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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.
191

Miljöcertifiering av befintlig byggnad : Utredning om tillvägagångssätt och tidsåtgång enligt Miljöbyggnad 3.0 / Environmental Certification of a pre-existing building : An investigation regarding way of methods and time of work according to Miljöbyggnad 3.0

Jonsson, Thim January 2018 (has links)
Denna rapport utgör ett examensarbete vid Umeå Universitet. Målet med denna rapport är att visa val av metod, tillvägagångssätt och tidsåtgång enligt Miljöbyggnad för befintliga byggnader. Miljöbyggnad är ett certifieringssystem där indikatorer för energi, miljö och material undersöks. Klarar byggnaden kraven får den en Miljöbyggnadscertifiering. \\ \\ Miljöbyggnad startade redan 2003, vid dåvarande namn, Miljöklassad byggnad och var ett samarbete mellan kommun, företag och regering för en hållbar utveckling inom bygg- och fastighetssektorn. Detta var kopplat till de miljömål som regeringen satte upp 1999.\\ \\ De indikatorer som undersökts i detta arbete har varit de kopplade till energi och miljö. Enligt instruktionerna för Miljöbyggnad kan många av indikatorernas resultat redovisas genom simulerade värden eller uppmätta/beräknade värden. \\ De resultat som är kopplade till indikatorerna har undersökts genom mätning, beräkning och simulering då jämförelse mellan metoder har gjorts. \\ \\ Arbetet har resulterat i ett förslag om tillvägagångssätt där företaget i samband med en energideklaration kan göra en grov uppskattning huruvida en Miljöbyggnadsprocess kan göras. Visar byggnaden sig lämplig för en sådan certifiering är förslaget att insamling av nödvändig information om byggnaden sker i första steget. Det innefattar allt från ritningar av hela fastigheten till inventering av fastighetens interna laster. Vidare ska byggnadens energi- och miljödata simuleras för att kunna jämföras mot Miljöbyggnads krav. Detta tillvägagångssätt bedöms vara mest lämpligt för de flesta fastigheter.  \\ Det finns enklare sätt att bedöma vissa av indikatorerna men det kräver samtidigt att ett rum/lokal uppfyller vissa förutsättningar. / This report is a bachelor thesis at Umeå University. The purpose of this report is to show the choice of method, approach and timeframe according to the environmental building for existing buildings. \\ \\ Miljöbyggnad is a certification system in which indicators for energy, environment and materials are examined. If the building meets the requirements, it will receive an environmental certification. Miljöbyggnad started already in 2003, when it was called the Miljöklassad byggnad and was a cooperation between the municipality, companies and government for sustainable development in the construction and real estate sector. This was linked to the environmental goals set by the government in 1999. \\ \\The indicators investigated in this work have been linked to energy and the environment. According to the instructions for environmental construction, many of the indicators can be reported by simulated values or measured/calculated values. \\ The results associated with the indicators have been investigated by measurement, calculation and simulation where comparison of methods has been made. \\ \\ The work has resulted in a proposal for ways in which the company, in connection with an energy declaration, can make a rough estimate of whether an environmental construction process can be done. If the building is considered suitable for such certification, the proposal is that collection of necessary information about the building will take place in the first step. It includes everything from drawings of the entire property to inventory of the property's internal loads. Furthermore, the energy and environmental data of the building will be simulated in order to be able to compare against environmental building requirements. This approach is considered to be most appropriate for most properties. \\ There are easier ways to judge some of the indicators, but it also requires a room/officespace to meet certain conditions.
192

Energieffektivisering av flerbostadshus : Energibesparande åtgärder för Brf Lillåudden 3

Levay, Anders, Roos, Olof January 2018 (has links)
The European Union’s goal for year 2020 aims to reduce the greenhouse gases by 20 % compared to the levels of 1990. This goal can be reached by increasing energy efficiency and renewable energy sources by 20 %. In Sweden housing stands for 40 % of the total energy usage and in apartment buildings district heating is the most used way for heating and hot water. In this degree project two apartment buildings, connected by a garage, have been studied to see which solutions would yield a saving in both money and the environment. The building is heated using district heating and is ventilated through mechanical exhaust ventilation. Analyzing the current energy consumption and ventilation rates, two heat pump manufacturers was contacted to see what their systems could save in terms of energy. By recovering heat from the exhaust air with a heat pump the buildings can save both money and have a reduced impact on the environment. Having a demand-controlled ventilation in the garage would not give a large enough saving in energy to be worth the investment. The already scheduled fans have decreased their energy usage by half. However by having a demand-controlled ventilation in the garage it could reduce the harmful heavy metals that get released when cars drive in and out. By simply lowering the temperature in the garage from 15 °C to 10 °C could save about 12 500 sek/year in heating costs. The conclusion to this study is that using a heat pump to recover energy from exhaust air is an investment that will generate financial savings for the cooperative apartment and have a reduced negative impact on the environment.
193

Utvecklingen av energieffektiv teknologi i svenska datorcenter

Lundmark, Joakim January 2013 (has links)
This thesis investigate how energy efficient measures has spread throughout the data centers in Sweden. These questions are put up against a theoretical use of such concepts such as green IT, technological evolution, large technical systems and knowledge dissemination. These theories are used to answer the questions that are encountered during the study, such as how green IT is approached, how big of a role environmental thinking has had in the evolvement of these new technologies. The study has been conducted in a longitudinal manner, it is an observation of the phenomenon that is data centers over a longer period of time. 23 non structured interviews spanning over 27.5 hours of recorded material have been conducted alongside a study of archived material. An overview of what a data center represents is first presented and then a number of cases involving different companies is then presented to give examples of how different actors have managed their data centers. Through these examples it can be seen that working towards a more energy efficient market among data centers is something that has been going on for a long time and is gaining a lot of ground today. A lot of today’s focus is leaning towards how to use computer power as a method of becoming greener. A cyclical pattern of the large accumulation of computer power is also an important factor here were the large centralizations of computer power enables big actors to focus more on greening.
194

Energikartläggning av ett stort företag : Rutin för insamling av energidata, energianalys och åtgärdsförslag / Energy audit of a large company : Data collection, energy analysis and proposals of energy efficiency

Andersson, Sofia January 2018 (has links)
The EU directives of energy efficiency and transparency of sustainablework have recently been implemented in Swedish law. This requires largecompanies to report audits of their energy use and how they work withsustainability. Due to the recent requirements, many companies do not havea systematic method to collect and report the data needed. In this projectsuch a company in construction and residential development - VeidekkeSverige - has been examined and evaluated. The aim of the project has beento systemize the collection and compilation of data from the energy use ofVeidekke Sverige and perform an energy audit and report their greenhousegas emissions. The energy audit involves systematically mapping energyusage and making proposals for cost-effective measures to decrease energyuse. This has been made at a general level for the whole company andstudied in detail at one of the affiliated companies - Veidekke Prefab.The routine for the collection of energy data developed in this projectwas made with standardized surveys, adapted to the type of data requestedin any special case, from a variety of internal units at the company andexternal suppliers. The compilation of the surveys has been programmed inExcel. Although the routine for the collection and compilation of energydata has been standardized from previous implementations, unique manualchanges to the compilation file is still required for an upcoming year. Arecommendation is therefore to implement the developed routine at adigital platform, where surveys can be filled in online and then managedand compiled automatically at the platform. The energy survey of VeidekkeSweden shows that energy consumption in 2017 was about 50 GWh, of whichfuel accounts for 37%, electricity for 33% and gasoline for 25%. Thus,measures of energy efficiency should be done in the use of these threesources. The detailed energy audit of Veidekke Prefab shows that thecompany has a high power consumption of which half derives from theproduction, although, focus of the energy audit has been on ventilationand heating. The plant has two buildings for drying that are heated withdirectacting electric boilers which are recommended to be replaced by airheat pumps. In addition, the ventilation unit for the large buildingshould be replaced by a more modern unit with rotary heat recovery toreduce demand of district heating with about 20 %. Another feasiblemeasure is to replace the lighting to LED units, which would reduce energyconsumption by 6 %.
195

Invändig eller Utvändig tilläggsisolering av ett flerbostadshus- LCC analys av optimal isoleringstjocklekar : Fallstudie på Sicksackvägen 39 i Gävle

Dahir, Mohamed January 2017 (has links)
Stadsdelen Sätra som ligger 3 km norr om Gävle centrum uppfördes undermiljonprogrammet mellan 1960-1974. Det är enkelt och ta sig till och från Sätramed både fordon, cykel och till fots. AB Gavlegårdarna har tagit initiativ till attrenovera deras byggnadsbestånd som uppfördes under miljonprogrammet istadsdelen Sätra, däribland Sicksackvägen 39. Byggnaden har byggts 1969 ifunktionalistisk stil i närheten av Sätra Centrum.Syftet med denna studie var att undersöka den kostnadsoptimala isoleringstjocklenvid invändig eller utvändig tilläggsisolering av husets ytterväggar. Med hänsyn tillandra åtgärder som AB Gavlegårdarna vill genomföra vid renovering av denbefintliga byggnaden.För att genomföra denna studie har en okulärbesiktning, litteraturstudie,beräkningar, uppmätningar, undersökningar, samt energisimulering utförts. Därpåjämfördes lönsamheten vid tilläggsisolering med optimala isoleringstjocklekeninvändigt respektive utvändigt.Resultatet av denna studie visar att de komponenter i husets klimatskärm somläcker mest värme är ytterväggar och fönster. Med hänsyn taget till derenoveringsåtgärder som AB Gavlegårdarna ska genomföra blir den optimalaisoleringstjockleken invändigt är 45 mm och utvändigt 170 mm. Den åtgärd som germest lönsamhet är tilläggsisolering utvändigt med 170 mm mineralull i kombinationmed AB Gavlegårdarnas renoveringsåtgärder: fönsterbyte och uppgradering avventilationssystemet till FTX.
196

Energieffektivisering av en universitetsbyggnad genom att begränsa studenternas access / Energy efficiency of a University building by limiting the student’s access

Röring, Erik January 2017 (has links)
Idag består sektorn för bostäder och service för 40% av den totala energianvändningen i Sverige, där effektivisering av byggnaders energianvändning är en viktig process i utvecklingen mot förbättrad energiprestanda. Energieffektivisering är ett högaktuellt ämne och för att främja utvecklingen finns det uppsatta energipolitiska mål. Syftet med projektet var att studera den årliga energianvändningen i humanisthuset på campusområdet i Umeå och undersöka hur mycket energi som kan sparas genom att begränsa studenternas tillträde till studieytor under kvällar och helger. Akademiska Hus är ett av Sveriges största fastighetsbolag som förvaltar universitets- och högskolefastigheter belägna från Luleå i norr till Malmö i söder. Fastighetsbolaget är statligt ägt och känner därför ett särskilt ansvar att ligga i framkant gällande hållbar energikonsumtion. Energieffektiviseringsåtgärder och klimatoptimering är därför något som satsas mycket på vilket har lett till att de idag är ledande i frågan. Humanisthuset är beläget på Umeå universitet och har förutom lektionssalar och grupprum, fem öppna studieytor som undersöktes närmare i studien. Byggnadens årliga energibehov beräknades i två olika fall med simuleringsprogrammet IDA ICE. I första fallet antogs studenterna ha access till samtliga studieytor och i det andra fallet begränsades studenternas access till enbart två ytor. I de avstängda ytorna kunde belysning och ventilation minskas, till fördel för en energibesparing. Vid en jämförelse mellan de två fallen så beräknades det hur mycket energi som sparades årligen. Första fallet, i rapporten kallad referenssimuleringen, visade på att ventilationsaggregaten är mycket energieffektiva och att den största energiåtgången är i form av uppvärmning. Den specifika energianvändningen i byggnaden beräknades till 55,90 kWh/m2, 4,99 kWh/m2 och 12,11 kWh/m2 för energibärarna fjärrvärme, fjärrkyla och elektricitet. Jämförelsen mellan fallen visade att energianvändningen minskade med 10049 kWh per år, där minskad belysning var den största faktorn till besparingen. I procentuella termer minskade den totala energiförbrukningen med 0,7 procent.
197

Värmeförluster i ett prefabricerat småhus och dess inverkan på husets energiklass

Gustav, Fahlgren, Lilja, Johan January 2021 (has links)
In Sweden, the housing sector accounts for about 40% of the country's energy consumption. Theself-contained houses account for about 20% of this energy consumption (Energimyndigheten,2021). Boverket is the authority in Sweden that regulates the laws and regulations that affectenergy use (Boverket, 2016). In addition to Boverkets regulations, there are external organizationsthat drive development to minimize households' energy use (Feby, 2019). One of theseorganizations is FEBY, they have designed requirements that can be used as a complement to theBBR requirements. The organization has developed the parameter heat loss rate, which calculatesthe buildings heat loss.This study has been carried out in collaboration with the house manufacturer Jörnträhus AB. Thegoal of the work has been to develop a house that meets FEBY 18's requirements for heat loss rateand then verify the house's performance against Boverkets energy classification. The study wasbased on a reference house provided by Jörnträhus. The house was modeled in the energy programVIP-Energy and then analyzed. After the analysis, it was found that the reference house's VFTreaches 58.15 W / m2Atemp. Thereafter, the house was remodeled in VIP-Energy with changes tothe constructions and the ventilation system. With these changes, the VFT was calculated at 27.49W / m2Atemp and achieves the bronze level for FEBY 18.Finally, four simulations were performed to check the primary energy of the house during differentscenarios. All simulations were carried out in Skellefteå municipality but with different conditions.Two of the simulations were carried out at a location with open space and the other two simulationswere performed at a enclosed location with much shadow. In the different scenarios, the heatingand ventilation systems were varied. The simulations showed that wind and solar heat loads canhave a greater impact on primary energy than some technical solutions like heat recovery in theventilation.
198

Tillvaratagande av spillvärme i fjärrkylereturen : Energieffektivisering av Ulls Hus / Utilizing waste heat from the district cooling return

Hasth, Amanda, Modée, Amelia January 2020 (has links)
The Earth’s climate is getting warmer. Combustion of carbon dioxide is one of themain causes and results in increased levels of greenhouse gases that Earth’s vegetation is unable to carry, which ends up outside Earth’s natural cycle. In order to achieve an ecological sustainability, Sweden and EU has set climate and energy targets for 2020 and 2030, to encourage energy efficiency, energy savings and development of new and renewable energy sources. Akademiska Hus, is one of Sweden's largest property companies and their goal is to reduce the amount of purchased energy by 50% until 2025. This study was made in cooperation with Akademiska Hus and aims to investigate the possibilities of utilising waste heat from the district cooling return for Ulls Husby implementing a heat exchanger which preheats the supply air in the ventilation system for the building. The goal is to examine if the solution is realizable and profitable, and to create a basis for future implementation of heat recovery in several of Akademiska Hus's properties. Calculations regarding power and energy demands are carried out for the current ventilation system without preheating and with an implemented preheating. Seven different test scenarios were investigated to determine when the conditions are favorable for preheating. The payback method is applied to investigate if the implementation is economically profitable. The results show that the purchased energy can be decreased by 1332 kWh for Ulls Hus by preheating the air during the investigated period between 15th October 2018 and 14th April 2019. Preheating decreases the number of power peaks higher than 25 kW in the ventilation system from 160 to 5 peaks. The reduction in energy and power demand is not considered economically profitable with a payback time of 309 years. Optimizing the operation strategy for the ventilation system to eliminate the power demand that occurs during the daily start of the system can decrease the purchased energy without preheating by 1 486 kWh, which correspond to 66%.With preheating the reduction can be additional 816 kWh to the results of preheating. This, as a suggestion, can be done by commissioning the heatexchanger before the rest of the ventilation system starts. The results for the four of the seven test scenarios that including lower temperature efficiency and 24-hour operation, alone or combined with each other and with a regulated supply air, show a larger reduction of purchased energy andthat an implementation can be considered economically profitable with shorter payback times. The four scenarios show a reduction with 62 630 kWh to 122 160 kW hand a pay back time half as short as the technical life expectancy which is considered economically profitable.
199

Utvärdering av ventilationsflöde och luftkvalitet i bostadsgarage : En mätstudie och utformning av ett verktyg för framtida projekt

Andersson, Frida January 2020 (has links)
Parking garages are often ventilated in accordance with SBN minimum requirements, which specify an extract air flow rate of 0.9 l/s, m2 for residential parking garages and 1.8 l/s, m2 for public parking garages. It has recently been observed that fan units in many cases are overdimensioned and as a result often operate at low flow rates and rarely need to operate at full capacity. Oversized air handling systems create an excessively high demand for energy which raises overall operation costs. The aim of this master’s thesis is to investigate if the air flow in residential parking garages can be reduced while avoiding excess levels of pollution and maintaining an acceptable building moisture level. Furthermore, an excel macro was created in order to facilitate a more streamlined approach for future projects. The function of the macro was to simplify the process of determining the dimensions of ventilationsystems. Two residential parking garages with different types of air handling units were compared by measuring pollution contents in the air as well as extract air flow rate. Additionally, simulations were carried out for three different scenarios where the air flow was varied. The purpose of the simulations was to examine the energy-saving benefits of lower airflows compared to the current ventilation flow rate. Based on measurement data and simulations it can be concluded that the exhaust air flow for the investigated parking garages can be reduced to 0.2 l / s, m2 without reaching excess levels of pollution or allowing unacceptable moisture levels to develop. However, it is important that the air handling unit can operate at higher air flows in order to vent temporarily high peak concentrations. Furthermore, it should be noted that the pollution levels were consistently kept low and only a few peak concentrations were registered. This was to some extent not an unexpected result. High peak concentrations can be registered in a misrepresentative fashion. For example, if a car starts near the gas sensor it can cause a high peak concentration to be registered. Upon validation of the excel macro used, it is clear that the results correspond well with the above-mentioned measurements. Further studies can be done however, in order to obtain even more conclusive results.
200

Energikartläggning av hotellbyggnad med byggår 2016 och effektivisering av ventilation i IDA-ICE / Energy evaluation of hotel building built 2016 and energy efficiency of ventilation in IDA-ICE

Forslund, August January 2020 (has links)
The main purpose of this thesis was to evaluate the energy use and the potential for energy savings in the ventilation for a hotel building that has been preliminary certified in the Swedish environmental assessment method Miljöbyggnad. In the preliminary certificate the building received the certificate SILVER for the energy use. This certificate needs to be verified in order to acquire the final certificate. The energy use was determined with data from energy meters and statistics from the energy provider. The potential for energy savings in the ventilation was evaluated by analyzing the effects of air flows, room temperature and supply temperature on the energy use and the room climate with the help of the simulation program IDA-ICE. The results show that the energy use in the building is 119 kWh/(m2, year), which equals the certificate BRONS in Miljöbyggnad. The certificate for SILVER will not be achieved. The biggest energy consumers are the heating system, the hot water system and the cooling system. They stand for 36, 21 and 19 percent of the total energy use, respectively. With energy savings measures in the ventilation the energy use can be reduced by 8 kWh/(m2, year). This would mean that the energy use can be reduced to 110 kWh/(m2, year). The building would still receive the certificate for BRONS. The energy savings, however, would be achieved by using a lower supply temperature, minimum air flows (0,1 l/(s, m2)) when rooms are not used as well as decreasing the time schedule for the ventilation by two hours and allowing the maximum temperature to rise by 0,5 degrees Celsius. This also resulted in a higher temperature in the conference rooms, where the temperature could reach up to 24,2 degrees Celsius in winter and 24,5 degrees Celsius hot summer days.

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