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One of the most complex and urgent challenges in the energy transition is the large-scale refurbishment of the existing housing stock in the built environment. In order to comply with the goals of the Paris convention, the aim is to live “energy-neutral,” that is, a dwelling should produce as much sustainable energy as it consumes on a yearly basis. This means that millions of existing houses need to undergo a radical energy retrofit. In the next 30 years, all dwellings should be upgraded to nearly zero-energy buildings, which is a challenge to accomplish for a reasonable price. Across the EU, many projects have developed successful approaches to the improvement of building technologies and processes, as well a better involvement of citizens. It is important to compare and contrast such approaches and disseminate lessons learned. In practice, it is crucial to raise the level of participation of inhabitants in neighborhood renovation activities. Therefore, the central question of this issue is: How can we increase the involvement of tenants and homeowners into this radical energy renovation?

GECCO 2021, Genetic and Evolutionary Computation Conference Companion, Lille , FRANCE, 10-/07/2021 - 14/07/2021; Traffic perturbations in railway systems may give rise to conflicts, which cause delays w.r.t. the timetable. Dealing with them requires solving the real-time Rail Traffic Management Problem (rtRTMP). A subproblem of the rtRTMP is the real-time Energy Consumption Minimization Problem (rtECMP). It defines the speed profiles along with the timing of multiple trains in a given network and time horizon. It takes as input the train routing and precedences computed by a rtRTMP solver and its objective is to minimize the weighted sum of train energy consumption and total delay. In this paper, we propose an Ant Colony Optimization algorithm for the rtECMP and we test it on the French Pierrefitte-Gonesse control area with dense mixed traffic. The results show that, in 30 seconds, a remarkable exploration of the search space is performed before convergence.

We analyze whether lower rents for energy-inefficient apartments reflect tenants’ willingness to pay due to a higher green awareness, purchasing power, or energy consumption costs. Based on a German rental apartment dataset from Q1 2007 to Q1 2019, we use interaction terms for socioeconomic characteristics in a hedonic regression model. We find that rents are lower for apartments with higher energy consumption, even in neighborhoods with lower levels of green awareness. This relationship is stronger in neighborhoods with higher purchasing power, such that communities with low levels of green awareness and high purchasing power show the steepest negative slope for increasing energy consumption (−8.6% from the highest to lowest rating). Thus, the rent-decreasing effect of purchasing power is higher than that of green awareness. Splitting the entire period into smaller windows, we find that the interaction effect of green awareness has emerged in the most recent years (2017–2019). This may be driven by changes in regulation, which have made it easier for tenants to assess the energy consumption before they rent, or by a general increase in green awareness over this period.

Driven by both regulatory and monetary interests the development of energy monitoring systems has been accelerated in recent years. Thus, a large amount of data is collected and stored in huge databases. This is a decisive step towards sustainable production systems since you can’t improve what you don’t know. This paper aims to use the datasets currently available and to combine databases to gather additional information on production systems, in particular energy flows. Therefore, an algorithm has been developed that combines energy consumption data from production lines with production information to estimate the consumption of connected subsystems. This paper analyzes the algorithm with case studies from companies with their specific databases and will show a deviation of less than 5 % of accumulated energy. Hence, the algorithm is able to create a more detailed analysis of production systems without additional sensor installations by combining existing databases.

Durch den weltweit stetig steigenden Energiebedarf ist die Reduktion des Energieverbrauchs eine wichtige Aufgabe vieler Unternehmen, um langfristig nachhaltig wirtschaften zu können. Das Ziel der vorliegenden Bachelorarbeit ist es zu berechnen, wie sich mobiles Arbeiten auf den Energiebedarf des Bürogebäudes eines IT-Unternehmens auswirkt. Um die Forschungsfrage zu beantworten werden anhand der Berechnung unterschiedlicher Prozentsätze an mobil arbeitenden Mitarbeiterinnen und Mitarbeiter die Auswirkungen auf den Energiebedarf untersucht. Die Grundlage dieser Arbeit bilden sowohl die Daten einer Studie der österreichischen Gesellschaft für Umwelt und Technik als auch interne Informationen des untersuchten Unternehmens. Durch die Berechnungen unter Berücksichtigung der variablen als auch fixen Energieverbrauchsfaktoren konnte festgestellt werden, dass der Energieverbrauch nur dann maßgeblich sinkt, wenn im Zuge der erhöhten mobilen Arbeit auch die Bürofläche des Unternehmens reduziert wird. Due to the constantly increasing worldwide energy demand, reducing energy consumption is an important task for many companies in order to operate sustainably in the long term. The aim of this bachelor thesis is to calculate how mobile working affects the energy consumption of an IT company’s office building. In order to answer the research question, the effects on energy requirements are examined on the basis of the calculation of different percentages of employees working mobile. This work is based on data sourced from a study by the Austrian Society for Environment and Technology as well as internal information provided by the analyzed company. The calculations, taking into account both the variable and fixed energy consumption factors, showed that the energy consumption only drops significantly if the company's office space is also reduced in the course of increased mobile work.

Die vorliegende Arbeit verfolgt die Zielsetzung, den Beitrag verschiedener politischer Handlungsoptionen zur Steigerung der betrieblichen Energieeffizienz zu ermitteln. Eingangs wird aufgezeigt, inwieweit die Steigerung der Energieeffizienz aufgrund ihrer vielfältigen Vorteile eine Einstufung als eigenständige Zielgröße rechtfertigt im Gegensatz zu einer bloßen Betrachtung als Mittel zum Zweck des Klimaschutzes. Für die anschließende quantitative Analyse wurden Daten aus dem Projekt Energieeffizienz Impulsgespräche des Rationalisierungs- und Innovationszentrums der Deutschen Wirtschaft (RKW) e.V. aus den Jahren 2011 bis 2013 mit eigens für diese Arbeit erhobenen Daten von 2017 für dieselben Unternehmen verglichen. Zu diesem Zweck wird ein difference-in-differences-Ansatz genutzt. Im Ergebnis erweisen sich Preise im Gegensatz zu anderen Maßnahmen wie Energieberatungen, Fördermitteln und Energiemanagementsystemen als zumindest teilweise wirksame Einflussgröße für die Energieeffizienz. Der Autor empfiehlt auf dieser Basis eine stärker marktwirtschaftlich ausgerichtete Effizienzpolitik. The purpose of the present thesis is to find out which political instruments like subsidized and obligatory energy consultings, grants for more efficient plants or higher prices have an impact on the energy efficiency of companies. The study is based on an analysis of the question if and why energy efficiency should be considered as an independent goal as opposed to a classification as a means to the end of climate protection. For the subsequent quantitative analysis, data from the project 'Energieeffizienz Impulsgespräche' of the Rationalisierungs- und Innovationszentrum der Deutschen Wirtschaft (RKW) e.V. for the period between 2011 and 2013 is used and compared with newly generated data from 2017 for the same enterprises. For this purpose, a difference-in-differences-approach is used. The results show that while other variables - with the exception of the total volume of sales - don't improve energy efficiency at all or at least not significantly, prices at least partly show a positive impact on energy efficiency. As a consequence, the author is recommending a stronger focus on market-based instruments in energy efficiency politics.

To ensure both good data center service performance and reasonable power consumption, a detailed analysis of the behavior of these systems is essential for the design of efficient optimization algorithms to reduce energy consumption. This thesis fits into this context, and our main work is to design dynamic energy management systems based on stochastic models of controlled queues. The goal is to search for optimal control policies for data center management, which should meet the growing demands of reducing energy consumption and digital pollution while maintaining quality of service. We first focused on the modeling of dynamic energy management by a stochastic model for a homogeneous data center, mainly to study some structural properties of the optimal strategy, such as monotony. Afterwards, since data centers have a significant level of server heterogeneity in terms of energy consumption and service rates, we have generalized the homogeneous model to a heterogeneous model. In addition, since the data center server's wake-up and shutdown are not instantaneous and a server requires a little more time to go from sleep mode to ready-to-work mode, we have extended the model to the purpose of including this server time latency. Throughout this exact optimization, arrivals and service rates are specified with histograms that can be obtained from actual traces, empirical data, or traffic measurements. We have shown that the size of the MDP model is very large and leads to the problem of the explosion of state space and a large computation time. Thus, we have shown that optimal optimization requiring a MDP is often difficult or almost impossible to apply for large data centers. Especially if we take into account real aspects such as server heterogeneity or latency. So, we have suggested what we call the greedy-window algorithm that allows to find a sub-optimal strategy better than that produced when considering a special mechanism like threshold approaches. And more importantly, unlike the MDP approach, this algorithm does not require the complete construction of the structure that encodes all possible strategies. Thus, this algorithm gives a strategy very close to the optimal strategy with very low space-time complexities. This makes this solution practical, scalable, dynamic and can be put online., Pour garantir à la fois une bonne performance des services offerts par des centres de données, et une consommation énergétique raisonnable, une analyse détaillée du comportement de ces systèmes est essentielle pour la conception d'algorithmes d'optimisation efficaces permettant de réduire la consommation énergétique. Cette thèse, s'inscrit dans ce contexte, et notre travail principal consiste à concevoir des systèmes de gestion dynamique de l'énergie basés sur des modèles stochastiques de files d'attente contrôlées. Le but est de rechercher les politiques de contrôle optimales afin de les appliquer sur des centres de données, ce qui devrait répondre aux demandes croissantes de réduction de la consommation énergétique et de la pollution numérique tout en préservant la qualité de service. Nous nous sommes intéressés d’abord à la modélisation de la gestion dynamique de l’énergie par un modèle stochastique pour un centre de données homogène, principalement pour étudier certaines propriétés structurelles de la stratégie optimale, telle que la monotonie. Après, comme des centres de données présentent un niveau non négligeable d'hétérogénéité de serveurs en termes de consommation d'énergie et de taux de service, nous avons généralisé le modèle homogène à un modèle hétérogène. De plus, comme le réveil (resp. l'arrêt) d’un serveur de centre de données n’est pas instantané et nécessite un peu plus de temps pour passer du mode veille au mode prêt à fonctionner, nous avons étendu le modèle dans le but d'inclure cette latence temporelle des serveurs. Tout au long de cette optimisation exacte, les arrivées et les taux de service sont spécifiés avec des histogrammes pouvant être obtenus à partir de traces réelles, de données empiriques ou de mesures de trafic entrant. Nous avons montré que la taille du modèle MDP est très grande et conduit au problème de l’explosion d’espace d'états et à un temps de calcul important. Ainsi, nous avons montré que l'optimisation optimale nécessitant le passage par un MDP est souvent difficile, voire pratiquement impossible pour les grands centres de données. Surtout si nous prenons en compte des aspects réels tels que l'hétérogénéité ou la latence des serveurs. Alors, nous avons suggéré ce que nous appelons l’algorithme greedy-window qui permet de trouver une stratégie sous-optimale meilleure que celle produite lorsqu’on envisage un mécanisme spécial comme les approches à seuil. Et plus important encore, contrairement à l’approche MDP, cet algorithme n’exige pas la construction complète de la structure qui encode toutes les stratégies possibles. Ainsi, cette algorithme donne une stratégie très proche de la stratégie optimale avec des complexités spatio-temporelles très faibles. Cela rend cette solution pratique, évolutive, dynamique et peut être mise en ligne.

This dissertation explores energy transition from a philosophical perspective. It puts forward the thesis that energy production and consumption are so intimately intertwined with society that the transition towards a sustainable alternative will involve more than simply implementing novel technologies. Fossil energy sources and a growth-based economy have resulted in very specific energy practices, which will change in the future. Broader reflection is needed to understand how and in which direction such change is acceptable and desirable. This reflection is initiated by articulating two pertinent problems with current energy practices that have thus far failed to receive appropriate attention in debates on energy transition: 1) the difficulty of dealing with intermittent sources in relation to the idea of cumulative accounting of energy consumption, and 2) the mismatch between expectations of ethical consumer behaviour in energy systems that discourage engagement. To move forward, instead of assuming that all consumption is equivalent and that more is better, we must develop a better informed and more nuanced idea of 'good' energy practices that actually contribute to our quality of life. One often overlooked aspect of this may be 'embodied engagement', which would suggest that automation of tasks through energy-consuming technologies may be convenient, but also tends to lead to a loss of appreciation for both the task and its result. Some things, like creating a cozy environment around a fireplace, or climbing a mountain, are better partly because they take effort. In such cases, the 'efficiency' of the technology (e.g. the heat-pump, or the automobile) is besides the point - the question is whether it gives us anything of value at all.

this paper, an energy consumption model is developed and exploited to evaluate the electrical energy consumption of ultra-wideband impulse radio (UWB-IR) systems. We develop the energy consumption models and our comparative study, on the one hand, for a system based single-input singleoutput (SISO) configuration and a multiple-input single-output (MISO) and, on the other hand, for a time reversal TR-MISO configuration and for MISO alone configuration. We consider an indoor propagation environment based on the 802.15.4a channel model. The results show very different behaviors depending on the propagation conditions, the number of antennas used, or on the number of transmitted symbols. Using such a model, a radiofrequency designer can obtain significant inputs to optimally select an adequate configuration to design an adaptive energyaware UWB-IR system.

EWGT 2016 - 19th EURO Working Group on Transportation Meeting, Istanbul, TURQUIE, 05-/09/2016 - 07/09/2016; When train operations are perturbed, a new working timetable needs to be computed in real-time. In the literature, several algorithms have been proposed for optimizing this computation. This optimization usually does not consider energy consumption. However, minimizing energy consumption is a central issue both from the environmental and economic perspective. In this paper, we address the real-time problem of minimizing the energy consumption. The energy consumption depends on driving regimes used by the train drivers. Hence, we focus on the decision of the appropriate driving regimes throughout each train's travel along a given infrastructure. A model and solution approach for this problem are provided. We show a proof of concept on the applicability of this solution approach on a simple test case.

In accordance with the environmental concerns that national policies still address throughout the world, railways have been extensively studied to provide quantified indicators for assessing construction/operations practices. It is essential to take energy consumption, into account since energy can be measured worldwide, in addition to constituting a global environmental load that is time-limited as regards resource availability and known as a discriminating criterion in comparing transport infrastructure. This article introduces an innovative, generic and systemic method dedicated to determining the energy consumption of a railway line during the pre-project phase by taking into account the complete life cycle of the rail infrastructure, including construction, maintenance and operations. The method developed (called ≪PEAM ≫) focuses on assessing project variants during the design stage and therefore integrates both the geometric longitudinal constraints of the line and the thicknesses/volumes over the entire itinerary as design parameters for input into the various construction scenarios. PEAM combines methodologies stemming from life cycle assessment with a consumption model derived from physical modeling. The models associated with this method are then applied to study the energy consumption of a new high-speed line located in France that also has major implications for the European connections currently under investigation as well. Two project variants are compared in terms of total energy for a 50-year service life and a given characteristic rail traffic, including passenger and freight flows. Results obtained reveal a 30% difference between the two variants, which prior to applying PEAM were considered to be relatively similar.

ICMLA 2016 - IEEE 15th International Conference on Machine Learning and Applications, Anaheim , ETATS-UNIS, 18-/12/2016 - 20/12/2016; In recent years, many research studies are conducted into the use of smart meters data for developing decision-making tools including both analytical, forecasting and display purposes. Forecasting energy generation or forecasting energy consumption demand are indeed central problems for urban stakeholders (electricity companies and urban planners). These issues are helpful to allow them ensuring an efficient planning and optimization of energy resources. This paper investigates the problem for forecasting the hourly solar irradiance within a Machine Learning (ML) framework using Similarity method (SIM), Support Vector Machine (SVM) and Neural Network (NN). These approaches rely on a methodology which takes into account the previous hours of the predicting day and also the days having the same number of sunshine hours in the history. The study is conducted on a real data set collected on the Paris suburb of Alfortville. A comparison with two time series approaches namely Naive method and Autoregressive Moving Average Model (ARMA) is performed. This study is the first step towards the development of the hourly solar irradiance forecasting hybrid models.

The environment is undergoing a significant damage caused by the use of non-renewable energy sources. The information and communications technology sector is responsible for 2% of the global carbon footprint. Statistics show also that the energy consumed by wireless networks represents around 10% of the annual energy consumption. With the widespread of the Internet of Things, cellular networks are becoming the most used communication technology. Therefore, these networks start using heterogeneous infrastructures to address the lack of capacity.In this thesis, we focus on studying the energy saving problem within cellular networks. In particular, the energy consumed by heterogeneous cellular networks, which are known by their main importance in the future communication architectures namely, 5G networks. Heterogeneous networks (HetNets) use different types of access technologies. In addition to the conventional base stations, these networks introduce the concept of small cells which is characterized by the use of Microcells, Picocells and Femtocells. This diversity offers several advantages in terms of spectral efficiency, network coverage and capacity.; L’environnement subit des dégradations importantes causées par l’utilisation des énergies non renouvelables. Plus particulièrement, le secteur des technologies de l’information et de la communication est responsable de l’émission de 2% du taux mondial de carbone. Les statistiques montrent que l’énergie consommée par les réseaux sans fil constitue 10% de l’énergie globale consommée annuellement. Avec la prolifération des objets connectés, les réseaux cellulaires deviennent le moyen de communication le plus utilisé. De ce fait, ces réseaux commencent à adopter un déploiement hétérogène afin de faire face au manque de capacité dans les infrastructures actuelles.Dans cette thèse, nous nous concentrons principalement sur l’étude de l’économie d’énergie dans les réseaux cellulaires et en particulier, l’énergie consommée par les réseaux cellulaires hétérogènes (Heterogeneous Networks, HetNet), connus pour leur rôle principal dans les futures architectures de communication, à savoir la 5G. Les HetNets se distinguent par l’utilisation de différents moyens et technologies d’accès. En plus des stations de base conventionnelles, ces réseaux introduisent le concept des «Small Cells» qui se caractérise par l’utilisation de Microcells, Picocells et/ou Femtocells. Cette diversité offre plusieurs avantages au niveau de l’efficacité spectrale, de la capacité et de la couverture réseau.

The environment is undergoing a significant damage caused by the use of non-renewable energy sources. The information and communications technology sector is responsible for 2% of the global carbon footprint. Statistics show also that the energy consumed by wireless networks represents around 10% of the annual energy consumption. With the widespread of the Internet of Things, cellular networks are becoming the most used communication technology. Therefore, these networks start using heterogeneous infrastructures to address the lack of capacity.In this thesis, we focus on studying the energy saving problem within cellular networks. In particular, the energy consumed by heterogeneous cellular networks, which are known by their main importance in the future communication architectures namely, 5G networks. Heterogeneous networks (HetNets) use different types of access technologies. In addition to the conventional base stations, these networks introduce the concept of small cells which is characterized by the use of Microcells, Picocells and Femtocells. This diversity offers several advantages in terms of spectral efficiency, network coverage and capacity.; L’environnement subit des dégradations importantes causées par l’utilisation des énergies non renouvelables. Plus particulièrement, le secteur des technologies de l’information et de la communication est responsable de l’émission de 2% du taux mondial de carbone. Les statistiques montrent que l’énergie consommée par les réseaux sans fil constitue 10% de l’énergie globale consommée annuellement. Avec la prolifération des objets connectés, les réseaux cellulaires deviennent le moyen de communication le plus utilisé. De ce fait, ces réseaux commencent à adopter un déploiement hétérogène afin de faire face au manque de capacité dans les infrastructures actuelles.Dans cette thèse, nous nous concentrons principalement sur l’étude de l’économie d’énergie dans les réseaux cellulaires et en particulier, l’énergie consommée par les réseaux cellulaires hétérogènes (Heterogeneous Networks, HetNet), connus pour leur rôle principal dans les futures architectures de communication, à savoir la 5G. Les HetNets se distinguent par l’utilisation de différents moyens et technologies d’accès. En plus des stations de base conventionnelles, ces réseaux introduisent le concept des «Small Cells» qui se caractérise par l’utilisation de Microcells, Picocells et/ou Femtocells. Cette diversité offre plusieurs avantages au niveau de l’efficacité spectrale, de la capacité et de la couverture réseau.

The environment is undergoing a significant damage caused by the use of non-renewable energy sources. The information and communications technology sector is responsible for 2% of the global carbon footprint. Statistics show also that the energy consumed by wireless networks represents around 10% of the annual energy consumption. With the widespread of the Internet of Things, cellular networks are becoming the most used communication technology. Therefore, these networks start using heterogeneous infrastructures to address the lack of capacity.In this thesis, we focus on studying the energy saving problem within cellular networks. In particular, the energy consumed by heterogeneous cellular networks, which are known by their main importance in the future communication architectures namely, 5G networks. Heterogeneous networks (HetNets) use different types of access technologies. In addition to the conventional base stations, these networks introduce the concept of small cells which is characterized by the use of Microcells, Picocells and Femtocells. This diversity offers several advantages in terms of spectral efficiency, network coverage and capacity.; L’environnement subit des dégradations importantes causées par l’utilisation des énergies non renouvelables. Plus particulièrement, le secteur des technologies de l’information et de la communication est responsable de l’émission de 2% du taux mondial de carbone. Les statistiques montrent que l’énergie consommée par les réseaux sans fil constitue 10% de l’énergie globale consommée annuellement. Avec la prolifération des objets connectés, les réseaux cellulaires deviennent le moyen de communication le plus utilisé. De ce fait, ces réseaux commencent à adopter un déploiement hétérogène afin de faire face au manque de capacité dans les infrastructures actuelles.Dans cette thèse, nous nous concentrons principalement sur l’étude de l’économie d’énergie dans les réseaux cellulaires et en particulier, l’énergie consommée par les réseaux cellulaires hétérogènes (Heterogeneous Networks, HetNet), connus pour leur rôle principal dans les futures architectures de communication, à savoir la 5G. Les HetNets se distinguent par l’utilisation de différents moyens et technologies d’accès. En plus des stations de base conventionnelles, ces réseaux introduisent le concept des «Small Cells» qui se caractérise par l’utilisation de Microcells, Picocells et/ou Femtocells. Cette diversité offre plusieurs avantages au niveau de l’efficacité spectrale, de la capacité et de la couverture réseau.

The development of energy storage solutions is a key challenge to enable the energy transition from fossil resources to renewable energies. The need to store energy actually comes from a dissociation between energy sources and energy demand. Storing energy meets two principal expectations: have energy available where and when it is required. Low temperature heat, for dwellings and offices heating, represents a high share of overall energy consumption (i.e. about 35 %). The development of heat storage solutions is then of great importance for energy management, especially in the context of the growing part of renewable energies. Adsorption heat storage appears to be the best trade off among available storage technologies in terms of heat storage density and performances over several cycles. Then, this PhD thesis focuses on adsorption heat storage and addresses the enhancement of storage performances and system integration. The approach developed to address these issues is numerical. Then, a model of an adsorption heat storage tank is developed, and validated using experimental data. The influence of material thermophysical properties on output power but also on storage density and system autonomy is investigated. This analysis enables a selection of particularly influencing material properties and a better understanding of heat and mass transfers. The influence of operating conditions is also underlined. It shows the importance of inlet humidity on both storage capacity and outlet power and the great influence of discharge flowrate on outlet power. Finally, it is shown heat storage capacity depends on the storage tank volume, while outlet power depends on cross section area and system autonomy on bed length. Besides, the conversion efficiency from absorbed energy (charge) to released energy (discharge) is 70 %. But during the charging process, about 60 % of incoming heat is not absorbed by the material and directly released. The overall conversion efficiency from energy provided to energy released is as low as 25 %. This demonstrates that an adsorption heat storage system cannot be thought of as a self-standing component but must be integrated into the building systems and control strategy. A clever use of heat losses for heating applications (in winter) or inlet fluid preheating (in summer) enhances global performances. Using available solar heat for system preheating is an interesting option since a part is instantly retrieved at the outlet of the storage tank and can be used for direct heating. Another part is stored as sensible heat and can be retrieved a few hours later. At least, it has the advantage of turning the adsorption storage tank into a combined sensible-adsorption storage tank that offers short-term and long-term storage solutions. Then, it may differ avoidable discharges of the sorption potential and increase the overall autonomy (or coverage fraction), in addition to optimizing chances of partial system recharge., Le développement de solutions de stockage de l'énergie est un défi majeur pour permettre la transition énergétique d'un mix énergétique fortement carboné vers une part plus importante des énergies renouvelables. La nécessité de stocker de l'énergie vient de la dissociation, spatiale et temporelle, entre la source et la demande d'énergie. Stocker de l'énergie répond à deux besoins principaux : disposer d'énergie à l'endroit et au moment où on en a besoin. La consommation de chaleur à basse température (pour le chauffage des logements et des bureaux) représente une part importante de la consommation totale d'énergie (environ 35 % en France en 2010). Le développement de solutions de stockage de chaleur est donc d'une grande importance, d'autant plus avec la montée en puissance des énergies renouvelables. Parmi les technologies de stockage envisageables, le stockage par adsorption semble être le meilleur compromis en termes de densité de stockage et de maintient des performances sur plusieurs cycles de charge-décharge. Cette thèse se focalise donc sur le stockage de chaleur par adsorption, et traite de l'amélioration des performances du stockage et de l'intégration du système au bâtiment. L'approche développée pour répondre à ces questions est numérique. L'influence des propriétés thermophysiques de l'adsorbant et du fluide sur la densité de puissance d'une part, mais aussi sur la densité de stockage et l'autonomie du système, est étudiée. L'analyse des résultats permet de sélectionner les propriétés des matériaux les plus influentes et de mieux comprendre les transferts de chaleur et de masse au sein du réacteur. L'influence des conditions opératoires est aussi mise en avant. Enfin, il est montré que la capacité de stockage est linéairement dépendante du volume de matériau, tandis que la puissance dépend de la surface de section et que l'autonomie dépend de la longueur du lit d'adsorbant. Par ailleurs, le rapport entre l'énergie absorbée (charge) et relâchée (décharge) est d'environ 70 %. Mais pendant la phase de charge, environ 60 % de la chaleur entrant dans le réacteur n'est pas absorbée et est directement relâchée à la sortie. La conversion globale entre l'énergie récupérable et l'énergie fournie n'est donc que de 25 %. Cela montre qu'un système de stockage de chaleur par adsorption ne peut pas être pensé comme un système autonome mais doit être intégré aux autres systèmes de chauffage du bâtiment et aux lois de commande qui les régissent. Utiliser la ressource solaire pour le préchauffage du réacteur est une idée intéressante car elle améliore l’efficacité de la charge et permet une réutilisation de la part récupérée en sortie pour le chauffage direct du bâtiment. La part stockée sous forme sensible peut être récupérée plusieurs heures plus tard. Le système est ainsi transformé en un stockage combiné sensible/adsorption, avec une solution pour du stockage à long terme et pour du stockage à court terme.

In Europe, a tax is levied on energy. The taxes levied on the most essential forms of energy in the greenhouse horticulture sector in the countries of north-western Europe have been examined. The greenhouse horticulture sectors in individual countries use various types of fuels, purchase heat and electricity and utilise CHP installations. There are significant differences in the energy taxes of different countries and between the different forms of energy per country. Reduced rates and exemptions for the greenhouse horticultural sector exist in each of the countries that were examined. Generally, the costs of energy tax are the highest in Denmark, followed by the United Kingdom, the Netherlands, Germany, France, Belgium and Poland. In terms of energy taxes, north-western Europe does not offer greenhouse horticultural holdings a level playing field. In Europa wordt belasting geheven op energie. De belastingen voor de belangrijkste energiesoorten inde glastuinbouw in de landen in Noordwest-Europa zijn onderzocht. In de afzonderlijke landen wordendoor de glastuinbouw verschillende brandstoffen ingezet, warmte en elektriciteit ingekocht en wkinstallatiesgebruikt. De energiebelasting vertoont grote verschillen tussen landen en tussenenergiesoorten per land. Verlaagde tarieven of vrijstellingen voor de glastuinbouw zijn er in alleonderzochte landen. In het algemeen zijn de kosten voor energiebelasting het hoogst in Denemarken,gevolgd door het Verenigd Koninkrijk, Nederland, Duitsland, Frankrijk, België en Polen. Bezien vanuitde energiebelasting is er in Noordwest-Europa geen gelijk speelveld voor glastuinbouwbedrijven

In PowerMatching City, the leading Dutch smart grid project, 40 households participated in a field laboratory designed for sustainable living. The participating households were equipped with various decentralized energy sources (PV and micro combined heat-power units), hybrid heat pumps, smart appliances, smart meters, and an in-home display. Stabilization and optimization of the network was realized by trading energy on the market. To reduce peak loads on the smart grid and to be able to make optimal use of the decentralized energy sources, two energy services were developed jointly with the end users: Smart Cost Savings enabled users to keep the costs of energy consumption as low as possible, and Sustainable Together enabled them to become a sustainable community. Furthermore, devices could be controlled automatically, smartly, or manually to optimize the energy use of the households. Quantitative and qualitative studies were conducted to provide insight into the experiences and behaviours of end users. In this chapter, these experiences and behaviours are described. The chapter argues that end users: (1) prefer to consume self-produced energy, even when it is not the most efficient strategy to follow, (2) prefer feedback on costs over feedback on sustainability, and (3) prefer automatic and smart control, even though manual control of appliances felt most rewarding. Furthermore, we found that experiences and behaviours were fully dependent on trust between community members, and on trust in both technology (ICT infrastructure and connected appliances) and the participating parties.

Travel statistics for most countries are subject to numerous uncertainties. But as presented in this paper, the IEA has developed a sufficient database to estimate passenger travel by mode for major countries and regions around the world, and produce consistent travel and energy use estimates, perhaps the first of their kind. For example, we estimate that in 2005 total global passenger travel using motorised modes was about 40 trillion kilometres, or about 6000 per person. The IEA has also developed a set of travel projections to 2050, including a Baseline and a "Modal Shift" scenario. This paper provides the result of this analysis and estimates the potential impacts on CO2 from a 25% reduction in car and air travel by 2050 relative to the Baseline in that year. The modelling effort and policy analysis used to support the findings are also described.

Cette thèse s’intéresse à la consommation énergétique d’un système embarqué durant l’execution d’un programme. Une preuve théorique est présentée dans cette thèse et expérimentale de l’existence d’une loi de convexité énergie-fréquence de la consommation des programmes, qui concerne la consommation d’énergie et la fréquence des microprocesseurs à l’échelle nanométrique. Des noyaux de calcul intensif spécifiques ont été exécutés sur des processeurs d’applications typiques, à l’échelle nanométrique, et leurs caractéristiques mesurées en utilisant des capteurs de puissance à haute résolution. Lesdonnées recueillies lors de nombreuses campagnes d’acquisition de données longues de plusieurs semaines chacune suggèrent que la consommation est fortement corrélée avec la fréquence du microprocesseur et, ce qui est extrêmement intéressant, que la courbe présente un minimum clair sur la gamme de fréquences utilisables sur les processeurs.Un modèle analytique de ce comportement est fourni et motivé; il cadre particulièrement bien avec les données. Les circonstances dans lesquelles cette règle de convexité peut être exploitée sont discutées, en particulier dans le but d’améliorer l’efficacité énergétique du microprocesseur. La loi de convexité énergie-fréquence de la consommation des programmesest potentiellement plus exploitable par les systèmes de faible puissance, tels que les systèmes embarqués et alimentés par piles ou batteries, et moins susceptible de l’être par les systèmes informatiques de haute performance. La loi de convexité énergiefréequence de la consommation des programmes est également appliquée aux systèmes multi-coeurs, à la loi d’Amdahl et aux systèmes informatiques hétérogènes.Etant donné que la consommation d’énergie du microprocesseur dépend de sa température, une relation température/puissance au niveau macro pour les processeurs d’application est également introduite et validée expérimentalement dans cette thèse. En adoptant une vision holistique, ce modèle est capable de prendre en compte de nombreux effets physiques qui se produisent dans de tels systèmes. Via des mesures sur deux platesformes pertinentes comportant des processeurs d’applications à l’échelle nanométrique, il est montré que la relation puissance/température se comporte de manière exponentielle entre 20C et 85C.Les données suggèrent de plus que, pour une plage de températures comprise entre 20C et 55C, un modèle quadratique est toujours suffisamment précis et qu’une approximation linéaire est même acceptable. Des modèles de transformationd’énergie visant à annuler les biais liés à la température dans les mesures de puissance sont également présentés.Ces modèles de transformation ont été mis au point afin d’augmenter la précision et la pertinence des traces de mesure de puissance.Outre les mesures statiques de puissance, les comportements transitoires en puissance et température sont également analysés à l’aide des lois de refroidissement et des modèles température/puissance. Il s’avère que des modèles de refroidissement exponentiels sont justifiés pour des microprocesseurs refroidis de manière active. Cependant, pour les processeursrefroidis passivement que l’on trouve fréquemment dans les systèmes embarqués, une loi exponentielle ne peut pas être justifiée théoriquement. En conséquence, la loi ex-acte de refroidissement pour un corps à refroidissement passif est analysée, sous condition de refroidissement radiatif et d’un niveau modeste de perte de chaleur par convection.Si l’on se concentre sur les microprocesseurs embarqués, il y a une différence de performance entre la nouvelle loi de refroidissement passif et celle, exponentielle, classiquement utilisée. On montre que, pour les grandes surfaces, le refroidissement par rayonnement peut être comparable à celui lié à la convection. Toutefois, pour les grandes surfaces derefroidissement de l’ordre de 1dm2 ou plus, les différences entre la loi de refroidissement passif et la loi exponentielle de refroidissement sont importantes. Ces résultats suggèrent donc que, en l’absence de mesures précises de la température, une loi exponentielle de refroidissement n’est suffisamment précise que pour les petits systèmes SoC ne nécessitant qu’une faible charge de traitement.; Both theoretical and experimental evidence is presented in this work for the existence of an Energy/Frequency Convexity Rule, which relates energy consumption and microprocessor frequency for nanometer-scale microprocessors. Typical nanometer-scale application processorswere monitored running specific compute-intensive kernels using high-resolution power gauges. Data gathered during several week-long acquisition campaigns suggest that energy consumed is strongly correlated with the microprocessor’s frequency, and, more interestingly, the curve exhibits a clear minimum over the processor’s frequency range. An analytical model for this behavior is provide and motivated, which fits well with the data.The circumstances are discussed under which this convexity rule can be exploited, and when other methods are more effective, with the aim of improving the microprocessor’s energy efficiency. The Energy/Frequency Convexity Rule is potentially more exploitable by low-power systems, such as battery-powered and embedded systems, and less likely by high-performance computer systems. The Energy/Frequency Convexity Rule is also applied to multi-buddy systems, Amdahl’s law and heterogeneous computing. Given that the microprocessor’s energy consumption is temperature-dependent, a macro-level temperature/power relationship for application processors is introduced and experimentally validated. By adopting a holistic view, this model is able to take into account many of the physical effects that occur within such systems. Via measurements on two pertinent platforms sporting nanometer-scale application processors, it is shown that the power/temperature relationship is indeed very likely exponential over a 20C to 85C temperature range. The data suggest that, for a temperature range between 20C and 55C, a quadratic model is still accurate and a linear approximation is acceptable. Power transformation models are also presented that aim at canceling the temperature biases in power traces. These transformation models are developed to increase the accuracy andmeaningfulness of power measurement traces.Besides static power measurements, the transient power and thermal behavior are also analyzed by means of the cooling laws and the temperature/power relationship models. Exponential cooling models are justified for actively-cooled microprocessors. For passively cooled processors however, as frequently found in embedded systems, an exponential law may not be theoretically justified. Here, the tractability of the exact cooling law fora passively-cooled body is analyzed, subject to radiative cooling and a modest level of heat loss via convection. Focusing then on embedded microprocessors, the performance difference between the new passive cooling law and the conventionally-used exponential one is compared. It is shown that, for large surface sizes, the radiative cooling component can be comparable to the convective cooling one. However, for large cooling surfaceareas of the order of 10 cm2 or more, it is shown that the differences between the passive cooling law and the exponential cooling law are significant. The results thus suggest that, in the absence of accurate temperature measurements, an exponential cooling law is only accurate enough for small-sized SoC systems that require low processing overhead.