Determining the Adjustment Baseline Parameters to Define an Accurate Customer Baseline Load

Demand response is an energy resource that has gained increasing importance in the context of competitive electricity markets and of smart grids. New business models and methods designed to integrate demand response in electricity markets and of smart grids have been published, reporting the need of additional work in this field. In order to adequately remunerate the participation of the consumers in demand response programs, improved consumers’ performance evaluation methods are needed. The methodology proposed in the present paper determines the characterization of the baseline approach that better fits the consumer historic consumption, in order to determine the expected consumption in absent of participation in a demand response event and then determine the actual consumption reduction. The defined baseline can then be used to better determine the remuneration of the consumer. The paper includes a case study with real data to illustrate the application of the proposed methodology.

Impacto das opções de conceção em edifícios zero energy o caso dos grandes edifícios de serviços

Atualmente, o parque edificado é responsável pelo consumo de 40% da energia total consumida em toda a União Europeia. As previsões apontam para o crescimento do sector da construção civil, nomeadamente a construção de edifícios, o que permite perspetivar um aumento do consumo de energia nesta área. Medidas importantes, como o lançamento da Diretiva 2010/31/EU do Parlamento Europeu e do Conselho de 19 de Maio de 2010 relativa ao desempenho energético dos edifícios, abrem caminho para a diminuição das necessidades energéticas e emissões de gases de efeito de estufa. Nela são apontados objetivos para aumentar a eficiência energética do parque edificado, tendo como objetivo que a partir de 2020 todos os novos edifícios sejam energeticamente eficientes e de balanço energético quase zero, com principal destaque para a compensação usando produção energética própria proveniente de fontes renováveis. Este novo requisito, denominado nearly zero energy building, apresenta-se como um novo incentivo no caminho para a sustentabilidade energética. As técnicas e tecnologias usadas na conceção dos edifícios terão um impacto positivo na análise de ciclo de vida, nomeadamente na minimização do impacto ambiental e na racionalização do consumo energético. Desta forma, pretendeu-se analisar a aplicabilidade do conceito nearly zero energy building a um grande edifício de serviços e o seu impacto em termos de ciclo de vida a 50 anos. Partindo da análise de alguns estudos sobre o consumo energético e sobre edifícios de balanço energético quase nulo já construídos em Portugal, desenvolveu-se uma análise de ciclo de vida para o caso de um edifício de serviços, da qual resultou um conjunto de propostas de otimização da sua eficiência energética e de captação de energias renováveis. As medidas apresentadas foram avaliadas com o auxílio de diferentes aplicações como DIALux, IES VE e o PVsyst, com o objetivo de verificar o seu impacto através da comparação com estado inicial de consumo energético do edifício. Nas condições iniciais, o resultado da análise de ciclo de vida do edifício a 50 anos no que respeita ao consumo energético e respetivas emissões de CO2 na fase de operação foi de 6 MWh/m2 e 1,62 t/m2, respetivamente. Com aplicação de medidas propostas de otimização, o consumo e as respetivas emissões de CO2 foram reduzidas para 5,2 MWh/m2 e 1,37 t/m2 respetivamente. Embora se tenha conseguido reduzir ao consumo com as medidas propostas de otimização de energia, chegou-se à conclusão que o sistema fotovoltaico dimensionado para fornecer energia ao edifício não consegue satisfazer as necessidades energéticas do edifício no final dos 50 anos.

Análise custo-benefício da integração de painéis solares térmicos na reabilitação de um edifício

Dissertação de mestrado integrado em Engenharia Civil

Context-based services for mobile devices

The subject of this master’s thesis was developing a context-based reminder service for mobile devices. Possible sources of context were identified and analyzed. One such source is geographical location obtained via a GPS receiver. These receivers consume a lot of power and techniques and algorithms for reducing power consumptions were proposed and analyzed. The service was implemented as an application on a series 60 mobile phone. The application requirements, user interface and architecture are presented. The end-user experiences are discussed and possible future development and research areas are presented.

Energiansäästö kotitalouksien valaistuksessa Suomessa

Tässä työssä arvioidaan kotitalouksien energiansäästöpotentiaalia valaistuksen osalta Suomessa. Euroopan Unioni on ratifioinut päästövähennystavoitteen 20 % koskien kaikkia primäärienergiantuotantomuotoja. Päästövähennystavoite on tarkoitus toteuttaa vuoteen 2020 mennessä. Tässä kandidaatintyössä arvioidaan saavutettavissa olevaa energiansäästöpotentiaalia Suomessa kotitalouksissa laitesähkön osalta. Energiansäästöpotentiaalin arviointi perustuu hehkulampun korvaamismahdollisuuksien vertailuun. Valaistuksessa voidaan saavuttaa jopa 75 % sähkönsäästö, kun korvataan yksi 60 W hehkulamppu vastaavan valomäärän tuottavalla energiansäästölampulla. Kokonaisuudessa kotitalouksien valaistuksessa on tehostamispotentiaalia noin 60 %. Valaistuksen tehostamisella saavutetaan noin 1,5 TWh säästö Suomen kokonaissähkökulutuksessa. Saavutettavat säästöt voivat olla jopa suuremmatkin, jos käytetään lisäksi älykästä valonohjausta. Johtopäätöksenä voidaan todeta, että tehostamispotentiaalia on merkittävästi ja tehostaminen on yksittäiselle kotitaloudelle taloudellisesti kannattavaa. Energiansäästöpotentiaalin toteuttamisen vaikutuksia kansantalouteen ei ole arvioitu.

Reducing auxiliary power of a fluid bed boiler island

The aim of this thesis is to find and analyze different methods which reduce fluid bed boilers’ auxiliary power consumption. The objective is to examine the effects and feasibility of these methods. The literature part explains how fluid bed boilers work and what are the main sources of auxiliary power consumption. Designs and operation of these equipment are presented. The literature part also discusses the basics of auxiliary power consumption reduction and introduces four low pressure drop constructions. The experimental part inspects six different methods. Effects of these methods on the auxiliary power consumption are calculated and their impacts on the operation of the boiler are modeled. Calculations show that reasonable changes can reduce fluid bed boiler’s auxiliary power consumption by 2,1-10,2 %. Biggest reductions come from lower air coefficients, smaller bed a-level pressures and lower primary/secondary air –ratios. Models showed no problems with the smaller bed a-level pressures. With the lower air coefficients and smaller primary/secondary air –ratios the models showed a significant increase in the carbon monoxide levels.

High performance green buildings

This work aims to study and analyze strategies and measures to improve energy performance in residential and service buildings, in order to minimize energy losses and energy consumption. Due to the high energy dependence of European Union (EU), including Portugal and Slovenia, and high percentage of energy consumption in the building sector, there was a need to adopt strategies at European level with ambitious goals. This came to force EU - Member States to take measures to achieve the proposed targets for energy consumption reduction. To this end, EU - Member States have adapted the laws to their needs and formed specialized agencies and qualified experts on energy certification, which somehow evaluate buildings according to their performance. In this study, the external characteristics of the building in order to meet its thermal needs and from there to survey the existing and possible constructive solutions to be used at the envelope will be examined, in order to increase comfort and reduce the need of use technical means of air conditioning. The possibility of passive heating and ventilation systems also will be discussed. These techniques are developed in parallel with the deployment and design of the building. In this manner, to reduce the energy consumption, various techniques and technologies exploit natural resources. Thus, appear the more sustainable and efficient buildings, so-called Green Buildings have been appeared. The study ends with the identification of measures used in several buildings, proving the economic return in the medium to long term, as well as the satisfaction of their users.

Motivating sustainable goal choices and providing effective feedback

Overconsumption of natural resources and the associated environmental hazards are one of today’s most pressing global issues. In the western world, individual consumption in homes and workplaces is a key contributor to this problem. Reflecting the importance of individual action in this domain, this thesis focuses on studying and influencing choices related to sustainability and energy consumption made by people in their daily lives. There are three main components to this work. Firstly, this thesis asserts that people frequently make ineffective consumption reduction goal choices and attempts to understand the rationale for these poor choices by fitting them to goalsetting theory, an established theoretical model of behavior change. Secondly, it presents two approaches that attempt to influence goal choice towards more effective targets, one of which deals with mechanisms for goal priming and the other of which explores the idea that carefully designed toys can exert influence on children’s long term consumption behavior patterns. The final section of this thesis deals with the design of feedback to support the performance of environmentally sound activities. Key contributions surrounding goals include the finding that people choose easy sustainable goals despite immediate feedback as to their ineffectiveness and the discussion and study of goal priming mechanisms that can influence this choice process. Contributions within the design of value instilling toys include a theoretically grounded framework for the design of such toys and a completed and tested prototype toy. Finally, contributions in designing effective and engaging energy consumption feedback include the finding that negative feedback is best presented verbally compared with visually and this is exemplified and presented within a working feedback system. The discussions, concepts, prototypes and empirical findings presented in this work will be useful for both environmental psychologists and for HCI researchers studying eco-feedback.

A influência de decisões arquitetônicas na eficiência energética do Campus vol. 1/UFRN

Building design is an effective way to achieve HVAC energy consumption reduction. However, this potentiality is often neglected by architects due to the lack of references to support design decisions. This works intends to propose architectural design guidelines for energy efficiency and thermal performance of Campus/UFRN buildings. These guidelines are based on computer simulations results using the software DesignBuilder. The definition of simulation models has begun with envelope variables, partially done after a field study of thirteen buildings at UFRN/Campus. This field study indicated some basic envelope patterns that were applied in simulation models. Occupation variables were identified with temperature and energy consumption monitoring procedures and a verification of illumination and equipment power, both developed at the Campus/UFRN administration building. Three simulation models were proposed according to different design phases and decisions. The first model represents early design decisions, simulating the combination of different types of geometry with three levels of envelope thermal performance. The second model, still as a part of early design phase, analyses thermal changes between circulation halls lateral and central and office rooms, as well as the heat fluxes and monthly temperatures in each circulation hall. The third model analyses the influence of middle-design and detail design decisions on energy consumption and thermal performance. In this model, different solutions of roofs, shading devices, walls and external colors were simulated. The results of all simulation models suggest a high influence of thermal loads due to the incidence of solar radiation on windows and surfaces, which highlights the importance of window shading devices, office room orientation and absorptance of roof and walls surfaces

Projeto de um edifício para fins educacionais com foco na racionalização do consumo de água

The urban growth without the prior infrastructure has caused many environmental impacts such as the damage to quality of the water resources in the cities. Along with natural scarcity in some regions, this is one of the factors that limit the availability of drinking water. As a result, the conservation of drinking water is becoming one of the major concerns in sustainable architectural projects. Within this context, this dissertation proposes to develop the design of an educational building focusing on water consumption rationalization. The proposed project is located in UFRN Campus at Currais Novos, an area of warm and dry climate and low rainfall. The proposal seeks to integrate ways to reduce water consumption o to architecture, in order to exploit the advantages and savings. After quantifying the benefits achieved, it was concluded that it is possible to reduce significantly the drinking water consumption in educational buildings in universities using three principles: reduction the water consumption at the point of use, replacement of the water source and internal recycling. Calculations and simulations indicated that the proposed building may have water consumption up to 56% lower than if it would be provided by conventional facilities. Rationalization of water consumption brings direct and indirect benefits, with influences on the environmental, social and economic fields

Ajuste automático e otimização do tempo de espera (Idle time) em bombeio mecânico de petróleo

The present work presents an algorithm proposal, which aims for controlling and improving idle time to be applied in oil production wells equipped with beam pump. The algorithm was totally designed based on existing papers and data acquired from two Potiguar Basin pilot wells. Oil engineering concepts such as submergence, pump off, Basic Sediments and Water (BSW), Inflow Performance Relationship (IPR), reservo ir pressure, inflow pressure, among others, were included into the algorithm through a mathematical treatment developed from a typical well and then extended to the general cases. The optimization will increase the well production potential maximum utilization having the smallest number of pumping unit cycles directly reflecting on operational cost and electricity consumption reduction

Desempenho de um motor de trator agrícola em bancada dinamométrica com biodiesel de óleo de frango e misturas binárias com óleo diesel

O Brasil, terceiro maior produtor de biodiesel do mundo e terceiro maior produtor mundial de frango, pode incrementar, na sua matriz energética, o uso de óleo oriundo de aves como alternativa aos combustíveis fósseis e à redução da dependência do óleo de soja para esse fim. O país dispõe de mais de 350 milhões de litros de óleo de frango por ano. Considerando a aplicação dos combustíveis alternativos para os motores a diesel, em máquinas agrícolas, o trabalho teve por objetivo avaliar o desempenho do motor de um trator agrícola de 53kW acoplado pela TDP em bancada dinamométrica, operando com biodiesel metílico de óleo de frango e misturas com óleo diesel, sendo: B5 (testemunha), B20, B40, B60, B80 e B100. Avaliaram-se a potência, o torque, a reserva de torque, o consumo de combustível, o consumo de energia e a eficiência térmica do motor. O ensaio foi instalado com delineamento inteiramente casualizado (DIC) em esquema fatorial com seis tratamentos. Os resultados foram submetidos à análise de variância e as médias ajustadas por equações de regressão. Foram observadas perdas na geração de potência e torque, aumento no consumo de combustível, redução do consumo energético e melhoria na eficiência térmica do motor, de acordo com o aumento da proporção de biodiesel na mistura.

Production of an axial piston: Impacts resulting from the substitution of steel by a polymer-based material

The substitution of steel as a raw material in the production of axial pistons for pressure washers by polyphthalamide, polytetrafluoroethylene and glass fiber-based composite was studied. The new production process with composite consists of only two steps, while the production of the steel piston is to comprise of thirteen steps. This replacement would result in an estimated reduction of 80% of water consumption, 83% of electricity consumption, 73% of the total cost and 88% of the final mass. With regard to the main mechanical properties required for the end product, the composite was found to withstand the critical axial loads and it shows acceptable wear resistance in an environment without lubrication, an additional advantage of this replacement. © 2012 Elsevier Ltd. All rights reserved.

Análise de dificuldades técnicas e econômicas na inserção da cogeração pelas usinas sucroalcooleiras

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Determinação de indicadores de eficiência e racionalidade energética na produção de etanol com a aplicação da lógica fuzzy

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)