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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.
1

GIS-Based Analysis of Local Climate Zones in Denton, Texas

Michel, Daniel 12 1900 (has links)
This study implemented a GIS-based analysis of local climate zones (LCZ) in Denton, TX with data sets from 2009, 2011, 2015, and 2016. The LCZ scheme enables evaluation of distinct regions' thermal characteristics with greater granularity than conventional urban-rural dichotomies. Further, the GIS-based approach to LCZ mapping allows use of high-resolution lidar data, the availability of which for the study area enabled estimation of geometric and surface cover parameters: height of roughness elements, sky-view factor, and building surface fraction. Pervious surface fraction was estimated from National Landcover Database impervious imagery. A regular grid was used to estimate per-cell mean values for each parameter, and with a decision-making algorithm (if/then statements) two maps were produced (2011 and 2015) and six LCZ identified in each: LCZ 6 (open low-rise), LCZ 8 (large low-rise), LCZ 9 (sparsely built), LCZ A (dense trees), LCZ B (scattered trees), and LCZ C (bush/scrub). Post-processing was carried out to ensure identified zones met the spatial minimum for qualification as LCZ. Landsat Collection 2 Level 2 surface temperature products from various seasons of 2011 and 2015 were acquired to examine LCZ thermal differentiability, and preliminary surface urban heat island intensity values were estimated. Particular attention was afforded to issues regarding data quality and classifier threshold adjustment.
2

Some Comparisons of Thermal Energy Consumption in a Temperature Versus a Subtropical Zone

Buljan, Jakov, Bosnić, M., Král’, I. 28 June 2019 (has links)
Content: The aim of this desk study is to compare consumption of thermal energy in temperate vs. (sub)tropical climate for two representative processes: float heating (bating and dyeing) and chamber drying, with the view of contributing towards overall assessment of thermal energy consumption for tanneries operating under rather different conditions. The energy consumption is calculated for 1 t of wet salted hides and assuming that 1000 kg of wet salted weight corresponds to 1100 kg of pelt weight containing 838 kg of water and 262 kg of collagen subsequently segregated into grain leather and usable splits. Float rates (200% on pelt/shaved weight), average inlet water temperatures (15 oC vs. 25 oC), process float temperatures for bating (35 oC) and dyeing (60 o C) have been defined. Similarly, for computation of thermal energy for chamber drying, identical initial (45 %) and target leather humidity (20 %) are set and average respective fresh air temperature (15 oC vs. 30 oC) and fresh air relative humidity (50% vs. 70%) estimated and operating conditions such as exhaust air temperature and relative humidity defined. Based on such parameters and assumptions, specific ratios for thermal energy consumption for float heating (bating & dyeing) and for chamber drying have been calculated and comparisons made; the results might not quite coincide with common perceptions. The energy needs computed are net amounts, i.e. regardless of the source and without taking into account any losses and disregarding energy consumption for ambient heating and/or cooling. Thus, the total energy needs are much higher. The ratios computed for grain leather are valid for split leather as well. However, if the solar energy is used to support water heating, the conditions in the tropic zone are substantially more favourable, due to higher insolation and higher efficiency factor (i.e. difference of the final vs. inlet water temperature). Take-Away: Based on such parameters and assumptions, specific ratios for thermal energy consumption for float heating (bating & dyeing) and for chamber drying have been calculated and comparisons made; the results might not quite coincide with common perceptions. However, if the solar energy is used to support water heating, the conditions in the tropic zone are substantially more favourable, due to higher insolation and higher efficiency factor (i.e. difference of the final vs. inlet water temperature).
3

Evaluating Effects of Urban Growth Within the Greater Salt Lake Area on Local Meteorological Conditions Using Urban Canopy Modeling

Smithson, Corey L. 09 June 2023 (has links) (PDF)
The increasing urbanization of the greater Salt Lake City area (GSLA) has contributed to the development of an urban canopy over this area. This canopy refers to the effects of building profiles, varying land surface properties and anthropogenic heating on local meteorological conditions including temperature, humidity, and wind velocity. Urban Canopy Models (UCMs) can be used to represent these characteristics on a mesoscale without needing to develop models accounting for effects of individual buildings. One method used to classify urban areas are Local Climate Zones (LCZs), which assign different properties to different types of urban areas. A baseline model that represents current GSLA conditions was developed using a series of sensitivity studies, which focused on the effects of mesh resolution, land surface models, UCMs, anthropogenic heating rates and LCZ urban classifications. The baseline model was validated using measured meteorological data. Four urban growth scenarios were compared to this baseline model to evaluate the effects of future growth on local 2-meter air temperatures, 2-meter relative humidity, and 10-meter wind speed. Results showed increased urban density did not affect daytime temperatures within the GSLA, but did significantly increase local nighttime temperatures. The effects of anthropogenic heating rates were most noticeable during early nighttime hours. Also, increased urbanization affected local temperatures, but did not appear to have "downwind" effects on other areas. A User Guide documenting the modeling approach was developed to support additional studies.
4

Impact of Ice Storage on Electrical Energy Consumption in Large and Medium-sized Office Buildings in Different Climate Zones

Sehar, Fakeha 10 October 2011 (has links)
Cooling demand constitutes a large portion of total electrical demand for office buildings during peak hours. Deteriorating load factors, increased use of more inefficient and polluting peaking units are the aftermaths of growth in peak demand challenging energy system efficiency and grid reliability. Ice storage technology can help shift this peak cooling demand to off-peak periods. Ice storage reduces or even eliminates chiller operation during peak periods. The objective of the research is to analyze the chiller energy consumption of conventional non-storage and ice storage cooling systems for large and medium-sized office buildings in diverse climate zones. The research also quantifies the peak energy savings as a result of ice storage systems. To accomplish the thesis objectives the Demand Response Quick Assessment Tool (DRQAT) has been used to model and simulate large and medium-sized office buildings in diverse climate zones with non-storage and ice storage cooling systems. Demand Response Quick Assessment Tool (DRQAT) has been developed by LBNL's Demand Response Research Center. It is based on the most popular features and capabilities of EnergyPlus and is downloadable from [1]. The construction and weather files in DRQAT have been modified to incorporate construction standards and weather data for the cities representing the diverse climate zones. The ice storage system's operating and control strategies investigated include full storage and partial storage with storage priority and chiller priority. Research findings indicate that chiller energy consumption for non-storage and ice storage systems depends highly on climatic conditions. The climate zones with hot summers as well as small day and night temperature variations show higher chiller energy consumption. The marine climate zone has the lowest chiller energy consumption. The cold/humid climate zone has higher chiller energy consumption than the cold/dry and very cold climate zones. The cold/dry and very cold climate zones have comparable chiller energy consumption. The research findings will help utilities and building owners to quantify the benefits of installing ice storage systems in office buildings located in different climate zones. / Master of Science
5

Microbial assemblage in grapevine's phyllosphere : who is the driver ? / Assemblage microbien dans la phyllosphère de la vigne : qui est le pilote ?

Singh, Prashant 30 November 2018 (has links)
Vitis vinifera subsp. vinifera L., les principales espèces de raisins sont cultivées pour la production de fruits et la production de vin dans le monde est un hôte naturel d'une grande variété de micro-organismes procaryotes et eucaryotes qui interagissent avec la vigne, ayant des effets bénéfiques ou phytopathogènes. Ils pourraient également jouer un rôle majeur dans le rendement des fruits, la qualité du raisin, la protection des plantes et, finalement, dans le modèle de la fermentation du raisin et la production de vin. La phyllosphère (constituée des parties aériennes de la plante) est l'un des habitats microbiens les plus répandus sur terre et est un milieu assez négligé, en particulier dans les vignes et de nombreuses questions liées à cet habitat microbien sont toujours sans réponse.Cette thèse est un effort pour répondre à une question fondamentale en écologie microbienne: quels sont les facteurs qui déterminent le microbiome dans la phyllosphère de la vigne? Les communautés microbiennes de la phyllosphère (PMCs) vivent à l'interface plante-climat et sa capacité à s'établir, prospérer et se reproduire sur la surface des feuilles ou des fruits dépend de plusieurs caractéristiques fonctionnelles microbiennes, comme la capacité de se fixer sur la cuticule et d'utiliser la foliaire. nutriments ainsi que les conditions climatiques dominantes comme la température, l'humidité de l'air et la pluie. La chimie des feuilles ou des fruits, la physiologie et la structure morphologique diffèrent selon le génotype et l'espèce puisque tous ces traits ont une base génétique, et cette variation peut mener à une combinaison différente d'assemblage de PMC parmi les génotypes de plantes. Ainsi, le premier objectif de notre travail était d'évaluer les impacts des cultivars de vigne (variétés de Vitis vinifera L) et des espèces de vigne (espèces Vitis entièrement différentes) sur l'assemblage du microbiome dans la phyllosphère à un endroit géographique particulier (pour minimiser les effets environnementaux) . Plus tard, les impacts de certains cultivars et terroirs de vigne commercialement importants (représentés par trois zones climatiques françaises) ont également été évalués et comparés. Les impacts de la saison et des organes extérieurs de la plante (feuilles et baies) sur la structuration des taxons microbiens dans la phyllosphère ont également été évalués et présentés dans ce travail. De plus, des impacts spécifiques à l'espèce sur le microbiome de la phyllosphère ont également été testés et représentés.Dans l'ensemble, notre étude a évalué et comparé les nombreuses facettes des facteurs qui peuvent influencer structure du microbiome dans la phyllosphère avec un accent particulier sur la pression de sélection relative exercée par le génotype de la vigne et son interaction avec différentes conditions climatiques (ou terroir), ce qui peut améliorer nos chances de trouver des gènes contrôlant les PMCs sur la phyllosphère. les gènes sont réellement importants dans des environnements réalistes et probablement ces gènes nous donneraient de nouvelles idées pour la sélection de nouveaux cépages sains présentant de meilleurs caractères sur leur phyllosphère. De plus, considérant que les PMC végétales jouent un rôle crucial dans la santé et la forme des plantes car elles peuvent moduler la susceptibilité foliaire aux infections, cette étude pourrait également être utile pour développer des méthodes de biocontrôle innovantes et naturelles ou phytostimulation contre les pathogènes de la vigne. de variétés résistantes innovantes. / Vitis vinifera subsp. vinifera L., the main grape species are grown for fruit and wine production over the world is a natural host of a wide variety of prokaryotic and eukaryotic microorganisms that interact with grapevine, having either beneficial or phytopathogenic effects. They could also play a major role in fruit yield, grape quality, plant protection and, ultimately, in the pattern of grape fermentation and wine production. Phyllosphere (consists of the aerial parts of the plant) is one of the most prevalent microbial habitats on earth and is quite a neglected milieu, especially in grapevines and many questions related to this microbial habitat, are still unanswered.This thesis is an effort to answer a very fundamental question in microbial ecology- what are the drivers that shape the microbiome in the grapevine's phyllosphere? The phyllosphere microbial communities (PMCs) live at the plant-climate interface and its ability to establish, thrive and reproduce on the leaf or fruit surface depends on several microbial functional traits, such as the ability to attach to the cuticle and to use the foliar nutrients as well as well as to the prevailing climatic conditions like temperature, air humidity and rain. Leaf or fruit chemistry, physiology, and morphological structure differ among plant genotype and species as all these traits have a genetic basis, and this variation may lead to a different combination of PMCs assemblage among plant genotypes. Hence, the first objective of our work was to assess the impacts of grapevine cultivars (varieties of Vitis vinifera L) and grapevine species (entirely different Vitis species) on microbiome assemblage in the phyllosphere at a particular geographic location (to minimize the environmental effects). Later on, impacts of some commercially important grapevine cultivars and terroirs (represented by three French climate zones) were also assessed and compared. Impacts of the season and exterior plant organs (leaf and berries) on microbial taxa structuring in the phyllosphere was also assessed and presented in this work. Furthermore, species-specific impacts on phyllosphere microbiome were also tested and represented.Overall our study assessed and compared the many facets of the factors that may influence themicrobiome structure in the phyllosphere with a special focus on relative selection pressure exerted by grapevine genotype and its interaction with different climatic conditions (or terroir), which may improve our chances to find genes that controls PMCs on phyllosphere, and simultaneously increase our confidence that those genes are actually important in realistic environments and probably those genes would give us new insights for breeding new and healthy grape varieties displaying better traits on their phyllosphere. Moreover, considering that the plant PMCs plays a crucial role in plant health and fitness as it can modulate leaf susceptibility to infection, this study could also be helpful to develop innovative and natural biocontrol methods or phytostimulation against grapevine pathogens or rethink breeding schemes for the creation of innovative resistant varieties.
6

As ilhas de calor urbanas em Jundiaí-SP /

Dorigon, Larissa Piffer. January 2019 (has links)
Orientador: Margarete Cristiane de Costa Trindade Amorim / Resumo: Nesta pesquisa levantou-se a hipótese de que conhecer o campo térmico de Jundiaí e saber a forma e intensidade das ilhas de calor urbanas resulta em informações relevantes a serem inseridas nas ações de planejamento. Acredita-se ainda, que a utilização da metodologia das Zonas Climáticas Locais (LCZs) facilita a comparação dos resultados obtidos em Jundiaí com outras áreas urbanas, uma vez que esta proporciona a uniformização e padronização de terminologias referentes aos usos e ocupações da terra. Para tanto, o objetivo principal foi diagnosticar o campo térmico da cidade de Jundiaí/SP e elaborar uma análise síntese, apresentando as intensidades de ilhas de calor em relação às características de superfície. Para atingir os objetivos propostos as pesquisas de campo ocorreram através da instalação de 10 sensores fixos que registraram dados horários de temperatura entre abril e dezembro de 2017 e realizados 10 episódios de levantamento com medidas itinerantes em agosto e setembro do mesmo ano. Os dados fixos identificaram que a maior expressão das ilhas de calor esteve conectada com uma sequência de estabilidade atmosférica. As maiores intensidades das ilhas de calor foram registradas, predominantemente, nos meses com as menores precipitações totais (junho, julho, agosto e setembro), enquanto no ciclo diário, as maiores intensidades foram noturnas. Notou-se também que, predominantemente, as maiores intensidades estiveram relacionadas com LCZs características de áreas urbana, LC... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: In this research it was hypothesized that knowing the thermal field of Jundiaí and knowing the distribution and intensity of urban heat islands results in relevant information to be included in the planning actions. It is also believed that the use of the Local Climate Zones (LCZs) methodology facilitates the comparison of the results obtained in Jundiaí with other urban areas, since it provides the standardization and standardization of land use and occupation terminology. Therefore, the main objective was to diagnose the thermal field of the city of Jundiaí/SP and to elaborate a synthesis analysis, presenting the urban heat island intensities in relation to the surface characteristics. In order to achieve the proposed objectives, the field research was carried out by installing 10 fixed sensors that recorded hourly temperature data between April and December 2017 and carried out 10 episodes of itinerant survey in August and September of the same year. Data from fixed sensors identified that the highest expression of heat islands was connected with an atmospheric stability sequence. The highest intensities of the urban heat islands were predominantly recorded in the months with the lowest total of rainfall (June, July, August and September), while in the daily cycle the highest intensities were nocturnal. It was also noted that, predominantly, the highest intensities were related to LCZs characteristic of urban areas, LCZ 3, LCZ 3B, LCZ 34 and LCZ 7, all compact and with lit... (Complete abstract click electronic access below) / Doutor
7

Classifica??o do clima local de s?tios urbanos de Feira de Santana

Sim?es, Natanael Augusto Viana 05 April 2017 (has links)
Submitted by Ricardo Cedraz Duque Moliterno (ricardo.moliterno@uefs.br) on 2017-08-08T22:07:22Z No. of bitstreams: 1 dissertacao-versao-final.pdf: 2533927 bytes, checksum: e67082a909ebc3ec8a6260095b8ba929 (MD5) / Made available in DSpace on 2017-08-08T22:07:22Z (GMT). No. of bitstreams: 1 dissertacao-versao-final.pdf: 2533927 bytes, checksum: e67082a909ebc3ec8a6260095b8ba929 (MD5) Previous issue date: 2017-04-05 / The sustainability and the renewable energies are strongly discussed and their relevance in the global community should not be discarded, after all, natural resources are limited. The problems related to the misuse and exhaustion of these resources, besides the emission of gases, occurs mainly within the cities where the majority of the human activities are developed. For this reason, among others, the interest in monitoring climatic factors within cities is growing around the world. Our objective is to identify and classify Local Climate Zones in urban areas of Feira de Santana and propose a local scale sensing infrastructure. In order to achieve the proposed target, it was necessary to explore meteorological observation methods at urban sites; establish a raw data access service and an interface for end users; and to develop a meteorological station capable of measuring the investigated parameters representatively in the urban context. Of the existing methods for classification of urban sites, we used Local Climates Zones proposed by Stewart and Oke in a universe of thirty-five sites spread throughout the city of Feira de Santana. The procedure was carried out in three stages, where temperature and humidity data were first collected using the Arduino platform; in addition to observing and evaluating afforestation, buildings (types, height, spacing and material), types of surface, width of streets, traffic of vehicles and human activity. We adopted as parameter a radius of 500m for thermal source area. As result, we obtained the sites classification, constructed two tables and a map to expose the collected data and observations made identifying each site and its class. In order to fulfill the goal of developing a station adapted to the urban environment, we propose in this work the logical organization of a framework that defines the collection of data by automatic low-cost stations connected to the internet, and the visualization of this data by means of the 52? North SOS. For the construction of the prototype stations, we take into account the sensing of temperature and humidity only for demonstration of the framework, being possible to include more types of sensors in the future. The procedure adopted for the construction took into account the exposure criteria of the WMO temperature and humidity sensors, ensuring that the measured data are relevant to the urban climate. At the end of the application of this methodology, we reached a prototype that implements the proposed framework also using the Arduino platform. All generated source code was made available in a public repository under free software license. Analyzing the descriptions of the sites studied in this work, we noticed some characteristics that make up the city of Feira de Santana in general. As for the proportion of selected Local Climate Zones, the class that best represents Feira de Santana is the Compact low-rise (LCZ 3) evaluated in 40% of the studied sites. In addition, the spatial arrangement of the zones with this classification is very homogeneous in the sense of proximity and adjacencies. We have identified serious sanitation problems that are clearly observed in the absence of sewage and water drainage. The stations were originally developed by us following the guidelines of WMO and Oke, and we achieved a low cost construction using open hardware. / A sustentabilidade e as energias renov?veis s?o assuntos fortemente discutidos e sua relev?ncia na comunidade global n?o deve ser descartada, afinal os recursos naturais s?o limitados. Os problemas relacionados ao mau uso e esgotamento desses recursos, al?m da emiss?o de gases, ocorre principalmente dentro das cidades onde se desenvolvem a maioria das atividades humanas. Por esse motivo, entre outros, o interesse em monitorar fatores clim?ticos dentro das cidades est? crescendo em todo o mundo. Nosso objetivo ? identificar e classificar Zonas de Clima Local em s?tios urbanos de Feira de Santana e propor uma infraestrutura de sensoriamento em escala local. Para alcan?ar a meta proposta, foi necess?rio explorar m?todos de observa??o meteorol?gica em s?tios urbanos; estabelecer um servi?o de acesso aos dados brutos e uma interface para usu?rios finais; e desenvolver uma esta??o meteorol?gica capaz de mensurar os par?metros investigados de forma representativa no contexto urbano. Dos m?todos existentes para classifica??o de s?tios urbanos, utilizamos Zonas de Climas Locais proposto por Stewart e Oke em um universo de trinta e cinco s?tios espalhados pela cidade de Feira de Santana. O procedimento foi realizado em tr?s etapas onde primeiramente foram coletados dados de temperatura e umidade utilizando a plataforma Arduino; al?m de observar e avaliar arboriza??o, constru??es (tipos, altura, espa?amento e material), tipos de superf?cie, largura das ruas, tr?fego de ve?culos e atividade humana. Adotamos como par?metro um raio de 500m para ?rea de fonte t?rmica. Como resultado, obtivemos a classifica??o dos s?tios e constru?mos duas tabelas e um mapa para expor os dados coletados e observa??es realizadas identificando cada s?tio e sua referida classe. A fim de cumprir a meta de desenvolver uma esta??o adaptada para o ambiente urbano, propomos neste trabalho a organiza??o l?gica de um framework que define a coleta dos dados por esta??es autom?ticas de baixo custo conectadas ? internet, e a visualiza??o desses dados geoespacializados atrav?s do 52? North SOS. Para a constru??o do prot?tipo das esta??es levamos em considera??o a coleta de temperatura e umidade apenas para efeito de demonstra??o do framework, sendo poss?vel a inclus?o de mais tipos de sensores no futuro. O procedimento adotado para a constru??o das esta??es levou em considera??o os crit?rios de exposi??o dos sensores de temperatura e umidade da WMO garantindo que os dados medidos s?o relevantes para o clima urbano. Ao final da aplica??o desta metodologia, alcan?amos um prot?tipo que implementa o framework proposto tamb?m utilizando a plataforma Arduino. Todo c?digo-fonte gerado foi disponibilizado em reposit?rio p?blico sob licen?a de software livre. Analisando as descri??es dos s?tios estudados neste trabalho, percebemos algumas caracter?sticas que comp?em a cidade de Feira de Santana de forma geral. Quanto ? propor??o entre as Zonas de Clima Local elegidas, a classe que melhor representa Feira de Santana ? a compacta de baixa eleva??o (LCZ 3) avaliada em 40% dos locais estudados. Al?m disso a disposi??o espacial das zonas com esta classifica??o ? bem homog?nea no sentido de proximidade e adjac?ncias. Identificamos s?rios problemas de saneamento b?sico que s?o claramente observados na falta de esgotos e escoamento de ?gua. As esta??es de coleta foram originalmente desenvolvidas por n?s seguindo as diretrizes da WMO e Oke, e alcan?amos uma constru??o de baixo custo utilizando hardware aberto.
8

Assessment of Energy Recovery Technology in China : Mechanical ventilation system with energy recovery

Piippo, Kaj January 2008 (has links)
<p><!-- --></p><p>In the wake of the economic growth of the Chinese market the past couple of decades, the energy consumption has surged. One of the biggest consequences of the increased energy consumption is a massive increase in CO<sub>2</sub> emission. In fact, China has overtaken the U.S. as the biggest emitter of CO<sub>2</sub>. In light of this energy-saving technology gets more important to implement. District heating is one of the solutions used with success in parts of China where heating is required. In this paper, an energy recovery technology has been examined for two climate zones in China namely a mechanical ventilation system using a flat-plate counter-flow heat exchanger. Beijing is located in a cold zone while Hong Kong is located in a zone with hot summers and mild winters. Cooling load calculations were conducted manually using the RTS - method developed by ASHRAE and heating load calculations were conducted for Beijing using Swedish guidelines stated in BBR. Further, the energy recovery unit (VM1) that was provided by Systemair AB was tested using a rig where different outdoor conditions were simulated. This data was then used to evaluate the potential for energy recovery in a model apartment located in the two zones. As expected, significant differences were obtained when comparing the performance for the two locations.</p><p> </p> / Redan avklarad
9

Assessment of Energy Recovery Technology in China : Mechanical ventilation system with energy recovery

Piippo, Kaj January 2008 (has links)
<!-- --> In the wake of the economic growth of the Chinese market the past couple of decades, the energy consumption has surged. One of the biggest consequences of the increased energy consumption is a massive increase in CO2 emission. In fact, China has overtaken the U.S. as the biggest emitter of CO2. In light of this energy-saving technology gets more important to implement. District heating is one of the solutions used with success in parts of China where heating is required. In this paper, an energy recovery technology has been examined for two climate zones in China namely a mechanical ventilation system using a flat-plate counter-flow heat exchanger. Beijing is located in a cold zone while Hong Kong is located in a zone with hot summers and mild winters. Cooling load calculations were conducted manually using the RTS - method developed by ASHRAE and heating load calculations were conducted for Beijing using Swedish guidelines stated in BBR. Further, the energy recovery unit (VM1) that was provided by Systemair AB was tested using a rig where different outdoor conditions were simulated. This data was then used to evaluate the potential for energy recovery in a model apartment located in the two zones. As expected, significant differences were obtained when comparing the performance for the two locations. / Redan avklarad
10

Energy savings potential of building envelope refurbishment in Swedish single-family houses

Kousah, Rami January 2023 (has links)
Sweden has ca. 2 million single family houses (SFH) housing 52% of the population and representing 44.6% of the overall heated floor area. SFHs account for 39.5% of the total heating demand in Sweden. Energy consumption in older SFHs is much higher than in new ones. SFHs built in the 1960s consume ca. 170% of the annual heating energy demand of SFH built in the 2010s. This study aims to explore the energy savings potential in existing SFHs built between 1960 and 1975 in Sweden through refurbishment of elements of the building envelope and analyze their energy and costefficiency of these measures. Furthermore, it aims to study the effects of variations in climate in Sweden on the energy and cost efficiency of these measures. A hypothetical un-refurbished SFH was modeled and defined using energy simulation tool IDA-ICE based on statistical data and relevant literature reviews. Variations in climate between regions of Sweden were analyzed and 4 suitable locations were suggested to place the hypothetical model in. Suitable building envelope refurbishmentmeasures were selected for the elements of the building envelope. These measures were (a) adding extra insulation to the outer side of external wall (b) replacing and insulating the slab on ground (c) insulating the cold attic on top the existing horizontal slab, and (d) replacing the exiting external doors and windows. Suggested U-values for renovated SFHs from Boverket were used as a goal for the suggested refurbishment measures to reach. Energy performance simulations were performed to estimate savings potential in energy used for heating purposes for the un-refurbished building and each of the suggested measures. Life cycle cost (LCC) study using UPV* method was performed over a lifespan of 30 years. The results of the energy performance simulation showed energy savings potential in all the suggested measures, ranging from ca. 6% to ca. 20% with the measure of replacing the external doors and windows had the most savings potential. The study highlighted rate of improvement in U-values, surface area within which heat losses are occurring, status of thermal bridges, and differences in temperature between air and soil as factors effecting the energy savings potential. The results showed no significant effects of changing locations on the savings potential. LCC analysis showed that the measure of adding extra insulation in the cold attic is the most cost-efficient. It also showed that higher heating demands in colder climate led to more significant role for the energy savings potential in determining the cost efficiency, while the initial costs played a bigger role in warmer climate. The study also showed that choosing materials and products with longer lifespan in addition to having a good energy savings potential may lead to a change in results on the cost-efficiency analysis. The study concludes with highlighting the energy savings potential in building envelope refurbishment and the importance of including both and energy and cost efficiency perspectives when choosing refurbishment measures for existing SFH.

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