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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.
111

Leveraging Vehicle-to-Infrastructure Communications for Adaptive Traffic Signaling and Better Energy Utilization

Agrawal, Manas 30 August 2013 (has links)
No description available.
112

Energy savings potential of building envelope refurbishment in Swedish single-family houses

Kousah, Rami January 2023 (has links)
Sweden has ca. 2 million single family houses (SFH) housing 52% of the population and representing 44.6% of the overall heated floor area. SFHs account for 39.5% of the total heating demand in Sweden. Energy consumption in older SFHs is much higher than in new ones. SFHs built in the 1960s consume ca. 170% of the annual heating energy demand of SFH built in the 2010s. This study aims to explore the energy savings potential in existing SFHs built between 1960 and 1975 in Sweden through refurbishment of elements of the building envelope and analyze their energy and costefficiency of these measures. Furthermore, it aims to study the effects of variations in climate in Sweden on the energy and cost efficiency of these measures. A hypothetical un-refurbished SFH was modeled and defined using energy simulation tool IDA-ICE based on statistical data and relevant literature reviews. Variations in climate between regions of Sweden were analyzed and 4 suitable locations were suggested to place the hypothetical model in. Suitable building envelope refurbishmentmeasures were selected for the elements of the building envelope. These measures were (a) adding extra insulation to the outer side of external wall (b) replacing and insulating the slab on ground (c) insulating the cold attic on top the existing horizontal slab, and (d) replacing the exiting external doors and windows. Suggested U-values for renovated SFHs from Boverket were used as a goal for the suggested refurbishment measures to reach. Energy performance simulations were performed to estimate savings potential in energy used for heating purposes for the un-refurbished building and each of the suggested measures. Life cycle cost (LCC) study using UPV* method was performed over a lifespan of 30 years. The results of the energy performance simulation showed energy savings potential in all the suggested measures, ranging from ca. 6% to ca. 20% with the measure of replacing the external doors and windows had the most savings potential. The study highlighted rate of improvement in U-values, surface area within which heat losses are occurring, status of thermal bridges, and differences in temperature between air and soil as factors effecting the energy savings potential. The results showed no significant effects of changing locations on the savings potential. LCC analysis showed that the measure of adding extra insulation in the cold attic is the most cost-efficient. It also showed that higher heating demands in colder climate led to more significant role for the energy savings potential in determining the cost efficiency, while the initial costs played a bigger role in warmer climate. The study also showed that choosing materials and products with longer lifespan in addition to having a good energy savings potential may lead to a change in results on the cost-efficiency analysis. The study concludes with highlighting the energy savings potential in building envelope refurbishment and the importance of including both and energy and cost efficiency perspectives when choosing refurbishment measures for existing SFH.
113

Assessing the Energy Efficiency of Small Transit Systems; A Case Study of the Miami Metro Bus Service

Kazungu, Conny Sidi 26 April 2012 (has links)
No description available.
114

Les technologies nouvelles ont-elles un rôle à jouer sur un marché très concurrentiel de la Russie postsoviétique, le marché du chauffage ? (Période étudiée 1991-2008) / Do new technologies have a part to play in the very competitive heating market of the post-soviet Russia? (Period studied 1991-2008)

Lochoshvili, Maksym 16 October 2009 (has links)
Sur un exemple concret d’entreprise française disposant des technologies innovantes dans les domaines du chauffage et de la distribution d’eau et ayant un projet d’expansion vers un nouveau marché, en l’occurrence, le marché russe, l’auteur montre l’importance de ces technologies pour accéder au marché fortement différent du marché domestique. Au sein du secteur du chauffage dans un pays où, à cause des conditions climatiques froides, le besoin de se chauffer présente un besoin vital, où le retard technologique dû au phénomène historique du monopole du chauffage central collectif est particulièrement ressenti et où le marché est en pleine formation avec la montée de la concurrence, les technologies nouvelles ont sans doute un rôle capital à jouer. Comment l’entreprise porteuse de ces technologies doit-t-elle aborder le marché russe certes très prometteur, mais fragile surtout en cette période délicate de la crise économique mondiale? Quels en sont les risques et les perspectives ? Comment réussir ce marché ? Comment mettre en valeur et transférer de nouvelles solutions technologiques ? Quels sont les avantages de ce transfert pour l’entreprise, mais également pour son partenaire local, pour la région visée et pour l’Etat receveur ? Telles sont les questions que l’auteur se pose. Le rôle des technologies nouvelles va certainement au-delà d’un secteur ou d’un domaine d’activité : les technologies nouvelles apportées par des entreprises occidentales ont sans doute accéléré, en ce qui concerne la Russie, le passage d’un système économique du type soviétique vers un système de libre-échange que l’on connait sous le terme d’économie de marché. / On a specific example of a French company having innovative technologies in the field of heating and water distribution, and realizing an expansion project to a new market, in this case, the Russian market, the author shows the importance of technologies when penetrating a market strongly different from the domestic one. Within the heating sector in the country where, because of a cold climate, the need to feel warm is a vital need, where the technological backwardness due to the historical phenomenon of the central residential heating monopoly is obvious, and where market is taking shape and competition is now growing, new technologies have without doubt a capital part to play. How should a company with such technologies approach the Russian market certainly very promising, but also fragile especially in this delicate period of the world economic crisis? What are the risks and the perspectives for the company? How to succeed in this market? How to enhance the value and to transfer new technological solutions? What advantages does this transfer bring to the company, but also to the company’s local partner, to the targeted region, and to the receiving country? These are questions the author asks himself. The role of new technologies is certainly beyond a sector or a field of activity: the new technologies brought by western companies undoubtedly accelerated, as Russia is concerned, the change from the Soviet-type economic system to a free-market system, known as the market economy.
115

Data-Driven Predictions of Heating Energy Savings in Residential Buildings

Lindblom, Ellen, Almquist, Isabelle January 2019 (has links)
Along with the increasing use of intermittent electricity sources, such as wind and sun, comes a growing demand for user flexibility. This has paved the way for a new market of services that provide electricity customers with energy saving solutions. These include a variety of techniques ranging from sophisticated control of the customers’ home equipment to information on how to adjust their consumption behavior in order to save energy. This master thesis work contributes further to this field by investigating an additional incentive; predictions of future energy savings related to indoor temperature. Five different machine learning models have been tuned and used to predict monthly heating energy consumption for a given set of homes. The model tuning process and performance evaluation were performed using 10-fold cross validation. The best performing model was then used to predict how much heating energy each individual household could save by decreasing their indoor temperature by 1°C during the heating season. The highest prediction accuracy (of about 78%) is achieved with support vector regression (SVR), closely followed by neural networks (NN). The simpler regression models that have been implemented are, however, not far behind. According to the SVR model, the average household is expected to lower their heating energy consumption by approximately 3% if the indoor temperature is decreased by 1°C.
116

Přínos kohezní politiky ke snižování energetické náročnosti prostředí v České republice / Benefits of Cohesion Policy for reducing energy consumption in the Czech Republic

Yonová, Kateřina January 2010 (has links)
This diploma thesis deals with the evaluation of the benefit of cohesion policy to reduce energy consumption and preserve an attractive environment in the Czech Republic. The aim is to determine the spatial distribution and allocation of approved financial resources from fields of support related to energy savings. The primary focus is on the Operational Programme Environment - priority axis Sustainable Use of Energy and the Operational Programme Enterprise and Innovation --priority axis Energy Efficient, which are subjects of the analysis. In conclusion is summarized current information about the form of future cohesion policy after 2013.
117

Ανάπτυξη και εφαρμογή μεθοδολογίας περιβαλλοντικής αξιολόγησης σε ηλεκτροχρωμικά παράθυρα / Development of an environmental evaluation methodology and application for electrochromic windows

Συρράκου, Ελένη 31 May 2007 (has links)
Στη διατριβή αυτή έχει αναπτυχθεί ένας νέος συνδυασμός της Ανάλυσης Κύκλου Ζωής (ΑΚΖ) και της Ανάλυσης Οικολογικής Απόδοσης, που εφαρμόζεται για την αξιολόγηση της περιβαλλοντικής και ενεργειακής απόδοσης και της απόδοσης κόστους ενός πρότυπου ηλεκτροχρωμικού παραθύρου, η οποία έχει σκοπό να χρησιμοποιηθεί ως διάταξη εξοικονόμησης ενέργειας σε κτήρια. Ο κύριος στόχος είναι να επισημάνουμε πώς η συγκεκριμένη μέθοδος συμπληρώνει τις δύο μεθόδους, ενσωματώνοντας τα ιδιαίτερα πλεονεκτήματά τους σε ένα πληρέστερο και πιο ισχυρό διαγνωστικό εργαλείο. Η αποδοτικότητα της μεθόδου αποδεικνύεται με εφαρμογή σε έναν ηλεκτροχρωμικό υαλοπίνακα (K-Glass/WO3/πολυμερής ηλεκτρολύτης/V2O5/K-Glass), διαστάσεων 40cmx40cm. Αξιολογείται ολόκληρος ο κύκλος ζωής του εφαρμόζοντας τη μέθοδο της ΑΚΖ (ISO 14040). Για να μετρηθεί και να καταγραφεί η οικολογική απόδοση, χρησιμοποιούνται δείκτες περιβαλλοντικής απόδοσης, οι οποίοι βασίζονται σε ισοζύγια υλικών και ενέργειας και ορίστηκαν λαμβάνοντας υπόψη διάφορες παραμέτρους, (σενάριο ελέγχου, προσδοκώμενος χρόνος ζωής, κλιματικές συνθήκες, κόστος αγοράς). Ο συνδυασμός των αποτελεσμάτων οδηγεί σε σημαντικά συμπεράσματα για τον συνδυασμό ιδιοτήτων και τις πιθανές βελτιώσεις, που μπορεί να χρησιμοποιηθούν στη λήψη αποφάσεων για το σχεδιασμό και την ανάπτυξη του προϊόντος και για την επιλογή της βέλτιστης περίπτωσης μεταξύ διαφόρων υαλοπινάκων για ειδικές κλιματικές συνθήκες. Τέλος, μια τέτοια μεθοδολογία μπορεί να χρησιμοποιηθεί για την καθιέρωση ενεργειακής σήμανσης, ή ενεργειακής ταξινόμησης των παραθύρων, ενώ επιπλέον είναι σύμφωνη με την Ευρωπαϊκή Οδηγία (2002/91/EC) για την ενεργειακή απόδοση των κτηρίων, που απαιτεί πιστοποιητικά ενεργειακής απόδοσης για υφιστάμενα και νέα κτήρια. / In this study, a novel combination of the Life Cycle Assessment (LCA) and the Eco-efficiency analysis has been developed and implemented to evaluate the environmental, energy and cost efficiency potential of an electrochromic (EC) window prototype that aims to be used as an energy saving component in the building. The main objective is to mark out how the proposed method complements the traditional techniques, namely LCA and Eco-efficiency integrating their individual advantages into a more complete and a further more powerful diagnostic tool. The efficiency of the method is demonstrated with implementation to a 40cm x 40cm EC glazing (K-Glass/WO3/polymer electrolyte/V2O5/K-Glass). The whole life cycle of the EC glazing is evaluated by implementing the method of LCA (ISO 14040). In order to measure and report the ecological efficiency, environmental performance indicators were used, based on material and energy balances. The indicators were suitably defined taking into consideration various parameters (control scenario, expected lifetime, climatic type, purchase cost). Significant conclusions can be drawn for the development and the potential applications of the device compared to other commercial fenestration products. The combination of the results leads to significant conclusions for the balance of its properties and possible improvements that can be utilized in decision making for the product design and development and for the selection of an optimum case among various fenestration products for specific areas/climates. Finally, such a methodology can be utilized to establish a system for energy labeling or energy rating of windows and it is in accordance with the European Directive (2002/91/EC) on the energy performance of buildings, which calls for energy performance certificates to be available for new and existing buildings.
118

Ganzheitliche Ansätze und Methoden zur nachhaltigen Neuplanung einer energieeffizienten Fabrik mit besonderem Schwerpunkt auf die Automobilmontage

Imgrund, Christian 17 December 2014 (has links) (PDF)
Die bisherigen Untersuchungen zum Thema Nachhaltigkeit und Energieeffizienz konzentrierten sich nicht auf die speziellen Anforderungen einer Fahrzeugmontage. Bei der Neuplanung einer Fahrzeugmontage spielte bisher die Energieeffizienz ei-ne untergeordnete Rolle. Mit der zunehmenden Bedeutung von Nachhaltigkeit und der Energieeffizienz in Politik und Öffentlichkeit wachsen auch diesbezüglich die Erwartungen an die Automobilindustrie. Aus diesem Grund wurden ganzheitliche Ansätze und Methoden entwickelt, um einen Neubau eines Fahrzeugwerkes, im Speziellen die Fahrzeugmontage, energieeffizient und nachhaltig zu gestalten. Die Nutzung von natürlichen Ressourcen stand hierbei im Vordergrund. Der Einsatz von fossilen Energien sollte hierbei weitestgehend vermieden werden. Beginnend mit der Standortauswahl über die Festlegung der Werksstruktur sowie der Fahr-zeugmontage- und Logistikstruktur wurden hier die wichtigsten Bereiche der Fab-rikplanung abgedeckt. Zusätzlich wurde noch die Gebäudekonstruktion unter den Prämissen der Energieeffizienz untersucht.
119

Discover, model and combine energy leverages for large scale energy efficient infrastructures / Découvrir, modéliser et combiner des leviers énergétiques pour des infrastructures de calculs basse consommation

Rais, Issam 28 September 2018 (has links)
La consommation énergétique de nos entités de calculs à grande échelle est une problématique de plus en plus inquiétante. Il est d'autant plus inquiétant que nous nous dirigeons vers "L'exascale",machine qui calcule 10^18 opérations flottantes par secondes, soit 10 fois plus que les meilleurs machines publiques actuelles. En 2017, les data-center consommaient 7% de la demande globale et étaient responsable de 2% de l’émission globale de CO2. Avec la multiplication actuelle du nombre d'outils connectés par personne, réduire la consommation énergétique des data-centers et supercalculateurs à grande échelle est une problématique cruciale pour construire une société numérique durable.Il est donc urgent de voir la consommation énergétique comme une problématique phare de cescentres. De nombreuses techniques, ici nommé "levier", ont été développées dans le but de réduire la consommation électrique des centres de calculs, à différents niveaux : infrastructure, matériel, intergiciel et applicatif. Bien utiliser ces leviers est donc capitale pour s'approcher de l'efficience énergétique. Un grand nombre de leviers sont disponibles dans ces centres de calculs. Malgré leurs gains potentiels, il peut être compliqué de bien les utiliser mais aussi d'en combiner plusieurs en restant efficace en énergie.Dans cette thèse, nous avons abordé la découverte, compréhension et usage intelligent des leviers disponibles à grande échelle dans ces centres de calculs. Nous avons étudié des leviers de manière indépendante, puis les avons combinés à d'autres leviers afin de proposer une solution générique et dynamique à l'usage combiné des leviers. / Energy consumption is a growing concern on the verge of Exascale computing, a machine reaching 10^18 operations per seconds, 10 times the actual best public supercomputers, it became a crucial focus. Data centers consumed about 7% of total demand of electricity and are responsible of 2% of global carbon emission. With the multiplication of connected devices per person around the world, reducing the energy consumption of large scale computing system is a mandatory step to address in order to build a sustainable digital society.Several techniques, that we call leverage, have been developed in order to lower the electricalconsumption of computing facilities. To face this growing concern many solutions have beendeveloped at multiple levels of computing facilities: infrastructure, hardware, middle-ware, andapplication.It is urgent to embrace energy efficiency as a major concern of our modern computing facilities. Using these leverages is mandatory to better energy efficiency. A lot of leverages are available on large scale computing center. In spite of their potential gains, users and administrators don't fully use them or don't use them at all to better energy efficiency. Although, using these techniques, alone and combined, could be complicated and counter productive if not wisely used.This thesis defines and investigates the discovery, understanding and smart usage of leverages available on a large scale data center or supercomputer. We focus on various single leverages and understand them. We then combine them to other leverages and propose a generic solution to the dynamic usage of combined leverages.
120

Evaluation ex-post de l’efficacité de solutions de rénovation énergétique en résidentiel / Ex-post evaluation of energy efficiency measures for retrofit in residential buildings

Raynaud, Maxime 11 February 2014 (has links)
En France, les rénovations énergétiques en résidentiel, et ceci tout particulièrement pour les maisons individuelles, font peu l'objet après réalisation d'une évaluation ex-post permettant de quantifier la performance atteinte.Cette thèse se propose donc d'effectuer une évaluation ex-post de l'efficacité de solutions de rénovation énergétique en résidentiel, à partir de données (environ 100 cas par échantillon étudié) provenant d'enquêtes menées auprès de ménages, propriétaires occupants de maison individuelle, ayant participé à des opérations de maîtrise de la demande en énergie conduites à l'échelle régionale dans le nord-est et le sud-est de la France. Une approche statistique tant descriptive que de modélisation est principalement employée pour aborder ce travail.Le premier volet de l'évaluation ex-post consiste en une quantification des économies unitaires obtenues associée à un calcul d'incertitude. Pour chacune des opérations, la modélisation statistique de la consommation énergétique après travaux permet l'étude de l'influence des actions elles-mêmes mais aussi de certains facteurs tels que le changement de la gestion du chauffage ou l'utilisation après travaux de la climatisation.Le second volet de cette évaluation ex-post a pour but d'identifier les causes des écarts entre les consommations observées et celles simulées par un modèle de calcul ex-ante (dit d'ingénieur). Ainsi, nous étudions l'évolution des écarts des états avant à après travaux. Tout d'abord, une quantification et une modélisation statistique des écarts en situation avant travaux est réalisée. Puis, les écarts en situation après travaux sont à leur tour quantifiés et modélisés statistiquement en intégrant notamment l'erreur commise initialement (avant travaux). Les différences entre économies d'énergie observées et simulées sont également étudiées.Enfin, dans la dernière partie de la thèse, sur la base des sources d'écart identifiées, nous proposons des pistes de perfectionnement du modèle de calcul d'ingénieur utilisé. Plus largement, à partir d'un retour critique quant aux limites des modèles statistiques établis pour étudier les causes des écarts, des pistes sont avancées pour permettre de les améliorer. / In France, ex-post evaluations of energy retrofits in residential buildings, allowing to quantify the performance achieved, are rarely realized, particularly for the dwelling houses.This thesis is an ex-post evaluation of energy efficiency measures for retrofit in residential buildings from surveys data (around 100 cases by studied sample) of households, house owners, that participated in regional energy efficiency operations (northeast and southeast of France). This work is mainly tackled by descriptive statistics and statistical models.The first part of the ex-post evaluation is a quantification of unitary energy savings associated to an uncertainty assessment. For the two operations, a statistical model of energy consumption after retrofitting studies the effect of energy efficiency measures and also the effects of factors as space heating management modification or air conditioning use after refurbishment.The second part of the ex-post evaluation has for aim to identify the sources of gaps between observed consumptions and ones simulated by an ex-ante engineering model. Thus, we study gaps evolution from before retrofitting to after retrofitting situations. In the first time, we realise a quantification and a statistical modelling of gaps before retrofitting. Then, we repeat the method for gaps after retrofitting, in taking into account gap before retrofitting in the statistical model. Deviations between observed energy savings and calculated ones are also studied.In the last part of the thesis, we propose some improvements of the engineering model on the base of the gaps sources identified. From a critical analysis of statistical models realised to study gaps, some propositions are did to improve them.

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