Sistema fotovoltaico interligado á rede eletrica no Campus da UNESP-FEG Guaratinguetá

Solar energy can be considered the largest source of energy available on earth and has attracted in recent decades, attention and interest for its rational use. The use of energy sources in a sustainable manner is essential to the survival of future generations, due to the scarcity of natural resources and their exploitation in a disorderly way. Studies related to the applications of renewable sources becomes then relevant, given its great importance as regards the conscious use of resources provided by nature, with the least possible impact on it. The present study presents an evaluation of generation potential and feasibility of implementing a solar photovoltaic connected to the grid and connected to the roofs of some buildings of the Faculty of Engineering of Guaratinguetá - FEG, to supply the demand of electric energy consumption on campus and attempting to inject a possible surplus power generation in local power grid, increasing network capacity and reducing peak loads

Aplicação do regulamento técnico da qualidade do nível de eficiência energética em edificações residenciais

The research shows that increasing the consumption of energy by households is growing rapidly and without adequate planning, due to population growth and therefore an increase in energy consumption. With the current concerns of sustainability and energy efficiency by industry, there is the need to prove to population that there are many ways to incorporate sustainable practices to their daily lives, starting from by their own residence. The quality certification of the energy efficiency level in residential buildings, shows how one can influence and improve housing issues on sustainable actions as rooted in our country

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)

Bio-energy conversion cost: a new index to evaluate the bioeconomic eficiency

This study evaluated a nonlinear programming excel workbook PPFR (http://www.fmva.unesp.br/ppfr) for determining the optimum nutrient density and maximize margins. Two experiments were conducted with 240 one-day-old female chicks and 240 one-day-old male chicks distributed in 48 pens (10 chicks per pen, 4 replicates) in a completely randomized design. The treatments include the average price history (2009s and 2010s) for broiler increased and decreased by 25% or 50% (5 treatments to nonlinear feed formulation) and 1 linear feed formulation. Body gain, feed intake, feed conversion were measured at 21, 42 and 56 d of age. Chicks had ad libitum access to feed and water in floor pens with wood shavings as litter. The bio-economic Energy Conversion [BEC= (Total energy intake*Feed weighted cost per kg)/ (Weight gain*kg live chicken cost)] was more sensitive for measuring the bio-economic performance for broilers, and especially with better magnitude. This allowed a better assessment of profitability, the rate of growth and not just energy consumption, the production of broilers, by incorporating energy consumption, allowing for more sensitivity to the new index (BEC). The BEC was demonstrated that the principle of nonlinear formulation minimizes losses significantly (P<0.05), especially under unfavorable conditions the price of chicken in the market. Thus, when considering that a diet of energy supply shows up as the most expensive item of a formulation, it should compose necessarily the formula proposed for a bio-economic index. Thus, there is need to evaluate more accurately, not only the ingredients of a ration, but the impact of nutrients on the stability of a solution, mainly due to the energy requirement. This strategy promotes better accuracy for decision making under conditions of uncertainty, to find alternative post-formulation. From the above, both weight gain and feed conversion, as traditional performance indicators, cannot finalize or predict a performance evaluation of an economic system creating increasingly intense and competitive. Thus, the energy concentration of the diet becomes more important definition to feed formulator, by directly impact profit activity by interactions with the density of nutrients. This allowed a better evaluation of profitability, the rate of energy performance for broilers, by incorporating the energy consumption formula, allowing more sensitivity to the new index (BEC). These data show that nonlinear feed formulation is a toll to offer new opportunities for poultry production to improved profitability.

Efficiency in Brazil's industrial sectors in terms of energy and sustainable development

This article evaluates the efficiency of Brazil's industrial sectors from 1996 to 2009, taking into account energy consumption and respective contributions to the country's economic and social aspects. This analysis used a mathematical programming method called Data Envelopment Analysis (DEA), which enabled, from the SBM model and the window analysis, to evaluate the ability of industries to reduce energy consumption and fossil-fuel CO2 emissions (inputs), as well as to increase the Gross Domestic Product (GDP) by sectors, the persons employed and personnel expenses (outputs). The results of this study indicated that the Textile sector is the most efficient industrial sector in Brazil, according to the variables used, followed by these sectors: Foods and Beverages, Chemical, Mining, Paper and Pulp, Nonmetallic and Metallurgical.

Gestão energética nos setores transversais para redução do consumo de energia em uma empresa automobilística

Pós-graduação em Engenharia de Produção - FEG

Methodology of CO2 emission evaluation in the life cycle of office building facades

The construction industry is one of the greatest sources of pollution because of the high level of energy consumption during its life cycle. In addition to using energy while constructing a building, several systems also use power while the building is operating, especially the air-conditioning system. Energy consumption for this system is related, among other issues, to external air temperature and the required internal temperature of the building. The facades are elements which present the highest level of ambient heat transfer from the outside to the inside of tall buildings. Thus, the type of facade has an influence on energy consumption during the building life cycle and, consequently, contributes to buildings' CO2 emissions, because these emissions are directly connected to energy consumption. Therefore, the aim is to help develop a methodology for evaluating CO2 emissions generated during the life cycle of office building facades. The results, based on the parameters used in this study, show that facades using structural glazing and uncolored glass emit the most CO2 throughout their life cycle, followed by brick facades covered with compound aluminum panels or ACM (Aluminum Composite Material), facades using structural glazing and reflective glass and brick facades with plaster coating. On the other hand, the typology of facade that emits less CO2 is brickwork and mortar because its thermal barrier is better than structural glazing facade and materials used to produce this facade are better than brickwork and ACM. Finally, an uncertainty analysis was conducted to verify the accuracy of the results attained. (C) 2011 Elsevier Inc. All rights reserved.

Carbothermal Reduction of Iron Ore Applying Microwave Energy

This paper presents the results of a study on carbothermal reduction of iron ore made under the microwave field in equipment specially developed for this purpose. The equipment allows the control of radiated and reflected microwave power, and therefore measures the microwave energy actually applied to the load in the reduction process. It also allows performing energy balances and determining the reaction rate with high levels of confidence by simultaneously measuring temperature and mass of the material upon reduction with high reproducibility. We used a microwave generator of 2.45?GHz with variable power up to 3000?W. Self-reducing pellets under argon atmosphere, containing iron ore and petroleum coke, with 3.5?g of mass and 15?mm of diameter were declined. We obtained the kinetic curves of reduction of iron ore and of energy consumption to the process in the maximum electric field, in the maximum magnetic field and at different values of power/mass. The data allow analyzing how the microwave energy was actually consumed in the reduction of ore.

A Low Consumption Real Time Environmental Monitoring System for Smart Cities based on ZigBee Wireless Sensor Network

Nowadays, there is an increasing interest in wireless sensor networks (WSN) for environmental monitoring systems because it can be used to improve the quality of life and living conditions are becoming a major concern to people. This paper describes the design and development of a real time monitoring system based on ZigBee WSN characterized by a lower energy consumption, low cost, reduced dimensions and fast adaptation to the network tree topology. The developed system encompasses an optimized sensing process about environmental parameters, low rate transmission from sensor nodes to the gateway, packet parsing and data storing in a remote database and real time visualization through a web server.

Utilizzo delle bande dell’Infrarosso Termico in tecniche di remote sensing per applicazioni in ambito urbano

Il presente studio si concentra sulle diverse applicazioni del telerilevamento termico in ambito urbano. Vengono inizialmente descritti la radiazione infrarossa e le sue interazioni con l’atmosfera terrestre, le leggi principali che regolano lo scambio di calore per irraggiamento, le caratteristiche dei sensori e le diverse applicazioni di termografia. Successivamente sono trattati nel dettaglio gli aspetti caratteristici della termografia da piattaforma satellitare, finalizzata principalmente alla valutazione del fenomeno dell'Urban Heat Island; vengono descritti i sensori disponibili, le metodologie di correzione per gli effetti atmosferici, per la stima dell'emissività delle superfici e per il calcolo della temperatura superficiale dei pixels. Viene quindi illustrata la sperimentazione effettuata sull'area di Bologna mediante immagini multispettrali ASTER: i risultati mostrano come sull'area urbana sia riscontrabile la presenza dell'Isola di Calore Urbano, anche se la sua quantificazione risulta complessa. Si procede quindi alla descrizione di potenzialità e limiti della termografia aerea, dei suoi diversi utilizzi, delle modalità operative di rilievo e degli algoritmi utilizzati per il calcolo della temperatura superficiale delle coperture edilizie. Tramite l’analisi di alcune esperienze precedenti vengono trattati l’influenza dell’atmosfera, la modellazione dei suoi effetti sulla radianza rilevata, i diversi metodi per la stima dell’emissività. Viene quindi introdotto il progetto europeo Energycity, finalizzato alla creazione di un sistema GeoWeb di supporto spaziale alle decisioni per la riduzione di consumi energetici e produzione di gas serra su sette città dell'Europa Centrale. Vengono illustrate le modalità di rilievo e le attività di processing dei datasets digitali per la creazione di mappe di temperatura superficiale da implementare nel sistema SDSS. Viene infine descritta la sperimentazione effettuata sulle immagini termiche acquisite nel febbraio 2010 sulla città di Treviso, trasformate in un mosaico georiferito di temperatura radiometrica tramite correzioni geometriche e radiometriche; a seguito della correzione per l’emissività quest’ultimo verrà trasformato in un mosaico di temperatura superficiale.

Teoria e pratica dell'architettura solare - Morfologia, rendimento, strategia progettuale

La recente Direttiva 31/2010 dell’Unione Europea impone agli stati membri di riorganizzare il quadro legislativo nazionale in materia di prestazione energetica degli edifici, affinchè tutte le nuove costruzioni presentino dal 1° gennaio 2021 un bilancio energetico tendente allo zero; termine peraltro anticipato al 1° gennaio 2019 per gli edifici pubblici. La concezione di edifici a energia “quasi” zero (nZEB) parte dal presupposto di un involucro energeticamente di standard passivo per arrivare a compensare, attraverso la produzione preferibilmente in sito di energia da fonti rinnovabili, gli esigui consumi richiesti su base annuale. In quest’ottica la riconsiderazione delle potenzialità dell’architettura solare individua degli strumenti concreti e delle valide metodologie per supportare la progettazione di involucri sempre più performanti che sfruttino pienamente una risorsa inesauribile, diffusa e alla portata di tutti come quella solare. Tutto ciò in considerazione anche della non più procrastinabile necessità di ridurre il carico energetico imputabile agli edifici, responsabili come noto di oltre il 40% dei consumi mondiali e del 24% delle emissioni di gas climalteranti. Secondo queste premesse la ricerca pone come centrale il tema dell’integrazione dei sistemi di guadagno termico, cosiddetti passivi, e di produzione energetica, cosiddetti attivi, da fonte solare nell’involucro architettonico. Il percorso sia analitico che operativo effettuato si è posto la finalità di fornire degli strumenti metodologici e pratici al progetto dell’architettura, bisognoso di un nuovo approccio integrato mirato al raggiungimento degli obiettivi di risparmio energetico. Attraverso una ricognizione generale del concetto di architettura solare e dei presupposti teorici e terminologici che stanno alla base della stessa, la ricerca ha prefigurato tre tipologie di esito finale: una codificazione delle morfologie ricorrenti nelle realizzazioni solari, un’analisi comparata del rendimento solare nelle principali aggregazioni tipologiche edilizie e una parte importante di verifica progettuale dove sono stati applicati gli assunti delle categorie precedenti

Nano-Power Integrated Circuits for Energy Harvesting

The energy harvesting research field has grown considerably in the last decade due to increasing interests in energy autonomous sensing systems, which require smart and efficient interfaces for extracting power from energy source and power management (PM) circuits. This thesis investigates the design trade-offs for minimizing the intrinsic power of PM circuits, in order to allow operation with very weak energy sources. For validation purposes, three different integrated power converter and PM circuits for energy harvesting applications are presented. They have been designed for nano-power operations and single-source converters can operate with input power lower than 1 μW. The first IC is a buck-boost converter for piezoelectric transducers (PZ) implementing Synchronous Electrical Charge Extraction (SECE), a non-linear energy extraction technique. Moreover, Residual Charge Inversion technique is exploited for extracting energy from PZ with weak and irregular excitations (i.e. lower voltage), and the implemented PM policy, named Two-Way Energy Storage, considerably reduces the start-up time of the converter, improving the overall conversion efficiency. The second proposed IC is a general-purpose buck-boost converter for low-voltage DC energy sources, up to 2.5 V. An ultra-low-power MPPT circuit has been designed in order to track variations of source power. Furthermore, a capacitive boost circuit has been included, allowing the converter start-up from a source voltage VDC0 = 223 mV. A nano-power programmable linear regulator is also included in order to provide a stable voltage to the load. The third IC implements an heterogeneous multisource buck-boost converter. It provides up to 9 independent input channels, of which 5 are specific for PZ (with SECE) and 4 for DC energy sources with MPPT. The inductor is shared among channels and an arbiter, designed with asynchronous logic to reduce the energy consumption, avoids simultaneous access to the buck-boost core, with a dynamic schedule based on source priority.

Energy-efficient Communication and Estimation in Wireless Sensor Networks

This thesis focuses on the energy efficiency in wireless networks under the transmission and information diffusion points of view. In particular, on one hand, the communication efficiency is investigated, attempting to reduce the consumption during transmissions, while on the other hand the energy efficiency of the procedures required to distribute the information among wireless nodes in complex networks is taken into account. For what concerns energy efficient communications, an innovative transmission scheme reusing source of opportunity signals is introduced. This kind of signals has never been previously studied in literature for communication purposes. The scope is to provide a way for transmitting information with energy consumption close to zero. On the theoretical side, starting from a general communication channel model subject to a limited input amplitude, the theme of low power transmission signals is tackled under the perspective of stating sufficient conditions for the capacity achieving input distribution to be discrete. Finally, the focus is shifted towards the design of energy efficient algorithms for the diffusion of information. In particular, the endeavours are aimed at solving an estimation problem distributed over a wireless sensor network. The proposed solutions are deeply analyzed both to ensure their energy efficiency and to guarantee their robustness against losses during the diffusion of information (against information diffusion truncation more in general).

Edilizia sociale e prestazioni energetiche in un caso di studio a queimados all'interno del programa minha casa, minha vida: Analisi e proposte di miglioramento

Social Housing and energy performance in a study case in Queimados within the Programa Minha Casa Minha Vida: analysis and proposals for improvement. The thesis in based on a personal experience lived in Brazil, working with a firm that deals with the construction of housing, for the population with incomes between 1.600 R$ and 3.100 R$ per month, in the Programa Minha Casa Minha Vida. Thanks to the construction site and contact with the local people, it was possible to attend to the construction phases and to understand the pros and cons of this Program. Working with the company made also possible to know the costs of the construction and to see that they reached the limit budget imposed by the Program (160.000 R$). Between the critical aspects of the program there is the fact that it doesn’t deal with the energy consumptions of buildings. For that reason it was interesting to calculate the energy requirements for cooling- using the software EnergyPlus and Legacy Opens Studio plug-in for Google Sketchup- and, later, to try to propose ideas for improving performances and reduce energy consumption introducing: increase in the wall mass, frame windows and patio doors, exterior blinds, wall shading on the west side. From the analysis of these simulations, considering the decrease of energy requirements for cooling, the decrease of operative and mean radiant temperatures and costs, the most convenient proposal was the exterior curtain. As all these assumptions were too expensive for the program it was analyzed how the behavior of the inhabitants influence energy consumption. Thinking of an intelligent ventilation –opening windows while the outside temperature is lower than the inside one- the reduction of energy requirements is about 27%. These result is really important, if you consider that it is obtained without spending more money.

On the accuracy of Software-based Energy Estimation Techniques

This paper examines the accuracy of software-based on-line energy estimation techniques. It evaluates today’s most widespread energy estimation model in order to investigate whether the current methodology of pure software-based energy estimation running on a sensor node itself can indeed reliably and accurately determine its energy consumption - independent of the particular node instance, the traffic load the node is exposed to, or the MAC protocol the node is running. The paper enhances today’s widely used energy estimation model by integrating radio transceiver switches into the model, and proposes a methodology to find the optimal estimation model parameters. It proves by statistical validation with experimental data that the proposed model enhancement and parameter calibration methodology significantly increases the estimation accuracy.