 bar; (ii) hybrid one using reduced size physical storage (one day time demand) where the energy to feed electrolysers is taken from electrical grid when spilled water energy is not available [Rivarolo M, Bogarin J, Magistri L, Massardo AF. Hydrogen generation with large size renewable plants: the Itaipu 14 GW hydraulic plant case. In: 3rd international conference of applied energy (ICAE), 16-18 May 2011, Perugia; 2011.]. For both the two solutions, time-dependent results are presented and discussed with particular emphasis to economic aspects, system size, capital costs and related investments. It is worthy to note that the results reported here for this particular H 2 large size plant case represent a general methodology, since it is applicable to different size, primary renewable energy, plant location, and different H 2 utilization. © 2011, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.
Da Silva J.R.,ITAIPU BINACIONAL |
Bastos J.P.A.,Federal University of Santa Catarina
IEEE Transactions on Magnetics | Year: 2015
The efficiency of the finite element method (FEM) for the design and improvement of electromagnetic devices has already been established several decades ago. This powerful tool is also used for the improvement of power transformer designs whose complexity can be handled by the FEM. This paper addresses the influence of simplifications to be made on the geometries of power transformers for the performance of electromagnetic and thermodynamic simulations to diminish the computational time and to obtain the electric and magnetic fields, temperatures, and heat flow in the interior of the transformer. © 2015 IEEE.
Silveira E.F.,ITAIPU BINACIONAL |
De Oliveira T.F.,University of Brasilia |
Junior A.C.P.B.,University of Brasilia
Energy Procedia | Year: 2015
This work presents different hybrid energy scenarios for local electricity supply in Fernando de Noronha Archipelago-Brazil. One considers different generating solutions for energy systems ranging from totally fossil fuel based to all renewable sources. The scenarios are constructed using local database measurements; real equipment data and a micro-grid hybrid system modeling (using HOMER Software). The modeling and simulation consider the evaluation of different sizes and quantities of energetic components and the variation in the availability of the natural resources (wind and solar). A Hybrid solution with 67% participation of renewable energy was found feasible for the island and the impact of changing the local vehicle fleet from combustion to electric traction was also addressed. © 2015 The Authors. Published by Elsevier Ltd.