Navegando por Assunto "Energia solar"

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Acesso aberto (Open Access)
Análise da viabilidade técnico-econômica da geração de energia solar fotovoltaica em unidades de confinamento bovino com sombreamento artificial
(Universidade Federal do Pará, 2020-05-28) MORAES, Emerson Ricardo de; MOURÃO, Raphael de Castro; http://lattes.cnpq.br/6637481796428177; ISHIHARA, Júnior Hiroyuki; http://lattes.cnpq.br/3498874642887006; https://orcid.org/0000-0002-0081-7913
The increase in worldwide population caused a rising search by food, both origins, vegetable and animal. Due the decrease in rural areas to destined for livestock activities, as a result to greater use of areas for agriculture, there are an intensification in cattle farming, the aim to use a smallest area of property for a large quantities of animals, at same time, associated the animal welfare and its thermal comfort, and provide improvement in production system. This population increase also implicate in higher demand for electric energy sources, due to the improvement of living standards and advances technologic. The objective this work was to analyze the technical and economic viability of the generation of solar photovoltaic energy, in line the livestock activity, using the shading sheds coverage in beef cattle feedlot. A bibliographic study was carried out on the animal yield of the Nellore breed, in confinement in a tropical climate, in the situation of total exposure to the sun or with the use of shady sheds. Three scenarios were created for the analysis of animal welfare, the animal being confined in the open, confinement with the use of shading sheds and confinement with the generation of solar photovoltaic energy on the roof of its shading shed. Two alternative meteorological stations were made to collected the samples of local climatic variables, and calculate the indices of thermal comfort and animal well-being, and to identify the possible beef cattle yield at the study site. Budgets for items and services were made for the execution of projects for containment pens, roof sheds and distributed generation of photovoltaic solar energy, for further analysis of the technical and economic feasibility of the projects. The results showed greater economic viability, with greater profitability and shorter return on investment, for the treatments of confinement pens in the open, which present, for the population of 200, 600 and 1000 animals, an IRR of 75.86%, 86.71% and 89.88%, PI of 4.68, 5.34 and 5.53 and discounted payback of 1.49, 1.29 and 1.24 years, respectively, while for the construction of the entire structure together with the generation of solar photovoltaic energy, it was obtained, in the same order, IRR of 22.30%, 14.09% and 14.62%, PI of 1.58, 1.18 and 1.21 and discounted payback of 5.17, 7.71 and 7.48 years. Although the economic feasibility was not the best, treatments with a photovoltaic energy generation system connected to the distribution network, when built together with the structures of confinement and shed pens, provide greater comfort to the animals and enable the generation of energy renewable. The result of the photovoltaic installation was more economically viable, when mounted on shed structures already existing in confinement systems for 200 animals, which presented an IRR of 23.72%, PI of 1.65 and a discounted payback of 4.88 years. It is concluded that the most viable design option for the creation of animals in feedlot, is the open model for the largest number of animals, while for the generation of energy, it is the system connected to the low voltage network mounted on shed structures already in feedlot systems for 200 animals, without the need for demand contracts, containing 200 photovoltaic panels.
Acesso aberto (Open Access)
Análise de desempenho de um sistema fotovoltaico domiciliar de pequeno porte operando com diferentes equipamentos
(Universidade Federal do Pará, 2015-02-23) MAIA, Keila Cristina dos Santos; PINHO, João Tavares; http://lattes.cnpq.br/0847897516772421; MACÊDO, Wilson Negrão; http://lattes.cnpq.br/3386249951714088
This work presents the operational analysis of the operation of a 180 Wp solar home system designed to supply small loads. The solar home system is installed at the laboratory testing area of the “Grupo de Estudos e Desenvolvimento de Alternativas Energéticas” (GEDAE), in order to simulate its operation as electricity supply for a typical riparian residence of the Amazon. For this, it was simulated the use of loads that are frequently used in these homes (TV and lamps) at predefined times. Besides the description of the system components, the mechanisms for monitor its operation and to analyze the data obtained about the behavior of the system operating with different technologies of inverters (sine, square and modified square output waveforms), charge controllers and deep cycle batteries are also presented.
Acesso aberto (Open Access)
Desempenhos térmico e energético de uma edificação na região amazônica brasileira
(Universidade Federal do Pará, 2018-09-06) AGUILAR, Heliana Maria Ceballos; PINHO, João Tavares; http://lattes.cnpq.br/0847897516772421
This work presents an innovative proposal of integration of several strategies to reduce energy consumption, where the impact of each one of them is evaluated individually, and all together, in the thermal, energetic and economic performance of a building located in the Brazilian Amazon Region. High temperature and humidity characterize this region climatically, where achieving adequate comfort conditions implies a high demand for energy for air conditioning systems. Different Energy Conservation Measures are evatuated in order to achieve a better use of daylighting; and to reduce thermal loads for cooling, with the installation of a thermal insulation material in the eastern and western walls, and a thermal insulation and air chamber in the roof, which are the external surfaces that receive higher solar radiation in the building. Additionally, various photovoltaic generation systems are considered, one of which is integrated as an architectural element and another adapted on the roof of the building. In the building, two types of analysis are conducted: dynamic and static. For the dynamic analysis, the EnergyPlus software is used to know its thermal and energy consumption performances, analyzed for the entire year and for the design day, and the Daysim/Radiance software to know the autonomy of daylighting attained, using data measured with an on-site meteorological station. Concerning the static analysis, the level of energy efficiency is evaluated by the prescriptive method according to the current national regulations. Subsequently, the same building is simulated for the nine capital cities of the states of the Legal Brazilian Amazon Region, with the aim of knowing its energetic performance and the economic feasibility depending on the climatic characteristics and electrical energy tariffs of each city. With the assessments performed, it is determined that the ECM have a direct and significant influence on the reduction of the thermal load for cooling, through the reduction of radiation effects, the shading in the eaves and the reduction of the transmittance of the surfaces treated. The possibility of maximizing the daylight in internal spaces, to improve the comfort of the users is also verified, allowing better performance and energy savings with artificial lighting. In terms of energy consumption and economic feasibility, the ECM achieve an annual energy savings of 52 % in the building taken as a case study, and the solutions adopted show a good return on financial investment, and are also suitable for energy saving and economically feasible in regions with similar climatic characteristics.
Acesso aberto (Open Access)
Lead poisoning in cattle and chickens in the state of Pará, Brazil
(2014-11) BARBOSA NETO, José Diomedes; BOMJARDIM, Henrique dos Anjos; CAMPOS, Karinny Ferreira; DUARTE, Marcos Dutra; BEZERRA JÚNIOR, Pedro Soares; GAVA, Aldo; SALVARANI, Felipe Masiero; OLIVEIRA, Carlos Magno Chaves
The present study describes the occurrence of lead poisoning in cattle and chickens in Pará, Brazil. In a lot composed of 80 calves from a dairy herd, 10 animals became sick and nine died, but one animal recovered after being removed from the paddock. Upon inspection of this paddock, the presence of truck batteries used to store energy captured by solar panels was found. The clinical signs observed in calves included difficult breathing, nasal discharge, excessive salivation, corneal opacity, pushing of the head against objects and recumbency. The chickens had decreased oviposition and produced eggs with thin or malformed shells. The necropsy findings of the cattle, as well as the histopathological changes observed, were of little significance except for one animal that showed mild astrocytosis histopathology in the cerebral cortex. In one of the chickens, renal histopathology showed mild multifocal acute tubular necrosis. The mean lead concentrations in the livers and kidneys of the cattle were 93.91mg/kg and 209.76mg/kg, respectively, and the mean concentration detected in chicken livers was 105.02mg/kg. It was concluded that the source of lead poisoning in these calves and chickens were the truck battery plates, which were within reach of the animals.
Acesso aberto (Open Access)
Otimização de nanoantenas plasmônicas para células solares orgânicas
(Universidade Federal do Pará, 2016-01-18) SILVA JÚNIOR, Marcelino Lopes Corrêa da; DMITRIEV, Victor Alexandrovich; http://lattes.cnpq.br/0684541646225359; COSTA, Karlo Queiroz da; http://lattes.cnpq.br/7932708321834647
This work shows a theoretical nanoantennas study about organic solar cells of thin films, occasioning the increase in the efficiency of light absorption. The unitary organic solar cell formed by a reflector silver block, an active layer formed by the semiconductor P3HT:PCBM and a nanoantenna, also made of silver. The numerical analysis of the device is made through the Finite Element Method; the materials are analysed from the relative permittivity. Firstly, we executed the validation of the nanostructure through the numerical method. Then, we apply the geometric optimization process in the other nanoantenna models. This optimization process was based on nanoantennas geometrical parameters preserving its superficial area. Since were considered four new models of nanoantennas with different geometrical parameters, which means, conical nanoantennas, root cone, and exponential root cone 1 and 2. It was observed, from the efficiency of integrated absorption for different incidence angles and light polarization, current density and plasmonic decay that the nanoantennas, the root cone and the exponential cone 2, gave better performance compared to the other models.