Dissertations / Theses: 'Energy- and cost-efficient measures'

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Simmons, Brian Spencer. "Lowest cost building technology selection for energy efficient design." Thesis, Georgia Institute of Technology, 2012. http://hdl.handle.net/1853/45941.

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The thesis project explores the use of an optimization methodology for selecting the lowest monetary cost combinations of technologies to meet a set operational energy efficiency targets for buildings. The optimization approach, which is operated on a normative energy model, is compared with existing prescriptive methodologies for selecting technology combinations and a metric is developed for ranking their effectiveness; the E/C Ratio. The energy savings/ cost ratio is also the objective function that the optimization algorithm is set to maximize. The optimization routine is coded in to a custom MATLAB script and is used in two case studies to optimize a proto-typical Korean apartment and office building. The optimization methodology finds technology combinations that are much more cost effective than the prescriptive methodology at meeting an energy savings target and can generically be applied to other buildings given a palette of technology alternatives and the corresponding cost data.

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Jonsson, Leo. "Energy Audit of the multi- residential buildings at “Sicklaön 124:2” : Calculation of energy- and cost saving measures." Thesis, Högskolan i Gävle, Avdelningen för bygg- energi- och miljöteknik, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-17378.

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Boyko, Vladimir, and Jürgen Weber. "Combinations of energy saving measures in pneumatics." Technische Universität Dresden, 2020. https://tud.qucosa.de/id/qucosa%3A71216.

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Within a production machine, various electromechanical and pneumatic structures can be used for drive tasks. As these drive technologies can often replace each other, the energy efficiency, performance and TCO of pneumatic drives must be permanently enhanced to remain competitive. There is a large number of known measures for the reducing their energy consumption, e.g. minimizing of filling volumes, energy saving circuits etc. However, these measures are mainly considered separately and the possible overall energy saving effect resulting from their combination is rarely taken into account. The main goal of this paper is therefore to explore the possible combinations of pneumatic energy saving measures and their cumulative saving effect. Due to the fact that some measures are mutually exclusive (e.g. a general pressure reduction in properly sized drive), each combination should be considered separately. To evaluate their efficiency plausibly, a comprehensive assessment is required that contains both the total cost of ownership analysis (TCO) and a mechanical properties assessment. The presented comprehensive approach of the task analysis can serve as example of how an optimal drive configuration for the specific task can be found, thus creating a basis for solving constructive challenges in designing of pneumatic automation systems.

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Margelou, Dimitra. "Indoor thermal comfort and associated adaptive measures towards an energy efficient new campus in Borlänge, Sweden." Thesis, Högskolan Dalarna, Energiteknik, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:du-34556.

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Thermal comfort of the occupants is of highest importance specifically in Scandinavian countries. Especially for an educational building, both students and working staff spend most of their time indoors, therefore it is critical to guarantee a healthy and productive indoor climate environment around a whole year. Taking into account that Högskolan Dalarna plans to move into a newly renovated building in the center of Borlänge in 2022, this thesis focus on this essential topic and tries to dig out some valuable adaptive suggestions for the coming schematic design phase. In the next design phase, it aims to satisfy design requirements of Miljöbyggnad 3.0 certification at sliver level, as well as operation requirements of BREEAM InUse at very good level. Consequently, the aim of this thesis project is to have an overall thermal comfort assessment of all representative rooms in the project of the new campus building in Borlänge, Sweden. The thermal comfort assessment consists of both winter situation and summer situation. Both situations are completely under recommended study method from Miljöbyggnad 3.0 with the technical assistant of dynamic building simulation software tool IDA ICE 4.8. Several aspects have been investigated in terms of indoor thermal comfort. The first impacting element is future climate scenarios, so as to check how the future climate will affect the thermal comfort performance. Afterwards, both external and internal shading devices were individually applied to examine and quantify the benefits in terms of indoor thermal comfort. Lastly, the advanced control shading strategies were studied to further improve the thermal comfort performance based on the appropriate conventional shading method. The results showed that future climate scenario has limited impact on the thermal comfort performance when rooms are under temperature controlled via room heating and cooling units. Regarding the shading methods, the internal shading was proved to give a better overall performance. If there is the chance to implement automation shading device, the author recommends the “zone air temperature with operative temperature setpoint 21°C, in which proved to be significantly improved the thermal comfort levels that previously discovered in the vulnerable zones. Therefore, it is expected significantly to reduce the energy dependency during cooling season.

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Kasolas, Kosmas. "Energy savings in multi-family building after using an innovative retrofitting package." Thesis, Högskolan Dalarna, Energiteknik, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:du-34508.

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The building sector is one of the sectors that consume the most energy in Sweden. In order to deal with this problem Swedish government aims to reduce the energy consumption in the building sector 50% by 2050. Another ambitious goal set by the Swedish government is zero greenhouse gas emissions by 2040. Most of the buildings in Sweden were built during 1950-1990 before the first energy regulations were voted in Europe. A high percentage of these buildings date to 1950 and the majority of them are multi family buildings. Apartments built during this period are now requiring major renovation and retrofitting measures in order to comply with the energy and indoor environment regulations. Despite the urgent need for retrofitting expressed above, the retrofitting ratio in Sweden was 0.88% in 2013, so the number of buildings that haven’t gone through any energy retrofitting is still high making it clear that the biggest opportunity for energy savings lies within the existing building stock and that the retrofitting ratio has to enhance in order to achieve the governments energy and emission goals for 2050. In this study a new patented innovative energy retrofitting method is studied within IDAICE simulation program in order to find the heat load and the energy savings after applying this method. The simulated building is a three story multi family building with building characteristics from 1950 and the simulation takes place in two different climate zones (Stockholm and Umeå). Three different insulation thicknesses were tested creating three different variant cases in order to investigate the difference in energy savings an increase of the insulation thickness will bring. This retrofitting method except installation of extra facade insulation includes roof insulation, replacement of the air handling unit with heat recovery ventilation whose pipe system runs through the insulation behind the radiators of each zone and replacement of the old windows with triple glazed low U-value windows. The results show a high reduction in heat supplied after the retrofit, 66.4% room unit heat reduction in Stockholm and 59.6% in Umeå and even higher energy reduction 68.3% in Stockholm and 68.9% in Umeå. The CO2 emission reduction was 58.4% in Stockholm and 60.9% in Umeå. The difference in room unit heat, energy consumption and CO2 emissions among the Variant cases varies between 1-2%. The explanation for such a small difference lies in the fact that the only difference among these cases is the insulation thickness of the facade. The thermal comfort was also investigated and has shown an increase in hours of dissatisfaction after the retrofitting and as the insulation increased due to overheating. However it must be stated here that the reason behind the increase in dissatisfaction is that no window shading or window opening schedules were taken into account in the simulation maximizing the solar heat gains of the building. The study concludes that the studied retrofitting method is very efficient and the studied building achieves higher energy reduction than the goal that the Swedish government has set for 2050. The results of this study bring this retrofitting method ahead of the 2050 energy reduction goals set by the Swedish government with significant reductions in CO2 emissions and heat load.

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Lundström, Lukas. "Heat demand profiles of buildings' energy conservation measures and their impact on renewable and resource efficient district heating systems." Licentiate thesis, Mälardalens högskola, Framtidens energi, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-31495.

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Increased energy performance of the building stock of European Union is seen as an important measure towards mitigating climate change, increasing resource utilisation efficiency and energy supply security. Whether to improve the supply-side, the demand-side or both is an open issue. This conflict is even more apparent in countries such as Sweden with a high penetration of district heating (DH). Many Swedish DH systems have high share of secondary energy resources such as forest industry residuals, waste material incineration and waste heat; and resource efficient cogeneration of electricity in combined heat and power (CHP) plants. When implementing an energy conservation measure (ECM) in a DH connected building stock, it will affect the operation of the whole DH system. If there are CHP plants and the cogeneration of electricity decreases due to an ECM, and this electricity is valued higher than the fuel savings, the consequences of the ECM would be negative. These complex relationships are investigated by conducting a case study on the Eskilstuna DH system, a renewable energy supply system with relatively high share of cogenerated electricity. Heat demand profiles of ECMs are determined by building energy simulation, using recently deep energy retrofitted multifamily buildings of the “Million Programme”-era in Eskilstuna as model basis. How implementing ECMs impact on the DH system’s heat and electricity production under different electricity revenue scenarios has been computed and evaluated in terms of resource efficiency and CO2 emissions. The results show that different ECMs in the buildings impact differently on the DH system. Measures such as improved insulation level of the building’s envelope, that decrease the heat demand’s dependence to outdoor temperature, increase the amount of cogenerated electricity. While measures such as thermal solar panels, which save heat during summer, affects the absolute amount of cogenerated electricity negatively. Revenues from cogenerated electricity influence the amount of cost-effectively produced electricity much more than the impact from ECMs. Environmental benefits of the ECMs, measured in CO2 emissions and primary energy consumption, are quite small in DH systems that have high share of forest residual fuels and electricity cogeneration. The consequences can even be negative if ECMs lead to increased need of imported electricity that is produced resource inefficiently or/and by fossil fuels. However, all studied ECMs increase the relative amount of cogenerated electricity, the ratio between amount of cogenerated electricity and the heat load. This implied that all ECMs increase the overall efficiency of the Eskilstuna DH system.

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Wennerberg, Fåhraeus Maja. "How to succeed with energy efficient refurbishment measures : A study of the CONCERTO initiative, BEEM-UP project and EPC model." Thesis, Uppsala universitet, Institutionen för teknikvetenskaper, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-267908.

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Buildings consume 40 % of Europe’s total energy consumption and causes 33 % of the CO2 emissions. (Pol and Lippert, 2010) Existing old buildings, especially those constructed with limited energy standards before 1960, are in need of refurbishment and energy efficiency. (Economidou, 2011) The thesis is a part of the EU project GrowSmarter, where smart solutions for sustainable cities are to be implemented in the lighthouse cities Stockholm, Cologne and Barcelona. (European Commission, 2014) The purpose of this thesis is to look into the experiences, success factors and barriers from the CONCERTO initiative, BEEM-UP project and EPC model, focusing on energy efficient refurbishment. The intent is that e.g. authorities, municipalities, companies and building owners, who are planning on performing energy efficient refurbishment measures, can access identified success factors and barriers in previous projects of different scale and methods. The conclusions of this study are that the communication and cooperation between stakeholders in a project, knowledge transfer and training of installers are important factors for successful projects. Information and involvement of tenants facilitates work execution, improves results after refurbishment and increases energy knowledge and awareness. The data quantity and quality is another influencing factor on building performance and the difference between calculated and measured energy savings. Stakeholder approach, energy performance regulations, ownership structure and financial status/possibilities for the building owner can affect project results.
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Gomez, Adrian. "Energy audit of a bakery in Sweden." Thesis, Högskolan i Gävle, Energisystem, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-24525.

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In order to reach the European aim for a sustainable growth, the “Triple 20 by 2020”, the energy audit in every sector is one of the keys of the success. In order to carry on with the energetical development, sustainability and future energy efficient systems, the energy efficiency in the industry is one of the most important matters. The Swedish industry uses 147 TWh of energy per year, which represents the 39% of the total final energy use and also the biggest energy user of the three sectors. The food processing industry only uses a 3% of the total Swedish industrial energy use, however this is 4410 GWh per year, what still has high possibilities to reduce the use of energy through different energy efficiency measures.The present study consists on an energy audit of a small-medium industrial bakery in Ockelbo, Sweden, by starting with the compilation of a few energy efficiency measures that are usually carried out on the energy audits. Then those measures have been tried to implement in the bakery in order to reduce the energy use and therefore the costs, which are the principal aims of the study, together with the approach to future energy efficiency ideas. However, the lack of electrical measure equipment has been a big limitation for the study. The method, that has been the guideline for the energy audit, is the Energy management procedure, which is a widely used method on different energy audits. The main measures that have been proposed are regarding the auxiliary processes like lighting and the compressed air system, additionaly, changes regarding the power contract and the installed power of they bakery are presented. Also different future possibilities for the heat recovery are analyzed and discussed like using the waste heat for preheating tap water for the dough processes. Additionally this study contains a wide explanation of the Swedish electrical bills that every company has to pay and probably many of them do not understand.If the presented energy efficiency measures are implemented the electrical energy use can be reduced with at least 23109 kWh per year. In terms of money, the cost savings are at least 57781 SEK per year with an investment of 106300 SEK.

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Ruiz, Gomez Alvaro. "Energy Conservation in the Canadian Residential Sector : Revealing Potential Carbon Emission Reductions through Cost Effectiveness Analysis." Thesis, Internationella Handelshögskolan, Högskolan i Jönköping, IHH, Nationalekonomi, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-16239.

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The study uses Cost Effectiveness Analysis (CEA) as a method to analyse the economicand environmental impact of carbon dioxide (CO2e) emission abatement projects in theCanadian residential sector. It includes the more traditional environmental andeconomic criteria, yet it incorporates a behavioural component to the analysis. Adetailed account of the environmental specifications, emission reductions, and economicconsiderations of 11 abatement projects are used as input for the CEA. In addition,behavioural variables, such as disposable income, home ownership, and home repairskills, are taken into account to complement the study.The results indicate that the implementation of several of these carbon abatementprojects, such as insulating hot water pipes, replacing incandescent light bulbs,installing a programmable thermostat, etc. can bring about large emission reductionstogether with a net economic benefit, and in most cases, without altering the levels ofcomfort. This method can serve as a template for the evaluation of other related projectswithin the climate change mitigation context in Canada and in other countries, in anattempt to increase adoption rates of such projects.

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Vågerö, Oskar. "Alternatives to carbon capture and storage (CCS) in the deep decarbonisation of the Norwegian cement industry : A cost-optimisation study of GHG mitigation measures." Thesis, KTH, Energi och klimatstudier, ECS, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-278198.

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Norway’s two cement manufacturing plants are both among the top 10 largest national point sources of Greenhouse Gas (GHG) emissions and together contribute to 2% of the total GHG emissions. One of the important measures being pushed for to mitigate these emissions is Carbon Capture and Storage (CCS), for which the Norwegian Government is to make an investment decision in 2020/2021. Norway may end up with the first full-scale CCS project in the cement sector on a global basis, so the technology is still in its infancy in industrial applications outside of oil extraction. The aim of the study is to collate and summarise multiple data sources on the different measures that could mitigate greenhouse gases and which are feasible in a Norwegian context, in addition to CCS. The measures included are: energy effciency, fuel substitution, new types of clinkers, material effciency, clinker substitution, and substitution for wooden construction materials or biocement. The study utilises the concept of Marginal Abatement Cost (MAC) and Marginal Abatement Cost Curve (MACC) to assess and illustrate the environmental performance of the different measures versus a baseline scenario of 591 kg CO2e emitted per tonne cement manufactured. The two most promising measures are substituting part of the clinkers from the fnal cement product for a combination of calcined clays and ground limestone as well as increased use of fillers in concrete, which partially replace clinker in the final concrete product. These two measures are inexpensive and does not require any technology leap to implement. Barriers exist in the shape of a conservative construction industry where incremental innovation happen slowly. The industry is also utilising highly standardised product which make the entry of new and changed products diffcult and slow. No combination of measures achieve full decarbonisation of the cement industry, without including CCS, which indicates that it may still be necessary for the cement sector to become carbon neutral.
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Stålheim, Victoria, and Karin Roth. "Energieffektivisering av en 1960-talsvilla." Thesis, Tekniska Högskolan, Högskolan i Jönköping, JTH, Byggnadsteknik, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-19193.

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Miljöfrågor är i dagsläget ett ämne som intresserar och engagerar mångamänniskor på olika plan och inom olika ämnesområden. Kraven från vår regeringoch från EU blir allt stramare och inom området byggteknik finns idag krav på enbyggnads specifika energianvändning vid nybyggnation. Problemet är att det intefinns något specifikt krav på det befintliga beståndet och dessa byggnader har oftahög energiförbrukning. Möjligheten att det inom en snar framtid kommer kommakrav på det befintliga beståndet, likt det som finns för nybyggnation, är inteorimligt. Det är därför viktigt att redan nu se på vilka åtgärder det finns att vidtaför att sänka energiförbrukningen hos äldre byggnader och som riktlinje strävaefter att nå det krav som ställs på nybyggnation. Det finns många möjligheter och tillvägagångssätt till att energieffektivisera detäldre beståndet av bostäder. För att uppnå kvalitet i arbetet har en avgränsninggjorts till att endast studera 1960-talshus och se vilka åtgärder det finns att vidtasamt dess lönsamhet. För att kunna ge ett svar har tre frågeställningar tagits framsom behandlar energideklarationer för 1960-talshus inom Jönköpings kommun,samt en fallstudie av ett 1960-talshus. Studien av energideklarationerna gav kunskap om de vanligaste energibovarna ochvilka kostnadseffektiva åtgärder som kommunen rekommenderar. De vanligasteenergibovarna konstaterades vara köldbryggor, självdragventilation,varmvattenförluster samt värmeförluster via öppen spis. Kommunensrekommenderade kostnadseffektiva åtgärder visade sig som förväntat hautgångspunkt i de vanligaste energibovarna och är vattenbesparingsprodukter, nyregleringsteknik för inomhustemperaturen, fönsteråtgärder, tilläggsisolering avvind samt installation av kassett i öppen spis. Fallstudien med dessenergiberäkningar av 1960-talshuset visade på samma energibovar som varvanligast enligt energideklarationerna. För att förbättra byggnaden urenergisynpunkt togs olika totalrenoveringsförslag för energieffektivisering avbyggnaden fram, och de olika förslagens lönsamhet beräknades.Renoveringsförslagen består av byte av uppvärmningskälla, tilläggsisolering avfasad, vind och grund, byte av fönster samt vilken effekt solfångare bidrar med.För att få fram lönsamheten ställs energiårskostnaden för de olikatotalrenoveringsförslagen mot det ursprungliga oljeuppvärmda husets årligaenergikostnad. De framtagna totalrenoveringsalternativen ger alla en lägre årligenergikostnad jämfört med det oljeuppvärmda ursprungshuset, och inom 20 år harman tjänat in renoveringen. Enligt beräkningar är det mest lönsammatotalrenoveringsalternativet att efter 15 år ha valt putsad fasad medpelletsuppvärmning, och efter 20 år har det varit mest lönsamt att välja putsadfasad med kombinerad sol- och pelletsuppvärmning. Nackdelen med totalrenoveringsförslagen är att alla inte har möjligheten att utföraallt, men att exempelvis enbart byta värmekälla och tilläggsisolera vinden kan göraen skillnad för plånbok och miljö.
Environmental issues are in the current situation a subject of interest and concernto many people at various levels and in different subject areas. The demands fromour government and the EU is becoming increasingly tight and the study ofconstruction technology available today requires a building's specific energyconsumption in new buildings. The problem is that there is no specificrequirement for existing buildings and these buildings often have high energyconsumption. The possibility that in the near future there will come demands forthe existing population, like the demands which exists for new construction, is notunreasonable. It is therefore important that we now look at what action that ispossible to take to reduce energy consumption in older buildings and as aguideline strive to achieve the requirements for new construction. There are many possibilities and approaches to energy efficiency of the olderpopulation of housing. In order to achieve quality of work has a boundary madeto only study house from the 1960s and see what actions it is possible to take andits profitability. In order to give an answer, three questions were presented dealingwith energy declarations for buildings from the 1960s in the municipality ofJönköping, and a case study of a 1960s building. The study of energy declarations gave knowledge of the most common energyleaks and the cost-effective measures that the municipality is recommended. Themost common energy leaks were found to be thermal bridges, natural ventilation,water loss and heat loss through the fireplace. The cost-effective measures that themunicipality’s recommended proved to be, as expected, based on the mostcommon energy leaks and are water saving products, new adjustment techniquesfor indoor temperature, window measures, supplementary insulation of the atticand an installation of a cassette in the fireplace. The case study with its energycalculations of the house from the 1960s showed the same energy villains whowere most common according to the energy declarations. In order to improve thebuilding from an energy perspective was different complete renovation proposalsfor improving energy efficiency of building raised, and the various proposalsprofitability was calculated. Renovation proposals consist of replacing the heatingsource, additional insulation of facade, wind and ground, the replacement ofwindows as well as solar power contribute to. To obtain profitability is annualenergy cost for the complete renovation proposals compared to the originaloil-heated house's annual energy costs. All the designed renovation options gives alower annual energy costs compared to the original oil-heated house, and within20 years it has earned the renovation. According to estimates, the most profitablecomplete renovation proposal after 15 years is to have chosen plaster façade withpellet heating, and after 20 years it has been most profitable to choose plasterfaçade with combined solar and pellet heating. The disadvantage of the complete renovation proposals is that not everyone hasthe ability to accomplish everything, but for example to only change the source ofheat and can make a difference both for his wallet and the environment.

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Darabikelareh, Hedayat, and Tagreed Maqatif. "Rules of thumb for energy-efficient renovation of apartment buildings : The case of Nils Holgersson, the Swedish statistical home." Thesis, Högskolan Dalarna, Institutionen för information och teknik, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:du-37805.

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In Sweden, there are around 300 000 multi-family buildings with high energy consumption state a high renovation potential in the building sector. This study aims to analyze different renovation measures for a typical theoretical multi-family building to determine their effects on energy consumption, financial profitability, and impacts on obtaining an energy label in the rating system. The reference building was created based on the given energy consumption for the Nils Holgersson building (NH), where the information data accumulated and assessed utilizing dynamic energy simulation software IDA ICE.The selected renovation measures include modifications to the building envelope and ventilation. The reference building was equipped with an exhaust ventilationsystem with no heat recovery. The study showed that heat losses through ventilation contributed to the largest share. The losses through windows and walls are significant; hence selecting ventilated façade and adding insulation were relevant efficiency measures. The study analysis a vacuum insulation panel (VIP) applied for external walls due to its highly efficient thermal properties compared to conventional insulation. The results of life cycle cost analyses (LCCA) for 40 years demonstrated that VIP and ventilated façade have an economic benefit because of the energy cost saving during the operation phase of the building, despite the high initial cost. The cumulative LCC for each measure showed that VIP approaching the conventional insulation within theservice life the ventilated façade is cost-efficient at the end of the 6thyear compared to changing glazing. The selected rating system is Miljöbyggnad (MB). After renovation, the NH building could achieve the bronze level on the energy indicators.The study found that the energy consumption in the base model was 144.7 kWh/m2and the implemented renovation package leads to a reduction of 47 % annual heating demand. As a rule of thumb, the annual energy demand will be 90 kWh/m2, and the cost for the renovation package including installation would be 1150 SEK/m2causing a total energy-saving 2900 SEK/m2at the end of 40 years.

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Robert, Andersson, and Rasmus Becke. "Assessment of energy renovation with new design solution of a single-familyhouse in southern Sweden." Thesis, Linnéuniversitetet, Institutionen för byggd miljö och energiteknik (BET), 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-105319.

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To reach the EU directives and Sweden ́s energy- and climate goals, there is a needto implement new innovative- and technical solutions in each sector. The Swedishgovernment predicts that the buildings sectors energy demand could be reduced byrenovating the existing building stock. The research examines the opportunities to implement indoor design solutionsassociated with an energy renovation measure of an existing single-family house inSweden. The research will cover a broader picture of the concept's feasibility-, addedvalues, and financial cost and benefits. This will be done within the requirements ofthe current building regulations on altering an existing building in Sweden 2021. The research outcome showed that implementing the design solution concept willconstitute a financial benefit on energy renovation measure ́s payback time. Theresult showed that one of the suggested design concepts with the energy renovationmeasures would have a payback time of 8.5 years. Besides, implementing the designsolution concept predicts several beneficial added values, e.g., environment, buildingdesign and society.

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Svensson, Fredrik, and Johan Bengtsson. "Kostnadsbesparing med avseende på energieffektiviserande åtgärder med avgränsning till fönsterbyte och tilläggsisolering." Thesis, Linnéuniversitetet, Sjöfartshögskolan (SJÖ), 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-74430.

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Linnéuniversitetet Sjöfartshögskolan i Kalmar Utbildningsprogram: Drift- och underhållsteknik Arbetets omfattning: Självständigt arbete om 15 HP Titel: Kostnadsbesparing med avseende på energieffektiviserande åtgärder med avgränsning till fönsterbyte och tilläggsisolering. Författare: Fredrik Svensson och Johan Bengtsson Handledare: Henrik Wärnberg Sammanfattning 2017 års medelpris för el hamnade på cirka 30 öre per kWh. Det är åtta procent högre än för 2016 och hela 32 procent högre än 2015, då elpriset var väldigt lågt. 2017 års elpris är det högsta sedan 2013. Fortsättningsvis spår Bixia låga elpriser de kommande åren vilket beror på utbyggnaden av förnybar energi och att kärnkraftverket Olkilouto 3 i Finland tas i drift. Bixia räknar med att den nordiska elmarknaden kommer att ha en förstärkt energibalans fram till 2019. Efter år 2019 kommer energibalansen att försvagas, beroende på stängningen av Ringhals 1 och 2 och ökad export av el ut från Norden, säger Martina Rosenberg på Bixia. En försvagad energibalans innebär en högre prisnivå. Projektet syftar till att kartlägga omfattningen av energiförluster, i ett privat hushåll, till följd av transmission och därefter göra en bedömning om energibesparingsåtgärder, i form av tilläggsisolering och fönsterbyte, skulle vara en ekonomisk lönsam investering. Genom minskad energianvändning ger dessa investeringar ett positivt tillskott i energibalansen och kan även bidra till en bättre inomhusmiljö. Projektet följer en metod där kvalitativa experiment har utförts genom mätningar på klimatskärmen. Denna mätning har gjorts med hjälp av en termografikamera där bilder har detekterat otätheter i klimatskärmen, så kallade köldbryggor. Energiförluster, till följd av transmission, har sedan beräknats med handberäkningsmetoder och utförts för en rad olika storheter, exempelvis värmeledningsmotstånd och värmegenomgångskoefficienter. Utöver detta har den specifika klimatskärmen delats upp i flera sektioner respektive skikt för att strukturerade beräkningar skulle kunna utföras enligt den beräkningsgång detta projekt efterföljt. Undersökningen visar att åtgärderna bidrar till omkring 4 gånger mindre energiförluster gällande energifönster och 2 gånger mindre för väggen jämfört med värdena före åtgärder. Återbetalningstiden är dock betydligt längre för energifönstren då detta är en betydligt mer kostsam investering. För PVC-fönster landar återbetalningstiden på ca 27 år och för aluminiumbeklädda träfönster är återbetalningstiden i detta fall över 40 år mot ca 20 år för tilläggsisoleringen.
Linnaeus University Kalmar Maritime AcademyEducation programs: Operation and MaintenanceScope of work: Independent work of 15 HPTitle: Cost savings with regard to energy efficiency measures with delimitation of window change and additional insulationAuthor: Fredrik Svensson and Johan Bengtsson Supervisor: Henrik Wärnberg Abstract The 2017 average electricity price ended at around 30 Swedish “öre” per kWh. It is eight percent higher than in 2016 and 32 percent higher than in 2015, when the price for the electricity was much lower. The 2017 electricity price is the highest since 2013. Continuingly, Bixia's low electricity prices predict the next few years, which is due to the expansion of renewable energy and that the Olkilouto 3 nuclear power plant are put into use in Finland. Bixia expects the Nordic electricity market to have a strengthened energy balance until 2019. After 2019, energy balance will weaken due to the closure of Ringhals 1 and 2 and increased exports of electricity from the Nordic countries, says Martina Rosenberg from Bixia. A weakened energy balance means a higher price level. The project intention is to mapping the extent of energy losses, in a private household, due to transmission and subsequently assessing energy saving measures, in the form of additional insulation and exchange of windows, would be a profitable investment. Through reduced energy consumption, these investments provide a positive boost to the energy balance and can also contribute to a better indoor environment. The project follows a method where qualitative experiments have been carried out through measurements on the climate screen. This measurement has been done by using a thermographic camera where images have detected thermal unevennesses in the climate screen that is called cold bridges. Energy losses due to transmission have then been calculated by hand calculation methods and performed for a variety of quantities, such as heat conductivity resistors and thermal coefficients. In addition, the specific climate screen has been divided into several sections and layers, so that structured calculations could be performed according to the calculation process followed by this project. The survey shows that the measures contribute to is about 4 times less energy losses on energy windows and 2 times less for the wall than the pre-measure values. However, the repayment time is significantly longer for the energy windows, as this is a significantly more costly investment. For PVC windows, the repayment period is approximately 27 years. For aluminum clad wood windows, the repayment period in this case is over 40 years to about 20 years for the additional insulation.

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15

Panayiotou, Gregoris. "Thermal performance of dwellings in Cyprus and approaches for energy conservation." Thesis, Brunel University, 2014. http://bura.brunel.ac.uk/handle/2438/9204.

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Energy has always been the dominant driving force for the socio-economic development of mankind. Nowadays, the global energy system is highly depended on fossil fuels. A great share of the final energy consumption, over 40%, in the EU-27 is consumed by the existing building stock whereas dwellings account for 66.62% of this. Thus, the need to increase the energy performance of dwellings is an important instrument in the efforts to lessen Europe’s energy dependency. In order to define measures to increase the energy performance of dwellings a deeper understanding of their characteristics should be gained. Unfortunately, in Cyprus there is a gap in knowledge on this aspect. In this thesis the characteristics of the dwellings in Cyprus are defined through a sample of 500 dwellings. The results revealed that more than 80% of dwellings in Cyprus do not have thermal insulation installed on their envelope. From this it is clear that the definition of the optimum thermal insulation material to be applied in dwellings is very important. Thus, the commercially available thermal insulation materials and topologies used in Cyprus were reviewed and defined through a market survey and the typical dwelling was modelled. The effect of the application of thermal insulation to its energy behaviour was simulated using TRNSYS. This resulted in the definition of the optimum thermal insulation materials and topologies to be applied in both new and existing dwellings. Accordingly, the application of advanced commercially available materials such as Phase Change Materials (PCM) to the envelope of the typical dwelling was investigated. The energy savings achieved by the addition of a PCM layer on the envelope of the typical dwelling was found to be 28.6%. The optimum PCM case was also combined with the optimum thermal insulation combination and an energy saving of 68% was predicted. The incorporation of Renewable Energy Sources (RES) to the typical dwelling was also simulated and studied. Specifically, two types of standalone RES systems were initially evaluated; a solely photovoltaic (PV) system and a hybrid PV-Wind system. The results showed that the solely PV system is a much better option due to the very high solar potential of Cyprus in comparison to the poor wind profile of the island. Subsequently, a grid-connected PV system was also evaluated and the results showed that when a RES system is grid-connected the cost of the system is reduced to half of that of the standalone cases. This research has revealed that the optimum topology combinations to be applied in both new and existing dwellings in Cyprus is thermal insulation plaster or thermal insulation bricks (only for new dwellings) on the external walls combined with expanded polystyrene on the roof. These results will provide valuable information that will assist both engineers and architects in the efficient design of dwellings in Cyprus. The investigation of the application of macroencapsulated PCM showed that these materials are not yet an economically viable solution for application in Cyprus The findings also show that a solely PV system is the optimum RES system to be applied in Cyprus especially when it is grid-connected. The findings of this project are useful for individuals, house builders and designers as well as policy makers for the design of energy saving subsidy schemes.

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Hamzaoui, Sami, and Alex Goro. "Planeringsprocessen av ROT-projekt : En studie angående ekologiskt hållbara ROT-projekt i miljonprogrammen." Thesis, Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-55149.

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Between year 1961 and 1975 were about one million homes produced, which today is called the million programme. These homes are now in a great need of renovation as they contain hazardous substances in the materials, unnecessarily high energy use and they are in critical technical condition. Purpose: of the degree project is to identify how we can become increasingly sustainable in ROT-projects within the million programme areas. The degree projects studies among other things how a renovation will be sustainable, materials and waste impact, about the million programme rebuilding needs and rebuilding needs of low-energy houses in the million programme. The method: The degree project is based on a literature study, a questionnaire study and an interview study. The literature study has been carried out to gain an increased knowledge of how a ROT-project works and facts about the million programme. The survey consisted of questions about what the environmental work looks like in various ROT-projects. Entrepreneurs working on ROT-projects, landlords who manage housing in the million programme and tenants who live in the million programmehave participated in the survey. An interview study has been conducted with various ROT-entrepreneurs and landlords to get an overview of how the work of the million programmehas looked environmentally. The result: The million programme leak large amounts of energy and heat. Older have shown that greenhouse gas emissions and energy use have increased, so the need for renovation is becoming more apparent. Sustainable renovation is needed to reduce the negative environmental impact of greenhouse gas emissions and energy gas. In a construction process does material production have a major impact on the environment. When it comes to material selection and waste management is an important aspect for the environment within a ROT-project. In order to be able to work in an environmentally friendly way, it is necessary to plan in detail about various factors when handling the use of materials. The various factors are inventory, waste sorting, ordering materials in the right dimension, choosing materials with regard to the environment and handling the materials well during the construction process. Conclusion: The million programme homes are energyintesive and require among other things trunk replacement, ventilation replacement, replacement of electrical installations, windows, balconies and facades. In order to renovate the million programme homes good knowledge is required about ay hazardous substances in the materials and what measures are required to make the homes more energy efficient.

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17

Zhang, Wenying S. B. Massachusetts Institute of Technology. "Cost and benefit of energy efficient buildings." Thesis, Massachusetts Institute of Technology, 2006. http://hdl.handle.net/1721.1/36819.

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Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2006.
Includes bibliographical references.
A common misconception among developers and policy-makers is that "sustainable buildings" may not be financially justified. However, this report strives to show that building green is cost-effective and does make financial sense today. Though green buildings typically have a higher upfront cost compared to conventional constructions, they do offer benefits that simply built-to-code projects lack. These benefits include cost savings from reduced energy and water use, less waste production, diminished environmental and emissions costs, lower operations and maintenance costs, and enhanced occupant productivity and health. These values range from being fairly predictable (energy and water savings can be recorded over time) to relatively uncertain (productivity/health benefits are somewhat arbitrary and subjective). Based on a 20-year Net Present Value analysis with a 5% real interest rate, a recent study by the California Sustainable Energy Task Force showed the total financial benefits of green design to be $50/ft2 - $75/ft2, depending on the building's level of LEED Certification. This number is over ten times bigger than the average 2% cost premium calculated for the 33 green buildings they analyzed-about $3-5/ft in California.
(cont.) Energy savings alone, from reduced energy demand and decreased peak load, was calculated to be $5.79, which already exceeds the cost premium. Conservative calculations based on a study on Norway building retrofits show that the cost of energy savings ranges from 1-4 cents/kWh. Comparing this number to the cost of various modes of electricity generation, ranging from 3-80 cents/kWh, it is clear that the cost of generating electricity greatly exceeds the cost of saving energy through energy efficient buildings. Thus, green buildings are cost effective and should be more widely adopted.
by Wenying Zhang.
S.B.

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18

Schneider, Eric B. "Studies in historical living standards and health : integrating the household and children into historical measures of living standards and health." Thesis, University of Oxford, 2014. http://ora.ox.ac.uk/objects/uuid:f2e55a37-c605-4aba-8a2e-3d699c6b82b7.

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This dissertation attempts to integrate the household and children more fluidly into measures of well-being in the past. In part one, I develop a Monte Carlo simulation to test some of the assumptions of Allen’s welfare ratio methodology. These included his assumptions that family size was constant over time, that there were no female-headed households and that women and children did not participate in the labour force. After all of the adjustments, it appears that Allen’s welfare ratios underestimate the welfare ratios of a demographically representative group of families, especially if women and children’s labour force participation is included. However, the predicted distributions also highlight the struggles of agricultural labourers, who are given separate consideration. Even the average agricultural labourers’ family with women and children working would have had to rely of self- provisioning, gleaning, poor relief or the extension of the working year to make ends meet at the poorest point in their family life cycle. Part two adjusts Floud et al.’s estimates of calorie availability in the English economy from 1700 to 1909 for the costs of digestion, pregnancy and lactation. Taken together, these three additional costs reduced the amount calories available by around 15 per cent in 1700 but only by 5 per cent in 1909 because of the changing composition of the English diet. Part three presents a new adaptive framework for studying changes in children’s growth patterns over time and a new methodology, longitudinal growth studies, for measuring gender disparities in health in the past. An adaptive framework for understanding growth provides a more parsimonious explanation for the vast catch-up growth achieved by slave children in the antebellum American South. The slave children were only able to achieve this catch-up growth because they were programmed for a tall height trajectory by relatively good conditions in utero. Finally, impoverished girls experienced greater catch-up growth than boys in two schools in late-nineteenth century Boston, USA and early-twentieth century London, suggesting that girls were deprived relative to boys before entering these institutions.

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Unzeitig, Filip. "Kritické srovnání vládních postupů za účelem dosažení vyšší energetické efektivnosti bytové a nebytové výstavby ve vybraných zemích EU." Master's thesis, Vysoké učení technické v Brně. Fakulta podnikatelská, 2011. http://www.nusl.cz/ntk/nusl-222898.

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Práce srovnává, jak vlády vybraných Evropských zemí stimulují občany a podniky k tomu, aby stavěli energeticky úsporně se zaměřením na ekonomickou stránku věci. Práce srovnává poznatky, sjednocuje je a vyvozuje patřičné závěry.

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20

Yu, Yiting. "Energy- and Cost-Efficient 5G Networks in Rural Areas." Thesis, KTH, Skolan för informations- och kommunikationsteknik (ICT), 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-204403.

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Energy- and cost-efficiency is becoming a criteria of ever increasing importance in the design of 5G wireless solutions, especially for suburban and rural areas where the realistic barrier of providing mobile broadband service lies in the economic drawback of low revenue potential. Thus net-work operators are highly sensitive to the energy performance and economic affordability of potential solutions in futuristic 5G wireless network.In this thesis, we investigate the energy performance of 5G wireless networks with two key technical components (massive beamforming and ultra-lean design) in a rural environment for two real-life cases commonly faced by network operators: (1) A hardware upgrade to 5G in existing LTE sites (2) 5G greeneld deployments. The results are compared with a currently deployed LTE network in rural environment. Furthermore, we conduct economic viability evaluations in a study of energy-cost trade-off in rural scenario to derive the condition when the proposed energy-efficient 5G solutions are also cost-efficient. The analysis are performed separately in two cases based on different methods. The simulation results indicate that 5G systems provides much better energy performance compared with LTE systems, achieving maximum 56% and 64% reduction in daily average area power consumption in hardware upgrade case and greenfield deployment case respectively. The significant saving mainly comes from the incorporated effect of beamforming technology and possibility of longer sleep durations. For cost-efficiency, a hardware upgrade to 5G is economically highly motivated in higher energy-pricing regions or in systems with longer sleep durations. In greenfield deployments, the analysis result shows that itis always cost-efficient to deploy 5G solutions other than LTE solutions in rural areas despite of the variation in regional energy prices, network lifetime expectation and the DTX factor in 5G solutions.
Energi- och kostnadseffektivitet blir ett kriterium av ständigt ökande betydelse i utformningen av 5G trådlösa lösningar, särskilt för förorts- och landsbygdsområden där den realistiska hinder att ge mobilt bredband ligger i den ekonomiska nackdelen med låg intäktspotential. Således nätverksoperatörer är mycket känsliga för energi och ekonomiska överkomliga till potentiella lösningar i futuristiska 5G trådlöst nätverk. I denna avhandling undersöker vi energiprestanda av 5G trådlösa nätverk med två viktiga tekniska komponenter (massiv strålformning och ultra-lean design) i en lantlig miljö för två verkliga fall som nätverksoperatörerna vanligen står inför: (1) uppgraderingar av maskinvara till 5G i befintliga LTE platser (2) 5G greenfield distributioner. Resultaten jämförs med en idag sköts LTE-nät i lantlig miljö. Dessutom genomför vi ekonomiska utvärderingar i en studie av energikostnader avvägning på landsbygden scenario att härleda villkoret när de föreslagna energieffektiva 5G lösningar är också kostnadseffektivt. Analysen genomförs separat i två fall på olika metoder. Simuleringsresultaten visar att 5G system ger mycket bättre energiprestanda jämfört med LTE system. 5G uppnår en minskning 56 % och 64 % i genomsnittlig daglig område strömförbrukning i hårdvara uppgradering fall och gröna driftsättning fallet respektive. Den betydande besparing kommer främst från den innefattade effekten av strålformning teknik och möjlighet till längre sömn löptider. För kostnadseffektivitet, är en hårdvara uppgradering till 5G ekonomiskt mycket motiverade i högre regionerna energi prissättning eller i system med längre sömn löptider. Greenfield distributioner visar analysresultatet att det alltid är kostnadseffektivt att distribuera andra än LTE lösningar på landsbygden 5G lösningar trots variationen i regionala energipriser, nätverk livstid förväntan och DTX faktor i 5G lösningar.

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21

Beita-Kiser, Gabriel. "Energy Efficient Homes in Tucson: How to Make Cost-Effective Energy Efficiency Retrofits." The University of Arizona, 2015. http://hdl.handle.net/10150/552896.

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22

Norell, Arlid Malin. "Energieffektivisering av äldre flerbostadshus : En analys av energisparande åtgärder i 50-talsflerbostadshus klimatskal, ställd mot deras kostnad." Thesis, Luleå tekniska universitet, Industriellt och hållbart byggande, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-69252.

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Äldre flerbostadshus står för en stor del av Sveriges totala energianvändning som behöver sänkas föratt minska klimatpåverkan och klara regeringsmålet om effektivare energianvändning. Examensarbetets syfte är därför att bidra till en ökad kunskap om energieffektivisering genom åtgärder i äldre byggnaders klimatskärm, och om hur åtgärder kan värderas genom energisimulering och livscykelkostnadsanalys. Målet är att identifiera vilka åtgärder som är ekonomiskt och arkitektoniskt lämpliga för äldre flerbostadshus med intresse av att bevara deras karaktär. Det är även att bedöma vilken energibesparing och livscykelkostnad de utvalda åtgärderna genererar. Ett flerbostadshus i centrala Luleå valdes ut som referensbyggnad. Byggnaden är genom sin konstruktion och design representativ för tidseran. Intressanta åtgärder samt åtgärdspaket i dess klimatskal valdes ut. Sedan utfördes en bred litteraturgenomgång om bostadsbyggandet i Sverige 1945–1964, byggnadens energianvändning, energieffektivisering av klimatskalet, de utvalda åtgärderna samt metoderna energisimulering och livscykelkostnadsanalys. Referensbyggnaden dokumenterades och en energisimuleringsmodell byggdes i programvaran IDA ICE. Den nuvarande utformningen av byggnaden simulerades och kalibrerades mot senast uppmätt normalårskorrigerad energianvändning. Sedan utfördes simuleringar för de utvalda åtgärderna och åtgärdspaketen vilka bestämts till tilläggsisolering av vindsbjälklag, byte av fönster till lågenergifönster och tätning av otätheter runt dessa, en kombination av båda tidigare åtgärder (åtgärdspaket 1), tilläggsisolering av fasad och fönsterbyte, samt en kombination av alla tre åtgärder (åtgärdspaket 2). Livscykelkostnaderna för nuläget och för implementering av de olika åtgärderna beräknades genom nuvärdeskostnadsmetoden. Även återbetalningstider beräknades genom simple-payback-metoden. Byggnadens nuvarande utformning gav efter kalibrering en simulerad energianvändning på 136,2 kWh/(m2Atemp,år); 2,9 % över det senast uppmätta normalårskorrigerade värdet. Nuvärdeskostnaden för att inte utföra någon åtgärd beräknades till ca 2 727 tkr. Åtgärderna genererade energibesparingar på 3,5–14,6 %, nuvärdeskostnader på 2 685-5 880 tkr och återbetalningstider på 7-105 år. För varje adderad åtgärd i klimatskalet ökade energibesparingen. Tilläggsisolering av vindsbjälklag visade sig vara den enda lönsamma åtgärden, då den har en nuvärdeskostnad som är lägre än att inte utföra någon åtgärd. En känslighetsanalys utfördes för kostnadsberäkningarna där diskonteringsräntan höjdes och sänktes med 2 % och energipriset höjdes med 10 %. Tilläggsisoleringav vindsbjälklag kvarstod dock som den enda lönsamma åtgärden. Åtgärderna hade kunnat generera högre procentuell energibesparing för en annan liknande byggnad. Referensbyggnaden innehåller ett stort renoverat kontor vilket ger en lägre nuvarande energianvändning och lägre procentuell energibesparing för åtgärder än om endast den äldre bostadsdelen studerats. Då Luleå har Sveriges lägsta energipris är åtgärder med hög investeringskostnad ekonomiskt svårmotiverade. Detta beror på att kostnadsbesparingarna genom minskad energianvändning blir små i förhållande till åtgärdernas investeringskostnader. Tilläggsisolering av fasad kan inte rekommenderas då åtgärden både är mycket olönsam och förändrar byggnadens uttryck väsentligt. Slutsatsen är att tilläggsisolering av vindsbjälklag är den lämpligaste åtgärden för äldre flerbostadshus, av de undersökta åtgärderna för energieffektivisering i klimatskalet. Den är arkitektoniskt lämplig med hänsyn till bevarandet av byggnaden då den inte förändrar byggnadens utseende. Den är även ekonomiskt lämplig då den har en livscykelkostnad som är lägre änalternativet att inte utföra någon åtgärd. För fortsatta studier föreslås bl.a. att undersöka hur åtgärder kan göras mer attraktiva för fastighetsägare, att kartlägga fastigheter från tidseran (skick, energianvändning, resultat av åtgärder, möjligheter) samt att utvärdera potentialen av ny teknik.
Old multifamily houses stand for a large part of Sweden’s total energy usage, which must decrease to minimize our environmental impact and to accomplish the government goal of more efficient energy usage. The aim of this master thesis is therefore to contribute to an increased knowledge on energy optimization through building envelope improvements in older buildings, and how energy efficiency measures can be evaluated through building energy simulation and life cycle cost analysis. The goal is to identify which measures that are economically and architecturally appropriate for old multifamily houses with interest in retaining their character. It is also to evaluate which energy saving and life cycle cost the selected measures generate. A multifamily house in central Luleå was selected as reference building. The building is by its construction and design representative for the era. Interesting energy efficiency measures in the building envelope were chosen. Then a wide literature study was carried out on house building in Sweden 1945-1964, building energy usage, energy efficiency through building envelope measures, the selected measures and the methods building energy simulation and life cycle cost analysis. The reference building was documented and an energy simulation model was built in the software IDA ICE. A present version of the building was simulated and calibrated to better match the latest normalised annual value. After that, simulations were performed for the selected measures; additional attic insulation, change to low energy windows and weather stripping these, a combination of both previous measures, additional facade insulation and change of windows, and a combination of all three measures. The life cycle costs of the present situation and for implementation of the different measures were calculated through the net present cost method. Also, payback times were calculated through the simple payback method. The building in its original state showed a post-calibration energy usage of 136,2 kWh/(m2Atemp,year); 2,9 % above the surveyed value. The net present cost for not performing any energy conservation measures was calculated to about 2 727 SEK. The measures generated energy savings of 3,5-14,6 %, net present costs of 2 685 -5 880 SEK and payback times of 7-105 years. For each added measure in the building envelope, the energy saving increased. Additional insulation of the attic turned out to be the only profitable measure, since its net present cost is lower than for not performing any energy conservation measure. A sensitivity analysis was performed for the cost analyses where the discount rate was raised and lowered by 2 % and the energy price raised by 10 %. However, the additional attic insulation remained as the only profitable measure. The energy conservation measures could have generated greater energy savings for a similar building. The reference building contains a large retrofitted office which lowers the present energy usage and the percental energy savings for measures compared to if only the dwelling part had been studied. Since Luleå has Sweden’s lowest energy prices, measures with high investment costs become difficult to give grounds for. This is because the cost savings achieved by their energy savings are low compared to their investment costs. Additional facade insulation cannot be recommended since it both is very unprofitable and highly changes the appearance of the building. The conclusion is that additional attic insulation is the most appropriate energy conservation measure for old multifamily houses, of selected measures in the building envelope. It can be regarded as architecturally appropriate since it does not change the building appearance. It is also economically appropriate since its life cycle cost is lower than for not performing any measure. Suggested future research includes analyzing how energy efficiency measures can be made more attractive for real estate owners, charting real estate from the era (condition, energy usage, results from measures, opportunities) and evaluating the potential of new technology within the field.

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23

Abtahi, Farzad. "Optimal Design of Cost- and Energy-Efficient ScalablePassive Optical Backbone Networks." Thesis, KTH, Skolan för informations- och kommunikationsteknik (ICT), 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-116891.

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Advances in optical coherent transmissions and electrical compensation technologies have stimulated the exploration of novel optical network architectures. Filterless optical backbone networks (F-OBNs) eliminate or minimize the usage of active photonic reconfigurable components, which is also referred to as passive OBN. By introducing passive splitters and combiners to interconnect the fiber links, this type of networks have been proposed as a cost- and energy-efficient alternative to active optical switching networks. However, F-OBN suffers from a constraint on wavelength reuse due to its broadcast nature. Consequently, this architecture always requires more resources, i.e. higher number of wavelengths, than the active optical switching networks. To address this issue, another passive approach for optical core network, i.e., semi-filterless OBN (SF-OBN) has been introduced. By utilizing passive colored components, e.g., Fiber Bragg Grating (FBG), red/blue filters, etc., at some selected nodes, the SF-OBN is able to improve the wavelength usage while keeping the similar level on cost and energy consumption as FOBN. In this thesis project, an optimization model for wavelength assignment and filter placement in SF-OBN has been developed. F-OBN can be considered as a special case without any filter in SF-OBN. Using integer linear programming (ILP) formulation, the model aims to minimize the total number of wavelengths required in the network given the number of filters. Furthermore, wavelength usage, cost and energy consumption in active optical switching, F-OBN and SF-OBN have been compared in order to evaluate the performance of the each network architecture.

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Zhu, Jiannan. "Novel energy-efficient DWDM systems for low-cost optical communication applications." Thesis, University of Cambridge, 2015. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.709467.

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Mendoza, Martin Jose. "Raceway system requirements for low-cost energy-efficient algal biomass cultivation." Thesis, University of Southampton, 2016. https://eprints.soton.ac.uk/400675/.

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The overall aim of the research was to investigate the hydraulic mixing characteristics and energy efficiency of raceway systems for the large-scale cultivation of micro-algae. For this purpose, two pilot-scale raceway reactors (100 m length x 1 m wide channel), each with a paddlewheel for liquid circulation and a sump for gas exchange, were built and tested under different conditions. The optimal depth to run the raceway was 0.20 m. At this depth, a typical velocity for liquid circulation in raceways of 0.20 m s-1 was obtained with a power consumption of 2.10 W m-3, which was reduced to 1.6 W m-3 by using one baffle in the bend. At this velocity, addition of two and three baffles did not influence the power consumption significantly. The study of mixing as indicated by the Bodenstein number showed that mixing took place mainly in the paddlewheel, sump and bends although the overall behaviour of the system was plug flow since most of the liquid was contained in the channels. A study with and without a sump baffle showed that the maximum velocity achieved when it was in place was 37 % lower than without the baffle, while at the same time the power consumption increased by 79 %. In addition, its presence reduced mixing, while the improvement in mass transfer was very low. For all these reasons, a sump baffle with the studied configuration was not recommended unless its hydrodynamic performance can be significantly improved. The selection of a membrane plate diffuser giving a small bubble size and low pressure drop enhanced mass transfer efficiency. Oxygen was desorbed mainly in the sump and paddlewheel due to high turbulence which increased the mass transfer coefficient. Peaks in dissolved oxygen at midday, however, were identified as a major problem causing growth inhibition. Accumulation of oxygen in the culture can be reduced by gas bubbling in the sump, although in cultures with a high concentration of bicarbonates CO2 stripping may occur. CO2 mass transfers above 96 % were achieved in the raceway, highlighting the efficiency of the sump as a device for gas exchange. The use of flue gas was effective to control pH, provide carbon to the culture and reduce dissolved oxygen peaks. A carbon balance showed that outgassing in the raceway was almost negligible and main carbon loss was through the liquid phase in the harvesting process. Use of a hydrostatic pressure wheel for lifting water increased the hydraulic efficiency of the raceway between 15-20 %. The paddlewheel equipped with shoe used around 40-50 % of the energy required by flat configuration. This corresponds to an improvement of 2-5 times existing efficiencies, with higher values occurring at longer simulated channel lengths where the hydrostatic head losses are greater. This efficiency, however, is still well below theoretical values, and there is scope for further optimization the improved paddlewheel design for specific raceways.

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Nesdoly, Mark J. "Affordable cost-in-use and neighborhood renewal through energy efficient housing renovations." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp05/MQ62809.pdf.

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Sianga, Busisiwe Elizabeth. "An approach to sustainable, energy efficient design for low-cost housing in Botswana." Pretoria : [s.n.], 2007. http://upetd.up.ac.za/thesis/available/etd-09222008-144556.

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Vupparige, Vijaykumar Sanjana. "A Cost-Efficient Bluetooth Low Energy Based Indoor Positioning System for IoT Applications." Thesis, Linköpings universitet, Institutionen för datavetenskap, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-162208.

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The indoor positioning system is a series of networking systems used to monitor/locate objects at indoor area as opposed that of GPS which does the same at outdoor. The increase in the popularity of the Internet of Things made the demand for Bluetooth Low Energy technology more and more essential due to their compatibility in the smartphones which makes it to access easier. The BLE’s reliable signal and accuracy in calculating the distance has a cutting edge on others in IPS. In this thesis, the Bluetooth Low Energy indoor positioning system was designed and implemented in the ofﬁce area, and the positionofIoTdevicesweremonitored. OntheIoTdevices,thebeaconswereplaced. And thesebeaconswerecoveringtheofﬁcearea. Thereceiver,smartphoneinourcase,recorded theReceivedSignalStrengthIndicationofthetransmittedsignalsfromthebeaconswithin the range of the signal and stored the collected data in a database. Two experiments have beenconducted. Oneisforbeaconsthatarestationaryandonethatismoving. Toevaluate these experiments, a few tests were performed to predict the position of beacons based on therecordedreceivedsignalstrength’s. Inthecaseofstationarybeacons, itoffersaccuracy range from 1 m to 5 m, and 3 m to 9.5 m in anticipating the position of each beacon in the case of moving beacon. This methodology was a mixture of ﬁngerprinting and an algorithm of multilateration. Finally, the experiments show that the algorithm used provides the most accurate indoor position using BLE beacons that can be monitored through an Android-based application in real-time.

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Tombaz, Sibel. "On the Design of Energy Efficient Wireless Access Networks." Doctoral thesis, KTH, Radio Systems Laboratory (RS Lab), 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-144868.

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Wireless access networks today consume 0.5 percent of the global energy. Rapidly growing demand for new services and ubiqutious connectivity, will further increase the energy consumption. This situation imposes a big challenge for mobile operators not only due to soaring cost of energy, but also increasing concern for global warming and sustainable development. This thesis focuses on the energy efficiency issue at the system level and studies how to incorporate energy-awareness into the design of future wireless access networks. The main contributions have been given in the areas of energy efficiency assessment, architectural and operational solutions, and total cost of investment analysis. The precise evaluation of energy efficiency is the first essential step to determine optimized solutions where metrics and models constitute the two key elements.We show that maximizing energy efficiency is not always equivalent to minimizing energy consumption which is one of the main reasons behind the presented contradictory and disputable conclusions in the literature. Further we indicate that in order to avoid the debatable directions, energy efficient network design problems should be formulated with well defined coverage and capacity requirements. Moreover, we propose novel backhaul power consumption models considering various technology and architectural options relevant for urban and rural environments and show that backhaul will potentially become a bottleneck in future ultra-high capacity wireless access networks. Second, we focus on clean-slate network deployment solutions satisfying different quality of service requirements in a more energy efficient manner. We identify that the ratio between idle- and transmit power dependent power consumption of a base station as well as the network capacity requirement are the two key parameters that affect the energy-optimum design.While results show that macro cellular systems are the most energy efficient solution for moderate average traffic density, Hetnet solutions prevail homogeneous deployment due to their ability to increase the capacity with a relatively lower energy consumption and thus enable significant energy savings in medium and high capacity demand regions. Moreover, we investigate the energy saving potential of short-term energy aware management approach, i.e., cell DTX, taking advantage of low resource utilization in the current networks arising from strict QoS requirements. With the help of developed novel quantitative method, we show that Cell DTX brings striking reduction in energy consumption and further savings are achievable if the networks are designed taking into account the fact that network deployment and operation are closely related. Finally, we develop a general framework for investigating the main cost elements and for evaluating the viability of energy efficient solutions.We first reveal the strong positive impact of spectrum on both energy and infrastructure cost and further indicate that applying sustainable solutions might also bring total cost reduction, but the viability highly depends on unit cost values as well as the indirect cost benefits of energy efficiency. Results obtained in this dissertation might provide guidelines for the network designers to achieve future high-capacity and sustainable wireless access networks.

QC 20140505

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Pietri, Ilia. "Cost-efficient resource management for scientific workflows on the cloud." Thesis, University of Manchester, 2016. https://www.research.manchester.ac.uk/portal/en/theses/costefficient-resource-management-for-scientific-workflows-on-the-cloud(4cfe73ce-1de9-411b-8288-f463d6b52680).html.

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Scientific workflows are used in many scientific fields to abstract complex computations (tasks) and data or flow dependencies between them. High performance computing (HPC) systems have been widely used for the execution of scientific workflows. Cloud computing has gained popularity by offering users on-demand provisioning of resources and providing the ability to choose from a wide range of possible configurations. To do so, resources are made available in the form of virtual machines (VMs), described as a set of resource characteristics, e.g. amount of CPU and memory. The notion of VMs enables the use of different resource combinations which facilitates the deployment of the applications and the management of the resources. A problem that arises is determining the configuration, such as the number and type of resources, that leads to efficient resource provisioning. For example, allocating a large amount of resources may reduce application execution time however at the expense of increased costs. This thesis investigates the challenges that arise on resource provisioning and task scheduling of scientific workflows and explores ways to address them, developing approaches to improve energy efficiency for scientific workflows and meet the user's objectives, e.g. makespan and monetary cost. The motivation stems from the wide range of options that enable to select cost-efficient configurations and improve resource utilisation. The contributions of this thesis are the following. (i) A survey of the issues arising in resource management in cloud computing; The survey focuses on VM management, cost efficiency and the deployment of scientific workflows. (ii) A performance model to estimate the workflow execution time for a different number of resources based on the workflow structure; The model can be used to estimate the respective user and energy costs in order to determine configurations that lead to efficient resource provisioning and achieve a balance between various conflicting goals. (iii) Two energy-aware scheduling algorithms that maximise the number of completed workflows from an ensemble under energy and budget or deadline constraints; The algorithms address the problem of energy-aware resource provisioning and scheduling for scientific workflow ensembles. (iv) An energy-aware algorithm that selects the frequency to be used for each workflow task in order to achieve energy savings without exceeding the workflow deadline; The algorithm takes into account the different requirements and constraints that arise depending on the workflow and system characteristics. (v) Two cost-based frequency selection algorithms that choose the CPU frequency for each provisioned resource in order to achieve cost-efficient resource configurations for the user and complete the workflow within the deadline; Decision making is based on both the workflow characteristics and the pricing model of the provider.

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Persson, Urban. "Realise the Potential! : Cost Effective and Energy Efficient District Heating in European Urban Areas." Licentiate thesis, Högskolan i Halmstad, Energiteknik, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-17281.

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The Member States of EU27 need to accelerate the integration of energy efficient technology solutions to reach the 20% energy efficiency target set for 2020. At current pace, projections indicate that only half of expected primary energy reductions will be reached. To meet the energy demands of growing populations and a vibrant economy, while simultaneously reducing primary energy supplies, the European continent faces a new kind of challenge never previously encountered. The identification and application of feasible, competitive, and comprehensive solutions to this problem are of highest priority if the remaining gap is to be closed in time. How is this multi-dimensional and complex dilemma to be dissolved? In this work, expanded use of district heating technology is conceived as a possible solution to substantially reduce future primary energy demands in Europe. By extended recovery and utilisation of vast volumes of currently disregarded excess heat from energy and industry sector fuel transformation processes, district heating systems and combined generation of heat and power can improve the general efficiency of the European energy balance. To investigate the possible range of this solution, this thesis introduces a set of methodologies, theoretical concepts, and model tools, by which a plausible future excess heat utilisation potential, by means of district heat deliveries to residential and service sectors, is estimated. At current conditions and compared to current levels, this potential correspond to a threefold expansion possibility for directly feasible district heating systems in European urban areas and a fourfold increase of European excess heat utilisation.

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Leboeuf, Francois. "Advanced analysis of measured data for efficient operation of modern buildings." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for energi- og prosessteknikk, 2011. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-13499.

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The aim of this study is to define several methods that enable to estimate the heat exchanged in the different components of an air handling unit (AHU), and propose control strategy optimizations. The AHU studied is a part of a low energy office building located in Norway. The focus is especially made on its rotary heat recovery system, its heating/cooling coil and its heating coil. The data of one month recorded by the building energy management system (BEMS) have been used. The heat exchanged estimation methods presented in this paper are based on heat balances, valve positions and heat exchangers number of transfer unit (NTU). Comparison of the results obtained with the different methods outlined a poor quality of the valves positions signals. This fact has also been confirmed using a statistical method, the principal component analysis (PCA). Because of this issue, the methods proposed have not been validated. Regarding control strategy optimization, the use of a heat exchanged estimation method is required. The estimation method based on NTU has been used as reference, since this method does not use the valves positions signals. The goals of control strategy optimization are to reduce the energy costs and the CO2 emission. The proposed improvements are based on a new distribution between components of input heat, regarding the specific energy cost and CO2 emission of components. The tested optimizations gave better results that the current control strategy, but since the method used as reference has not been validated, these conclusions have to be confirmed after a resolution of the valves positions signals problems.

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Alkenaidari, Abdullah. "Moving toward energy efficient buildings: A growing economic challenge for Saudi Arabia." University of Cincinnati / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1563271864341021.

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Bagheri, H. (Hamidreza). "Mobile clouds: a flexible resource sharing platform towards energy, spectrum and cost efficient 5G networks." Doctoral thesis, Oulun yliopisto, 2017. http://urn.fi/urn:isbn:9789526217413.

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Abstract Recent advances in wireless communications coupled with the widespread of bandwidthhungry and high-power consuming wireless services as well as the rapid penetration of multimedia-enabled smart handheld devices generate a drastic growth in mobile traffic volume. With these trends, the goals of 5G and beyond wireless communications include energy efficiency, low latency, and low service cost from the user’ perspective as well as spectrum efficiency, revenue increasing, and lower capital and operational cost from the network operators’ point of view. This thesis studies the potential of mobile clouds for improving energy, spectral, and cost efficiency towards the primary goals of 5G networks. Mobile clouds define a promising 5G integrated technology which combines the conventional cellular and shortrange networks into a novel and powerful communication architecture. Mobile clouds can be seen as a flexible and efficient platform for cooperative content delivery, cooperation, resource sharing, and social networks. Research work in this thesis is conducted in two main areas, namely fundamental and applied research on mobile clouds. Fundamental research focuses on cloud formation strategies and cloud maintenance mechanisms. In the applied area, the potential of mobile clouds for content distribution is investigated in both licensed and unlicensed bands. For content distribution using unlicensed band, several cooperative strategies are designed and their efficiency is compared to traditional multicast strategy in terms of energy efficiency, content distribution latency, and users’ quality of experience (QoE). In content distribution over licensed band, spectrum sharing and resource allocation algorithms are considered for multi pair and full-duplex device-to-device (D2D) communications, aiming at improving spectral efficiency and network performance as well as quality of service (QoS) provisioning. In addition, a business model is designed to consider how mobile clouds can reduce the cost of users and operators while improving revenue of operators and increasing users’ satisfaction. The results of this thesis show that mobile clouds technology creates a flexible and efficient platform which can efficiently enhance spectral efficiency, significantly improve energy efficiency and network performance while guaranteeing cost efficiency for users and network operators simultaneously
Tiivistelmä Langattomassa viestinnässä on viime aikoina saavutettu useita edistysaskeleita samalla kun suurta kaistanleveyttä edellyttävien ja paljon tehoa kuluttavien langattomien palveluiden käyttö on yleistynyt ja multimediatoiminnoilla varustetut älylaitteet ovat vallanneet nopeasti markkinoita. Tämän seurauksena mobiililiikenne on lisääntynyt huomattavasti. Näiden suuntausten valossa langattoman 5G-viestinnän ja sitä seuraavien sukupolvien langattoman viestinnän kehitystavoitteita ovat muun muassa seuraavat: käyttäjän näkökulmasta energiatehokkuus, mahdollisimman lyhyet viiveajat ja palvelun käytöstä aiheutuvien kustannusten edullisuus sekä verkko-operaattorin näkökulmasta spektritehokkuus, tulojen kasvattaminen ja aiempaa matalammat pääoma- ja käyttökustannukset. Tässä väitöskirjassa tarkastellaan millaisia mahdollisuuksia mobiilipilvet tarjoavat energia-, spektri- ja kustannustehokkuuden parantamiseen ja siten 5G-verkkojen päätavoitteiden saavuttamiseen. Mobiilipilvi on lupaava osa 5G-teknologiaa, jossa perinteiset solukkoverkot ja lyhyen kantaman verkot yhdistyvät aivan uudenlaiseen ja tehokkaaseen tietoliikennearkkitehtuuriin. Mobiilipilvet voidaan nähdä joustavana ja tehokkaana alustana sisällön yhteisjakelulle, yhteistyölle, resurssien jakamiselle ja toiminnalle sosiaalisissa verkoissa. Tätä väitöskirjaa varten on tehty tutkimusta sekä mobiilipilviä koskevan perustutkimuksen että soveltavan tutkimuksen parissa. Perustutkimuksessa keskitytään tarkastelemaan pilvien muodostamisessa käytettäviä strategioita ja pilvien ylläpidossa käytettäviä mekanismeja. Soveltavan tutkimuksen alueella mobiilipilvien tarjoamia sisällön jakelun mahdollisuuksia tarkastellaan sekä luvanvaraisilla että vapaasti käytettävillä kaistoilla. Vapaasti käytettävillä kaistoilla toteutettavaa jakelua varten työssä kehitetään useita yhteistoimintastrategioita, joiden tehokkuutta verrataan perinteiseen monilähetysstrategiaan energiatehokkuuden, sisällön jakelun viiveiden ja käyttäjien kokemuksen laadun (Quality of Experience, QoE) osalta. Luvanvaraisilla kaistoilla toteutettavan sisällön jakelun osalta tarkastellaan moniparisessa ja samanaikaisessa molemminsuuntaisessa laitteiden välisessä viestinnässä (D2D-kommunikaatiossa) käytettäviä spektrin jakamisen ja resurssien allokoimisen algoritmeja, jotta spektritehokkuutta ja verkon suorituskykyä sekä palvelun laatua (Quality of Service, QoS) pystyttäisiin parantamaan. Tämän lisäksi työssä kehitellään liiketoimintamallia, jonka avulla voidaan pohtia, miten mobiilipilvillä voidaan vähentää käyttäjien ja operaattorien kustannuksia ja samalla kasvattaa operaattorien tuloja ja parantaa käyttäjien tyytyväisyyttä. Tämän työn tulokset osoittavat, että mobiilipilviteknologia on joustava ja tehokas alusta, jolla voidaan lisätä olennaisesti spektritehokkuutta, parantaa merkittävästi energiatehokkuutta ja verkon suorituskykyä sekä taata kustannustehokkuus sekä käyttäjien että verkko-operaattorien näkökulmasta

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Yang, You. "Privacy-enhancing and Cost-efficient Energy Management for an End-User Smart Grid in the Presence of an Energy Storage." Thesis, KTH, Teknisk informationsvetenskap, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-214410.

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A smart grid is an energy network which manages the energy generation anddistribution more efficiently following the real-time energy demands of end-usersthrough control and communication technologies. Deploying smart grids canimprove the energy efficiency, enhance the network reliability, and reduce costsof both the energy provider and end-users. However, these benefits come withprivacy challenges. One of such challenges is the smart meter privacy problem.In a smart grid, the smart meter is used to record the real-time energy supplyand to feedback the records to the energy provider. Since the energy is suppliedon the demand, these smart meter records contain the information of energydemand profile of the end-user and therefore it brings the risk of compromisingconsumers’ privacy. Regarding this issue, a rechargeable energy storage canbe used to mitigate this risk by manipulating consumers’ energy consumptionprofile. However, privacy enhancement will lead to increasing the consumers’cost for purchasing energy, which violates the original cost-saving motivation forconsumers. In this work, we investigate the design of a privacy-enhancing andcost-efficient energy management strategy. In detail, dynamic pricing of energyis assumed so that the consumer has the opportunity to utilize the energy storageto reduce the energy cost. Furthermore, the Kullback-Leibler divergence rate isused as privacy measure, and the expected cost-saving rate is also evaluated. Tostudy the trade-off between privacy and cost, the proposed objective functionis a weighted sum of Kullback-Leibler divergence rate and expected cost-savingrate. We first decompose both Kullback-Leibler divergence rate and expectedcost-saving rate in additive forms over a finite horizon. Based on the predefinedbelief states, we express the overall objective function by state-actionpairs and reformulate the energy management design into an Markov decisionprocess (MDP), and the finite horizon optimal solution can be obtained by usingBellman dynamic programming. Finally, in the special case of independent andidentically distributed (i.i.d) demand, we explicitly characterize a stationarypolicy for the infinite horizon average cost by showing this policy can preserve acertain invariance property of the belief state. And we also show this stationarypolicy can achieve an optimal privacy leakage rate.
Ett smart nät är ett energinätverk som hanterar energigenerering och distributionmer effektivt efter slutanvändarnas energikrav i realtid genom kontrolloch kommunikationsteknik. Genom att distribuera smarta nät kan du förbättraenergieffektiviteten, förbättra nätverk säkerheten och minska kostnadernaför både energileverantören och slutanvändarna. Men dessa fördelar kommermed privata utmaningar. En av dessa utmaningar är problemet med smartamätare. I ett smart nät används den smarta mätaren för att registrera energitillförselni realtid och att återkoppla mätningarna till energileverantören.Eftersom energinlevereras efter begäran, innehåller dessa smarta mätarregisterinformationen om slutanvändarens energibehovs profil och därmed riskerardet att äventyra konsumenternas privatliv. När det gäller denna fråga kanen uppladdningsbar energilagring användas för att minska denna risk genomatt förändra konsumenternas energiförbruknings profil. Förbättringen av privatkommerdock att leda till att konsumenternas kostnad för inköp av energiökar, vilket strider mot den ursprungliga kostnads besparande motivationen förkonsumenterna. I detta arbete undersöker vi utformningen av en privatliv höjandeoch kostnads effektiv energihanterings strategi. I detalj antas dynamiskprissättning av energi så att konsumenten har möjlighet att utnyttja energilagringför att minska sin energikostnad. Vidare används Kullback-Leiblerdivergensvärde som privatliv metrisk, och den förväntade kostnads besparingsvärde utvärderas också. För att studera avvägningen mellan privatliv och kostnadär den föreslagna objektiv funktionen en viktad summa av Kullback-Leiblerdivergensvärde och förvÃďntad kostnads besparings värde. Vi bryter först itubåde Kullback-Leibler-divergens värde och den förväntade kostnads besparingeni additativa former över en finit horisont. Baserat på de fördefinierade antagandenauttrycker vi den övergripande objektiva funktionen med state-action-paroch omformulerar energistyrnings designen i en Markov-beslutsprocess (MDP),och den finita optimala lösningen kan erhållas genom att använda dynamiskBellman-programmering. Slutligen, i det speciella fallet med oberoende ochidentiskt distribuerad (i.i.d) efterfrågan karakteriserar vi uttryckligen en stationärpolitik för den oändliga horisontens genomsnittliga kostnad genom attvisa att denna policy kan bevara en viss invariant egenskap hos trosuppfattningen.Vi visar också att man med den här stationära principen kan uppnå ettoptimalt privatliv läckagevärde.

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Hill, Ryan. "Green ozone technology for water and wastewater treatment : an energy-efficient, cost effective and sustainable solution." Thesis, Queen's University Belfast, 2015. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.680079.

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Xu, Hongjie. "Energy-Efficient On-Chip Cache Architectures and Deep Neural Network Accelerators Considering the Cost of Data Movement." Doctoral thesis, Kyoto University, 2021. http://hdl.handle.net/2433/263786.

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付記する学位プログラム名: 京都大学卓越大学院プログラム「先端光・電子デバイス創成学」
京都大学
新制・課程博士
博士(情報学)
甲第23325号
情博第761号
京都大学大学院情報学研究科通信情報システム専攻
(主査)教授小野寺秀俊, 教授大木英司, 教授佐藤高史
学位規則第4条第1項該当
Doctor of Informatics
Kyoto University
DFAM

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Linse, Matilda. "An Investigation of Cost-Efficient Solutions in Order to Meet the Energy Requirements in Multi-Family Buildings." Thesis, KTH, Energiteknik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-189524.

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As the requirement for specific energy usage is tightened it becomes more important to ensure that the most cost-efficient combinations of energy saving measures are presented. This master thesis have been developed based on one main research question and two sub-questions; How can MOBO and IDA ICE be utilized to identify cost-efficient combinations of energy saving measures to meet tightened requirements for specific energy usage?; Which parameters are included in such an utilization?; and How can the number of interesting data points be decreased so that the most appropriate solution is found?. In order to answer the questions MOBO and IDA ICE have been utilized by varying different windows, the amount of insulation in external floors and roofs as well as different air handling units can be varied simultaneously. Thus the most cost-efficient combinations of energy saving measures can be obtained through a systematic approach. Furthermore a cost-efficiency analysis has been made for installation of waste water heat exchanger, solar PVs and a pre-heating system for ventilation air. The cost-efficiency analysis is made from a basis of a tightened requirement of specific energy usage by 30 %.The results have been obtained by utilizing MOBO in combination with IDA ICE. By a large number of simulations through MOBO on four case studies the most cost-efficient combination of energy saving measures is presented. By simulations on different case studies it was shown that the shape of the Pareto fronts are similar. The results show that it is important to set the initial conditions of a building so that it is possible to reach tightened requirements for specific energy usage. In case the initial conditions are poor it can be seen that the requirement cannot be met cost-efficient since the number of energy saving measures are large and the relative investment cost increases rapidly.The conclusion of the main research question is that MOBO could be used in an early stage of the development process so that the initial conditions can be set in such a way that the tightened requirements for specific energy usage can be met cost-efficient. Cost-efficient combinations of energy saving measures can be identified by utilizing MOBO in combination with IDA ICE. Furthermore, energy saving measures that result in a significant energy saving to a relatively small additional investment cost can be found. Lastly, by utilizing MOBO new technical platforms can be developed with a systematic approach.The conclusion of the first sub-question is that the following parameters are included; three different AHUs, three different window resources with different u-values, two different external walls, three different amount of additional insulation in the roof and two different amount of insulation in the external floor. Furthermore, the results obtained by utilizing MOBO and IDA ICE can be combined by installations of WWHex and solar PVs in case it is cost-efficient. An additional analysis should be made for each case.The conclusion of the last sub-question is that the number of interesting data point can be reduced by only use the Pareto front. In addition a tightened requirement of specific energy usage in combination with a budget requirement results in only a few appropriate combinations of energy saving measures.
I takt med att energikraven i byggnader skärps ställs det allt högre krav på att säkerställa att de mest kostnadseffektiva lösningarna presenteras. Denna mastersuppsats har baserats på en huvudfrågeställning och två delfrågeställningar; Hur kan MOBO och IDA ICE användas för att hitta kostnadseffektiva kombinationer av energibesparande åtgärder, för att uppnå skärpta krav på specifik energianvändning?; Vilka parametrar inkluderas i en sådan användning?; och Hur kan antalet intressanta datapunkter reduceras så att den mest lämpliga kombinationen av energibesparande åtgärder presenteras?. För att besvara dessa frågor har MOBO och IDA ICE används där olika fönster, mängd isolering i tak och grundplatta samt olika luftbehandlingsaggregat varierats samtidigt. Detta för att erhålls de mest kostnadseffektiva lösningarna på ett systematiskt sätt. Vidare har en kostnadseffektivitetsanalys gjorts för installation av avloppsvärmeväxlare, solceller samt ett förvärmningssystem för ventilationsluft. Kostnadseffektivitetsanalysen är utförd utifrån tesen att kravet på specifik energianvändning troligtvis kommer att skärpas med 30 %.De resultat som erhållits är framtagna med användning av MOBO i kombination med IDA ICE. Efter ett flertal simuleringar med hjälp av MOBO och IDA ICE har resultat erhållits där de mest kostnadseffektiva kombinationerna av energibesparande åtgärder för olika fallstudier kan presenteras. Efter att MOBO används på olika byggnader har det visats att formen på Pareto-fronterna är av samma karaktär. De resultat som erhållits visar att det är viktigt att säkerställa att de initiala förutsättningarna möjliggör att det går att uppnå skärpta energikrav. Vid mindre bra grundförutsättningar blir det inte kostnadseffektivt att uppnå ett skärpt energikrav eftersom antalet energibesparande åtgärder blir fler och därmed skenar den relativa investeringskostnaden iväg onödigt mycket.Slutssaten av huvudfrågeställningen är att genom att använda MOBO i ett tidigt skede av projekteringen kan de initiala förutsättningarna sättas på ett sådant sätt att det är möjligt att uppfylla skärpta energikrav kostnadseffektivit. Genom användning av MOBO kan kombinationer av energibesparande åtgärder utvärderas på ett systematiskt sätt. Vidare kan åtgärder som har en relativt liten investeringskostnad och som samtidigt har en signifikant energibesparing identifieras. Dessutom kan MOBO användas för att utveckla de tekniska plattformarna.Slutsatsen av den första delfrågan är att följande parametrar inkluderas; tre olika luftbehandlingsaggregat, tre olika fönster med olika U-värden, två olika ytterväggar, tre olika mängder tilläggsisolering i tak samt två olika mängder isolering i grundplattan. Vidare kan resultaten som erhållits med hjälp av MOBO och IDA ICE fördelaktigt analyseras i kombination med ytterligare åtgärder såsom avloppsvärmeväxlare och solceller utifrån en kostnadseffektivitetsanalys. I ännu sällsynta fall kan det vara aktuellt med installation av ett förvärmningssystem för ventilationsluft.Slutsatsen av den andra delfrågan är att antalet intressanta mätpunkter kan reduceras genom att enbart studera Pareto-fronten samt att ett skärpt energikrav i kombination av ett budgetkrav enbart ger ett fåtal passande kombinationer av energibesparande åtgärder.

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Baydogan, Mustafa Gokce. "Energy Efficient Coverage And Connectivity Problem In Wireless Sensor Networks." Master's thesis, METU, 2008. http://etd.lib.metu.edu.tr/upload/12609688/index.pdf.

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In this thesis, we study the energy efficient coverage and connectivity problem in wireless sensor networks (WSNs). We try to locate heterogeneous sensors and route data generated to a base station under two conflicting objectives: minimization of network cost and maximization of network lifetime. We aim at satisfying connectivity and coverage requirements as well as sensor node and link capacity constraints. We propose mathematical formulations and use an exact solution approach to find Pareto optimal solutions for the problem. We also develop a multiobjective genetic algorithm to approximate the efficient frontier, as the exact solution approach requires long computation times. We experiment with our genetic algorithm on randomly generated problems to test how well the heuristic procedure approximates the efficient frontier. Our results show that our genetic algorithm approximates the efficient frontier well in reasonable computation times.

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Stefanoiu, Ana. "Vers l'évaluation de la performance des bâtiments à haute efficacité énergétique." Thesis, Université Grenoble Alpes (ComUE), 2017. http://www.theses.fr/2017GREAA007/document.

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En France, le secteur du bâtiment est le principal consommateur d'énergie. En outre, le secteur de la maison individuelle représente environ 60% des constructions annuelles de logements. La construction des bâtiments à haute efficacité énergétique représente un grand pas vers l'économie d'énergie. Cependant, même si divers efforts sont déployés dans ce domaine, des outils et des méthodes manquent pour évaluer la performance énergétique de ces bâtiments. Cette évaluation doit permettre non seulement de comprendre les facteurs qui contribuent à cette performance mais également d'identifier les causes de la surconsommation, d’inconfort pour les occupants.Cette thèse vise à contribuer à cet objectif en proposant une approche d'évaluation de la performance énergétique d'un bâtiment. Pour cela on compare la performance réelle et la performance attendue en utilisant le monitoring et la simulation thermique dynamique. Cette approche s’appuie sur différents cas d’études dont principalement une maison individuelle, situé en un climat méditerranéen.Dans un premier temps, en phase de conception, nous utilisons des simulations thermiques dynamiques pour étudier l’impact du comportement sur les besoins énergétiques. L'objectif est d'analyser l'influence du scénario d'occupation sur le comportement du bâtiment et d'établir une plage de valeurs pour les besoins en énergie, basée sur des statistiques nationales. Le comportement du bâtiment est étudié en fonction de différents types de scénarii d'occupation, de consignes de température, de l'utilisation d’appareils domestiques et l'éclairage.Dans un second temps, l'accent est mis sur l'évaluation globale de la performance de l'enveloppe. Un test dynamique in situ innovant a été développé pour en évaluer la performance réelle. Ce test est applicable sur une période courte (de l’ordre de la journée) tout en maitrisant les débits d’infiltrations. La comparaison des résultats théoriques en régime stationnaire avec les résultats expérimentaux montre une bonne précision inférieure à 10%.Enfin, le suivi énergétique en continu des maisons performantes est étudié. Tout d’abord, des travaux sont réalisés dans l’optique de réduire le nombre de capteurs nécessaires au suivi, tout en minimisant la perte d’informations. Ensuite, une méthodologie d’instrumentation est développée et appliquée à une maison individuelle. Le suivi de cette maison a pu être étudié sur les six premiers mois de monitoring et a permis d’expliquer le comportement du bâtiment et ses consommations au regard de son usage et de faire le lien avec les prévisions faites en phase de conception
In France, the building sector is the main energy consumer. Moreover single-family houses represent about 60% of annual dwelling construction. The construction of energy efficient buildings represents a big step into energy saving. However, even though various efforts are made within this field, there is still a lack of methodologies about how to evaluate the energy performance of these buildings. The performance evaluation of an energy efficient building should allow understanding factors that contribute to its energy performance and as well as identifying the causes of overconsumption, poor indoor conditions.This thesis seeks to contribute to this field, by proposing an approach towards evaluating the energy performance of a house. This is done by comparing the real performance and the expected performance, using monitoring and building performance simulation, from design to operational phases. The energy performance evaluation approach is carried out on different cases of studies, mainly on a single-family house, situated in a Mediterranean climate.First, in the design phase, we use building performance simulation models to study the dispersions in energy use related to occupant’s behavior. The goal is to analyze the influence of the occupancy scenario on the behavior of the building and to establish a range of values for energy demand, based on national statistics. This step study the building’s behavior based on different types of occupancy scenarios, appliances and lighting use and temperature set point.Then, the focus is on the global evaluation of the envelope’s performance. Within the present thesis an innovative in-situ dynamic test is developed to assess the real envelope’s performance. This test is adapted to occupied houses (as it only takes 2 days) while controlling the infiltration air flow. The comparison between theoretical results of steady state calculation and experimental results show a good precision of less than 10%.Finally, continuous monitoring of energy efficient houses is studied. First, a work is done to reduce the number of sensors required for monitoring, while minimizing the loss of information. Then, an instrumentation methodology is developed and applied to a single-family house. The follow-up of this house could be studied during the first six months of monitoring and allowed to explain the behavior of the building and its consumption with regard to its use and to make the link with the previsions made during the design phase

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Bournique, Guillaume. "Design of an Energy-Efficient and Cost-Effective Cross Laminated Timber (CLT) House in Waikuku Beach, New Zealand." Thesis, KTH, Energiteknik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-193913.

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The Canterbury earthquakes in 2010 and 2011 caused significant damage to the Christchurch building stock. However, it is an opportunity to build more comfortable and energy efficient buildings. Previous research suggests a tendency to both under heat and spot heat, meaning that New Zealand dwellings are partly heated and winter indoor temperatures do not always meet the recommendations of the World Health Organization. Those issues are likely to be explained by design deficiency, poor thermal envelope, and limitations of heating systems. In that context, the thesis investigates the feasibility of building an energy efficient and cost-competitive house in Christchurch. Although capital costs for an energy efficient house are inevitably higher, they are balanced with lower operating costs and improved thermal comfort. The work is supported by a residential building project using Cross Laminated Timber (CLT) panels. This atypical project is compared with a typical New Zealand house (reference building), regarding both energy efficiency and costs. The current design of the CLT building is discussed according to passive design strategies, and a range of improvements for the building design is proposed. This final design proposal is determined by prioritizing investments in design options having the greatest effect on the building overall energy consumption. Building design features include windows efficiencies, insulation levels, optimized thermal mass, lighting fixture, as well as HVAC and domestic hot water systems options. The improved case for the CLT building is simulated having a total energy consumption of 4,860kWh/year, which corresponds to a remarkable 60% energy savings over the baseline. The construction cost per floor area is slightly higher for the CLT building, about 2,900$/m² against 2,500$/m² for the timber framed house. But a life cycle cost analysis shows that decreased operating costs makes the CLT house cost-competitive over its lifetime. The thesis suggests that the life cycle cost of the CLT house is 14% less than that of the reference building, while the improved CLT design reaches about 22% costs savings.
Canterbury jordskalv under 2010 och 2011 orsakade betydande skador på Christchurch byggnadsbeståndet. Det är dock en möjlighet att bygga mer bekväma och energieffektiva byggnader. Tidigare forskning tyder på en tendens att både under värme och plats värme, vilket innebär att Nya Zeeland bostäder är delvis uppvärmda och vinter inomhustemperaturer inte alltid uppfyller rekommendationerna från Världshälsoorganisationen. Dessa frågor kommer sannolikt förklaras av konstruktion brist, dålig värme kuvert, och begränsningar av värmesystem. I detta sammanhang undersöker avhandlingen möjligheterna att bygga en energieffektiv och kostnadseffektiv hus i Christchurch. Även kapitalkostnaderna för ett energieffektivt hus är oundvikligen högre, de är balanserade med lägre driftskostnader och förbättrad termisk komfort. Arbetet stöds av ett bostadshus projekt med Cross Laminated Timber (CLT) paneler. Denna atypiska projekt jämförs med en typisk Nya Zeeland hus (referensbyggnad), både vad gäller energieffektivitet och kostnader. Den nuvarande utformningen av CLT byggnaden diskuteras enligt passiva designstrategier, och en rad förbättringar för byggande föreslås. Denna slutliga designförslag bestäms genom att prioritera investeringar i designalternativ som har störst effekt på byggnaden den totala energiförbrukningen. Byggnadsdesign funktioner inkluderar fönster effektivitet, isolationsnivåer, optimerad termisk massa, armatur, samt VVS och tappvarmvattensystem alternativ. Den förbättrade fallet för CLT byggnaden simuleras med en total energiförbrukning 4,860kWh/år, vilket motsvarar en anmärkningsvärd 60% energibesparing över baslinjen. Byggkostnaden per golvyta är något högre för CLT byggnaden, ca 2900$/m² mot 2500$/m² för timmer inramade hus. Men en livscykelkostnadsanalys visar att minskade driftskostnader gör CLT hus kostnadseffektiv under sin livstid. Avhandlingen visar att livscykelkostnaden för CLT huset är 14% lägre än för referensbyggnaden, medan den förbättrade CLT designen når ca 22% kostnadsbesparingar.

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Kukard, Warren Christopher. "Research on reducing costs of underground ventilation networks in South African mines / Warren C. Kukard." Thesis, North-West University, 2006. http://hdl.handle.net/10394/1639.

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Dillon, Krystal Renee. "A simulation-optimization method for economic efficient design of net zero energy buildings." Thesis, Georgia Institute of Technology, 2014. http://hdl.handle.net/1853/51909.

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Buildings have a significant impact on energy usage and the environment. Much of the research in architectural sustainability has centered on economically advanced countries because they consume the most energy and have the most resources. However, sustainable architecture is important in developing countries, where the energy consumption of the building sector is increasing significantly. Currently, developing countries struggle with vaccine storage because vaccines are typically warehoused in old buildings that are poorly designed and wasteful of energy. This thesis created and studied a decision support tool that can be used to aid in the design of economically feasible Net Zero Energy vaccine warehouses for the developing world. The decision support tool used a simulation-optimization approach to combine an optimization technique with two simulation softwares in order to determine the cost-optimal design solution. To test its effectiveness, a new national vaccine storage facility located in Tunis, Tunisia was used. Nine building parameters were investigated to see which have the most significant effect on the annual energy usage and initial construction cost of the building. First, tests were conducted for two construction techniques, five different climates in the developing world, and three photovoltaic system prices to gain insight on the design space of the optimal solution. The results showed the difference between an economically efficient and economically inefficient Net Zero Energy building and the results were used to provide generalized climatic recommendations for all the building parameters studied. The final test showed the benefits of combining two optimization techniques, a design of experiments and a genetic algorithm, to form a two-step process to aid in the building design in the early stages and final stages of the design process. The proposed decision support tool can efficiently and effectively aid in the design of an economically feasible Net Zero Energy vaccine warehouse for the developing world.

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Lugg, Andrew. "Energy and cost efficient fuzzy environmental services control strategies for achieving high standards of indoor environmental quality and human comfort." Thesis, Cranfield University, 1999. http://hdl.handle.net/1826/4198.

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Building designers aim to create buildings with high quality internal environments which are energy and cost efficient in their use. Failure to attain these objectives simultaneously can lead to reduced building occupant productivities. An important aspect of the building services system which can have a major effect on the provision of occupant comfort within a building is the adopted control strategy. The research project investigated the use of fuzzy control strategies as a means of achieving good standards of comfort provision for occupants while maintaining or improving energy and cost efficiencies for the operation of the building HVAC services. This represented a multi-variant controls objective which was capable of being fulfilled by a fuzzy controller. A one zone building computer model was developed using Matlab and Simulink software as a platform for the development of fuzzy control strategies. The model incorporated building services Heating Ventilating and Air-Conditioning (HVAC) system models. A Proportional + Integral + Derivative (PID) control strategy was used as a benchmark control methodology against which to compare the developed fuzzy control strategies. Three types of fuzzy controller were developed during the course of the research project. These were a Proportional Derivative Fuzzy Controller (PDFC), a Fuzzy Ventilation Controller, and the Fuzzy High Level Controller. The PDFC used the inputs of error and rate of change of error from a specified zone environmental condition set point in much the same way as a PID controller would to control the HVAC plant. Simulation results indicated that the PDFC control strategy was capable of achieving performance levels equal to the conventional PID control strategy. The Fuzzy Ventilation Controller was used to control the rate of fresh outside air entering the building zone through the mechanical ventilation system in order to make use of the "free" cooling and dehumidification available by purging the indoor air when possible. Simulation results showed improvements in the indoor environmental quality provided, and the energy efficiency and cost efficiency of running the HVAC plant. Finally, the Fuzzy High Level Controller used a fuzzy supervisor to control the actions of the fuzzy ventilation controllers. Simulation results showed that the fuzzy supervisor was able to improve the comfort conditions provided and the energy and cost efficiencies of the operation of the HVAC plant when compared to the use of the fuzzy ventilation control strategies alone.

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Färegård, Simon, Marko Miletic, and Schultz Erik von. "Prospects of Renewable Energy for the New City of El Alamein, Egypt : An Energy System Model using OSeMOSYS to obtain the most cost-efficient electricity production mix." Thesis, KTH, Hållbar utveckling, miljövetenskap och teknik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-254405.

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With the motivation to mitigate the effects caused by one of humankind’s biggest challenges, climate change, the purpose of this minor field study was to examine the prospects of renewable energy technologies as part of a larger ambition to offer clean and affordable energy for all, in line with United Nations Sustainable Development Goals. The study was conducted for El Alamein in Egypt, a city under construction that will house four million residents. By combining a field study and an interview with literature search, the information needed for an energy system model was gathered. The modelling system OSeMOSYS was thereafter used to calculate the most cost-efficient electricity mix for the model period of 2020 to 2040, based on different scenarios and technologies. The total discounted cost and amount of emissions were thereafter compared between the scenarios, and the most cost-efficient scenario at reducing emissions was identified. Of the scenarios that were compared to the reference case, the one where 50 % of the electricity was produced from renewables in 2040 proved to be the most cost-efficient option. In addition, this scenario was also the most cost efficient at reducing emissions by a large margin. Regarding the renewable technologies, solar photovoltaics, which represented a majority of the renewable electricity production, was evidently the most cost-efficient technology as well as the one with the highest potential for future implementation, followed by onshore wind power. Moreover, concentrating solar power and waste to energy were proven to have a lower potential. The conclusions drawn were that the city of El Alamein could get a substantial part of its electricity from renewables and that solar PV was the best technology for that purpose. The final conclusion was that there might exist great potential for renewable energy in Egypt.
Med ambitionen att försöka lindra konsekvenserna av vad som idag är en av människans största utmaningar, klimatförändringen, är syftet med denna minor field study att utvärdera förutsättningarna för förnyelsebara energitekniker i Egypten. Detta ligger i linje med en större ambition att erbjuda ren och prisvärd energi i enlighet med de globala hållbarhetsmålen. Fältstudien utfördes i Egypten och omfattade en ny stad under konstruktion, El Alamein, som förväntas hushålla fyra miljoner invånare. En fältstudie och tillhörande intervju kombinerades med en litteraturundersökning för att erhålla nödvändig information som sedan användes i modelleringen av energisystemet. Modelleringsverktyget OSeMOSYS användes för att erhålla den mest kostnadseffektiva energimixen för åren 2020 till 2040, baserat på ett flertal olika scenarier och tekniker. Den totala diskonterade kostnaden samt mängden utsläpp jämfördes mellan de olika scenarierna, och det mest kostnadseffektiva scenariot för att minska utsläpp identifierades. Av de scenarier som jämfördes med referensfallet, så var scenariot där förnyelsebara energitekniker stod för 50 % av elproduktionen år 2040 den mest kostnadseffektiva energimixen för att tillfredsställa behovet samt för att minska mängden utsläpp. Av de förnyelsebara energiteknikerna så visade sig solceller, som stod för en majoritet av den förnyelsebara produktionen, vara den mest kostnadseffektiva tekniken då den i samtliga förnyelsebara scenarier prioriterades av modellen. Därmed visade sig den vara den tekniken med högst potential för framtida implementationer, följt av landbaserad vindkraft. Koncentrerad solkraft i form av soltorn visade sig inte vara kostnadseffektiv då den inte bidrog till produktionen i något scenario. Avfallsförbränningen, som bidrog minimalt till energimixen, saknade tillgång till den mängd bränsle som hade krävts för att den skulle kunnat stå för en större andel av produktionen. Därmed konstaterades det att båda dessa teknologier hade en låg potential för framtida implementationer. De slutsatser som drogs var att staden El Alamein kunde få en betydande del av sin elektricitet från förnyelsebara energikällor samt att solceller var mest lämpad för det syftet då den var mest kostnadseffektiv. Utöver dessa så drogs slutsatsen att det kan finnas stor potential för förnyelsebar energi i Egypten.

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Sutrisno, Harry. "Techno-Economic Study on The Alternative Power and Cooling Systems Design for Cost & Energy-Efficient Edge Cloud Data Center(s)." Thesis, KTH, Skolan för industriell teknik och management (ITM), 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-302990.

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The 5G technology has enabled performance-sensitive applications with low latency and high bandwidth requirements, which has put more low latency requirements on computing services. To answer this need, a small-scale data center called edge cloud is predicted to grow fast in the future. Due to its nature of being close to the end-users, the growth of edge clouds in the populated area may cause a problem with the existing power system. Besides this power system challenge, the edge cloud also requires a higher resource cost than the hyper-scale data center because of the economies of scale. In this thesis, four viable alternative power and cooling technologies are introduced to address those challenges. These four technologies are solar PV, Vertical Axis Wind Turbine (VAWT), Rear Door Heat Exchanger (RDHx), and immersion cooling. Detailed data of edge cloud are required to understand the contribution of these four technologies. However, due to the infancy state of edge cloud, those data are unavailable, and assumptions regarding data are made. Besides that, a cost model for an edge cloud is also required to show how significant the contribution of those alternative technologies is if compared to the total cost of ownership. In this thesis, the cost model for the edge cloud is extended for the alternative power and cooling system scenarios. Along with the assumed data of an edge cloud, sensitivity analysis is performed to determine whether the alternative power and cooling technologies can bring down the cost of edge cloud resources or not. Through the cost modeling, it was found out that VAWT and immersion cooling is not feasible for the particular assumed data center. On the other hand, solar PV can save 4.55% of data center electricity consumption (equal to 0.21% reduction of the total expense when calculated using the current electricity price). Furthermore, RDHx performed better with 22.73% of data center electricity expenses (equivalent to 8.35% of saving from total cost when calculated using the current electricity price).
5G-tekniken har möjliggjort prestandakänsliga applikationer med låg latens och höga bandbreddskrav, vilket har ställt högre krav på låg latens för datatjänster. För att möta detta behov förutspås ett småskaligt datacenter - edge cloud – växa i framtiden. På grund av dess användarnära natur kan tillväxten av edge clouds i tätområden orsaka problem med det befintliga kraftsystemet. Förutom denna kraftsystemutmaning kräver edge cloud också en högre resurskostnad än storskaliga datacenter på grund av skalfördelarna. I denna avhandling introduceras fyra alternativa energi- och kyltekniker för att hantera dessa utmaningar. Dessa fyra tekniker är solpanel, vertikalaxel vindturbin (VAWT), bakdörrvärmeväxlare (RDHx), och nedsänkningskylning. Detaljerad information om edge cloud erfordras för att förstå bidraget från dessa fyra tekniker. På grund av edge clouds tidiga stadium är all nödvändig data dock inte tillgänglig, vaför antaganden om görs. Förutom det krävs också en kostnadsmodell för edge cloud för att visa hur betydande bidraget från den alternativa tekniken är om den jämförs med den totala ägandekostnaden. I denna avhandling utökas kostnadsmodellen för edge cloud för de alternativa energi- och kylsystemscenarierna. Med antagen data för ett edge cloud genomförs en känslighetsanalys för att avgöra om alternativa energi- och kyltekniker kan sänka kostnaden för edge cloud-resurser eller inte. Kostnadsmodelleringen visar att VAWT och nedsänkningskylning inte är möjlig för det specifika antagna datacentret. Å andra sidan kan solpanel spara 4,55% av datacentrets elförbrukning (motsvarande 0,21% minskning av den totala kostnaden när den beräknas med det aktuella elpriset). Dessutom presterade RDHx bättre med 22,73% av datacenters elutgifter (motsvarande 8,35% av besparingen från totalkostnaden när den beräknas med det aktuella elpriset).

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Chen, Chao, and Yogesh Vishwas Bhamare. "Life Cycle Cost Analysis and Optimization of Wastewater Pumping System." Thesis, KTH, Hållbar utveckling, miljövetenskap och teknik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-255866.

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Different attempts have been made to facilitate successful operation of Wastewater Pumping (WWP) system. The WWP units which are already existed in different parts of the world have been studied to identify its success, failure and different parameters associated with its suboptimal performance. The performance of WWP depends on three parameters namely pump, hydraulics, control system and pump station. These parameters are interdependent and must be carefully matched to achieve efficient WWP system. Nowadays the scenario has changed where organizations has started looking increasingly at the total cost of ownership, another way of saying Life Cycle Cost Analysis (LCCA) and recognizing the need to get most out of their equipment purchase. The master thesis includes theory part which describes the different parameters associated with WWP unit especially focusing on Xylems WWP system. This thesis is an attempt to help companies to know how LCCA could be productive management tool in order to minimize maintenance cost and maximize energy efficiency The study reported in this thesis work has been conducted to shed light over the use of Life Cycle Cost Analysis in WWP system. The current study tries to suggest and assess an adopted approach to ensure successful and efficient operation of WWP system with lowering energy demand and decrease in maintenance cost. Initial cost, Maintenance cost and Energy costs are important issues in the operation of WWP system since they are responsible for total cost over time. Therefore, description of each cost, formulas necessary for LCC calculations, data and survey structure, material and energy flow has been described. This work also aims to provide an extensive literature review, different survey and data collection techniques, analysis of collected data, statistical modelling, customer interaction by questionnaires and an interview with experts were used. LCC calculations were used to support the design and selection of most cost-efficient WWP system. Therefore, the given thesis work is an attempt to achieve better functional performance, improve existing design principles associated with WWP System, contribution to asses economic viability, support decision making to enhance operational quality to achieve efficient and successful WWP system.

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Bach, Matthias [Verfasser], Volker [Akademischer Betreuer] Lindenstruth, Owe [Akademischer Betreuer] Phlipsen, and Tilo [Akademischer Betreuer] Wettig. "Energy- and cost-efficient Lattice-QCD computations using graphics processing units / Matthias Bach. Gutachter: Volker Lindenstruth ; Owe Phlipsen ; Tilo Wettig. Betreuer: Volker Lindenstruth." Frankfurt am Main : Univ.-Bibliothek Frankfurt am Main, 2015. http://d-nb.info/1067918248/34.

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Alfonso, Laguna Carlos de. "Efficient and elastic management of computing infrastructures." Doctoral thesis, Universitat Politècnica de València, 2016. http://hdl.handle.net/10251/57187.

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[EN] Modern data centers integrate a lot of computer and electronic devices. However, some reports state that the mean usage of a typical data center is around 50% of its peak capacity, and the mean usage of each server is between 10% and 50%. A lot of energy is destined to power on computer hardware that most of the time remains idle. Therefore, it would be possible to save energy simply by powering off those parts from the data center that are not actually used, and powering them on again as they are needed. Most data centers have computing clusters that are used for intensive computing, recently evolving towards an on-premises Cloud service model. Despite the use of low consuming components, higher energy savings can be achieved by dynamically adapting the system to the actual workload. The main approach in this case is the usage of energy saving criteria for scheduling the jobs or the virtual machines into the working nodes. The aim is to power off idle servers automatically. But it is necessary to schedule the power management of the servers in order to minimize the impact on the end users and their applications. The objective of this thesis is the elastic and efficient management of cluster infrastructures, with the aim of reducing the costs associated to idle components. This objective is addressed by automating the power management of the working nodes in a computing cluster, and also proactive stimulating the load distribution to achieve idle resources that could be powered off by means of memory overcommitment and live migration of virtual machines. Moreover, this automation is of interest for virtual clusters, as they also suffer from the same problems. While in physical clusters idle working nodes waste energy, in the case of virtual clusters that are built from virtual machines, the idle working nodes can waste money in commercial Clouds or computational resources in an on-premises Cloud.
[ES] En los Centros de Procesos de Datos (CPD) existe una gran concentración de dispositivos informáticos y de equipamiento electrónico. Sin embargo, algunos estudios han mostrado que la utilización media de los CPD está en torno al 50%, y que la utilización media de los servidores se encuentra entre el 10% y el 50%. Estos datos evidencian que existe una gran cantidad de energía destinada a alimentar equipamiento ocioso, y que podríamos conseguir un ahorro energético simplemente apagando los componentes que no se estén utilizando. En muchos CPD suele haber clusters de computadores que se utilizan para computación de altas prestaciones y para la creación de Clouds privados. Si bien se ha tratado de ahorrar energía utilizando componentes de bajo consumo, también es posible conseguirlo adaptando los sistemas a la carga de trabajo en cada momento. En los últimos años han surgido trabajos que investigan la aplicación de criterios energéticos a la hora de seleccionar en qué servidor, de entre los que forman un cluster, se debe ejecutar un trabajo o alojar una máquina virtual. En muchos casos se trata de conseguir equipos ociosos que puedan ser apagados, pero habitualmente se asume que dicho apagado se hace de forma automática, y que los equipos se encienden de nuevo cuando son necesarios. Sin embargo, es necesario hacer una planificación de encendido y apagado de máquinas para minimizar el impacto en el usuario final. En esta tesis nos planteamos la gestión elástica y eficiente de infrastructuras de cálculo tipo cluster, con el objetivo de reducir los costes asociados a los componentes ociosos. Para abordar este problema nos planteamos la automatización del encendido y apagado de máquinas en los clusters, así como la aplicación de técnicas de migración en vivo y de sobreaprovisionamiento de memoria para estimular la obtención de equipos ociosos que puedan ser apagados. Además, esta automatización es de interés para los clusters virtuales, puesto que también sufren el problema de los componentes ociosos, sólo que en este caso están compuestos por, en lugar de equipos físicos que gastan energía, por máquinas virtuales que gastan dinero en un proveedor Cloud comercial o recursos en un Cloud privado.
[CAT] En els Centres de Processament de Dades (CPD) hi ha una gran concentració de dispositius informàtics i d'equipament electrònic. No obstant això, alguns estudis han mostrat que la utilització mitjana dels CPD està entorn del 50%, i que la utilització mitjana dels servidors es troba entre el 10% i el 50%. Estes dades evidencien que hi ha una gran quantitat d'energia destinada a alimentar equipament ociós, i que podríem aconseguir un estalvi energètic simplement apagant els components que no s'estiguen utilitzant. En molts CPD sol haver-hi clusters de computadors que s'utilitzen per a computació d'altes prestacions i per a la creació de Clouds privats. Si bé s'ha tractat d'estalviar energia utilitzant components de baix consum, també és possible aconseguir-ho adaptant els sistemes a la càrrega de treball en cada moment. En els últims anys han sorgit treballs que investiguen l'aplicació de criteris energètics a l'hora de seleccionar en quin servidor, d'entre els que formen un cluster, s'ha d'executar un treball o allotjar una màquina virtual. En molts casos es tracta d'aconseguir equips ociosos que puguen ser apagats, però habitualment s'assumix que l'apagat es fa de forma automàtica, i que els equips s'encenen novament quan són necessaris. No obstant això, és necessari fer una planificació d'encesa i apagat de màquines per a minimitzar l'impacte en l'usuari final. En esta tesi ens plantegem la gestió elàstica i eficient d'infrastructuras de càlcul tipus cluster, amb l'objectiu de reduir els costos associats als components ociosos. Per a abordar este problema ens plantegem l'automatització de l'encesa i apagat de màquines en els clusters, així com l'aplicació de tècniques de migració en viu i de sobreaprovisionament de memòria per a estimular l'obtenció d'equips ociosos que puguen ser apagats. A més, esta automatització és d'interés per als clusters virtuals, ja que també patixen el problema dels components ociosos, encara que en este cas estan compostos per, en compte d'equips físics que gasten energia, per màquines virtuals que gasten diners en un proveïdor Cloud comercial o recursos en un Cloud privat.
Alfonso Laguna, CD. (2015). Efficient and elastic management of computing infrastructures [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/57187
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Antonopoulos, Chrissi Argyro. "Diffusion of Energy Efficient Technology in Commercial Buildings: An Analysis of the Commercial Building Partnerships Program." PDXScholar, 2013. https://pdxscholar.library.pdx.edu/open_access_etds/1532.

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This study presents findings from survey and interview data investigating replication of green building measures by Commercial Building Partnership (CBP) partners that worked directly with the Pacific Northwest National Laboratory (PNNL). PNNL partnered directly with 12 organizations on new and retrofit construction projects, which represented approximately 28 percent of the entire U.S. Department of Energy (DOE) CBP program. Through a feedback survey mechanism, along with personal interviews, quantitative and qualitative data were gathered relating to replication efforts by each organization. These data were analyzed to provide insight into two primary research areas: 1) CBP partners' replication efforts of green building approaches used in the CBP project to the rest of the organization's building portfolio, and, 2) the market potential for technology diffusion into the total U.S. commercial building stock, as a direct result of the CBP program. The first area of this research focused specifically on replication efforts underway or planned by each CBP program participant. The second area of this research develops a diffusion of innovations model to analyze potential broad market impacts of the CBP program on the commercial building industry in the United States. Findings from this study provided insight into motivations and objectives CBP partners had for program participation. Factors that impact replication include motivation, organizational structure and objectives firms have for implementation of energy efficient technologies. Comparing these factors between different CBP partners revealed patterns in motivation for constructing energy efficient buildings, along with better insight into market trends for green building practices. The optimized approach to the CBP program allows partners to develop green building parameters that fit the specific uses of their building, resulting in greater motivation for replication. In addition, the diffusion model developed for this analysis indicates that this method of market prediction may be used to adequately capture cumulative construction metrics for a whole-building analysis as opposed to individual energy efficiency measures used in green building.

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