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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
131

Exploring the strategies to implement a sustainable energy program in Hong Kong Public Hospitals

Ting, Terry 01 January 2017 (has links)
Healthcare is one of the most energy-intensive industries because of its 24 hour-a-day and 7-days-a-week operation model. Climate change, due to environmental pollution, has increased the incidence of respiratory disease, cardiovascular disease, and cancer, which further overload the financial burden of our healthcare system. The National Health Service Sustainable Development Unit suggested that a sustainable healthcare sector also requires using their resources in an efficient and responsible way. Hong Kong public hospitals are facing this problem along with high energy expenditure. The purpose of this qualitative, multiple site case study was to explore strategies for Hong Kong's public hospital leaders to develop and implement a sustainable program to reduce energy consumption. A purposive sample consisted of five local public hospital leaders that had successfully implemented a sustainable energy at their hospitals and received the 2014 Certificate of Merit of The Hong Kong Awards for Environmental Excellence. Semistructured interviews and document reviews were the data analysis methods for this study. The findings from the data analysis suggested that five major themes arose from the data: (a) external and internal driving forces, (b) leadership, (c) governance, (d) building a sustainable culture, and (e) performance measures. The recommendations of this study may lead to improving the use of energy in an efficient and responsible manner at the local public hospitals, reducing the hospital energy consumption cost, and reducing the disease incidences caused by environmental pollution.
132

Illumination properties and energy savings of a solar fiber optic lighting system balanced by artificial lights

Lingfors, David January 2013 (has links)
A solar fiber optic lighting system, SP3 from the Swedish company Parans Solar Lighting AB, has been installed in a study area/corridor test site. A collector is tracking the sun during daytime, focusing the direct sun irradiance via Fresnel lenses into optical fibers, which guide the solar light into the building. The illumination properties of the system have been characterized. The energy saving due to reduced need of artificial lighting have been calculated and methods for balancing the artificial lights in the test site have been evaluated. The illumination at the test site using solar light was at least as high as when using the artificial lights and even higher at very clear days. The luminous flux output (500 lm) was somewhat lower than specified by the manufacturer (550 lm) at 100 000 lx direct sun illuminance. The output at 130 000 lx was high 767±33 lm the sunlight coupling efficiency 23 %. However, for a 20 m SP3 system the luminous flux output (400 lm) at 100 000 lx was higher than specified (350 lm). The SP3 system of Parans provides high quality solar light. It has a fuller spectrum close to the spectrum of the sun compared to the fluorescent lights at the test site. The correlated color temperature of the system was 5800±300 K and the color rendering index 84.9±0.5. The lighting energy saved due to decreased need for artificial light was estimated to 19 % in Uppsala which has 1790 annual sun hours. The savings in Italy, which has 3400 sun hours, is 46 %. Additional saving, especially in warmer countries can be obtained due to decreased need for cooling in the building as the solar luminaires provide negligible heat to the indoor air. Economical saving could also be realized by improved well-being of the occupants spending time under the solar luminaires. Three ways of balancing the artificial light due to sunshine fluctuations have been investigated. The global horizontal irradiance could not be used as a control signal for balancing the artificial lights but a pyranometer attached to the SP3 sun tracking collector was usable. Also the signal from an indoor luxmeter sensor could be used for balancing the light. However the signal from the light sensor which makes the SP3 collector to track the sun is probably the most cost effective method as it would serve two purposes; tracking the sun and balancing the artificial lights.
133

Energideklaration av Svenska kyrkans byggnader i Växjö : utredning, deklaration och fördjupning nattkyla

Ericsson, Stefan, Evertsson, Torbjörn January 2008 (has links)
Detta examensarbete syftar till att utreda vilka av Svenska kyrkans byggnader i Växjö som ska energideklareras samt utföra en energideklaration av en kontorsbyggnad. I energideklarationen ingår det även att ge åtgärdsförslag för olika energibesparingsmöjligheter. En fördjupad studie i nattkylning av stommen har också utförts. Examensarbetet är uppdelat i tre huvuddelar, indelning av byggnader, utförande av energideklaration samt fördjupad studie av nattkyla. I den första delen delas byggnaderna in i grupper utifrån verksamhet och byggnadstyp och därefter utreds om de ska energideklareras. Målet med denna indelning av byggnader är att Svenska kyrkan ska få vetskap om vilka av deras byggnader som berörs av lagen om energideklarationer. I andra delen görs en energideklaration för en kontorsbyggnad. Det visar sig att det finns en hel del energibesparande åtgärder som kan göras i kontorsbyggnaden. En del av åtgärderna är endast enkla åtgärder som inte kräver något större ingrepp i byggnaden för att utföras. I den tredje delen genomförs en fördjupad studie i nattkylning av stommen i byggnader, där tung och lätt stomme jämförs gentemot varandra. För att utföra jämförelsen används simuleringsprogrammet IDA Klimat och Energi. Resultatet av simuleringen visar ingen besparing av energi till följd av nattkylning av stommen i den simulerade byggnaden, vilket leder fram till en parameterdiskussion om hur olika parametrar påverkar lönsamheten vid nattkyla. / This diploma work aims to investigate which of the Swedish church’s buildings in Växjö that needs to be energy declared and also to perform an energy declaration of an office building. In the energy declaration there’s also included measures for various energy-saving potential. An in-depth study of night-cooling of the framework has also been performed. This diploma work is divided into three main parts, classification of buildings, carrying out the energy declaration and a depth study of night-cooling of the building’s framework. In the first part buildings where divided into different groups on the basis of activities and type of building and then investigated whether to be energy declaration or not. The objective of this classification of buildings is that the Swedish church will know which of their buildings that’s affected by the law concerning energy declarations. The second part is an energy declaration of an office building. It turns out that there are a lot of energy-saving measures that can be done in the office building. Some of them are only simple measures that don’t require any major interference in the building to be performed. In the third part is carried out an in-depth study of night-cooling of buildings’ frameworks, where heavy and light frames are compared against each other. In order to carry out the comparison the simulation program IDA Climate and Energy was used. The results of the simulation shows no saving of energy as a result of night-cooling of the building frame in the simulated building, which leads to a parameter discussion on how various parameters affecting the profitability of night-cooling.
134

Energideklaration av Svenska kyrkans byggnader i Växjö : utredning, deklaration och fördjupning nattkyla

Ericsson, Stefan, Evertsson, Torbjörn January 2008 (has links)
<p>Detta examensarbete syftar till att utreda vilka av Svenska kyrkans byggnader i Växjö som ska energideklareras samt utföra en energideklaration av en kontorsbyggnad. I energideklarationen ingår det även att ge åtgärdsförslag för olika energibesparingsmöjligheter. En fördjupad studie i nattkylning av stommen har också utförts. Examensarbetet är uppdelat i tre huvuddelar, indelning av byggnader, utförande av energideklaration samt fördjupad studie av nattkyla. I den första delen delas byggnaderna in i grupper utifrån verksamhet och byggnadstyp och därefter utreds om de ska energideklareras. Målet med denna indelning av byggnader är att Svenska kyrkan ska få vetskap om vilka av deras byggnader som berörs av lagen om energideklarationer. I andra delen görs en energideklaration för en kontorsbyggnad. Det visar sig att det finns en hel del energibesparande åtgärder som kan göras i kontorsbyggnaden. En del av åtgärderna är endast enkla åtgärder som inte kräver något större ingrepp i byggnaden för att utföras. I den tredje delen genomförs en fördjupad studie i nattkylning av stommen i byggnader, där tung och lätt stomme jämförs gentemot varandra. För att utföra jämförelsen används simuleringsprogrammet IDA Klimat och Energi. Resultatet av simuleringen visar ingen besparing av energi till följd av nattkylning av stommen i den simulerade byggnaden, vilket leder fram till en parameterdiskussion om hur olika parametrar påverkar lönsamheten vid nattkyla.</p> / <p>This diploma work aims to investigate which of the Swedish church’s buildings in Växjö that needs to be energy declared and also to perform an energy declaration of an office building. In the energy declaration there’s also included measures for various energy-saving potential. An in-depth study of night-cooling of the framework has also been performed. This diploma work is divided into three main parts, classification of buildings, carrying out the energy declaration and a depth study of night-cooling of the building’s framework. In the first part buildings where divided into different groups on the basis of activities and type of building and then investigated whether to be energy declaration or not. The objective of this classification of buildings is that the Swedish church will know which of their buildings that’s affected by the law concerning energy declarations. The second part is an energy declaration of an office building. It turns out that there are a lot of energy-saving measures that can be done in the office building. Some of them are only simple measures that don’t require any major interference in the building to be performed. In the third part is carried out an in-depth study of night-cooling of buildings’ frameworks, where heavy and light frames are compared against each other. In order to carry out the comparison the simulation program IDA Climate and Energy was used. The results of the simulation shows no saving of energy as a result of night-cooling of the building frame in the simulated building, which leads to a parameter discussion on how various parameters affecting the profitability of night-cooling.</p>
135

Potential of Ventilation Radiators : Performance evaluation by numerical, analytical and experimental means

Myhren, Jonn Are January 2011 (has links)
Energy consumption for heating and ventilation of buildings is still in 2011considered far too high, but there are many ways to save energy and construct lowenergy buildings that have not been fully utilised. This doctoral thesis has focused onone of these - low temperature heating systems. Particular attention has been given tothe ventilation radiator adapted for exhaust-ventilated buildings because of itspotential as a low energy consuming, easily-operated, environmentally-friendlysystem that might also ensure occupant health and well-being. Investigations were based on Computational Fluid Dynamics (CFD) simulations andanalytical calculations, with laboratory experiments used for validation. Main conclusions: Low and very low temperature heating systems, such as floor heating, in general createan indoor climate with low air speeds and low temperature differences in the room, whichis beneficial for thermal comfort. A typical disadvantage, however, was found to beweakness in counteracting cold down-flow from ventilation air supply units in exhaustventilatedbuildings. with ventilation radiators, unlike most other low temperature systems, it was found thatthe risk of cold draught could be reduced while still maintaining a high ventilation rateeven in cold northern European winters. ventilation radiators were found to be more thermally efficient than traditional radiators. design of ventilation radiators could be further modified for improved thermal efficiency. at an outdoor temperature of -15 °C the most efficient models were able to give doublethe heat output of traditional radiators. Also, by substituting the most efficient ventilationradiators for traditional radiators operating at 55 °C supply water temperature, it wasfound that supply water temperature could be reduced to 35 °C while heat outputremained the same and comfort criteria were met. lowering the supply water temperature by 20 °C (as described above) could givecombined energy savings for heating and ventilation of 14-30 % in a system utilising aheat pump. supply water temperatures as low as 35 °C could increase potential for utilising lowtemperature heat sources such as sun-, ground-, water- or waste-heat. This would beparticularly relevant to new-built “green” energy-efficient buildings, but severaladvantages may apply to retrofit applications as well. Successful application of ventilation radiators requires understanding of relevant buildingfactors, and the appropriate number, positioning and size of radiators for best effect.Evaluation studies must be made at the level of the building as a whole, not just for theheating-ventilation system. This work demonstrated that increased use of well-designed ventilation radiatorarrangements can help to meet regulations issued in 2008 by the Swedish Departmentof Housing (Boverket BBR 16) and goals set in the Energy Performance of BuildingsDirective (EPBD) in the same year. / QC 20110328 / STEM Projektnummer:30326-1 Energieffektiva lågtemperatursystem i byggnader
136

Contributing to energy efficiency through a user-centered smart home

Dominici, Michele 03 June 2013 (has links) (PDF)
Smart homes are residences equipped with information and communication technologies that anticipate and respond to the needs of the occupants. Despite the numerous research and industrial efforts, today only few expensive smart homes have been built and sold. The reason behind this slow uptake is the technology-driven approach characterizing existing solutions. The doctoral Thesis aims at demonstrating that a smart home can provide functionalities designed with a user-centered approach, taking into account ergonomic considerations about domestic activity and human cognition. This is achieved in collaboration with cognitive ergonomists, which help "minding the gap" between human context and machine-understandable context. Using off-the-shelf and lightweight instrumentation (also minimizing privacy concerns), extending existing context modeling, reasoning and management tools and following the Ubiquitous Computing principles, the doctoral work led to the following achievements: (i) the inter-disciplinary design of suitable functionalities, in collaboration with cognitive ergonomists; (ii) the design of a context-aware system that captures and reasons about uncertain contextual information in a distributed fashion; (ii) the realization of a working prototype that demonstrates the provision of energy-saving and comfort-preserving functionalities.
137

En byggnads energibehov : En studie om energieffektivisering av en befintlig byggnad i södra Sverige

Åström Ylivainio, Frida January 2014 (has links)
The purpose of the study was to investigate the use and losses of energy in an existing older building. Another purpose was also to look through various options for heating systems with renewable energy in the building. The aim was to reduce the use and losses of energy. The first step was to study the related electricity bills of the building and also perform measurements and calculations of the building envelope and ventilation. The next step was to find out the possible actions for energy saving by performing measurements and calculations. To calculate the loss of energy a u-value was used, which describes a materials ability to conduct heat. The results of the energy calculations show what is reasonable to do in the building considering the energy savings versus economy. The study shows that it is important to first analyze and adjust the building envelope and ventilation before a new heating system is installed. That is to reduce the risk of an over-sizing of the heating system. It is not optimal to correct the entire building at energy efficiency because it is not economically feasible. All necessary actions of energy saving should be taken as a package where the most profitable should be picked out and executed. An older building is often of great value and therefore its appearance should be safeguarded at energy efficiency.
138

Προσαρμογή συχνότητας και τάσης λειτουργίας για τη βελτιστοποίηση κατανάλωσης ενέργειας επεξεργαστών

Σπηλιόπουλος, Βασίλειος 19 April 2010 (has links)
Η σύγχρονη αρχιτεκτονική στρέφεται σε λύσεις που έχουν ως στόχο την εξοικονόμηση ενέργειας, χωρίς όμως να επιβαρύνεται σε μεγάλο βαθμό η απόδοση του επεξεργαστή. Ιδιαίτερα οι υπερβαθμωτοί (superscalar) επεξεργαστές που επιτρέπουν εκτέλεση εκτός σειράς (out-of-order execution) διακρίνονται από υψηλή κατανάλωση ενέργειας, εξαιτίας των πολύπλοκων δομών που χρησιμοποιούν για την αύξηση της απόδοσης. Η δυναμική ρύθμιση τάσης – συχνότητας (DVFS) αποτελεί μία ευρέως χρησιμοποιούμενη τεχνική για την επίτευξη εξοικονόμησης ενέργειας. Μειώνοντας τη συχνότητα λειτουργίας ενός κυκλώματος, είναι δυνατόν να μειωθεί και η τάση τροφοδοσίας του κυκλώματος. Με τον τρόπο αυτό ελαττώνεται και η ενέργεια που καταναλώνει το κύκλωμα. Σκοπός της εργασίας είναι η ανάπτυξη ενός μηχανισμού πραγματικού χρόνου που θα ρυθμίζει τη συχνότητα και την τάση λειτουργίας ενός superscalar, out-of-order επεξεργαστή ώστε να επιτυγχάνεται εξοικονόμηση ενέργειας χωρίς μεγάλη μείωση της απόδοσης του επεξεργαστή. Αυτό μπορεί να επιτευχθεί ελαττώνοντας τη συχνότητα και την τάση κατά τις περιόδους που ο επεξεργαστής εκτελεί πολλές λειτουργίες μνήμης. Η εξομοίωση του μηχανισμού μας για μία σειρά από μετροπρογράμματα δείχνει ότι μπορούμε να επιτύχουμε μεγάλη εξοικονόμηση ενέργειας χωρίς σημαντική αύξηση του χρόνου εκτέλεσης των προγραμμάτων. / Modern research in computer architecture focuses on techniques whose purpose is to save energy, without much loss in processor's performance. Especially superscalar processors that allow out of order execution are characterized by high energy consumption, because of the complex structures the use in order to increase performance. Dynamic Voltage - Frequency Scaling (DVFS) is a widely used technique for energy saving. Reducing the frequency of the processor's clock, it is possible to reduce the supply voltage. In this way the consumed energy is also reduced. The purpose of this diploma thesis is to create a real time mechanism that will scale the frequency and the voltage of a superscalar, out of order processor so that the processor saves energy without much loss in processor's performance. This can be made by reducing the frequency and the voltage during the periods that the processor executes many memory functions. The simulation of our mechanism for a variety of benchmarks proved that we can save much energy without much increase in the benchmark's execution time.
139

Otimização de recursos e economia de energia em clusters usando virtualização. / Resource optimization and energy saving in clusters using virtualization.

Marcus Vinícius do Patrocínio Azevedo 19 July 2010 (has links)
Este trabalho propõe uma arquitetura reutilizável que permite a gerência de uma infraestrutura de suporte para aplicações Web, utilizando máquinas virtuais. O objetivo da arquitetura é garantir qualidade de serviço, atuando nos servidores físicos (hospedeiros) ou manipulando as máquinas virtuais, e avaliando o cumprimento das restrições de operação (tempo de resposta máximo). Além disso, através do uso racional dos recursos utilizados, a proposta visa à economia de energia. O trabalho também inclui uma avaliação de desempenho realizada sobre um sistema implementado com base na arquitetura. Esta avaliação mostra que a proposta é funcional e o quanto ela pode ser vantajosa do ponto de vista do uso de recursos, evitando desperdício, mantendo-se ainda a qualidade de serviço em níveis aceitáveis pela aplicação.
140

Dimensionering av pelletspanna : Ångkartläggning och dimensionering av en ny pelletspanna hos Fresenius Kabi i Kungsängen

Forsström Skeppar, Joacim January 2018 (has links)
The current boilers at the Brunna plant were installed in 1979 using oil and solvents to produce steam for the production and heating of the plant. To reduce the carbon dioxide emissions in compliance with Fresenius Kabi strategy a new biofuel boiler is about to be installed. Since the steam demand has been reduced during the years and it’s expensive to install a new boiler this study has been performed to calculate the actual steam demand for the plant at different scenarios. A smaller boiler requires a lower investment, achieves higher efficency and contributes to reduced carbon dioxide emissions. This report is intended to supply the management with information so that a decision regarding investments and employees can be made. The result is presented as different possible scenarios that are of great importance when deciding which boiler effect that is needed. Destillation, heating and the production have a major impact and must be considered when installing a new boiler. The results show that a boiler should be between 2-4 MW net effect depending on which scenario that is most likely to occur.

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