Although traditionally Wireless Sensor Network (WSNs) have been regarded as static sensor arrays used mainly for environmental monitoring, recently, its applications have undergone a paradigm shift from static to more dynamic environments, where nodes are attached to moving objects, people or animals. Applications that use WSNs in motion are broad, ranging from transport and logistics to animal monitoring, health care and military. These application domains have a number of characteristics that challenge the algorithmic design of WSNs. Firstly, mobility has a negative effect on the quality of the wireless communication and the performance of networking protocols. Nevertheless, it has been shown that mobility can enhance the functionality of the network by exploiting the movement patterns of mobile objects. Secondly, the heterogeneity of devices in a WSN has to be taken into account for increasing the network performance and lifetime. Thirdly, the WSN services should ideally assist the user in an unobtrusive and transparent way. Fourthly, energy-efficiency and scalability are of primary importance to prevent the network performance degradation. This thesis contributes toward the design of a new hybrid optimization algorithm; ENAMS (Energy optimizatioN Algorithm for Mobile Sensor networks) which is based on the Evolutionary Computation and Swarm Intelligence to increase the life time of mobile wireless sensor networks. The presented algorithm is suitable for large scale mobile sensor networks and provides a robust and energy- efficient communication mechanism by dividing the sensor-nodes into clusters, where the number of clusters is not predefined and the sensors within each cluster are not necessary to be distributed in the same density. The presented algorithm enables the sensor nodes to move as swarms within the search space while keeping optimum distances between the sensors. To verify the objectives of the proposed algorithm, the LEGO-NXT MIND-STORMS robots are used to act as particles in a moving swarm keeping the optimum distances while tracking each other within the permitted distance range in the search space.

Les phénomènes thermoélectriques sont un moyen de convertir directement l’énergie thermique en énergie électrique ; ils sont à ce titre au cœur de nombreuses recherches dans le domaine de l’énergétique. Au-delà de l’optimisation des matériaux constituants les générateurs thermoélectriques, il est également nécessaire de mener une réflexion sur la manière dont ces générateurs sont utilisés. La contribution des contacts thermiques entre le générateur et les réservoirs thermiques est un facteur qui va modifier les conditions de fonctionnement optimales du générateur. En utilisant la notion de courant thermique convectif, développée par Thomson il y a plus de 150 ans, nous généralisons les expressions classiques du fonctionnement à puissance maximum pour le générateur pour ce cas de figure. Nous constatons toutefois que ces conditions se réduisent à une adaptation d’impédance, à la fois thermique et électrique Outre son intérêt pratique, le générateur thermoélectrique est également un système modèle de choix pour étudier la théorie du transport couplé et des phénomènes irréversibles. En utilisant la description donnée par Ioffe de ce système, nous montrons que l’efficacité à maximum de puissance, un coefficient de performance au cœur de la thermodynamique à temps fini, s’exprime comme une fonction relativement simple des paramètres du système. La nouveauté de ce travail repose sur une prise en compte appropriée des dissipations internes associées au processus de conversion d’énergie. Les résultats sont généralisés enfin aux cas d’autres machines thermiques telle que la roue à rochet de Feynman. / Thermoelectric phenomena are a way to directly convert thermal energy into electrical energy; they thus are at the heart of several researches in the field of energy conversion. The optimization of the thermoelectric generators includes materials improvement but a reflection on their working conditions is also mandatory. The contribution of the thermal contacts between the generator and the heat reservoirs is a factor that will change the optimum operating conditions of the generator. Using the concept of convective heat flow, developed by Thomson more than 150 years ago, we generalize the classical expression of maximum power conditions. Moreover, we note that these conditions may be reduced to impedance matching conditions, both thermal and electrical. In addition to its practical interest, the thermoelectric generator is also an ideal model system to study the theory of coupled transport and of irreversible phenomena. Using the description of this system given by Ioffe, we show that the maximum power efficiency, a coefficient of performance at the heart of finite time thermodynamics, expressed as a simple function of the system parameters. The novelty of this work is based on a proper consideration of internal dissipation associated with the energy conversion process. The results are then generalized to other thermal engines such as the Feynman ratchet.

A method for improving performance/watt of an embedded single-instruction multiple-data (SIMD) architecture using application-guided a priori scheduling of hardware resources is presented. A multi-core architectural simulator is adopted that accurately estimates power, performance, and utilization of various processor components (logic, interconnect and memory). A greedy search is then performed on each algorithm block of a signal processing chain in order to schedule each component's throughput and power. The proposed software-directed hardware rebalancing, applied to a typical electroencephalography (EEG) filtering chain, is analyzed for two different SIMD architectures. The first, representing a super V[subscript th] processor demonstrates a 51%-86% improvement in performance/watt at 1%-10% throughput reduction using block level or algorithm level a priori scheduling. The second architecture used is Synctium, a near V[subscript th] processor which demonstrates 50%-99% performance/watt improvement across the same throughput reduction range and optimization techniques. / Graduation date: 2012

This diploma thesis deals with trading of electricity in the current conditions of the Czech Republic. First it defines the theoretical and legal aspects of the electricity market and introduces several basic terms related to the given topic such as producer, electricity dealer, end user etc. Then it analyses selected areas of an electricity dealer’s activities directed at optimization of his/her business strategy concerning electrical energy trading in the current conditions of the Czech energy market.

I detta examensarbete har syftet varit att undersöka hur man kan minska behovet av att behöva köpa energi till en fastighet med tillhörande byggnader. Fokus har legat på att producera nog med energi för att täcka fastighetsägarnas konsumtion av el. Projektet har även berört energioptimeringsåtgärder av enklare slag. Efter detta gjordes en fysisk genomgång av byggnaderna där mätning också genomfördes dels som underlag för en energibalans, dels som underlag när det undersöktes vilka energisparåtgärder som var ekonomiskt genomförbara, såsom tillläggsisolering av vinden. Sedan samlades det in offerter och annan viktig information, såsom energiproduktion och priser, för att sedan analyseras. Alla delar jämfördes och ställdes mot varandra för att komma fram till det som passade fastighetsägarna bäst. Lagring och vindkraft hade en för lång återbetalningstid gentemot vad ägarna hade efterfrågat då de ville att det skulle vara återbetalat innan produkternas livslängd var slut. Resultatet av vindkraften visade att vindhastigheterna inte kunde fastställas helt eftersom den vindmätning som gjorts har skett 25 km därifrån, vilket leder till en osäkerhet i hur mycket el som kan produceras. Det mest lönsamma var den största av de fyra solcellsparker som jämfördes. Den och det lilla vindkraftverket tillsammans producerar tillräckligt mycket el för att täcka deras behov. Däremot rekommenderades varken vindkraftverket eller batterilagring på grund av återbetalningstiden. Ägarna kan alltså producera den mesta elen med hjälp av solceller, dock inte allt enligt de beräkningar som gjorts. Förutom Vattenfalls solceller rekommenderades att tilläggsisolera vinden samt en laddbox från Vattenfall. Eftersom teorin i examensarbetet skulle baseras på granskade källor och inte på vinstdrivande källor användes studentlitteratur, publicerade rapporter och rapporter från myndigheter. / The purpose of this thesis has been to examine how to reduce the need to buy energy for a property with associated buildings. The focus has been on producing enough energy to cover the property owners' consumption of electricity. The project has also involved simpler energy optimization measures. After this, a physical review of the buildings was carried out, where measurement was also carried out partly as a basis for an energy balance and partly as a basis when examining which energy saving measures were economically feasible, such as additional insulation of the wind. Then quotes and other important information, such as energy production and prices, were collected and then analyzed. All parts were compared to each other to arrive at what best suited the property owners. Storage and wind power had too long a payback period against what the owners had asked for when they wanted it to be repaid before the end of product life. The result of the wind power showed that the wind speeds could not be fully determined since the wind measurement made was 25 km away, which leads to an uncertainty in how much electricity can be produced. The most profitable was the largest of the four solar cell parks compared. It and the small wind turbine together produce enough electricity to meet their needs. However, neither the wind turbine nor the battery storage was recommended because of the payback time. The owners can thus produce most of the electricity using solar cells, but not all according to the calculations made. In addition to Vattenfall's solar cells, it was recommended to insulate the wind and install a charging box from Vattenfall. Since the theory in the degree project should be based on audited sources and not on profit-making sources, student literature, published reports and reports from authorities were used.

The world is experiencing increasing energy usage owing to environmental impacts suchas climate change, Ozone layer depletion, and global warming. Energy usage is primarily categorized into transport, industrial, residential, and service sectors, with the transportation and industrial sectors taking up a considerable chunk of the energy use; Buildings partly determine the use of energy globally. This review presents a critical analysis of energy demand and uses in the building sector considering the energy optimization for The Church of Jesus Christ of Latter-day Saints in Trollhättan, including the local energy requirements. The modelling software IDA-ICE isused to conduct simulations for different scenarios. The IDA-ICE software links the actual building images with the isometric views done on a computer. The energy balance of buildings is considered with respect to the three methods for heat transfer, the U-value,ventilation, heating load, and cooling load. The study results show that the building relieson electricity and fuel for its energy supply and that fuel consumption takes the highest share, 60 %. Retrofit 1 (where the oil and electric boilers are replaced by geothermal heat pump with COP 4 for heating and domestic hot water), Retrofit 2 (which keeps changes from Retrofit_1 and where a new AHU with a VAV system replaces the existing two AHUs), and Retrofit 3 (which keeps changes from Retrofit_2 and only connects the heating system to district heating) are designed as part of the findings to understand the variation sin comfort reference, supplied Energy, used Energy, utilized Energy, auxiliary Energy, and the Energy of all zones during heating and cooling. The model results indicate that Retrofit2 demonstrates better results than the other two since it has a higher energy-saving capacity. The energy reduction for Retrofit model 1 is about 33.4 %, while Retrofit model 2 has 55% and model 3 has 33%, significantly decreasing the associated costs. The LCC analysis shows payback for the first model 6.73 years with an investment cost of 700 000 SEK, the second model has 5.84 with 1 million SEK investment, and the third model has 3.4 years with 350 000 SEK.

Energy consumption has become one of the main design constraints in today’s integrated circuits. Techniques for energy optimization, from circuit-level up to system-level, have been intensively researched. The advent of large-scale integration with deep sub-micron technologies has led to both high power densities and high chip working temperatures. At the same time, leakage power is becoming the dominant power consumption source of circuits, due to continuously lowered threshold voltages, as technology scales. In this context, temperature is an important parameter. One aspect, of particular interest for this thesis, is the strong inter-dependency between leakage and temperature. Apart  from leakage power, temperature also has an important impact on circuit delay and, implicitly, on the frequency, mainly through its influence on carrier mobility and threshold voltage. For power-aware design techniques, temperature has become a major factor to be considered. In this thesis, we address the issue of system-level energy optimization for real-time embedded systems taking temperature aspects into consideration. We have investigated two problems in this thesis: (1) Energy optimization via temperature-aware dynamic voltage/frequency scaling (DVFS). (2) Energy optimization through temperature-aware idle time (or slack) distribution (ITD). For the above two problems, we have proposed off-line techniques where only static slack is considered. To further improve energy efficiency, we have also proposed online techniques, which make use of both static and dynamic slack. Experimental results have demonstrated that considerable improvement of the energy efficiency can be achieved by applying our temperature-aware optimization techniques. Another contribution of this thesis is an analytical temperature analysis approach which is both accurate and sufficiently fast to be used inside an energy optimization loop.

Decisions made at the early stage of building and settlement design can greatly influence the energy performance of the built environment. However, the type of feasible design intervention and their impact strong depends on project: if it is a new development or a re-development, whether the setting of the project is urban or rural, etc. Utilizing Bysjöstrand EcoVillage as a case, the aim of this thesis is to improve the energy performance of a new development at its early design stage through the passive and active use of solar energy. The study evaluated the energy saving potential of various passive solar design strategies as well as the solar energy potential of the new development. The steps taken to reduce the energy consumption are focused on the annual heating demand of buildings, since it accounts for more than a half of the total energy consumed by the village. The energy saving potential of the following passive solar design approaches were considered: building siting, building orientation, windows-to-wall ratio (WWR) analysis and insulation thickness optimization from the economic perspective. Furthermore, an assessment of energy generation potential from on-site photovoltaic (PV) systems was conducted. The financial viability of each building’s PV system was also conducted. According to the results, the evaluated passive solar design strategies can reduce the annual heating energy consumption close to 17 %. Regarding onsite energy generation, electricity from roof-installed PV systems can cover over 100% of the annual energy consumption estimated for the residential lighting and equipment within the eco-village. In summary, this study has demonstrated that with the above design considerations a 50 % reduction of energy consumption from the utility grid is possible. This study is useful for architects, energy engineers, and other parties who are involved in residential buildings energy performance optimization.

Decisions made at the early stage of building and settlement design can greatly influence the energy performance of the built environment. However, the type of feasible design intervention and their impact strong depends on project: if it is a new development or a re-development, whether the setting of the project is urban or rural, etc. Utilizing Bysjöstrand EcoVillage as a case, the aim of this thesis is to improve the energy performance of a new development at its early design stage through the passive and active use of solar energy. The study evaluated the energy saving potential of various passive solar design strategies as well as the solar energy potential of the new development. The steps taken to reduce the energy consumption are focused on the annual heating demand of buildings, since it accounts for more than a half of the total energy consumed by the village. The energy saving potential of the following passive solar design approaches were considered: building siting, building orientation, windows-to-wall ratio (WWR) analysis and insulation thickness optimization from the economic perspective. Furthermore, an assessment of energy generation potential from on-site photovoltaic (PV) systems was conducted. The financial viability of each building’s PV system was also conducted. According to the results, the evaluated passive solar design strategies can reduce the annual heating energy consumption close to 17 %. Regarding onsite energy generation, electricity from roof-installed PV systems can cover over 100% of the annual energy consumption estimated for the residential lighting and equipment within the eco-village. In summary, this study has demonstrated that with the above design considerations a 50 % reduction of energy consumption from the utility grid is possible. This study is useful for architects, energy engineers, and other parties who are involved in residential buildings energy performance optimization.

The society is going through transformations in several dimensions at the same time. The energy system is moving towards renewables and reduced resource intensity. Market structures are gradually changing, and new actors emerge to compete with incumbents. Digitization creates fundamentally new conditions for everyone. Cities are being reimagined and are driving much of the transformation. Energy optimization becomes a heated topic for the whole society. This thesis research collaborated with the company SWECO Energy Strategies group investigates one part of energy optimization: proposing different possible scenarios of combining different types of buildings in a city block to urban designers and real estate company. The objective of this research is to find out the suitable combinations leading to an evener and lower demand profile from the perspectives of energy supply and the grid. This thesis project will try different methods to identify the most promising combination of various functioned buildings and develop a new methodology to solve the similar cases. A city block with either several types of building or single type of building can have an even and low energy profile. Moreover, there isn’t a definite relationship between the flatness of energy profile and the correlated amount of total demand. In this project, different scenarios are created and tested by the assistance of Python programing language and Solver installed in Excel. Through a series of tests and analysis, the best case is found with the most area of residential buildings. Qualitatively economic analysis is done, proving that an even energy profile is conducive to the cost-saving. Through the conducted case study, a general methodology is developed, which facilitates urban designers to design similar projects to some extent in the future.