Hitzestress beeinflusst nicht nur das Wohlbefinden, sondern vor allem auch die menschliche Gesundheit. Während Hitzestress im Außenraum bereits detailliert untersucht wurde, gibt es nur wenige Studien, welche sich mit thermischen Belastungen im Innenraum befassen. Dabei hält sich die Bevölkerung der Industriestaaten im Durchschnitt durchschnittlich 90 % des Tages im Innenraum auf. Analysen der klimatischen Bedingungen im Innenraum sind essenziell, um zugrundeliegende Prozesse zu verstehen, die Auswirkungen auf den Menschen zu erfassen und passende Anpassungsstrategien entwickeln zu können. Ziel der Arbeit ist es daher, verschiedene Innenraumklimata zu untersuchen und zu bewerten. Zur Untersuchung ihrer Charakteristika wurden Räume ohne Nutzerverhalten innerhalb eines Gebäudes bemessen und analysiert. Die Ergebnisse wurden dann verwendet, um ein detailliertes Innenraummesssystem zu entwickelt und an verschiedenen Standorten in Berlin aufzubauen. Die erhobenen Daten wurden dann verwendet, um die Variabilität von Hitzestress im Innenraum zeitlich und räumlich anhand des UTCI (Universal Thermal Climate Index) zu untersuchen. Den Abschluss bilden umfangreiche Analysen zu den Einflüssen von Innenraum- und Außenraumtemperaturen auf die Mortalität mittels Generalisierter Additiver Modelle (GAM). Die Ergebnisse zeigen, dass Hitzestress im Innenraum eine ernstzunehmende Gefahr darstellt. Alle Untersuchungsräume weisen hohe thermische Belastungen auf. UTCI Werte im Innenraum schwanken innerhalb eines Gebäudes und weisen im Vergleich zum Außenraum sehr hohe Belastungswerte während der Nacht auf. Die höchsten Werte wurden in modernen Gebäuden mit großen Fensterflächen ermittelt. Bezüglich der unterschiedlichen Einflussfaktoren auf das Innenraumklima konnte das Außenklima als wichtigste Einflussgröße bestätigt werden. Des Weiteren zeigt sich, dass die Innenraumtemperatur im Vergleich zur Außenraumtemperatur ein ebenso guter Prädiktor für Mortalität ist. / Heat stress influences not only the comfort of humans but also human health. Heat stress in outdoor environments has been investigated extensively, whereas only a few studies have focused on indoor environments. People in industrialized countries spend approximately 90 % of their day in confined spaces. Analyses of indoor climatic conditions are essential to understanding the underlying processes, determining the impacts on humans and developing appropriate adaptation measures. The aim of this work is to investigate and assess different indoor climates and provide a valuable contribution to future research questions. To analyze indoor climate characteristics or, rather, the influence of different meteorological parameters, the indoor climate in four rooms in one building without user behavior was measured and examined. The results were used to establish a detailed indoor measurement system at different study sites distributed over Berlin. The gathered data were then used to assess indoor heat stress variability on a temporal and spatial scale using the UTCI (Universal Thermal Climate Index). Finally, an extensive analysis of the influence of indoor climate and outdoor climate on mortality was conducted by applying generalized additive models (GAM). The results indicate that indoor heat stress is a severe threat. All study rooms experienced high thermal loads, regardless of the building type they were located in or their location within the building. Indoor UTCI values varied within buildings and further exhibited very high heat stress levels during night compared to outdoors. The highest values were measured in modern buildings with a high percentage of windows. Among the different driving factors of indoor climate, outdoor climate was confirmed to have the highest impact. Moreover, this thesis shows that indoor air temperature is an equally good predictor of mortality compared to outdoor climate.

Low-energy buildings have, in recent years, gained attention and moved towards a large-scale introduction in the residential sector. During this process, national and international criteria for energy use in buildings have become stricter and the European Union has through the Energy Performance of Buildings Directive imposed on member states to adapt their building regulations for ‘Nearly Zero Energy Buildings’, which by 2021 should be standard for new buildings. With a primary focus on new terraced and detached houses, this thesis analyses how the concept of low-energy buildings may be further developed to reduce the energy use in the residential sector. The main attention is on the technical performance in terms of indoor climate and heat consumption as well as on the market diffusion of low-energy buildings into the housing market. A multidisciplinary approach is applied, which here means that the concept of low-energy buildings is investigated from different perspectives as well as on different system levels. The thesis thus encompasses methods from both engineering and social sciences and approaches the studied areas through literature surveys, interviews, assessments and simulations. The thesis reveals how an increased process integration of the building’s energy system can improve the thermal comfort in low-energy buildings. Moreover, it makes use of learning algorithms – in this case artificial neural networks – to study how the heat consumption can be predicted in a low-energy building in the Swedish climate. The thesis further focuses on the low-energy building as an element in our society and it provides a market diffusion analysis to gain understanding of the contextualisation process. In addition, it suggests possible approaches to increase the market share of low-energy buildings. / <p>QC 20140321</p>

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

Smart environments are increasingly common. By utilizing sensor data from the indoor environment and applying methods like machine learning, they can autonomously control and increase productivity, comfort, and well-being of occupants. The aim of this thesis was to model indoor climate in conference rooms and use K-means clustering to determine quality levels. Together, they enable categorization of conference room quality level during meetings. Theoretically, by alerts to the user, this may enhance occupant productivity, comfort, and well-being. Moreover, the objective was to determine which features and which k would produce the highest quality clusters given chosen evaluation measures. To do this, a quasi-experiment was used. CO2, temperature, and humidity sensors were placed in four conference rooms and were sampled continuously. K-means clustering was then used to generate clusters with 10 days of sensor data. To evaluate which feature combination and which k created optimal clusters, we used Silhouette, Davis Bouldin, and the Elbow method. The resulting model, using three clusters to represent quality levels, enabled categorization of the quality of specific meetings. Additionally, all three methods indicated that a feature combination of CO2 and humidity, with k = 2 or k = 3, was suitable.

Energieffektivisering inom bostäder är viktigt för att nå bestämda mål inom den Europeiska unionen, däremot kommer inte en bostadsägare att investera i energieffektiva åtgärder om de inte är lönsamma. Detta arbete kommer att undersöka energibesparingen och lönsamheten av att införa olika förbättringsåtgärder på ett lättbetonghus i Söderhamn vilket är studieobjektet i arbetet. Syftet är att undersöka byggnadens energibalans och hur olika åtgärder påverkar energianvändningen, upplevelsen av inomhusklimatet och driftkostnaden. Studieobjektet genomgick en energikartläggning för att sedan undersöka olika förbättringsåtgärder. Kartläggningen var utförd med simuleringsverktyget IDA Indoor Climate and Energy för att konstruera en referensmodell som inkluderade alla insamlade data från studieobjektet. Tidigare forskningsstudier inom området användes som vägledning till val av förbättringsåtgärder på studieobjektet. Energiförändring utav åtgärderna användes sedan i en kostnadskalkyl som var utförd med annuitetsmetoden för att åstadkomma den årliga kostnadsbesparingen vid installation för var och en av åtgärderna. Koldioxidhalten mättes i början av projektet för att undersöka luftkvalitén i byggnaden och om den behöver åtgärdas. Studieobjektets primärenergital blev 148 kWh/(m2·år) vilket var 43 % högre än Boverkets byggreglers energikrav för småhus. Byggnadens värmebehov var 18 209 kWh/år och kunde minskas med 42,7 % vid installation av ett åtgärdspaket och då var primärenergitalet 109 kWh/(m2·år). De tre mest energieffektiva åtgärder var att tilläggsisolera ytterväggar, isolera taket och minskning av inomhustemperaturen. Den mest kostnadseffektiva av enskilda åtgärder var att isolera taket ifall övervåningsutrymmet utnyttjades och att isolera källaren var den minst lönsamma av besparingsåtgärderna. Ventilationsproblemet i byggnaden kunde åtgärdas med installation av ett FTX-system som använder luftflödet 0,35 l/(s·m2) och 0,1 l/(s·m2) när inga personer är i byggnaden. Att komplettera uppvärmningen med en värmepump var en lönsam investering men ökade primärenergianvändningen och gör byggnadens energisystem mer komplext. Det rekommenderas att isolera klart taket ifall boende har intresse av att utnyttja övervåningsutrymmet. / Energy efficiency in dwellings is crucial in reaching goals set within the European Union, but homeowners won’t invest in energy-efficient measures unless it is cost-effective. This study is going to investigate the energy savings and cost-effectiveness of different renovating measurements for a light-concreate house in Söderhamn. The aim is to investigate the building’s energy balance and how renovating measurements affect the energy use, the indoor climate and the operating cost. An energy audit was performed on the building for the purpose of investigating the various measurements. The audit was achieved with IDA Indoor Climate and Energy simulation tool, which was used to construct a reference model that included data from the studied building. Previous research in the field were used for selecting the renovating measurements used in this study. The results of the simulations were then used to carry out a cost analysis with the equivalent annual cost method to evaluate the annual cost saving for each measurement. The carbon dioxide level was measured in the beginning of the project to investigate the indoor air quality in the building and if it needed to be addressed. The primary energy use of the building was 148 kWh/(m2·year), which was 43 % more than Building regulations energy requirements for single-family households. The heat demand was 18 209 kWh/year and could be reduced by 42,7 % when installing a created renovation package and resulting in the primary energy use of 109 kWh/(m2·year).  The three most energy efficient measures were adding extra insulation on external walls, insulating the roof and decreasing the indoor temperature level. The most cost-effective measure was to insulate the roof if the upstairs area were heated and insulate the basement walls was the least cost-effective of the energy efficient measures. The ventilation problem was fixed with installation of an FTX system that switched to an air flow of 0,35 l/(s·m2) to 0,1 l/(s·m2) during unoccupancy. Complementing the heat demand with a heat pump was a cost-effective measure but did increase the primary energy use. It is recommended to finish isolating the roof if the family is interested in using the unoccupied space.

The building sector alone accounts for almost 40% of the total energy demand and people spend more than 80% of their time indoors. Reducing energy demand in buildings is essential to the achievement of a sustainable built environment. At the same time, it is important to not deteriorate people’s health, well-being and comfort in buildings. Thus, designing healthy and energy-efficient buildings is one of the most challenging tasks. Evaluation of buildings with a broad perspective can give further opportunities for energy savings and improvement of the indoor climate. The aim of this thesis is to understand the functionality, regarding indoor climate and energy performance, of a low-energy building. To achieve this, a multi-dimensional approach is used, which means that the building is investigated from several points of views and with different methods. A systems approach is applied where the definition of the system, its components and the border to its environment, is essential to the understanding of a phenomenon. Measurement of physical variables, simulations, and qualitative interviews are used to characterize the performance of the building. Both energy simulation and computational fluid dynamic simulations are used to analyse the energy performance at the building level as well as the indoor climate at room level. To reveal the environmental impact of the low-energy building studied in this thesis the CO2 emissions and embodied energy have been investigated regarding different surrounding energy systems. The evaluated building is situated at the west coast of Sweden and uses about 50% of energy compared to a comparable ordinary Swedish building. The building is well-insulated and an air-to-air heat exchanger is used to minimise the heat losses through ventilation. The houses are heated mainly by the emissions from the household appliances, occupants, and by solar irradiation. During cold days an integrated electrical heater of 900 W can be used to heat the air that is distributed through the ventilation system. According to measurements and simulations, the ventilation efficiency and thermal environment could be further improved but the occupants are mostly satisfied with the indoor climate. The control of the heating system and the possibility for efficient ventilation during summertime are other important issues. This was found through quantitative measurements, simulations and qualitative interviews. The low-energy building gives rise to lower CO2 emissions than comparable buildings, but another energy carrier, such as district heating or biofuel, could be used to further improve the environmental performance of the building. The total energy demand, including the embodied energy, is lower than for a comparable building. To understand the functionality of a low-energy building both the technical systems and the occupants, who are essential for low-energy buildings, partly as heat sources but mainly as users of the technical systems, should be included in the analysis.

This study examines the use of building modeling and energy simulations in the design process  of  a  building.  The  take-off  point  is  the  notion  of  energy  simulations  being needed early and throughout the building design process, and that the lack of energy simulations may be explained by the fact that they are time consuming and therefore often too expensive. A greater interoperability between software tools used by relevant disciplines,  such  as  the  architect  and  the  energy  specialist,  would  create  smoother workflows, which would reduce this cost and open up for more frequent and iterative energy  simulation  processes.  The  study  is  an  assessment  of  the  modeling  tool  Revit and  the  simulation  tool  Virtual  Environment  and  whether  they  can  create  smoother workflows, and make leeway for a more frequent use of energy simulations throughout the  design  process.  It  also  investigates  the  limitations  of  what  can  be  examined  by simulations in Virtual Environment. This will hopefully help clarify the future role of energy  simulations  in  design  processes.  The  method  is  a  trial  by  error  approach  of testing the two software tools by building and simulating a model. The results of these tests  show  that  the  workflow  is  not  optimal  (and  therefore  time  consuming)  for frequent  and  iterative simulations  throughout the  design  process,  but  it  also  reveals some  great  possibilities  of  what  can  be  performed  with  these  two  powerful  tools  at hand.  Further  development  with  regards  on  platform  independency  of  the  building information  model,  including  seamless  exporting  and  importing,  seems  necessary  to strengthen the future role of energy simulations.

This study has been carried out in the spring of 2014 on behalf of PQR Consult AB in Stockholm. The aim of the study has been to analyse the energy usage of the building Skarpövägen 1 in order to explore the possibilites of saving energy by using appropriate equipment. These possible solutions have been simulated by using the programe IDA Indoor Climate and Energy, combined with a life cycle cost analysis. The laundry building, Skarövägen 23, has also been analysed due to its high amount of energy usage. The result of the energy analysis showed that the energy usage was much higher than the energy declaration. The energy usage of Skarpövägen 1 was 193 kWh/m2, which is 25 % higher than the energy declaration of 155 kWh/m2. Based on the energy saving actions, the most profitable investment would be to install heat recycling that would save 47470 kWh district heating per year with a pay-back time of 14 years. The results for the laundry building showed that there is a possibility to save up to 75% of the electricity usage by replacing certain equipment that is dependent on a high amount of energy. Throughout the whole analysis it has been clear that the energy usage in the buildings are higher than necessary. However, the energy saving actions have shown that there are ways to reduce the usage in the buildings. Some changes are simple to make while others would take longer, with varied pay-back time. In the long run those changes are vital for a sustainable reduction of energy usage. / På uppdrag av PQR Consult AB i Stockholm har detta examensarbete utförts under våren 2014. Syftet var att utföra en energikartläggning av byggnaden Skarpövägen 1 och simulera energibesparande åtgärder i programmet IDA Indoor Climate and Energy. Utöver detta har en livscykelkostnadsanalys gjorts för att underlätta ekonomiska jämförelser. Även tvättstugan, Skarpövägen 23, har delvis kartlagts eftersom den har en hög energianvändning med all elutrustning i byggnaden. Resultatet i energikartläggningen visade att energianvändningen var betydligt högre än energideklarationens värden. För Skarpövägen 1 var energianvändningen 193 kWh/m2 vilket är ca: 25 % högre än energideklarationens 155 kWh/m2. Efter att ha utvärderat de simulerade energibesparingsåtgärderna för Skarpövägen 1 så dras slutsatsen att den mest lönsamma investeringen skulle vara att installera ett värmeåtervinningssystem vilket skulle ge en besparing på 47470 kWh fjärrvärme per år och ha en återbetalningstid på 14 år. Resultatet för tvättstugan visade att 14880 kWh el årligen skulle sparas om torkskåpen byttes ut, vilket är en sänkning med ca: 75 % av elbehovet jämfört med befintliga torkskåp. De energibesparande åtgärderna har visat att utrymme finns för besparingar i byggnaderna vilket är ett viktigt steg på vägen att minska energianvändningen i bostadssektorn.

The use of air-to-air heat pumps in a church has been investigated with respect to preservation aspects and energy efficiency. The paper discusses the general problem and presents the results from a case study. The temperatures, velocities and humidity in the church have been measured for four different heating modes. The study shows that there is a significant potential for energy savings with heat pumps and that temperature distribution and air movements are comparable to conventional heating.

Läckö Castle is an historic building that has never been permanently heated but has been dehumidifiedsince the early 2000s to house museum collections. The purpose of the work was to evaluate thedehumidification performance and compare the climate with the state of preservation of wooden wallpaintings. Compiled climate recordings for different rooms in the castle from 1997 to 2009, before andduring dehumidification, were used and compared to the outside climate. The RH set point value of 70 % for dehumidification was not reached often, especially in winter with high outside RH. Wood painted witha linseed oil paint performed well, whereas paint containing resin was seriously damaged. It is concludedthat microclimatic differences in relation to dominating wind direction are important. The air exchangeof the building is very decisive for dehumidification efficiency.