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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

Creating new energy orders : Restrictions and opportunities for energy efficient behaviour

Karresand, Helena January 2013 (has links)
Technological development and regulations are gradually making buildings and appliances more energy efficient but household electricity use remains at relatively high levels and does not seem to be decreasing despite improvements in equipment. The point of departure in this paper is the potential for more energy efficient behaviour where household activities are concerned and how that can be studied. It focuses on public housing companies that have built passive houses, in which appliance use is an integral part of maintaining a comfortable indoor climate. The purpose of this paper is to introduce a model called energy orders for analysing household activities in passive houses and identifying restrictions and opportunities for energy efficient behaviour connected to laundry activities. Qualitative interviews have been conducted with public housing residents on their everyday activities and use of appliances. Results show that activities may be realised in very different ways, and they may result in more or less electricity use depending on the resources households use. However, households are affected by various restrictions that prevent them from making better choices energy wise. Also, opportunities for taking certain actions vary between households. While individual choices do matter the households are undoubtedly limited by restrictions shaped by housing companies and other organisations. Identifying the obstacles that deter households from acting more energy efficiently may increase the potential of the passive house to further reduce household electricity use. Housing companies need to provide more flexible solutions in order to create better opportunities for households to act in more energy efficient ways.
2

Inomhusmiljö i miljöcertifierade skolbyggnader : En jämförande studie av upplevd inomhusmiljö i två miljöcertifierade och två konventionella skolbyggnader

Sundström, Viktoria January 2016 (has links)
The purpose of this report was to find out if there were any differences in how the indoor environment was experienced in environmentally certified school buildings compared with similar conventional buildings. For that two certified school buildings, Vegaskolan in Vännäs and Hedlunda preschool in Umeå was compared with two conventional preschools in Umeå, Solbacken and Skattelden, in terms of how the indoor environment was experienced. This was done using a questionnaire and interviews. The results of the survey showed that Vegaskolan had the lowest percentage among the staff that was bothered by various environmental factors, while Hedlunda preschool had the largest share. Hedlunda also had the highest percentage amongst the staff with health problems. All four buildings surveyed, however, had smaller percentages who were disturbed by noise than preschools in general, and the environmentally certified buildings had an even lower percentage. If this is due to the certification is however difficult to say. Since there were more differences between the two certified buildings, it is difficult to draw general conclusions depending on the building type. Most of the differences showed in this study do not depend on the certification of the buildings, but of other causes. However the environmentally certified buildings are more complex than the conventional buildings, with more things that can go wrong. Therefore it requires more monitoring of the indoor environment after the building is put into use, as well as more information to operators and users in order to prevent adverse health effects, which seems to be the case at Hedlunda.
3

Klimatförändringarnas inverkan på inneklimat och energianvändning i passivhus / The impact of climate change on indoor climate and energy use in passive houses

Nylander, Joacim, Sandström, Hugo January 2016 (has links)
Purpose: The purpose of this study is to contribute with knowledge about how the warming effects of climate change may affect indoor living standards, considering that we are already living with some over-temperatures during the summer time. The specific aim is therefore to show how thermal climate in warm passive houses will be perceived, and how specific energy consumption will be affected, within the near future in southern Sweden. Method: To order to achieve the aim, a specific scenario of future temperatures had to be defined. Official climate data for the year 2050 in Gothenburg was collected and compiled. A certified passive house was theoretically exposed to the expected future climate and indoor temperature as well as energy consumption was calculated. Calculations were made using the energy calculation software BV2 for reference conditions and adaptions of both climate as well as technical solutions for greater thermal comfort. Findings: A climate scenario for Gothenburg during year 2050 illustrates that the average year-temperature increases from +7.7°C to +9.9°C. The largest change can be observed during the winter, with an increase peaking at +2.5 ºC. The results show an increase from 65 to 107 number of days during the year in which the studied passive house has an inadequate indoor temperature, as a consequence of over-temperatures. One method for thermal climate enhancing, using a combination of sun screening and air conditioning powered by solar cells, showed having good impact without considerably affecting the specific energy consumption. Implications: In a passive house without air conditioning, the thermal indoor climate will reach an unacceptable level for the tenants, more often in the year 2050, than during the reference period, due to warmer outside temperatures. The method which has the smallest impact upon the energy consumption is sun screening, while air conditioning is the most effective, but also very energy consuming. In order to optimally conserve the thermal indoor climate without decreasing the free energy during the winter, one should install both sun screening and air conditioning in their passive house. Limitations: The result is applicable on passive houses within climate zone III, but the general conclusions made applies for all passive houses in Sweden. Using different methods of calculating the indoor temperature may result in variable results. Keywords: Climate change, Passive house, Indoor climate, Thermal comfort, Energy consumption
4

Passive houses in Uppsala : A study of a new passive solar designed residential area at Ulleråker in Uppsala

Alenius, Jonas, Arons, Erik, Jonsson, Alexander January 2014 (has links)
Uppsala kommun has acquired the land at Ulleråkerand the plan is that it should be the starting point forthe new southeast district. The area is supposed toinclude 8000 new homes. The idea is also that the areashould be a new modern energy-efficient district. Thisreport examines how much energy that could be savedby using a passive house integrated design instead oftodays standard. Simulations in Matlab regarding localenergy utilization has also been done. Calculationsshow that the passive house integrated designgenerates in a total energy saving of 49 per centcompared to the standard house. The local electricalproduction comes from solar cell panels placed on theroofs and facades and the installed power is 19.8 MW.The production covers 80.3 per cent of the totalenergy demand or 91.4 per cent of the electricaldemand per year. But the systems production ismismatched to the local demand for electricity.
5

OPTIMAL OFFICE FOR TENANT: DESIGN PERSPECTIVES

Starikova, Anastasia January 2011 (has links)
At present the office real estate market in Sweden faces new challenges since the economic and real estate crisis of 2008-2010 years. Since the time of economic and real estate crisis of 2008-2010 years, the office real estate market has started to face new challenges. For example, office vacancy rates have increased significantly and challenges how to find the tenant for office premises became very actual. At the same time the demand for high quality office premises still exists on the market but with new requirements to the standards of the office working space. It is happening because the employees’ needs and requirements become more oriented to the comfort and safety of the working place. The employers try to keep and motivate employees by providing the most efficient and comfortable office space to work in and balance on cost-quality issues at the same time. In order to influence on demand from tenants’ and empower tenant search process the landlords have to use new, more competitive methods. The external design of the building and internal design of the office space in particular become more and more significant in leasing, sub-leasing and buying premises property purchase at the real estate office market. It is also useful and important because tenants can change the interior and design project upon their business needs and company’s strategies. The aim of this research paper is to set up the hypothesis that the office’s space design has a significant influence on tenant search process, plays the key role in so-called optimal office for tenant and tests above mentioned hypothesis by the empirical research study (method of questionnaire) among real “market players”-tenant representatives, consulting agencies and property owners. The location for the research and analysis activities is selected as Stockholm and Stockholm’s region, time frame is September - October 2010.
6

Värmebehov i byggnader i en planerad stadsdel med lågtempererad fjärrvärme som värmekälla

Israelsson, Karin January 2023 (has links)
Due to desirable emission reductions and population growth, an increasing energy demand isidentified as a dire issue for energy systems. The introduction of low energy building districtsenables an increased energy system efficiency. This study’s aim is twofold. Firstly, an extensive urban building energy model is used to simulatethe yearly use and geographic distribution of the heat demand for residential and commercialbuildings that are to be supplied by a low-temperature district heating system. Two buildingenergy performance cases are studied; one where all buildings are assumed to be of PassiveHouse standard, and one where the building energy performance is in line with conventionalnew-building regulations in Sweden. The study showed that that Passive Houses will generatethe lowest yearly heat demand and that implementation of ventilation heat recovery has a bigimpact. Furthermore, the results showed that a variation of building energy performance mightbe advantageous when planning a new city district with district heating. Secondly, one specific building is in detail modeled as Passive House and according to BBR-standards and simulated in the building energy simulation software IDA ICE to investigate whatbuilding heating system is best suited for low-temperature heat supply. The temperaturedemands for floor heating and low tempered radiators is investigated and compared toconventional water-based radiators. Results showed that floor heating requires lowertemperature’s than low temperature radiators, but both are well suited for low temperaturedistrict heating. The study’s results will be used as an example for future city district planning aswell as presenting relevant heating systems for low-temperature district heating.
7

Adaptation of buildings for climate change : A literature review

Cheng, Cheng January 2021 (has links)
In September 2020, Northeast China suffered three unprecedented typhoons in half a month, and there was freezing rain in early November, all of which led to the large-scale urban power failure. The occurrence of these phenomena makes people directly see climate change and its impact on the living environment of human beings. Many studies have shown that the cause of climate change is the increase of artificial greenhouse gas emissions since industrialization. In addition to the increase of extreme weather disasters, the most direct manifestations of climate change are the rising temperature, droughts, and rising sea levels. The building sector accounts for 39% of global greenhouse gas emissions and 36% of energy consumption. To ensure the long-term integrity and normal operation of buildings, we need to understand the impact of climate on buildings, and how to deal with it. This paper reviews the literature on climate change and building energy by searching search engines and literature databases. For extreme weather, most literature talks about the impact of power failure, the main strategy is to improve reliability, resilience, sustainability, and robustness, it can help reduce losses and recover as soon as possible. On the other hand, the methods of adaptation to and mitigation of non-disaster weather are reviewed from the perspective of sustainability. This paper mainly reviews the methods of passive technology and strategy for exemplary buildings, building envelope, passive ventilation, lighting/shading, solar energy, bioenergy, dehumidification, passive cooling, and design strategy. According to the local climate, the geographical characteristics of the building, to develop comprehensive passive technology and strategy, can meet or close to meet their energy saving, emission reduction, comfort needs. This paper can provide a technical and strategic reference for the building sector to deal with climate change. / <p></p><p>Via online ZOOM meeting Presentation</p><p></p><p></p><p></p><p></p><p></p><p></p>
8

Lågenergihus : Att bygga energisnålt

Karlsson, Camilla January 2010 (has links)
<p>A large proportion of the energy consumption is in the building industry and a large part goes to heating our homes and premises. In the developing countries' development now threatens the large consumption of energy in our earth's climate. It is in the West world that we must be good role models in terms of energy efficiency. One solution to reduce energy consumption for heating of buildings may be to continue to build low energy houses and passive houses, but it is also about rebuilding the buildings that currently have high energy consumption such as the old Million program Houses. These buildings will be standing many years and their energy consumption will not diminish over time by itself and energy prices will certainly not diminish in the future. This report will touch on the subject mainly new construction, how to build an energy efficient building, but a smaller portion will touch on the subject rebuilding, particularly the solutions that can fit into economic terms.</p><p><strong> </strong></p><p>Calculations have been done to link the concepts of U<sub>mean</sub> of a building and its energy consumption. This was done by calculations using an Excel document created in connection with this thesis.</p><p> </p><p>The buildings and architectural solutions addressed in this report will focus on apartment buildings where the partner of this thesis is Eskilstuna Municipal Building. Eskilstuna Municipality Property manages buildings and premises to Eskilstuna Municipality, but also owns their own house with rental apartments.<strong></strong></p>
9

Lågenergihus : Att bygga energisnålt

Karlsson, Camilla January 2010 (has links)
A large proportion of the energy consumption is in the building industry and a large part goes to heating our homes and premises. In the developing countries' development now threatens the large consumption of energy in our earth's climate. It is in the West world that we must be good role models in terms of energy efficiency. One solution to reduce energy consumption for heating of buildings may be to continue to build low energy houses and passive houses, but it is also about rebuilding the buildings that currently have high energy consumption such as the old Million program Houses. These buildings will be standing many years and their energy consumption will not diminish over time by itself and energy prices will certainly not diminish in the future. This report will touch on the subject mainly new construction, how to build an energy efficient building, but a smaller portion will touch on the subject rebuilding, particularly the solutions that can fit into economic terms.   Calculations have been done to link the concepts of Umean of a building and its energy consumption. This was done by calculations using an Excel document created in connection with this thesis.   The buildings and architectural solutions addressed in this report will focus on apartment buildings where the partner of this thesis is Eskilstuna Municipal Building. Eskilstuna Municipality Property manages buildings and premises to Eskilstuna Municipality, but also owns their own house with rental apartments.
10

Fjärrvärmeanslutna passivhus : Fallstudie av värmelaster och innetemperaturer i fyra flerbostadshus

Nilsson, Daniel January 2012 (has links)
Intresset kring lågenergibyggnader blir allt större och så kallade passivhus, med god isolering, hög lufttäthet och värmeåtervinning, byggs i allt större utsträckning i Sverige och andra europeiska länder. Vissa frågetecken har dock uppkommit kring inomhusklimatet i husen och risken för både under- och övertemperaturer. En annan viktig aspekt är hur husens egenskaper påverkar värmelasterna och hur detta i sin tur påverkar energiförsörjningssystemet. I detta examensarbete undersöks dessa båda aspekter – värmelastegenskaper och innetemperaturer – i fyra likadana nybyggda flerbostadshus i Falkenberg. Mätvärden från husens tekniska system, inklusive lufttemperaturmätningar i samtliga lägenheter, analyseras. Husen består av totalt 108 lägenheter, värms med fjärrvärme och använder ca 50 kWh/m2 Atemp årligen. Värmelastegenskaperna kännetecknas framförallt av låga effektbehov för både uppvärmning och varmvatten samt relativt stora svängningar över dygnet. Husen tycks vara känsligare för variationer i interntillskott än konventionella hus, vilket leder till regelbundna svängningar i effektbehovet för uppvärmning, med en topp under natten och morgonen. Detta leder till förstärkta svängningar i fjärrvärmenätet, vilket skulle kunna undvikas med hjälp av effektstyrning. Passivhusens stora termiska tröghet talar för en sådan möjlighet. Även innetemperaturen uppvisar regelbundna dygnsvariationer, som kan vara något större än i vanliga hus. Låga temperaturer förekommer tidvis under vintern, men resultaten pekar inte på några brister i de tekniska systemen. Temperaturen på sommaren är inte högre än i andra hus, och övertemperaturer tycks inte vara något stort problem i dessa hus. Det kan dock finnas en möjlighet att minska risken för övertemperaturer ytterligare genom användning av nattkyla under varma perioder. Denna möjlighet kan vara ett sätt att utnyttja passivhusens speciella egenskaper för att ytterligare förbättra konceptet. / There is today an increasing interest in low-energy buildings, and the so-called “passive houses” are becoming increasingly popular in Sweden and other European countries. There are however some concerns regarding the indoor climate in these houses, notably the risk of too low indoor temperatures in the winter and too high temperatures in the summer. Another issue is the heat load characteristics of this type of buildings, and how these affect the energy systems. In this thesis, these two aspects – heat load characteristics and indoor temperatures – are analysed in four identical multi-family buildings in Falkenberg, Sweden, using measured values from the buildings’ technical systems and measured indoor air temperatures in all dwellings. The buildings are heated with district heating, comprise 108 dwellings in total and use approximately 50 kWh/m2 annually (space heating, hot water and electricity for building services). The heat loads are mainly characterised by low but varying heat demands for space heating and hot water. The buildings appear to have a higher than usual sensitivity for variations in heat from internal sources and solar gains, leading to regular variations in the heat demand for space heating and fluctuations in the total heat demand. These fluctuations, which may negatively affect the energy system, could be avoided by actively controlling the heat demand for space heating. There are also daily fluctuations in the indoor temperatures, but the buildings perform well in this aspect, with temperatures that stay within the acceptable range most of the time. The summer indoor temperatures do not get higher than in other buildings. A possibility for further improvement within this area could be the use of forced ventilation during the night in hot periods, and hence utilising the buildings’ well insulated and airtight building envelope to keep heat out during the day. This possibility might further improve the passive house concept.

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