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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.
171

Förhållandet av energianvändning i en byggnads livscykel : Med hänsyn till nyreglerade krav i BBR 29 / The relationship of energy use in a building’s life cycle according to regulations in BBR 29

Shaba, Sanna, Falk, Rikard January 2021 (has links)
Purpose: With the help of the stricter requirements in the National Board of Housing, Building and Planning's building regulations, knowledge regarding energy consumption must be highlighted, in order to have knowledge of at what stage more focus needs to be placed on further reducing energy use. Method: The data required to perform calculations will be retrieved from case study, document analysis and literature study. Findings: The report's analysis shows that despite stricter energy requirements in BFS 2011: 6, it has no major impact on an energy ratio during a building's life cycle of 50 years.The results show that the stricter requirements for BFS 2011:6 chapter 9 are on the right track to reduce energy consumption over a period of 50 years. Implications: The survey shows that stage B1-7 still accounts for most of the energy use in a building's life cycle. It also shows that the National Board of Housing, Building and Planning is on the right track with the regulations made in BFS 2011: Chapter 6. The results also indicate that further efficiency is possible, and that research can be done on this by testing new technologies and materials in a building. Limitations: The lifespan of a building is divided into three different stages, theconstruction stage, the use stage and the final stage. This work is limited to the first two stages and will therefore not consider the final stage. Keywords: BBR, Energy, Energy consumption, Energy losses, Energy use, Environmental impact, Life cycle analysis, Sustainable construction / Syfte: Med hjälp av de skärpta kraven i Boverkets byggregler har kunskap och förståelse gällande energiåtgång lyfts fram, för att vidare ha kunskap om i vilket skede mer fokus behöver läggas för att ytterligare minska på energianvändningen. Metod: Energiberäkningar har genomförts för att kunna besvara målet. Den data som krävs för att genomföra beräkningar har hämtats från fallstudie, dokumentanalys och litteraturstudie. Resultat: Rapportens analys visar att skärpta energikrav i BFS 2011:6 inte har någonstörre påverkan i ett energiförhållande under en byggnads livscykel på 50 år.Resultatet visar att de skärpta kraven på BFS 2011:6 kap 9 är på rätt spår för att minska energiåtgången under en tidperiod på 50 år. Konsekvenser: Avslutad undersökning visar att användningsstadiet, B1-7, fortfarandestår för majoriteten av energianvändningen i en byggnads livscykel och att Boverket är på rätt spår med de regleringar som gjorts i BFS 2011:6 kap 9. Resultatet tyder även på att ytterligare effektivisering är möjlig och att framtida undersökningar kan göras inomdetta område genom att testa nya tekniker och material i en byggnad.  Begränsningar: En byggnads livslängd är indelad i tre olika skeden, byggskedet, användningsskedet och slutskedet. Detta arbete begränsar sig till de två första skedenaoch tar därmed inte hänsyn till slutskedet. Nyckelord: BBR, Boverkets byggregler, Byggnadslivscykel, Energi, Energianvändning, Energiförbrukning, Energiförluster, Energiåtgång, Hållbart byggande, Klimatpåverkan, LCA, Livscykelanalys, Miljöpåverkan, Nollenergibyggnad, Nollenergihus
172

Assessment of the factors that influence firewood use among households in Ga-Malahlela Village, Limpopo Province

Masekela, Mahlodi Esther January 2019 (has links)
Text in English with abstracts in English, Sepedi and Venda / Access to firewood and other affordable energy sources is essential to the livelihoods of rural households in developing countries. Studies have been conducted to understand the reasons behind an extensive reliance on firewood in rural areas, especially in developing countries, despite improved electrification rates and a number of government policies introduced to encourage rural households to switch from traditional to modern fuels. This study aimed at assessing and thus understand the factors influencing the use of firewood by households in Ga - Malahlela village in Limpopo Province. Limited research has been conducted on firewood use, subsequent to improved electrification in rural areas in South Africa, hence it was to shed light on this little-explored subject on which the study was carried out. The assessment was based on household demographics and household energy use patterns, with a structured questionnaire being utilised to arrive at a detailed understanding of the factors that drive firewood use. It was established that firewood was still used to a significant degree, to satisfy household energy needs such as cooking, water heating and space heating. This was mainly due to the socioeconomic status of households. Socio-economic factors such as income, education level, household size and preference were found to be the factors exerting the greatest influence on the use of firewood among households in the study area. Psychological variables and the geographical location of the study area were also shown to promote the use of firewood. The study further revealed that, as indicated in the reviewed literature, households in the study area fuel stack and do not ascend the energy ladder. The reviewed literature further indicated that not all factors have equivalent significance in determining the behaviour and pattern of household energy use. This indicates that energy sources such as firewood are not completely discarded but are instead used in conjunction with modern energy sources such as electricity. In conclusion, this study established that despite the availability of electricity, as a result of poverty and the lack of free basic services such as free basic electricity, reliance on firewood in rural areas will continue. / Go hwetša dikgong le methopo ye mengwe ya dibešwa tšeo di rekegago go bohlokwa go mekgwa ya malapa a dinagamagaeng go hwetša dilo tše bohlokwa tša bophelo dinageng tšeo di hlabologago. Dithutelo di phethagaditšwe go kwešiša mabaka ao a thekgago kholofelo go dikgong mafelong a dinagamagaeng a dinaga tšeo di hlabologago le ge go na le ditekanyo tše di kaonafaditšwego tša tlhagišo ya mohlagase le palo ya melaotshepetšo ya mmušo yeo e tsebišitšwego go tutuetša malapa a dinagamagaeng go fetoga go tloga go dibešwa tša sekgale go iša go tša sebjale. Thutelo ye e ikemišeditše go lekola ka gona go kwešiša mabaka ao a huetšago malapa a Motsaneng wa Ga-Malahlela ka Profenseng ya Limpopo go diriša ya dikgong. Dinyakišišo tše lekantšwego di phethagaditšwe ka ga tirišo ya dikgong ka morago ga tlhagišo ya mohlagase yeo e kaonafaditšwego mafelong a dinagamagaeng ka Afrika Borwa, gomme e be e swanetše go fa tshedimošo ka ga hlogotaba yeo e hlohlomišitšwego gannyane gore thutelo ye e phethagatšwe. Tekolo ye e theilwe go dipalopalo ka ga malapa setšhabeng le mekgwa ya malapa ya go dirišwa dibešwa, ka go diriša lenaneopotšišo leo le beakantšwego gore go fihlelelwe kwešišo ye e hlalošago ka botlalo mabaka ao a hlohleletšago tirišo ya dikgong. Go lemogilwe gore dikgong di sa dirišwa ka bontši bjo bo bonagalago go kgotsofatša dinyakwa tša malapa tša enetši tše bjalo ka go apea, go ruthetša meetse le go ruthetša lefelo. Se se be se swanela gagolo ka lebaka la boemo bja ka moo ekonomi e amago tšwelopele ya malapa. Mabaka a ka moo ekonomi e amago tšwelopele ya setšhaba a go swana le ditseno, boemo bja thuto, bogolo bja lelapa le tšeo di ratwago go hweditšwe go ba mabaka ao a hlohleletšago khuetšo ye kgolokgolo go tirišo ya dikgong gare ga malapa thutelong ye. Dielemente tšeo di ka fetolwago le lefelo tikologong ye e itšeng tša thutelo le tšona di bontšhitšwe go godiša tirišo ya dikgong. Thutelo ye gape e utollotše gore, bjalo k age go šupilwe dingwalong tšeo di lekotšwego, malapa a lefelong la thutelo a latela mekgwa ya dibešwa tša mehutahuta gomme ga a latele manamelo a enetši. Dingwalo tšeo di lekotšwego di laeditše go ya pele gore ga se mabaka ka moka ao a nago le bohlokwa bjo bo lekanago go šupeng boitshwaro le mokgwa tša tirišo ya enetši ka malapeng. Se se šupa gore methopo ya enetši ye bjalo ka dikgong ga se ya tlogelwa ka gohlegohle eupša e dirišwa mmogo le methopo ya sebjale ya enetši ye bjalo ka mohlagase. Go ruma, thutelo ye e utollotše gore le ge go na le mohlagase, ka lebaka la bohloki le tlhaelo ya ditirelo tša motheo tša mahala tše bjalo ka mohlagase wa motheo wa mahala, kholofelo go dikgong dinagamagaeng e tlo tšwela pele. / U swikelela khuni na zwiṅwe zwiko zwa fulufulu zwine zwa swikelelea ndi zwa ndeme kha u tsireledza zwo teaho zwa vhutshilo kha miṱa ya vhupo ha mahayani kha mashango o no khou bvelelaho. Ngudo dzo farwa u itela u pfesesa zwiitisi zwa u ḓitika zwihulwane nga khuni kha vhupo ha mahayani kha mashango ane a khou ḓi bvelela zwi si na ndavha na u khwiniswa ha u dzheniswa ha muḓagasi na tshivhalo tsha mbekanyamaitele dza muvhuso dzo ḓivhadzwaho u ṱuṱuwedza miṱa ya vhupo ha mahayani u bva kha u shumisa zwivhaswa zwa kale u ya kha zwa ano maḓuvha. Ngudo iyi yo livhiswa kha u asesa na u pfesesa zwiṱaluli zwine zwa ṱuṱuwedza u shumiswa ha khuni nga miṱa ya Muvhunduni wa Ga-Malahlela Vunduni ḽa Limpopo. Ṱhoḓisiso dzi si nngana dzo itwa nga ha u shumiswa ha khuni hu tshi tevhela u dzheniswa ha muḓagasi vhuponi ha mahayani Afurika Tshipembe, ho vha u bvisela khagala nga ha zwiṱuku zwo wanululwaho kha thero heyi ye ngudo ya i bveledzisa. U linga ho vha ho ḓisendeka nga ngudamirafho ya miṱa na kushumisele kwa fulufulu miṱani, hu na mbudzisombekanywa dzo dzudzanywaho dzo shumiswaho u swikelela kha u pfesesa nga vhuḓalo zwiṱaluli zwine zwa ta u shumiswa ha khuni. Ho dzhielwa nṱha uri khuni dzi kha ḓi shumiswa nga maanḓa u ḓisa ṱhoḓea dza fulufulu miṱani u fana na u bika, u vhilisa maḓi na u dudedza vhudzulo. Hezwi zwo tea nga maanḓa kha vhuimo ha matshilisano a zwa ikonomi miṱani: zwiṱaluli zwa ikonomi ya matshilisano zwi ngaho sa mbuelo, vhuimo ha pfunzo, vhuhulu ha muṱa na zwo no takalelwa ho wanwa uri ndi zwiṱaluli zwine zwa shumisa ṱhuṱhuwedzo khulwane ya u shumiswa ha khuni vhukati ha miṱa ya vhupo ha ngudo. Variabuḽu dza saikhoḽodzhikhaḽa na vhupo ha ḓivhashango zwa vhupo ha ngudo zwo sumbedziswa u ṱuṱuwedza u shumiswa ha khuni. Ngudo yo isa phanḓa na u wanulusa uri, sa zwo sumbedziswaho kha maṅwalwa o sedzuluswaho, miṱa kha vhupo ha ngudo i kuvhanganya fulufulu ngeno hu sina u gonya ha tshanduko ya kushumisele kwa fulufulu. Maṅwalwa o sedzuluswaho o sumbedzisa a tshi i sa phanḓa uri a si zwiṱaluli zwoṱhe zwine zwa vha na ndeme i linganaho kha u ta vhuḓifari na kushumisele kwa fulufulu miṱani. Hezwi zwi sumbedza uri zwiko zwa fulufulu zwi ngaho sa khuni a zwo ngo laṱelwa kule tshoṱhe fhedzi zwi shumiswa zwo ṱanganyiswa na zwiko zwa fulufulu zwa ano maḓuvha zwi ngaho sa muḓagasi. Ri tshi pendela, ngudo iyi i ta uri na musi muḓagasi u hone, nga nṱhani ha vhushayi na ṱhahelelo ya tshumelo dza muḓagasi wa mahala wa mutheo u fana na muḓagasi wa mahala wa mutheo, u ḓitika nga khuni vhuponi ha mahayani hu ḓo ḓi bvela phanḓa. / Department of Environmental Science / M.A. (Environmental Science)
173

Assessing the potential of fuel saving and emissions reduction of the bus rapid transit system in Curitiba, Brazil

Dreier, Dennis January 2015 (has links)
The transport sector contributes significantly to global energy use and emissions due to its traditional dependency on fossil fuels. Climate change, security of energy supply and increasing mobility demand is mobilising governments around the challenges of sustainable transport. Immediate opportunities to reduce emissions exist through the adoption of new bus technologies, e.g. advanced powertrains. This thesis analysed energy use and carbon dioxide (CO2) emissions of conventional, hybrid-electric, and plug-in hybrid-electric city buses including two-axle, articulated, and biarticulated chassis types (A total of 6 bus types) for the operation phase (Tank-to-Wheel) in Curitiba, Brazil. The systems analysis tool – Advanced Vehicle Simulator (ADVISOR) and a carbon balance method were applied. Seven bus routes and six operation times for each (i.e. 42 driving cycles) are considered based on real-world data. The results show that hybrid-electric and plug-in hybrid-electric two-axle city buses consume 30% and 58% less energy per distance (MJ/km) compared to a conventional two-axle city bus (i.e. 17.46 MJ/km). Additionally, the energy use per passenger-distance (MJ/pkm) of a conventional biarticulated city bus amounts to 0.22 MJ/pkm, which is 41% and 24% lower compared to conventional and hybrid-electric two-axle city buses, respectively. This is mainly due to the former’s large passenger carrying capacity. Large passenger carrying capacities can reduce energy use (MJ/pkm) if the occupancy rate of the city bus is sufficient high. Bus routes with fewer stops decrease energy use by 10-26% depending on the city bus, because of reductions in losses from acceleration and braking. The CO2 emissions are linearly proportional to the estimated energy use following from the carbon balance method, e.g. CO2 emissions for a conventional two-axle city bus amount to 1299 g/km. Further results show that energy use of city bus operation depends on the operation time due to different traffic conditions and driving cycle characteristics. An additional analysis shows that energy use estimations can vary strongly between considered driving cycles from real-world data. The study concludes that advanced powertrains with electric drive capabilities, large passenger carrying capacities and bus routes with a fewer number of bus stops are beneficial in terms of reducing energy use and CO2 emissions of city bus operation in Curitiba.
174

Byggnadsutformning för ett framtida varmare klimat : Klimatscenariers påverkan på energianvändning och termisk komfort i ett flerbostadshus och alternativa byggnadsutformningar för att förbättra resultatet / Building design for a future warmer climate : Climate scenarios impact on energy demand and the thermal comfort in an apartment building and alternative constructions to improve the results

Monfors, Lisa, Morell, Corinne January 2020 (has links)
När byggnader projekteras används klimatfiler från 1981-2010 för att dimensionera konstruktionen och energisystemet. Detta leder till att byggnader dimensioneras för ett klimat som varit och inte ett framtida klimat. SMHI har tagit fram olika klimatscenarier för framtiden som beskriver möjliga utvecklingar klimatet kan ta beroende på fortsatt utsläpp av växthusgaser. Dessa scenarier kallas för RCP (Representative Concentration Pathways). I denna studie används två olika klimatscenarier, RCP4,5 och RCP8,5. Siffran i namnet står för den strålningsdriving som förväntas uppnås år 2100. I RCP4,5 kommer medelårstemperaturen öka med 3 °C fram till år 2100 jämfört med referensperioden 1961-1990.  För samma tidsperiod sker en ökning på 5 °C enligt RCP8,5.  Ett flerbostadshus certifierad enligt Miljöbyggnad 2.2 nivå silver placerat i Vallentuna i Stockholms län används i denna studie som referensbyggnad. Byggnaden simuleras i programmet IDA ICE där den utsätts för RCP4,5 och RCP8,5. Resultatet visar att byggnaden inte skulle klara av kraven för Miljöbyggnad 2.2 gällande termiskt klimat sommar i något av de två klimatscenarierna. De operativa temperaturerna blir för höga i byggnaden utan att tillsätta komfortkyla.  Byggnaden ändras för att se vilka faktorer som kan förbättra resultatet gällande det termiska klimatet. Resultatet visar att värmelagringsförmåga hos byggmaterial och solavskärmning har störst påverkan på det termiska klimatet.  I studien gjordes flertal olika kombinationer av byggnadsutformningar. Enbart kombinationen av en tung stomme av betong tillsammans med fönster med lägre g-värde klarar kraven för Miljöbyggnad 2.2 i RCP4,5 och RCP8,5 utan komfortkyla. Kombinationen får lägst energianvändning i RCP8,5 av de olika kombinationerna som testats i studien.  En kombination av tung stomme av KL-trä med lågt U-värde, fönster med lägre g-värde och komfortkyla får lägst energianvändning i grundklimatet och RCP4,5 av de olika kombinationerna som testats i studien trots användningen av komfortkyla.  Frågan om vilket alternativ som är bäst ur ett hållbarhetsperspektiv är svårt att svara på. Det finns många aspekter som behöver tas i hänsyn till som byggnadens totala klimatavtryck både i tillverkning och användning. Oavsett val av konstruktion är det viktigt att projektera för att komfortkyla och solavskärmning skall kunna appliceras när ett varmare klimat råder. / When buildings are designed climate files from 1981 to 2010 are used to construct the building and its energy system. This leads to building being designed to a climate that has been and not to a future warmer climate that will come. SMHI has developed different climate scenarios for the future that describe different paths the climate can take depending on continued emissions of greenhouse gas. This climate scenarios are called RCP (Representative Concentration Pathways) In this study two of the climate scenarios, RCP4,5 and RCP8,5 are used. The number in the name stands for the radiation forcing that is expected in the year 2100.  In RCP4,5 the mean average air temperature will increase with 3 °C until year 2100 compared to the reference period 1961-1990. In the same time period RCP8,5 will increase with 5 °C.  An apartment building certified according to Miljöbyggnad 2.2 level silver placed in Vallentuna, Stockholms län is used as a reference building. The building is simulated through the simulation software program IDA ICE where it´s exposed to RCP4,5 and RCP8,5. The results demonstrate that the reference building would not meet Miljöbyggnad 2.2 requirement in the indicator about thermal comfort during summer. The operative temperature in the building is too high unless comfort cooling is used.  The design of the building changes to see what factors can improve the results regarding the thermal comfort. The results demonstrate that thermal conductivity and solar shading has the greatest impact on thermal comfort.  In this study several combinations of different building designs were made. Only the combination of a concrete frame with windows with low g-value met the requirement of Miljöbyggnad 2.2 regarding the thermal comfort during summer without using comfort cooling in RCP4,5 and RCP8,5. The combination had the lowest energy demand in RCP8,5 of all the combinations tested in the study.  A combination of cross laminated wood frame with low U-value, windows with low g-value and comfort cooling had the lowest energy demand in the original climate file and RCP4,5 despite the use of comfort cooling.  The questing about which building construction is the best from a sustainable perspective is difficult to answer. To answer that question the building´s total climate footprint in both production and use must be calculated. Regardless of the choice of building construction it is important to have in mind when designing a building that comfort cooling and solar shading should be easily applied when a warmer climate will prevail.

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