Projeto elétrico básico de uma subestação industrial típica na classe 15 kV

The electrical substations have the goal to transmit, distribute and change the characteristics of electrical energy transmission networks of dealers to the end user with a high rate of reliability and continuously. For this it’s necessary to accomplish a gathering of datas from the local dealers where will be installed the substation to make a good electric project. This work has the objective to gather all the contents relatives to electric project of substation that are scattered in the literature, in order to organize and develop a basic guide that presents a methodology to dimension electrical equipments that belong to an industrial substation at 15 kV. In addition to elaborate a basic guide, this work aids to specify electrical equipments installed in the substation, bringing information and comparisons to know and determinate the kind of equipments that will be used, in a correct and coherent way with the national and international rules. Ultimately, after determined, got and specified all the equipments that belongs to an industrial substation, the work mention in global manner how to calculate the dimension of substation physical arrangement, determining all the least and required dimensions of each cubicle

Anteprojeto de um sistema digital de proteção e controle aplicado em uma subestação elétrica industrial

With the growth of the demand on electric energy in the last decades, the urban distribution and transmission systems have experienced a bigger necessity to improve on the substations, the automation procedures and techniques on the operation maneuvers of such systems, in a sense that better attends the quality levels, availability, continuity and operational reliability. In this way, the objective of the present paper is to perform a study of protection and control on an electrical industrial system involving the procedures of digitizing and maneuvers automatism utilizing operational techniques and other pertinent information used in a typical high-voltage Industrial Electrical System. Analysis were made on short-circuits to specify the main components of the 138 [kV] substation, in addition, there were used digital MiCOM relays to make the protection of the present elements. With that, a program was developed to allow the user to monitor the condition of circuit-breakers through a supervision screen being able to simulate some kinds of faults, as well as observing the characteristics of each device. This way, the importance of having a fast and reliable system that ensures the equipment’s protection and the industrial process continuity due to faults on the electrical system is noticeable. It’s important to highlight that all this digitizing was mainly favored by the development of digital technology on the last years, mainly on microelectronics, also with the appearance of supervision gadgets allowing the development of complex systems in supervision and electric energy control

Coexistence between Nearctic-Neotropical migratory shorebirds and humans on urban beaches of the Southern Hemisphere: a current conservation challenge in developing countries

The arrival of migratory shorebirds on beaches in urban communities in developing countries is a current challenge for the protection of these migrant birds. Nearctic-Neotropical migrants rely on roosting and feeding sites during their stopover on wintering sites in the Southern Hemisphere to acquire sufficient energy to complete their migratory cycles. On the other hand, cities in the Southern Hemisphere are growing rapidly, which results in increasing competition for space between humans and birds, such as for use in beach habitats. In the present study, I analyze the probability for occurrence for Nearctic-Neotropical migratory birds relative to the number of people in southeastern Brazil, the most populated region of South America. The frequency of occurrence of migrants, their distance of tolerance to people and the number of people were recorded in sample areas (circle plots with 20 m radius) on a 9 km stretch of urban beaches from November to February from 2009 to 2013. The probability of occurrence of Nearctic birds decreased as the number of people increased. When the number of people exceeded 20, the probability of occurrence of birds was almost zero. Furthermore, more than 95 % of birds moved off when people were within 16 m of reach. These results are discussed in the context of conservation actions since no management plan has been developed for migrant shorebirds that use urban beaches as stopover or wintering sites in developing countries.

Modeling of hydraulic and energy efficiency indicators for water supply systems

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Energy balance for ethyl alcohol production from crops

Energy requirements to produce ethyl alcohol from three different crops in Brazil (sugarcane, cassava, and sweet sorghum) were calculated. Figures are presented for the agricultural and industrial phases. The industrial phase is always more energy-intensive, consuming from 60 to 75 percent of the total energy. Sugarcane is the more efficient crop for ethyl alcohol production, followed by sweet sorghum and cassava from a net energy viewpoint. The utilization of sweet sorghum stems might increase the total energy gain from this crop to almost the same level as sugarcane. Cassava has a lower energy gain at the present state of agriculture in Brazil. Copyright © 1978 AAAS.

Conservation laws for Z(N) symmetric quantum spin models and their exact ground state energies

We derive an infinite set of conserved charges for some Z(N) symmetric quantum spin models by constructing their Lax pairs. These models correspond to the Potts model, Ashkin-Teller model and the particular set of self-dual Z(N) models solved by Fateev and Zamolodchikov [6]. The exact ground state energy for this last family of hamiltonians is also presented. © 1986.

Bioenergy from stillage anaerobic digestion to enhance the energy balance ratio of ethanol production

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Estudo sobre o panorama da energia elétrica no Brasil e tendências futuras

Pós-graduação em Engenharia Elétrica - FEB

Desenvolvimento de metodologia para implementação de eficiência energética em sistemas auxiliares de uma planta industrial siderúrgica semi-integrada

Pós-graduação em Engenharia Mecânica - FEG

Barriers to green buildings at two Brazilian engineering schools

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Estudo e análise de sistemas de refrigeração industrial integrados a plantas de processo químico

This work approaches the analysis of industrial refrigeration systems applied to a chemical processing industry that, in this case, consists of refrigeration machines, cooling tower system, cold water system and brine system. In this study it is highlighted the function and characteristics of different systems, including the main components, the most important features, their functionality and best practices. The motivation for this work is the fact that refrigeration systems are essential in many industrial processes, presenting a high energy consumption that is related to a significant parcel of production costs. It has aimed to understand the case studied in order to evaluate the energy efficiency of systems and to compare with Carnot efficiency and best available technologies. The assessment aims to identify irregularities, find opportunities and propose solutions that increases the performance of equipment and the overall system efficiency. Therefore, the studies intend to reduce the operation costs and generate gains for the company

Conforto térmico de edificações: análise crítica das tecnologias existentes

The rising in greenhouse gases emission as consequence of industrial expansion especially in developing countries is appointed as one of those reasons responsible for global warming. High-level temperatures are set as responsible for low productivity and high levels of discomfort. With the increase of worldwide energy demand, due to the population growth, this work aims to be an introductory text revising the current ventilation (mechanical and natural) and refrigeration technologies as well as low energy cooling techniques and architectural alternatives that seeks offering good ventilation and ideal buildings temperatures, making them sustainable. In addition, the text deals with the measurement instruments used to evaluate the parameters defined by international and national standards. At last, a case of study applies few concepts and technologies described in the text, introducing the results achieved, the limitations and suggestions to future works

Looming Changes in the Energy Economy

Over the next decade or two, the energy sector on which the world economy is based will undergo significant transformations. The fossil fuels on which the industrial revolution was built are on their way out. Nebraskans will face higher energy prices, but they will also produce more energy.

METROPOLITAN AND INDUSTRIAL BIRD PROBLEMS: Panel Discussion

As a pest control industry, we are interested in bird control, especially in areas of residence, commercial buildings, food plants, mills and elevators, commercial feed lots, farms, and even area wide controls in some of our cities. We run into all kinds of problems; I suppose you men do, too.

Estudo e análise de sistemas de refrigeração industrial integrados a plantas de processo químico

This work approaches the analysis of industrial refrigeration systems applied to a chemical processing industry that, in this case, consists of refrigeration machines, cooling tower system, cold water system and brine system. In this study it is highlighted the function and characteristics of different systems, including the main components, the most important features, their functionality and best practices. The motivation for this work is the fact that refrigeration systems are essential in many industrial processes, presenting a high energy consumption that is related to a significant parcel of production costs. It has aimed to understand the case studied in order to evaluate the energy efficiency of systems and to compare with Carnot efficiency and best available technologies. The assessment aims to identify irregularities, find opportunities and propose solutions that increases the performance of equipment and the overall system efficiency. Therefore, the studies intend to reduce the operation costs and generate gains for the company