The aim of thesis is the energy evaluation of building for public facilities - kindergarten. From the beginning work deals with the analysis of a given topic, standard and legal regulations associated with the topic. This knowledge is further applied to a specific building. It follows by evaluation of the current state of the building, its systems, internal environment and analysis of measures leading to energy savings and ensuring the quality of the indoor environment of building. Work also deals with experimental measurements of selected parameters of the internal environment.

[pt] Um dos principais desafios em redes de sensores sem fio (RSSF) é reduzir o consumo de energia dos nós sensores. Um método usado para economizar a bateria que alimenta os nós sensores é o duty cycling (DC) do rádio, onde o rádio fica desligado na maior parte do tempo e fica ligado por pouco tempo para verificar se existe alguma mensagem. O DC é usado com frequência em aplicações de monitoramento onde apenas uma mensagem é transmitida depois da leitura do sensor. Geralmente a leitura do sensor só volta a acontecer depois de minutos, logo poucas mensagens são transmitidas por unidade de tempo. Neste trabalho, analisamos o uso da técnica de DC em um contexto diferente, o da disseminação de código, onde várias mensagens são enviadas em um curto espaço de tempo, e que usa mensagens broadcast, ao contrário do monitoramento, que utiliza mensagens unicast. Analisamos dois algoritmos de disseminação específicos, um para um ambiente de máquinas virtuais executando nos motes, onde o código disseminado é um script com tamanho da ordem de bytes, e outro para disseminação de códigos da aplicação inteira, onde o tamanho é bem maior que no caso do script, da ordem de kbytes. O objetivo deste trabalho foi avaliar qual o impacto do DC na latência e quanto de energia foi economizado quando comparado a deixar o rádio ligado o tempo todo, que é como ambos algoritmos funcionam em sua forma original. / [en] One of the key challenges in wireless sensor networks (WSN) is to save energy at motes. One method to save battery is radio duty cycling (DC), which keeps the radio turned off in most of the time and turns the radio on for a short time to verify if any there are any messages. DC is frequently used in monitoring applications where only one message is transmitted after the mote reads its sensor. Usually the mote reads its sensor only once every few minutes, so few unicast messages are transmitted in the network per time unit. This work analyzes the use of the DC method in code dissemination. In this context, multiple broadcast messages are transmitted in a short time. We examined two specific dissemination algorithms, one of them proposed for a virtual machine environment, in which the disseminated code is a small script, and a second one originally proposed for disseminating the code of an entire application, typically much larger than a script. The objective of this study is to evaluate the impact of DC on latency and how much energy was saved when compared to leaving the radio on all the time, which is how both algorithms work in their original form.

The current interest in energy saving asphalt production techniques is great and several new processes have been developed to reduce the mixing and compaction temperatures for hot mix asphalt. In particular, mastic asphalt products (Gussasphalt) require high working temperatures, and harder requirements concerning bitumen fumes and carbon dioxide emissions have been introduced for such products. Consequently, the need of a new means of producing and placing mastic asphalt at lower temperatures is particularly large. One way of reducing asphalt mixture temperature is by using special flow improving additives like wax. This technique has successively been tried in several studies for polymer modified mastic asphalt used for bridge decks and parking areas in Sweden. However, there still are uncertainties about possible negative impact on crack susceptibility at lower temperatures due to the addition of wax. In this study, 4% montan wax (Asphaltan A) was used for one particular polymer modified mastic asphalt product. Type and amount of wax additive was selected based on results from earlier studies. The impact on binder, binder/filler mixtures and mastic asphalt from production was tested in the laboratory, focusing on low temperature performance. The bending beam rheometer (BBR) was used for determining low temperature creep compliance and the tensile stress restrained specimen test (TSRST) for determining fracture temperatures. Binder properties were determined using dynamic mechanical analysis (DMA), Fourier transform infrared (FTIR) spectroscopy and conventional tests (softening point, penetration, elastic recovery, Fraass breaking point, viscosity and storage stability). Aging was performed using the rolling thin film oven test (RTFOT) at 200°C. As expected, the addition of wax to the polymer modified binder showed a viscosity reduction at higher temperatures, corresponding to a similar positive effect of more than 10°C on production and laying temperature for the mastic asphalt. DMA and BBR results showed some increase in stiffness and a more elastic response of the wax modified binder at medium and low temperatures. The TSRST fracture temperature was 5 °C higher for the mastic asphalt containing 4% wax, indicating however no dramatic negative impact on crack susceptibility.

As the energy price goes up, more and more concern has been focused on the sustainable development of residential houses. One of the best solution will be the low energy housing-passive house. The concept of passive house has been popular in Germany and whole Europe in the last 10 years, however, there is no official residential passive house standard project in China now. In this thesis, the feasibility of developing passive house in China will be analysed. Combined with the mature experience from the passive house project in Europe, a Chinese way of building the passive house will be provided. According to the previous studies, a lot of knowledge of passive house projects in Sweden have been referred to help doing the analysis about the passive house development in China. Due to the fact that there is no passive house had done before in China, the some assumptions have been made to help with the economy analysis. It is assumed that one passive house residential project will be built in Shenyang city, Liaoning Province. After the analysing and calculating, it can be concluded that it is possible and profitable to develop the passive house standard residential projects in China. It has a bright future.

Legislation, economic incentives and informational campaigns are traditional tools of government used to exert its influence on citizens. More recently, other behavioral interventions called nudges and boosts have also come into usage to influence behavior. Nudges exploit faults in human decision making, pushing the individual in a direction of a specific choice, hence the name nudge. Boosts instead try to foster existing competences in the individual, effectivizing decision making while still preserving the individual’s own agency. Both nudges and boosts have proved to be cost-effective ways of influencing behavior, making them attractive alternatives to traditional behavioral interventions. An a priori way to investigate the effectiveness of behavioral interventions without their implementation is by measuring their acceptance. This thesis investigates the acceptance for nudges and boosts compared to traditional behavioral interventions when used in the domain of energy saving practices. The results show that acceptance differs greatly depending on which behavioral intervention is used, which energy saving domain the behavioral intervention is applied to, and to an extent the demographic characteristics of the individuals exposed to the behavioral intervention.

<p>Most of the heavy-duty machines, in particular construction vehicles, employ hydraulically actuated functions that are used to perform multiple tasks with elevated power requirements. Such high-power demand motivates the Original Equipment Manufacturers (OEMs) to minimize the costs associated with energy consumption through the design of such hydraulic systems. The human-machine interaction (human factors) and the efficiency of the hydraulic control system are considered key elements towards a successful design. The interaction between the operator and the machine considerably affects the performance of construction machines. In order to maintain high levels of productivity, the operators require comfort and effortless controllability of the multiple hydraulic functions. The comfort requirement can include limited shocks and oscillations while operating the machines (while driving and controlling the implement motion), cabin accessories (AC, radio, cameras, etc.) and accessibility to the instrumentation. Besides, the operators have to control multiple functions simultaneously in an efficient manner while maintaining high levels of productivity. Consequently, the operators require smooth controllability of such functions. Such demand can largely affect the efficiency of the expected hydraulic control system and can induce additional costs and complexity. The OEMs are therefore forced to find a balance between efficiency and operators’ requirements to be competitive on the market. As a result, the currently adopted hydraulic architectures rely on purely hydraulic components to ensure robustness and functionality of the hydraulic functions at the expenses of limited performance and high-power consumption. In this dissertation, electro-hydraulic components are employed to induce improvements of the commercially available solutions while still complying with the operators’ demands and energy efficiency. To this end, this work tackles the weaknesses of traditional hydraulic architectures and it proposes alternative solutions to overcome their limitations. Two full-size wheel loaders are used to study the behavior of the existing system and later to implement the proposed variations. First, the development of an innovative ride control feature to improve the operators’ comfort is presented. Experimental results show the proposed strategy having better comfort performances compared to the purely hydraulic solution. Besides, the electro-hydraulic alternative does not demand the costly additional components the commercial solution instead requires. Second, this work faces the concern for efficiency of the present hydraulic architecture. The most diffused hydraulic system for the studied category of construction machines, commonly known as Load Sensing (LS), is sized to work most efficiently for elevated power conditions. During this work, an electronically controlled hydraulic supply unit and a flow-sharing method are used to reduce the hydraulic power consumption in the regions where the traditional LS system is less efficient. With a simple and cost-effective modification, the presented control strategy can induce an efficiency improvement over a wide range of operating conditions. Third, this dissertation proposes an operator-assistance feature to potentially increase the overall productivity and reduce the operator’s stress. An online estimation algorithm was developed to predict the payload weight of the transported material inside the bucket and the pushing forces during a typical loading cycle. The calculated payload mass provides an estimate of the user’s productivity level and it is extremely advantageous when the loaded material should reach a certain target weight. The developed estimation algorithm can also support an optimized autonomous excavation process, which can progressively limit the operator-machine interaction.</p>

Ce travail de thèse traite différents aspects de la conception basse consommation. Tout d’abord, le concept du calcul réversible, considéré comme le premier essai pour un calcul sans dissipation, est présenté. Puis, je me suis intéressée aux dissipations des circuits complémentaires MOS puisque c’est la logique la plus couramment utilisée dans les circuits numériques. J’ai proposé deux approches pour réduire la consommation de ces circuits numériques. La première approche porte sur la réduction de la dissipation due aux glitchs. J’ai proposé une nouvelle méthode qui consiste à adapter les tensions de seuil des transistors pour assurer un filtrage optimal de ces glitchs. Les résultats de simulation montrent que nous obtenons jusqu’à16% de réduction des glitchs, ce qui représente une amélioration de 18% par rapport à l’état de l’art sur la base des circuits de référence ISCAS85. La deuxième approche porte sur la réduction de la dissipation obtenue en faisant fonctionner les transistors MOS en régime d’ inversion faible (sous-seuil). Les circuits fonctionnant dans ce régime représentent une solution idéale pour les applications ultra-basse-consommation. Par contre, l’une des préoccupations majeures est qu’ils sont plus sensibles aux dispersions des processus de fabrication, ce qui peut entraîner des problèmes de fiabilité. Je propose un modèle compact qui détermine le point d’énergie minimum de façon analytique, donc sans recourir à une simulation type SPICE, tout en étant suffisamment précise vis-à-vis de la variabilité(due à la dispersion). L’écart de résultat entre le modèle compact et un modèle SPICE complet est de 6%. / This thesis focuses on different aspects of ”Low Energy Design”. First, reversible logic, as it is the first attempt for low energy computing, is briefly dis- cussed. Then, we focus on dynamic energy saving in the combinational part of CMOS circuits. We propose a new method to reduce glitches based on dual threshold voltage technique. Simulation results report more than 16% average glitch reduction. We also show that combining dual-threshold to gate-sizingtechnique is very interesting for glitch filtering as it brings up to 27 % energy savings. In the third part of this dissertation, we have been interested in sub-threshold operation where the minimum energy can be achieved using a reduced supply voltage. Sub-threshold operation has been an efficient solution for energy-constrained applications with low speed requirements. However, it is very sensitive to process variability which can impact the robustness and effective performance of the circuit. We propose a model valid in sub and near threshold regions in order to correctly estimate the circuit performance in a variability aware analysis. We provide an analytical solution for the optimum supply voltage that minimizes the total energy per operation while considering variability effects. Spice simulations matches the analytical result to within 6%.

University research buildings are significant energy consumers in the United States. There is therefore a need to reduce energy use on the nation's campuses, not only cutting their carbon footprints but also saving money. Universities' efforts to reduce energy use include updating older facilities, implementing renewable energy systems, and encouraging energy saving behavior. This study evaluated the differential effects of two forms of feedback on electricity consumption in two groups of research buildings on a college campus to determine whether providing feedback to energy users has an impact on energy conservation behavior. A control group of buildings received no feedback regarding their electricity use. In the first study group of buildings, occupants received information about their electricity consumption with some electricity saving tips, distributed via email. The same procedure was followed with building occupants in the second study group, who received additional information showing their electricity consumption performance in comparison to other buildings within the study group. The baseline reading was conducted a week before the experiment began in August, 2012. Over the course of the five week study, the daily adjusted average reductions in electricity usage compared to the control group were less than 1 percent for both study groups, with study group 1 achieving an average reduction of 0.2 percent and study group 2 an average reduction of 0.8 percent. Although the reduction observed for study group 2 was 4 times greater than that for study group 1, the saving was not continuous over the study period. Accordingly, the result was deemed to be not statistically significant and the effectiveness of comparative energy use feedback in university research buildings was not supported. However, even small savings in the energy used in university research buildings can be very important in terms of the total amount of energy saved because research buildings use significantly more energy than other buildings on campus such as academic buildings and residence blocks. This study concludes with a consideration of potentially fruitful directions for future research into developing new ways to reduce the energy consumption on university campuses. / Master of Science

Akademiska Hus AB är ett statligt ägt fastighetsbolag med uppdrag att äga och förvalta fastigheter för utbildning, forskning och studentbostäder. Ett av deras energimål är att halvera mängden inköpt energi till år 2025 med startår 2000. Syftet med detta examensarbete är att undersöka förbättringsmöjligheter och åtgärder kopplade till VVS-system för att nå energimålet. Arbetet har utförts på förvaltningsområdet Campus Solna som har ett specialavtal med Stockholm Exergi för fjärrvärme och fjärrkyla. Specialavtalet är utformat med fördelaktiga tariffer vid hög nyttjandegrad, ett exempel är kompensation vid användning av fjärrkyla under vinterperioden men det föreligger tilläggsavgifter vid underutnyttjad leverans. Detta sätter begränsningar i vilka typer av besparingsåtgärder som kan utföras med positivt ekonomiskt resultat samt minskad andel inköpt energi. De besparingsåtgärder som har valts för beräkningar är två typer av värmepumpslösningar och ett byte till effektivare värmeåtervinningsbatterier. Beräkningarna har utförts med hänsyn till gällande avtal och därefter jämförts mot ett annat befintligt standardavtal inom Akademiska Hus för att undersöka om förvaltningsområdet Campus Solna skulle gynnas av en annan avtalsform. Nyttjandetiden för fjärrvärme och fjärrkyla är ett förhållande mellan energi och effekt visar resultatet att de åtgärder där den procentuella andelen mellan energi- och effektbesparing är ungefär lika stor finns största ekonomiska lönsamheten. Resultatet efter utförda beräkningar visar att de två typerna av värmepumpslösningar ger stora besparingar i inköpt energi men i förhållande till effektbesparingarna generar detta tilläggsavgifter och en ekonomisk förlust. Vid jämförelse mot standardavtalet utan tilläggsavgifter sparas en stor andel inköpt energi och den potentiella ekonomiska besparingen ökar. Dock, visade det sig vid en totalkostnadsanalys att den årliga kostnaden för värmepumpslösningen med standardavtalet blir lika stor som kostnaden med det befintliga avtalet utan någon åtgärd och detta på grund av att tarifferna för inköpt fjärrvärme och fjärrkyla är högre. Värmeåtervinningsbatterierna har ett bättre förhållande mellan energi- och effektbesparing vilket resulterar i en ekonomisk vinst även vid gällande avtal. Eftersom återvinning av värme minskar andelen förbrukad energi är det även positivt ur en miljö- och hållbarhetssynpunkt. Slutsatsen är att om det befintliga avtalet fortsätter att nyttjas måste åtgärder som skapar ett bra förhållande mellan energi- och effektbesparing hittas. Alternativet är att försöka förhandla fram ett nytt avtal när gällande specialavtal löper ut för att göra åtgärder som värmepumpar lönsamma. Utöver ovannämnda undersökning har arbetsmetoderna för energibesparingar på Akademiska Hus undersökts genom kvalitativa intervjuer där syftet var att belysa hur nuvarande samarbete ser ut mellan de olika yrkesrollerna samt om det finns en tydlig strategi för hur energimålet ska nås. En slutsats efter utförda intervjuer är att det upplevs att det finns för lite tid att genomföra ett energiarbete. Bakomliggande orsak till detta anses vara att det skulle behövas en bättre arbetsmetodik, tydligare struktur för arbetsfördelning samt mer resurser i form av en dedikerad arbetsgrupp som jobbar operativt med energifrågan. / Akademiska Hus AB is a government owned real estate company, their primary mission is to own and administrate facilities for education, research and student housing. One of their energy goals is to reduce the amount of acquired energy by half between the year 2000 and 2025. The purpose of this thesis is to find solutions and ways to make improvements regarding HVAC-systems to achieve this energy goal. The work has been carried out at the property area Campus Solna, which have an agreement with special amendments and conditions with Stockholm Exergi concerning district heating and cooling. The agreement is designed with beneficial tariffs at high utilization, one example is that during the winter season Akademiska Hus gets compensated for using the district cooling but it also exists surcharges at underutilization of delivered heating and cooling. This puts limitations in which types of measures that can be performed to reduce the amount of acquired energy and at the same time have a positive economical result. The selected solutions are two different types of heat pumps and a change to more efficient heat recovery exchangers for ventilation. The calculations have been executed with regard to the current special agreement and then compared to another existing agreement within the corporation to examine if Campus Solna would benefit from another agreement. The utilization time for the district heating and cooling consist of a relation between energy and power, results show that saving measures where the ratio between them are about the same size is the most profitable economically. The results after the performed calculations show that the two types of heating pumps generate large savings in acquired energy but in relation to the reduced power usage causes surcharges and an economical loss. When compared to the other agreement without the additional charges the potential economical outcome improves while reducing the acquired energy. However, when performing a total cost analysis, the calculations with the other agreement indicate that the total annual cost for acquired energy with the heating pump solutions will amount to the same as using the existing agreement without performing any energy saving measures. This is due to the difference in tariffs between the agreements. The heat recovery exchangers have a better relation between energy and power savings, which results in an economical profit regardless of the agreements. This measure also decreases the consumed energy, which has a positive impact on the environment and sustainability. In conclusion, if the current agreement is to be used in the future energy saving measures have to meet the requirement of the energy and power ratio. However, finding enough of such measures that helps Campus Solna to achieve their energy goal can be problematic. The alternative is to renegotiate the agreement to make solutions like heat pumps profitable. Through qualitative interviews with a selection of personnel, work methods connected to energy saving has been discussed to see if there are possibilities for improvements regarding collaboration between the different departments to achieve the energy goal. One conclusion after the interviews is that the personnel are experiencing that there is not enough time to focus on energy savings and projects in their daily work. Hence, there is a need for better working methods, a clearer structure for how the work is to be distributed and more resources in the form of a dedicated working group that works operationally with the energy issue.

The problem of energy saving during overhaul of a linear part of gas trunkline is regarded in this paper. This issue has been analyzed from different perspectives. Thermodynamic analysis of gas evacuation from a string that is off operation for the overhaul to a parallel or adjacent string with the use of mobile compressor systems was made. Economical attractiveness of mobile compressor systems applications was proved. Various methods of gas trunklines linear parts overhaul have been considered. For each of the methods problems of minimization of necessary for the overhaul amount of energy consuming machines have been solved. The results can be used in the development of overhaul projects of the gas trunklines linear parts.