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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

GNSS-mätning vid olika tidpunkter : En studie om osäkerhet / GNSS-measurements at different times : A study of uncertainty

Törnvall, Johan January 2017 (has links)
Syftet med arbetet är att undersöka om olika tidpunkter under dagen påverkar osäkerheten vid GNSS-baserade mätningar. För att undersöka detta så har mätningar gjorts på två kända punkter vid flera olika tillfällen. Mätningarna som jämförts är gjorda på förmiddag, eftermiddag och kväll. Punkterna som använts ligger i Östersund och i Hallen. Utrustning som använts är en handenhet av märket Nomad och en TopCon Hiper II GNSS-mottagare med stativ och trefot. Mätningarna har gjorts med NRTK i koordinatsystemet SWEREF99 14 15. Datat analyserades i SBG GEO och jämfördes sedan i Microsoft Excel. Resultatet blev en genomsnittlig skillnad radiellt på 3 mm i plan. Vid tre av fyra tillfällen så blev osäkerheten mindre på förmiddagen än på eftermiddag/kväll. Den största skillnaden på mätningarna var 8 mm. / The purpose of this study is to investigate whether different times during a day affect GNSSbased measurements. To investigate this, measurements were made on two known points at several occasions. The measurements compared are made in the morning, afternoon and evening. The points used are located in Östersund and in Hallen. The equipment that was used were a Nomad handheld computer and a TopCon Hiper II GNSS receiver with tripod and footer. The measurements were performed with NRTK in the coordinate system SWEREF99 14 15. The data was analyzed in SBG GEO and then compared in Microsoft Excel. The result was an average radial difference of 3 mm in plane. At three out of four times, the accuracy was better in the morning than in the afternoon/evening. The maximum difference between measurements was 8 mm.
12

PanelPlus : Resurs- och miljöanalys / PanelPlus : Resource- and environmental analysis

Bäckström, Elias, Forsberg, Alexander January 2021 (has links)
No description available.
13

Energy efficient and economic renovation of residential buildings with low-temperature heating and air heat recovery

Gustafsson, Marcus January 2015 (has links)
With the building sector accounting for around 40% of the total energy consumption in the EU, energy efficiency in buildings is and continues to be an important issue. Great progress has been made in reducing the energy consumption in new buildings, but the large stock of existing buildings with poor energy performance is probably an even more crucial area of focus. This thesis deals with energy efficiency measures that can be suitable for renovation of existing houses, particularly low-temperature heating systems and ventilation systems with heat recovery. The energy performance, environmental impact and costs are evaluated for a range of system combinations, for small and large houses with various heating demands and for different climates in Europe. The results were derived through simulation with energy calculation tools. Low-temperature heating and air heat recovery were both found to be promising with regard to increasing energy efficiency in European houses. These solutions proved particularly effective in Northern Europe as low-temperature heating and air heat recovery have a greater impact in cold climates and on houses with high heating demands. The performance of heat pumps, both with outdoor air and exhaust air, was seen to improve with low-temperature heating. The choice between an exhaust air heat pump and a ventilation system with heat recovery is likely to depend on case specific conditions, but both choices are more cost-effective and have a lower environmental impact than systems without heat recovery. The advantage of the heat pump is that it can be used all year round, given that it produces DHW. Economic and environmental aspects of energy efficiency measures do not always harmonize. On the one hand, lower costs can sometimes mean larger environmental impact; on the other hand there can be divergence between different environmental aspects. This makes it difficult to define financial subsidies to promote energy efficiency measures. / Byggnader står för omkring 40 % av den totala energianvändningen i EU. Energieffektivisering av byggnader är och fortsätter därför att vara en viktig fråga. Även om stora framsteg har gjorts när det gäller att minska energianvändningen i nya byggnader så är det stora beståndet av befintliga byggnader med dålig energiprestanda förmodligen ett ännu viktigare område att fokusera på. Denna avhandling behandlar energieffektiviseringsåtgärder som kan lämpa sig för renovering av befintliga hus, i synnerhet lågtemperaturvärmesystem och ventilationssystem med värmeåtervinning. Energiprestanda, miljöpåverkan och kostnader utvärderas för en rad systemkombinationer, för små och stora hus med olika värmebehov och för olika klimat i Europa. Resultaten togs fram genom simuleringar med energiberäkningsprogram. Lågtemperatursystem och värmeåtervinning framstod båda som lovande lösningar för energieffektivisering av europeiska hus, särskilt i norra Europa, eftersom dessa åtgärder har större effekt i kalla klimat och på hus med stort värmebehov. Prestandan för värmepumpar, såväl av utelufts- som frånluftstyp, förbättrades med lågtemperaturvärmesystem. Valet mellan frånluftsvärmepump och värmeåtervinning till ventilationsluft kan antas bero på specifika förhållanden för varje fall, men de är båda mer kostnadseffektiva och har lägre miljöpåverkan än system utan värmeåtervinning. Värmepumpen har fördelen att den kan återvinna värme året runt, förutsatt att den producerar varmvatten. Ekonomiska och miljömässiga aspekter av energieffektiviseringsåtgärder stämmer inte alltid överens. Dels lägre kostnad ibland betyda större miljöpåverkan, dels kan det finnas divergens mellan olika miljöaspekter. Detta gör det svårt att fastställa subventioner för att främja energieffektiviseringsåtgärder. / <p>QC 20150904</p>
14

From a complex to a simpler building product Life-Cycle Assessment (LCA) : Focus on simplification of LCA conduct for electronic and electrical equipment

Roy, Axel January 2013 (has links)
No description available.
15

Miljöanalys av en luftrenare : En studie om bedömning av miljöpåverkan och undersökning av förbättringsmöjligheter

Blomberg, Daniel, Sjölén, Ida January 2021 (has links)
Global consumption has increased which has led to a higher burden on the climate. The environmental awareness among consumers is at an all-time high which puts pressure on companies and organizations to minimize their environmental impact. The purpose of this report has been to explore what impact air purifiers have on the environment by doing a life cycle assessment (LCA) of Blueair’s air purifier Blue 3210. The results of the LCA were then used to identify improvement proposals based on ecodesign methodology to reduce the product’s environmental impact.The results of the LCA were used to answer the question “Which part of the product’s life cycle has the greatest environmental impact forthe product Blue 3210?”. The software and database used for the analysis were GaBi and Ecoinvent. The functional unit was defined as the amount of purified air in cubic meters over 3 years.Climate change and particulate matter formation were the chosen characterization factors and different scenarios were created to explore the product’s environmental impact in different contexts. In scenario 1 the air purifier was run at its lowest speed of 2 watts, 24 hours a day, constantly for 3 years. This scenario was used as a reference scenario, as the later scenarios were compared with it. After the results of the LCA were calculated, it could be observed that the main factor of the product’s impact was the energy consumption in its use phase. The LCA showed that the total CO2-emissions in scenario 1 was 43.31 kg CO2-eq. where the use phase accounted for 66%. The total particulate matter formation in the same scenario was 0.12 kg PM10-eq.Finally, improvement proposals were created to answer the question “How can the product Blue 3210 be improved to reduce its environmental impact?”. The proposals were analyzed by using the ecodesign tool The Ten Golden Rules. The three main proposals were: applying an automatic shut-off function, moving the production from China tothe USA and developing washable filters.
16

Use of climate-based daylight models for lighting simulation: A state of the art review of the literature published between 2010 and 2020

JIANG, KAIYUN January 2021 (has links)
Climate-based daylight modelling (CBDM) development, aiming for appropriate sky modelling, has attracted quite some attention during the last years. Ten years ago, it was a challenge to simulate luminous environment dynamics. Over the years, the accuracy of climate models has improved and the need for high precision daylight simulations has been met along with the development of daylight calculation methods. This paper reviews the latest technologies released between 2010 and 2020 for lighting simulation relevant to building science research. After reviewing the development of climate models, advances in daylight calculation methods are discussed. The results of the study show that the accuracy of simulation results has improved significantly based on high precision daylight simulations, but also pose problems of simulation time and simulation feasibility.
17

Hållbara energilösningar för Ulleråker : En studie om integrering av hållbara energilösningar för värmeenergibehovet av stadsdelens planerade nybyggnation / Sustainable energy solutions for Ulleråker : A study on the integration of sustainable energy solutions for the heat energy requirement of the district's planned new construction

Hajek, Isabelle, Bergström, Lina January 2017 (has links)
Uppsala kommun planerar för en ny stadsdel i Ulleråker som ligger söder om Uppsalas stadskärna. Den nya stadsdelen ska utformas med hållbarhet i fokus och ska främja god bebyggelse, sköna naturupplevelser och miljövänliga transportmedel, samtidigt som de måste värna om den underliggande Uppsalaåsen som är kommunens huvudsakliga dricksvattentäkt. Detta arbete ser över det värmebehov som de nya bostäderna kommer kräva, och hur denna skulle kunna tillgodoses med lokala samt förnybara energilösningar. De energilösningar som undersökts är tak monterade vindturbiner, solfångare, borrhålslager och akviferlager. De utvärderas separat baserat på potentiell effekt, dess miljöpåverkan och lämplighet specifikt för området Ulleråker. Rapporten är baserad på litteraturstudie och enklare beräkningar som utförts med hjälp av befintliga data och kartor från myndigheter, institutioner och Uppsala kommun. Antalet takmonterade vindturbiner som krävs för att täcka hela värmebehovet är starkt beroende av turbinernas effekt och med maximal effekt skulle upp till 7190 vindturbiner räcka. Den totala arean för solfångare som skulle motsvara detta ligger på cirka 5000 m2. Ett borrhålslager skulle uppskattningsvis kräva mellan 479 till 4793 borrhål, mycket beroende på vilken värmeledningsförmåga berget har och hur långt ned det är möjligt att borra. Grundvattentäkten skulle som akviferlager kunna generera en effekt på cirka 1000 kW, vilket motsvarar något mer än en tredjedel av det totala behovet. Slutligen undersöktes möjligheten av ett kombinerat system med de lämpliga energilösningarna och ett förslag för hur denna skulle kunna dimensioneras. Vid utvärdering av de olika lösningarnas miljöpåverkan och lämplighet så finner vi att geoenergi kan innebära en risk för den underliggande grundvattentäkten. Framförallt kan akviferlager anses som tämligen olämpligt då anläggningen bygger på en anslutning direkt till dricksvattentäkten. / Uppsala are planning a new district in Ulleråker located south of the city center. The new district will be designed with sustainability in focus and should promote good housing, beautiful outdoor experiences and environmentally friendly transport while protecting the underlying Uppsalaåsen, which is the municipality's main drinking water source. This report looks at the heat demand that the new housing requires and how it could be met with local and renewable energy solutions. The energy solutions investigated are roof-mounted wind turbines, solar collectors, borehole and aquifer thermal energy storage. They are evaluated separately based on potential output, its environmental impact and suitability specifically for Ulleråker. The report is based on literature studies and simpler calculations are performed with existing data and maps from authorities, institutions and Uppsala municipality. The number of roof-mounted wind turbines required to cover the entire heat demand is highly dependent on the turbine effect and with a maximum power then up to 7190 wind turbines would be needed. The total area of solar collectors that would correspond to this is approximately 5000 m2. A borehole storage would need to require between 479 to 4793 boreholes, much depending on the heat conductivity of the rock and how far down it is possible to drill. The aquifer could generate a power of about 1000 kW, equivalent to slightly more than a third of the total demand. Finally, the possibility of a combined system with the appropriate energy solutions was obtained and a proposal for how it could be dimensioned. When assessing the environmental impact and suitability of the various solutions, we find that geothermal energy can pose a risk to the underlying groundwater source. Above all, the aquifer storage can be considered as quite unsuitable as the storage is based directly on the drinking water source.
18

Solenergi på Lappkärrsbergets studentbostäder : En studie om ekologisk och ekonomisk lönsamhet hos en solpanelsanläggning / Solar Power at Lappkärrsberget's Student Accommodations : A Study of Economic and Ecological Profitability of a Solar Panel Installation

Kaya, Dilan, Larsson, Marcus January 2017 (has links)
Syftet med denna rapport är att undersöka huruvida det skulle vara ekonomiskt och ekologiskt rimligt att installera en solpanelsanläggning på taken vid Lappkärrsbergets studentbostäder. Dessutom är syftet att undersöka skillnaderna mellan två olika system: ett där all producerad energi säljs till ett elbolag, och ett där energin används på plats med hjälp av ett energilagringssystem. Ekonomianalysen utförs genom att kontakta solpanels- och energilagringsentreprenörer för att få uppskattningar på grundinvesteringens storlek, samt intäkterna över tid. Solpanelsanläggningens slutliga värde beräknas sedan med nuvärdesmetoden. Ekologianalysen utförs genom en litteraturstudie av livscykelanalyser och ekologiska konsekvenser mäts helt i växthusgasutsläpp med koldioxidekvivalent som enhet. En kostnads-effekt-analys genomförs även för att illustrera korrelationen mellan anläggningens ekonomiska och ekologiska effekter. Undersökningen visar att en solpanelsanläggning vid Lappkärrsberget inte kommer löna sig ekonomiskt, med en förlust på 8 292 115 kronor vid försäljningsscenariot och 72 600 395 kronor vis lagringsscenariot. Undersökningen visar också att anläggningen lönar sig ekologisk, med en besparing i växthusgasutsläpp på cirka 38 %. / The purpose of this report is to examine whether it would be economically and ecologically sound to install a system of solar panels on the roofs of the student accommodations at Lappkärrsberget. The report also examines the differences between a system where all energy produced is sold to an energy company, and one where the energy is used on-site in combination with an energy storage system. The economic analysis is performed by contacting solar power and energy storage businesses to get estimates on the size of the initial investment and income generated over time. The final value of the solar panel installation is calculated using the net present value. The ecological analysis is performed as a literature survey of life cycle analyses of solar panel installations and ecological impact is measured entirely in greenhouse gas emissions, with carbon dioxide equivalent as the unit. A cost-effectiveness analysis is performed as to illustrate the correlation between the economic and ecological effects of the solar panel installation. In conclusion, it is shown that a solar panel installation on the roofs at Lappkärrsberget will not be a sound economic investment, reporting a loss of 8 292 155 SEK if the energy is sold, and 72 600 395 SEK if it is used on-site. It is also shown that a solar panel installation would be a sound investment ecologically with savings in greenhouse gas emissions of about 38 %.
19

Linbana som östlig tvärförbindelse : Förslag på linbana mellan Sickla och Ropsten / The New Eastern Cross-link : A suggestion for a cable car between Sickla and Ropsten

Storkaas, Lydia January 2017 (has links)
No description available.
20

Performance Metrics for Sustainability Value

Sundfors, David January 2016 (has links)
The trend that started with Green Building has moved on into Sustainable Building. But how do we know that something is really sustainable? This project started out with the intention to find a small set of performance indicators for commercial buildings, which could be continuously measured and monitored over time, which would give a good indication of the level of sustainability of the building and as such, and be presented as an additional part in a valuation. Since it has been shown several times over by now that properties that can prove they are sustainable generate a higher market price, these performance indicators would be interesting from the perspective of a valuation professional. In order to find these parameters, the project began with three of the international environmental certification systems and one Swedish system, to study which parameters are considered important in these systems. Following that study, surveys and interviews within the real estate business in Sweden provided an insight into how performance is measured today. Lastly, by combining those studies with a review of the sustainability information considered important by the Royal Institute of Chartered Surveyors (RICS) from a valuation professional’s point of view and an updated literature review, a simple set of indicators could indeed be identified. There is however, still a problem with defining their actual impact on market price. Other authors have come to the conclusion that although sustainability can be measured to some extent, incorporating that information into valuation of the property in a statistical secure way is not yet possible. We need to increase our knowledge about the performance of our built environment and the presented key performance indicators in this thesis would help us do just that. We can also see that real estate owners in many cases already gather much information about their buildings, but they lack the incentives to share that data with others. / <p>QC 20170124</p>

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