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  • 1.
    Andersson, Adam
    et al.
    Dalarna University, School of Technology and Business Studies, Construction.
    Berggren, Pontus
    Dalarna University, School of Technology and Business Studies, Construction.
    Utvärdering av träbjälklag i ett äldre flerbostadshus med avseende på stegljud och nedböjning: Mätningar och möjliga åtgärder och åtgärdsförslag2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    New buildings will only maginally contribute to future quantity of residential housing. Therefor new knowledge of past building technics are required, to asses which action propsals are suitable when interventions are considered. Objective. This study aims to evaluate lightweight timber joist floors in a multi-story residential building from 1903, with regard to footfall noise and deflection. Method. Data has been collected with a survey and through measurements of footfall noise and deflection. The purpose of the survey is to evaluate the residentals subjective perception of footfall noise and deflection. Footfall noise has been measured with a tapping machine in accordance with Swedish Standards. The deflection has been measured with Leica NA2 paired with a parallel-plate micrometer, GFS1, for precise leveling assessment. Results. The survey shows that the residents don’t experience any issues with regard to footfall noise and deflection. The measurements show a L’nT,w+CI,50-2500 level of 55 dB and an average deflection of 0.320 mm/kN. Conclusion. Footfall noise- and deflection levels satisfy today’s requirements according to Swedish Standards and therefor the results doesn’t motivate any action proposals or interventions.

  • 2.
    Bergkvist, Johanna
    et al.
    Dalarna University, School of Technology and Business Studies, Construction.
    Strandberg, Linda
    Dalarna University, School of Technology and Business Studies, Construction.
    En pedagogisk byggnad för hållbar utveckling: Utformning av en programhandling för ett kretsloppshus med fokus på social och ekologisk hållbarhet2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The purpose of this thesis is to establish a functional program for an eco-cycle building where people can be

    reached with knowledge of sustainable development. The background to this is that the municipality of

    Borlänge approved a plan program with the vision of creating a new, climate neutral district and thereby

    become a precursor for sustainable construction in the region. For instance, the functional program is meant

    to investigate the background and the prerequisites that existed. In the municipality’s plan program, the

    building is described to have an educational function for the district and for Borlänge; a place which focuses

    on practical demonstrations and education for students and residents in recycling issues for energy, water

    and waste/material in a comprehensible and compelling way. The eco-cycle building is planned to be

    established near the new school, with classes from 6 to 9, to make a cooperation possible.

    Requests from the municipality is that the eco-cycle building can work like a hub in the new district, but

    also become a new place of interest and put Borlänge on the map for sustainable construction. Sustainable

    construction includes resource management, minimized energy use and renewable energy sources, but also

    that resources like energy, waste and water circulate in an eco-cycle. Theory has been obtained from

    literature focusing on how we should build our houses and cities if we want to join and create a sustainable

    society.

    Part of the purpose of this thesis was to explore how to disseminate information on environmental and

    circular issues in an educational way. The theoretical part of the thesis is therefore focusing on selected parts

    of education obtained from previous research in children and youth learning for sustainable development,

    since studies show that it is important that children learn about these issues early in life. Education for

    Sustainable Development is an important prerequisite for achieving the sustainability goals set by the UN

    until 2030. Upcoming generations must learn a sustainable way of life right from the start while the existing

    population must drastically change their lifestyle.

    In order to gather empiricism, interviews were held with people who have been involved in the planning

    work with the new district. It turned out that there were former driving spirits who introduced the idea of the

    eco-cycle building, but that it doesn’t currently are the major priority in the ongoing work with the new

    school and housing.

    Engaging the users at an early stage provides better conditions for achieving a result that is effective and

    satisfying for all parties. The theory of design dialogues has therefore been studied to demonstrate the

    importance of a good dialogue to quickly identify needs and develop ideas in design work.

    The result of the thesis, the functional program, can be seen as a draft on conceptual level with features and

    expressions that can be applied to a building of this kind, and an inspiration for continued work. In the

    functional program, our interpretations form how the eco-cycle building would meet the requests and

    functions that’s been requested in the plan program, in order to benefit as much as possible in the

    municipality's future work with the building.

    Conclusions are that there are no precursors of the eco-cycle building as a concept. Despite a large number

    of sources of inspiration from various aspects, no example was found that combines all the aspects we have

    the ambition to develop for this building. The eco-cycle building as a concept could play an important role

    for how to handle sustainable issues in a district or in a whole city. However, further work is required to

    investigate how the building should be run and managed, as well as more extensive studies of which

    technical solutions to apply. Further work is also required to optimize the building for the future location,

    and the size of the building that are appropriate. There is a great interest in the building from various

    participants in Borlänge, but to implement the idea of the eco-cycle building, one or more people need to

    embrace the project with the commitment that previously existed in the organization.

  • 3. Birchall, Sarah
    et al.
    Gustafsson, Marcus
    Dalarna University, School of Technology and Business Studies, Energy Technology. KTH.
    Wallis, Ian
    Dipasquale, Chiara
    Bellini, Alessandro
    Fedrizzi, Roberto
    Survery and simulation of energy use in the European building stock2016Conference paper (Refereed)
    Abstract [en]

    the work towards increased energy efficiency. In order to plan and perform effective energy renovation of the buildings, it is necessary to have adequate information on the current status of the buildings in terms of architectural features and energy needs. Unfortunately, the official statistics do not include all of the needed information for the whole building stock.

     

    This paper aims to fill the gaps in the statistics by gathering data from studies, projects and national energy agencies, and by calibrating TRNSYS models against the existing data to complete missing energy demand data, for countries with similar climate, through simulation. The survey was limited to residential and office buildings in the EU member states (before July 2013). This work was carried out as part of the EU FP7 project iNSPiRe.

     

    The building stock survey revealed over 70% of the residential and office floor area is concentrated in the six most populated countries. The total energy consumption in the residential sector is 14 times that of the office sector. In the residential sector, single family houses represent 60% of the heated floor area, albeit with different share in the different countries, indicating that retrofit solutions cannot be focused only on multi-family houses.

     

    The simulation results indicate that residential buildings in central and southern European countries are not always heated to 20 °C, but are kept at a lower temperature during at least part of the day. Improving the energy performance of these houses through renovation could allow the occupants to increase the room temperature and improve their thermal comfort, even though the potential for energy savings would then be reduced.

  • 4.
    Blomqvist, Stina
    et al.
    Dalarna University, School of Technology and Business Studies, Construction.
    Helgesson, Robin
    Dalarna University, School of Technology and Business Studies, Construction.
    Framtagning av yttervägg för småhus: En analys med hänsyn till kommande energikrav2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Today is the specific requirements for the building’s energy use in new buildnings. These requirements come under the EU directive to be tightened firmly to the year 2020. This work was the basis of an interpretation of the coming energy requirements, 2020 requirements, designing a new energy-efficient exterior wall construction. This has been done with Fiskarhedenvillan and the construction has been valued in terms of material cost, assembly and the square meter price.

    By calculations and fact finding, demonstrated how energy in small houses could be reduced by replacing the insulating material to a material with lower heat conductivity. The method was to interpret the coming energy requirements and analyze Fiskarhedenvillan current wall construction. Next, search for information and facts about various insulation materials and then design a new proposal on the exterior wall construction.

    The outer wall construction is a crucial factor for the building envelope energy efficiency. Because Fiskarhedenvillan chosen to focus only on the outer wall, this work is delimited to that part of the building envelope.

    An important conclusion of this work is that the 2020 objectives can be met by improving the exterior wall construction and that it is possible to make a design that meets the requirements in entire Sweden

  • 5.
    Brinkebäck, Eric
    et al.
    Dalarna University, School of Technology and Business Studies, Construction.
    Jönsson, Johan
    Dalarna University, School of Technology and Business Studies, Construction.
    Fallstudie av moderna timmerhus: Kvalitetskontroll av nybyggda timmerhus mot FST:s kvalitetsnormer och BBR:s kommande energihushållningskrav2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    A study has been conducted to investigate how log houses will meet the new requirements regarding U-value and specific energy use with primary energy factor as a basis, which will be put into use in 2017. In the study, two houses have been investigated. Both houses were constructed with 200 mm thick logs without any additional isolation. Both houses have geothermal heating systems. The study found that the new requirements will be rough against timber house constructions with geothermal or electricity as a heating system, since a primary energy figure of 1.6 will be multiplied by the total energy consumption when heated by electricity.

  • 6. Chai, Jiale
    et al.
    Huang, Pei
    City University of Hong Kong.
    Sun, Yongjun
    Climate change impact on energy balance of net-zero energy buildings in typical climate regions of China2019In: E3S Web of Conferences, E-ISSN 2267-1242, Vol. 111, article id 04004Article in journal (Refereed)
  • 7. Chai, Jiale
    et al.
    Huang, Pei
    City University of Hong Kong.
    Sun, Yongjun
    Investigations of climate change impacts on net-zero energy building lifecycle performance in typical Chinese climate regions2019In: Energy, ISSN 0360-5442, E-ISSN 1873-6785, Vol. 185, p. 176-189Article in journal (Refereed)
    Abstract [en]

    Net-zero energy building (NZEB) is widely considered as a promising solution to the current energy problem. The existing NZEBs are designed using the historical weather data (e.g. typical meteorological year-TMY). Nevertheless, due to climate change, the actual weather data during a NZEB’s lifecycle may differ considerably from the historical weather data. Consequently, the designed NZEBs using the historical weather data may not achieve the desired performances in their lifecycles. Therefore, this study investigates the climate change impacts on NZEB lifecycle performance (i.e., energy balance, thermal comfort and grid interaction) in different climate regions, and also evaluates different measures' effectiveness in mitigating the associated impacts of climate change. In the study, the multi-year future weather data in different Chinese climate regions are firstly generated using the morphing method. Then, using the generated future weather data, the lifecycle performances of the NZEBs, designed using the TMY data, are assessed. Next, to mitigate the climate change impacts, different measures are adopted and their effectiveness is evaluated. The study results can improve understanding of the climate change impacts on NZEB lifecycle performance in different climate regions. They can also help select proper measures to mitigate the climate change impacts in the associated climate regions.

  • 8. Chai, Jiale
    et al.
    Huang, Pei
    City University of Hong Kong.
    Sun, Yongjun
    Life-cycle analysis of nearly zero energy buildings under uncertainty and degradation impacts for performance improvements2019In: Energy Procedia, ISSN 1876-6102, E-ISSN 1876-6102, Vol. 158, p. 2762-2767Article in journal (Refereed)
    Abstract [en]

    Sizing the nZEB systems properly is crucial for nZEBs to achieve the desired performances. The energy demand prediction uncertainties and the components’ degradation are two major factors affecting the nZEB systems sizing. The energy demand prediction has been studied by many researchers, but the impacts of degradation are still neglected in most studies. Neglecting degradation may lead to a system design that can perform as expected only in the beginning several years. This paper, therefore, proposes an uncertainty-based life-cycle performance analysis (LCPA) method to study the impacts of degradation on the nZEBs longitudinal performance. Based on the LCPA method, this study also proposes a two-stage method to enhance the nZEB system sizing. The study can enhance the designers’ understanding of the components’ degradation impacts. Case studies show that an nZEB might not achieve zero energy targets after years due to degradation. The proposed two-stage design method can effectively mitigate this problem.

  • 9.
    Dellfjord, Veronica
    Dalarna University, School of Technology and Business Studies, Construction.
    Kunskap hos privatpersoner om fukt på kallvind2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    It is common that homeowners are recommended to add an insulation layer on the attic to lower building heating energy, however many do not realize the problem with complementary insulation compared to what the building and the building shell is adapted for. The lack of knowledge of the homeowners, can result in that they accidentally fill the longitudinal ventilation slits on the cold roof that is there to maintain the natural ventilation and prevent air from drying out any moisture.

    The aim is to find thus out:

    • How much knowledge do the homeowners have about the risk of moisture problems in the cold roof, and how to prevent future moisture damage in the best way, depending on the design of the roof?

    • Is there a risk of moisture problems for the objects studied, based on moisture measurements and high moisture content?

    The method chosen for the study was semi-structured interviews, containing sixteen questions, with homeowners and measurements of relative humidity of air and wood and the moisture content in the wood. The study was limited to the spring of 2016 and to four homeowners.

    It turned out to differ little among the interviewers on how much knowledge they had about moisture in cold roofs and how much knowledge they possess today. Some had enough knowledge to prevent moisture damage while others needed more information. Several felt that the insurance company is where they have to acquire information from, preferably in the form of a leaflet with short questions, sent out annually.

    The measurements proved to give good results with little risk of moisture damage to the cold roofs. There were no high moisture content in neither truss nor inside roof.

  • 10. Eriksson, Anna-Maria
    Energieffektivisering av klimatskal med hänsyn till kulturhistorisk värdering: Fallstudier av tre befintliga småhus från 1900-talet ur bevarandesynpunkt2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Increasingly stringent legal requirements make it difficult to energy efficiency in existing buildings without changing their appearance.

    The purpose of the study is to investigate how much energy, for three existing single-family homes built in the 1900s, which is achievable by improving the building envelope, ie, ceilings, walls, floors, windows and doors, without distorting the building's appearance and while maintaining their cultural values.

    The work consisted of a pilot study where three buildings were identified, a research stage where information about the buildings were developed and an inference stage where energy saving measures proposed were developed and evaluated. Buildings that were good representatives of their time and style sought. Buildings from the 1910s, 1930s and 1970s, was located. Since it was done case studies, interviews and surveys. To investigate the building envelope was conducted U-value calculations and energy calculations of the existing building commitment and buildings based on the proposed policy proposals.

    None of the buildings reached after the proposed action down to the passive house requirement 59 kWh/year/m2 Atemp or BBR requirement 110 kWh/year/m2 Atemp for a building-specific energy consumption. The maximum possible energy efficiency for the three buildings erected during the 1900s, which is achievable without corrupting the buildings' appearance while preserving their cultural values is 13.0 kWh/year/m2 Atemp, 49.7 kWh/year/m2 Atemp respectively 64.8 kWh/year/m2 Atemp.

    Conclusions of the work is that buildings from the 1910's can be addressed by isolating the windows, put one extra door on the inside of the front door and additional insulation in sloping roof. Buildings from the 1930s can be addressed by isolating windows with insulating glass on the inside of the windows and doors with an extra door on the inside of the front door. Buildings from the 1970s can fix the windows by changing them into energy windows, no action on the floor but the facade insulated externally with vacuum insulation. The building from the 1970s fared best in the comparison because it was the authentic condition from the beginning, which meant that the improvement was greater than for example the building from the 1910s that was already rebuilt before action was proposed.

  • 11.
    Fiedler, Frank
    et al.
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Bales, Chris
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Persson, Jannika
    Dalarna University, School of Technology and Business Studies, Construction.
    Gustavsson, Marcus
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Kovacs, Peter
    RISE.
    Hemlin, Olleper
    RISE.
    Ollas, Patrik
    RISE.
    Thuvander, Liane
    Chalmers Tekniska Högskolan.
    Femenías, Paula
    Chalmers Tekniska Högskolan.
    Lundin, Michelle
    Chalmers Tekniska Högskolan.
    Larsson, David
    Solkompaniet.
    Miljontak Delprojekt 2: Sammanfattning av litteratursammanställning2018Report (Other academic)
  • 12.
    Goldheim Jämthagen, Fredrik
    et al.
    Dalarna University, School of Technology and Business Studies, Construction.
    Reyier, Marcus
    Dalarna University, School of Technology and Business Studies, Construction.
    Behovsstyrning av ett småhus: Behovsstyrning av värme, ventilation, belysning och dess påverkan på energianvändningen i ett småhus2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    All people use some kind of energy to live. A disadvantage of this is that it has a

    impact on the climate, because energy consumption is greater than the Earth is

    capable of. Sweden has set a goal that energy use should be 20% more

    effective by year 2020. Boverket’s building rules have several instruments where

    energy use is greatly affected. Among other things, the energy performance is

    measured in primary energy. BBR provides guidelines for air turnover and flows.

    These affect the use of heating energy in a building. The rules makes a

    possibility of reducing flow and turnover when no need exists. In order to effect

    the use of energy in a building, demand control of energy systems can be used.

    The indoor climate can then be affected depending on whether people are in the

    room or not. The purpose of the study is to investigate differences in purchased

    energy between demand controlled and no demand controlled indoor climate. In

    order to assume a single-family house, the study was based on Dalarnas villa. It

    is a modern two-story house with large windows. The house is built between

    Borlänge and Falun. Demand control of a single house is a relatively unexplored

    area. RISE performs a study at the time of writing. They investigate the

    possibility of demand control ventilation in homes. In order to enable efficient

    demand control, several sensors and set points are required, as well as a

    control system that enables communication between the sensors. The test

    object was used to calculate energy use with different grade of demand control.

    The calculations were performed in three different ways to verify the result.

    These three were: hand calculation, TMF energi 7.11 and IDA ICE. The different

    ways consider different parameters and data. With IDA ICE, a theoretical model

    was built and several simulations were performed. The results of the calculations

    differ relatively slight between the different calculations. What all the calculations

    indicate is that there is a possibility for reducing energy use with demand

    control. When lighting, heating and ventilation are controlled, a reduction of 26 %

    (exclude hot water and equipment electricity) in energy consumption can be

    achieved by using demand control. This is due to the fact that heat loss is

    effectively reduced with less airflow and lower indoor temperature when no

    person is present in the room. The possibility of demand control in this small

    house is seen to be good, but in order to have an efficient demand control, a

    well-adjusted control system is required.

  • 13.
    Gustafsson, Elina
    et al.
    Dalarna University, School of Technology and Business Studies, Construction.
    Persson, Jannika
    Dalarna University, School of Technology and Business Studies, Construction.
    Miljövänliga material i villakonstruktion: En jämförande studie av fyra olika vägg- och vindsbjälklagsförslag gällande miljö och hälsa, med fuktanalys och U-värdesberäkningar.2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Environmental awareness today is larger than ever, and continues to expand. The increasing knowledge has led to a rising demand of using environmental friendly materials and the interest of building and living in a way that is good for the health and environment has grown with it. The small house manufacturer Fiskarhedenvillan, has noticed this demand and that is why this study has been done.

    The purpose of this study is to investigate what opportunities there is to replace one or some of the chosen materials from Fiskarhedenvillans construction to materials that fulfills higher demands at being environment- and healthfriendly. The U-value of the suggestions should be equivalent or improved. The most important aspect otherwise was to investigate how well the new suggestions manage moisture impact. The suggested materials have been windbarrier board, insulation, waterproofing, vapour barrier, tape and interior lining.

    The study was performed by a thorough investigation of the materials that could be of interest. This was done by searching for relevant information through databases, reports, manufacturers homepages and from other construction related books and internet sources. The moisture simulations and U-value calculations were done in the simulation program WUFI pro 5.3. A survey was sent out to Fiskarhedenvillans agents to investigate the housing markets interest in changing to environmental-friendly materials.

    The investigations resulted in four functional suggestions on external wall construction with loft floor, which was chosen based on the purposes. The results show that all constructions successfully handled the moisture exposure, except the wallconstruction with cellulose based insulationboards, where the relative humidity during the whole year stays at such high levels that risk of mould- and moisturedamage is existing. The result of the U-value calculations shows that the suggestions have similar U-value to Fiskarhedenvillans current constructions. However, the proposal with hempinsulation had to be extended 10cm in order to meet this requirement. For the loft floor with hempinsulation it was accepted that the U-value was somewhat lesser than the others. The result from the survey shows that more than half of the agents have experienced a demand from potential customers to change materials to more environment-friendly.

    The most important conclusion is that it is possible to change materials in a house and maintain its construction capacity while managing the impact of moisture as well. Since customers appear willing to pay more for changing materials, we believe that it would not be a problem for Fiskarhedenvillan to establish at least one construction possibility with environmental-friendly materials.

  • 14.
    Gustafsson, Marcus
    Dalarna University, School of Technology and Business Studies, Energy Technology. KTH, Strömnings- och klimatteknik.
    Energy Efficient Renovation Strategies for Swedish and Other European Residential and Office Buildings2017Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The high energy use in the European building stock is attributable to the large share of old buildings with poor energy performance. Energy renovation of buildings is therefore vital in the work towards energy efficiency and reduced environmental impact in the EU. Yet, the strategies and energy system implications of this work have not been made clear, and the rate of building renovation is currently very low.

    The aim of this thesis is to investigate the economic and environmental aspects of energy renovation strategies, with two main objectives:

    • Renovation of Swedish district heated multi-family houses, including life-cycle cost and environmental analysis and impact on the local energy system;

    • Renovation of European residential and office buildings, including life-cycle cost and environmental analysis and influence of climatic conditions.

    Buildings typical for the respective regions and the period of construction 1945-1970 were simulated, in order to determine the feasibility and energy saving potential of energy renovation measures in European climates. A variety of systems for heating, cooling and ventilation were studied, as well as solar energy systems, with focus on heat pumps, district heating, low-temperature heating systems and air heat recovery.

    Compared to normal building renovation, energy renovation can often reduce the life-cycle costs and environmental impact. In renovation of typical European office buildings, as well as Southern European multi-family houses, more ambitious renovation levels can also be more profitable.

    Exhaust air heat pumps can be cost-effective complements in district heated multi-family houses, while ventilation with heat recovery is more expensive but also more likely to reduce the primary energy use. From a system perspective, simple exhaust ventilation can reduce the primary energy use in the district-heating plant as much as an exhaust air heat pump, due to the lower electricity use.

  • 15.
    Gustafsson, Marcus
    et al.
    Dalarna University, School of Technology and Business Studies, Energy Technology. KTH.
    Poppi, Stefano
    Dalarna University, School of Technology and Business Studies, Energy Technology. KTH.
    Bales, Chris
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Fedrizzi, Roberto
    Dipasquale, Chiara
    Bellini, Alessandro
    Ochs, Fabian
    Univeristy of Innsbruck.
    Dermentzis, Georgios
    Univeristy of Innsbruck.
    Performance of Studied Systemic Renovation Packages – Office Buildings2016Report (Other academic)
  • 16.
    Han, Mengjie
    et al.
    Dalarna University, School of Technology and Business Studies, Microdata Analysis.
    May, Ross
    Dalarna University, School of Technology and Business Studies, Microdata Analysis.
    Zhang, Xingxing
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Wang, Xinru
    Pan, Song
    Yan, Da
    Jin, Yuan
    A novel reinforcement learning method for improving occupant comfort via window opening and closingManuscript (preprint) (Other academic)
  • 17.
    Han, Mengjie
    et al.
    Dalarna University, School of Technology and Business Studies, Statistics.
    May, Ross
    Dalarna University, School of Technology and Business Studies, Microdata Analysis.
    Zhang, Xingxing
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Wang, Xinru
    Pan, Song
    Yan, Da
    Jin, Yuan
    Xu, Liguo
    A review of reinforcement learning methodologies for controlling occupant comfort in buildings2019In: Sustainable cities and society, ISSN 2210-6707, Vol. 51, article id 101748Article in journal (Refereed)
  • 18.
    Hersvall, Jacob
    Dalarna University, School of Technology and Business Studies, Construction.
    Tillämpning av Tekla Structura lDesigner: Enstudie med fokus på integration med Tekla Structural Designer som dimensioneringsverktyg2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Today, several 3D-Cad programs are used based on BIM application where detailed designs can be modeled to produce construction documents and manufacturing drawings around the engineering offices in Sweden. However, many of these programs are not compatible with 3D design and analysis software, but unnecessary work is required to draw a model several times to make the necessary calculations. The purpose of this degree project was to focus on the compatibility between Tekla Structural Designer and Tekla Structures, which also explored the ease of use of Tekla Structural Designer. The implementation was divided into two case studies, with the first focusing on the compatibility of a finished project model created in Tekla Structures as well as a separate model made in Tekla Structural Designer. In the second case study, the user-friendliness of the program was investigated in which the report describes how the user can utilize the most common features of the program. Based on case studies, they resulted in the compatibility between Tekla Structures and Tekla Structural Designer in both directions, although there are some limitations. An important conclusion from the work is that a model should preferably be projected with regard to being analytically correct before exporting from Tekla Structures. This in order to reduce hand laying at a later stage when the construction is to be analyzed. The application of Tekla Structural designs could lead to a more efficient working methodology within the projects. It could also lead to a closer relationship between projectors and those who perform the calculation when the projectors modeling models also have to think that the model should be analytically correct and be able to determine how elements etc. should be attached fixed or pinned. Furthermore, the program is considered useful in both modeling and analysis of a construction. Integration with several BIM software such as Autodesk Revit means that the application can be applied in several different projects

  • 19.
    Huang, Pei
    et al.
    City University of Hong Kong.
    Augenbroe, Godfried
    Huang, Gongsheng
    Sun, Yongjun
    Investigation of maximum cooling loss in a piping network using Bayesian Markov Chain Monte Carlo method2019In: Journal of Building Performance Simulation, Taylor & Francis, ISSN 1940-1493, E-ISSN 1940-1507, Vol. 12, no 2, p. 117-132Article in journal (Refereed)
  • 20.
    Huang, Pei
    et al.
    Dalarna University, School of Technology and Business Studies, Energy Technology. City University of Hong Kong.
    Fan, Cheng
    Zhang, Xingxing
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Wang, Jiayuan
    A hierarchical coordinated demand response control for buildings with improved performances at building group2019In: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 242, p. 684-694Article in journal (Refereed)
    Abstract [en]

    Demand response control is one of the common means used for building peak demand limiting. Most of the existing demand response controls focused on single building’s performance optimization, and thus may cause new undesirable peak demands at building group, imposing stress on the grid power balance and limiting the economic savings. A few latest studies have demonstrated the potential benefits of demand response coordination, but the proposed methods cannot be applied in large scales. The main reason is that, for demand response coordination of multiple buildings, associated computational load and coordination complexity, increasing exponentially with building number, are challenges to be solved. This study, therefore, proposes a hierarchical demand response control to optimize operations of a large scale of buildings for group-level peak demand reduction. The hierarchical control first considers the building group as a ‘virtual’ building and searches the optimal performance that can be achieved at building group using genetic algorithm. To realize such optimal performance, it then coordinates each single building’s operation using non-linear programming. For validations, the proposed method has been applied on a case building group, and the study results show that the hierarchical control can overcome the challenges of excessive computational load and complexity. Moreover, in comparison with conventional independent control, it can achieve better performances in aspects of peak demand reduction and economic savings. This study provides a coordinated control for application in large scales, which can improve the effectiveness and efficiency in relieving the grid stress, and reduce the end-users’ electricity bills.

  • 21.
    Huang, Pei
    et al.
    City University of Hong Kong.
    Huang, Gongsheng
    City University of Hong Kong.
    Building Automation for Energy Efficiency2019In: Handbook of Energy Efficiency in Buildings: A Life Cycle Approach / [ed] Umberto Desideri, Francesco Asdrubali, United Kingdom: Butterworth-Heinemann, 2019, 1, p. 627-649Chapter in book (Refereed)
    Abstract [en]

    In this chapter, the authors introduce current building energy management system (BEMS) from its development, current structure and main components, communications and standards, main functions and benefits, as well as future development trends. The information in this chapter can guide the readers in the direction of understanding, operation, and design of BEMS

  • 22.
    Huang, Pei
    et al.
    City University of Hong Kong.
    Huang, Gongsheng
    Investigation of maximum cooling loss uncertainty in piping network using Bayesian Markov Chain Monte Carlo method2017In: Energy Procedia, ISSN 1876-6102, E-ISSN 1876-6102, Vol. 143, p. 258-263Article in journal (Refereed)
    Abstract [en]

    Heating, Ventilation, and air-conditioning (HVAC) systems have been widely equipped in modern buildings to provide thermal comfort and acceptable indoor air quality, and always represent the largest primary energy end-use. As reported by many researchers, the cooling loss is prevalent in HVAC systems during cooling transmission from cooling sources (chillers) to cooling end-users (conditioning zones), and in some cases, it may even account for as high as 55% of the system total heat flow. At the design stage of an HVAC system, incomplete understanding of the cooling loss may lead to improper sizing of the HVAC system, which may result in additional energy consumption/economic cost (if oversized) or cause insufficient thermal comfort problems (if undersized). Therefore, the cooling loss in a typical HVAC system is significant, and it should be considered in the HVAC system sizing. For HVAC system sizing or retrofit, although there are many studies in the uncertainty in predicting the building peak cooling load, the uncertainty associated with the maximum cooling loss of the HVAC systems are still neglected. Therefore, this study proposes a study to investigate the uncertainty associated with the key parameters in predicting the maximum cooling loss in the HVAC systems using the Bayesian Markov Chain Monte Carlo method. The prior information of the uncertainty together with the available in-situ data is integrated to infer more informative posterior description of the uncertainty. The studied uncertain parameters can either be used for retrofit analysis or be used for prediction of the HVAC system performance. Details of the proposed methodology are illustrated by applying it to a real HVAC system.

  • 23.
    Huang, Pei
    et al.
    City University of Hong Kong.
    Huang, Gongsheng
    Augenbroe, Godfried
    Sizing heating, ventilating, and air-conditioning systems under uncertainty in both load-demand and capacity-supply side from a life-cycle aspect2017In: Science and Technology for the Built Environment, ISSN 2374-4731, E-ISSN 2374-474X, Vol. 23, no 2, p. 367-381Article in journal (Refereed)
  • 24.
    Huang, Pei
    et al.
    City University of Hong Kong.
    Huang, Gongsheng
    Augenbroe, Godfried
    Li, Shan
    Optimal configuration of multiple-chiller plants under cooling load uncertainty for different climate effects and building types2018In: Energy and Buildings, ISSN 0378-7788, E-ISSN 1872-6178, Vol. 158, p. 684-697Article in journal (Refereed)
    Abstract [en]

    Configuring the number and size of chillers in a multiple-chiller plant properly is an efficient way to improve the plant energy efficiency. At the design stage, the optimal configuration can be achieved through matching the capacity to load as closely as possible across the full-load profile. However, in spite of the fact that current literature offers practical recommendations, a systematic method to optimize the configuration of multiple-chiller plants is lacking. Due to the lack of accurate information at the design stage and only limited knowledge of the eventual realization it is hard to predict the building’s cooling load. Moreover, there is no operational data to predict the system performance. Both explain the existence of uncertainty in the HVAC plant design process. This paper, therefore, proposes a strategy to optimize the configuration of multiple-chiller plants, which takes account of the load side uncertainty as well as the COP uncertainty and selects the optimal configuration through a life-cycle analysis. Both the load side uncertainty and the COP uncertainty are quantified using statistical distributions. To facilitate applications, the distributions of the cooling load profile of different types of buildings under different weather conditions are investigated and are classified into four categories, and the optimal configuration schemes under each type of cooling load distribution are analyzed and summarized in a tabulated form.

  • 25.
    Huang, Pei
    et al.
    City University of Hong Kong.
    Huang, Gongsheng
    Sun, Yongjun
    A robust design of nearly zero energy building systems considering performance degradation and maintenance2018In: Energy, ISSN 0360-5442, E-ISSN 1873-6785, Vol. 163, p. 905-919Article in journal (Refereed)
    Abstract [en]

    Nearly zero energy buildings (nZEBs) are considered as a promising solution to mitigate the energy and environmental problems. A proper sizing of the nZEB systems (e.g. HVAC systems, PV panels, wind turbines and batteries) is essential for achieving the desirable level of thermal comfort, energy balance and grid dependence. Parameter uncertainty, component degradation and maintenance are three crucial factors affecting the nZEB system performances and should be systematically considered in system sizing. Until now, there are some uncertainty-based design methods been developed, but most of the existing studies neglect component degradation and maintenance. Due to the complex impacts of degradation and maintenance, proper sizing of nZEB systems considering multiple criteria (i.e. thermal comfort, energy balance and grid dependence) is still a great challenge. This paper, therefore, proposes a robust design method of nZEB systems using genetic algorithm (GA) which takes into account the parameter uncertainty, component degradation and maintenance. The nZEB life-cycle cost is used as the fitness function, and the user’ performance requirements on thermal comfort, energy balance and grid dependence are defined as three constraints. This study can help improve the designers’ understanding of the impacts of uncertainty, degradation, and maintenance on the nZEB life-cycle performances. The proposed method is effective in minimizing the nZEB life-cycle cost through designing the robust optimal nZEB systems sizes and planning the optimal maintenance scheme, meanwhile satisfying the user specified constraints on thermal comfort, energy balance, and grid dependence during the whole service life.

  • 26.
    Huang, Pei
    et al.
    City University of Hong Kong.
    Huang, Gongsheng
    Sun, Yongjun
    Uncertainty-based life-cycle analysis of near-zero energy buildings for performance improvements2018In: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 213, p. 486-498Article in journal (Refereed)
    Abstract [en]

    Near-zero energy buildings (nZEBs) are considered as an effective solution to mitigating CO2 emissions and reducing the energy usage in the building sector. A proper sizing of the nZEB systems (e.g. HVAC systems, energy supply systems, energy storage systems, etc.) is essential for achieving the desired annual energy balance, thermal comfort, and grid independence. Two significant factors affecting the sizing of nZEB systems are the uncertainties confronted by the building usage condition and weather condition, and the degradation effects in nZEB system components. The former factor has been studied by many researchers; however, the impact of degradation is still neglected in most studies. Degradation is prevalent in energy components of nZEB and inevitably leads to the deterioration of nZEB life-cycle performance. As a result, neglecting the degradation effects may lead to a system design which can only achieve the desired performance at the beginning several years. This paper, therefore, proposes a life-cycle performance analysis (LCPA) method for investigating the impact of degradation on the longitudinal performance of the nZEBs. The method not only integrates the uncertainties in predicting building thermal load and weather condition, but also considers the degradation in the nZEB systems. Based on the proposed LCPA method, a two-stage method is proposed to improve the sizing of the nZEB systems. The study can improve the designers’ understanding of the components’ degradation impacts and the proposed method is effective in the life-cycle performance analysis and improvements of nZEBs. It is the first time that the impacts of degradation and uncertainties on nZEB LCP are analysed. Case studies show that an nZEB might not fulfil its definition at all after some years due to component degradation, while the proposed two-stage design method can effectively alleviate this problem.

  • 27.
    Huang, Pei
    et al.
    City University of Hong Kong.
    Huang, Gongsheng
    Wang, Yu
    HVAC system design under peak load prediction uncertainty using multiple-criterion decision making technique2015In: Energy and Buildings, ISSN 0378-7788, E-ISSN 1872-6178, Vol. 91, p. 26-36Article in journal (Refereed)
    Abstract [en]

    Heating, ventilation and air-conditioning (HVAC) systems are widely equipped in modern buildings to provide indoor thermal comfort and guarantee indoor air quality. In a conventional design, the components of an HVAC system are sized according to a deterministic peak load, predicted according to typical weather condition, building physics and internal load. It has been shown by many studies that this prediction is associated with uncertainties since building physical parameters cannot be accurately set and the weather and the internal load used in the design may be different from the real situation after use. Therefore, uncertainty cannot be neglected in order to properly size a HVAC system. In this paper, a prototype of HVAC system design under uncertainty is proposed, which is able to take uncertainty directly in the design, and most importantly it can assess the performance of a design at the design stage in term of multiple performance indices and the customers’ requirements and preferences, i.e. the new design method falls in the framework of multiple criteria decision making. Case studies are used to illustrate the design procedure, and the result is compared with that of a conventional design method.

  • 28.
    Huang, Pei
    et al.
    City University of Hong Kong.
    Sun, Yongjun
    A clustering based grouping method of nearly zero energy buildings for performance improvements2019In: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 235, p. 43-55Article in journal (Refereed)
    Abstract [en]

    Collaborations among nearly zero energy buildings (nZEBs) (e.g. renewable energy sharing) can improve nZEBs’ performance at the community level. To enable such collaborations, the nZEBs need to be properly grouped. Grouping nZEBs with similar energy characteristics merely brings limited benefits due to limited collaboration existed, while grouping nZEBs with diverse energy characteristics can bring more benefits. In the planning of nZEB communities, due to the large diversity of energy characteristics and computation complexity, proper grouping that maximizes the collaboration benefits is difficult, and such a grouping method is still lacking. Therefore, this paper proposes a clustering based grouping method to improve nZEB performance. Using the field data, the grouping method first identifies the representative energy characteristics by advanced clustering algorithms. Then, it searches the optimal grouping alternative of these representative profiles that has the optimal performance. For validation, the proposed grouping method is compared with two cases (the nZEBs are either not grouped or randomly grouped) in aspects of economic costs and grid interaction. The study results demonstrate that the proposed method can effectively improve nZEBs’ performances at the community level. The propose method can provide the decision makers a means to group nZEBs, which maximize the collaboration benefits and thus assists the planning of nZEB communities.

  • 29.
    Huang, Pei
    et al.
    City University of Hong Kong.
    Sun, Yongjun
    A collaborative demand control of nearly zero energy buildings in response to dynamic pricing for performance improvements at cluster level2019In: Energy, ISSN 0360-5442, E-ISSN 1873-6785, Vol. 174, p. 911-921Article in journal (Refereed)
    Abstract [en]

    Collaborations (e.g. renewable energy sharing) among nearly zero energy buildings can improve performances at cluster level. Demand response control is helpful to enable such collaborations. Existing studies have developed some dynamic pricing demand response control methods to reduce the nearly zero energy building cluster’ electricity bills and eliminate the power grid's undesirable peaks. However, in these controls the collaborations among buildings are not allowed/enabled, since each building interacts with the grid and there is no direct interaction among buildings. Meanwhile, for performance optimizations at building cluster level, the computation costs of these non-collaborative controls are excessively high especially as a number of buildings considered. Therefore, this study proposes a collaborative demand response of nearly zero energy buildings in response to dynamic pricing for cluster-level performance improvements. Considering the building cluster as one ‘lumped’ building, in which the renewable generations, energy demands and battery capacities of individual buildings are aggregated, the collaborative control first identifies the optimal performance at cluster level in response to the dynamic pricing. Then, based on the identified optimal performance, the proposed control coordinates individual buildings' operations using non-linear programming, thereby realizing the collaborations. For validation, the proposed collaborative demand response control is compared with a game-theory based non-collaborative demand response control. The developed control effectively reduces the cluster-level peak energy exchanges and electricity bills by 18% and 45.2%, respectively, with significant computational load reduction. This study will provide the decision makers a computation-efficient demand response control of nearly zero energy buildings which enables full collaborations and thus helps improve the performances.

  • 30.
    Huang, Pei
    et al.
    City University of Hong Kong.
    Sun, Yongjun
    A robust control of nZEBs for performance optimization at cluster level under demand prediction uncertainty2019In: Renewable energy, ISSN 0960-1481, E-ISSN 1879-0682, Vol. 134, p. 215-227Article in journal (Refereed)
    Abstract [en]

    Collaborations among nZEBs (e.g. renewable energy sharing and battery sharing) can improve the nZEBs' performance at the cluster level. To enable such collaborations, existing studies have developed many demand response control methods to control the operation of nZEB systems. Unfortunately, due to lack of consideration of demand prediction uncertainty, most of the demand response control methods fail to achieve the desired performance. A few methods have considered the impacts of uncertainty, but they merely perform simple and limited collaborations among nZEBs, and thus they cannot achieve the optimal performance at the cluster level. This paper, therefore, proposes a nZEB control method that enables full collaborations among nZEBs and takes account of the demand prediction uncertainty. The proposed robust control method first analyzes the demand prediction uncertainty, next optimizes the nZEB cluster operation under uncertainty, and then coordinates single nZEB's operation using the cluster operational parameters. The performance of the robust control has been studied and compared with a deterministic control. Case studies show that the robust control can effectively increase the cluster load matching and reduce the grid interaction with the demand prediction uncertainty existed. The proposed method can achieve robust performance improvements for the nZEB cluster in practice particularly as uncertainty exists.

  • 31.
    Huang, Pei
    et al.
    City University of Hong Kong.
    Wang, Yu
    Huang, Gongsheng
    Augenbroe, Godfried
    Investigation of the ageing effect on chiller plant maximum cooling capacity using Bayesian Markov Chain Monte Carlo method2016In: Journal of Building Performance Simulation, Taylor & Francis, ISSN 1940-1493, E-ISSN 1940-1507, Vol. 9, no 5, p. 529-541Article in journal (Refereed)
  • 32.
    Huang, Pei
    et al.
    City University of Hong Kong.
    Wang, Yu
    Sun, Yongjun
    Huang, Gongshend
    Review of uncertainty-based design methods of central air-conditioning systems and future research trends2019In: Science and Technology for the Built Environment, ISSN 2374-4731, E-ISSN 2374-474X, Vol. 25, no 7, p. 819-835Article in journal (Refereed)
  • 33.
    Huang, Pei
    et al.
    City University of Hong Kong.
    Wu, Hunjun
    Huang, Gongsheng
    Sun, Yongjun
    A top-down control method of nZEBs for performance optimization at nZEB-cluster-level2018In: Energy, ISSN 0360-5442, E-ISSN 1873-6785, Vol. 159, p. 891-904Article in journal (Refereed)
    Abstract [en]

    Nearly zero energy buildings (NZEBs) are considered as a promising solution to the mitigation of the energy problems. A proper control of the energy system operation of the nZEB cluster is essential for improving load matching, reducing grid interaction and reducing energy bills. Existing studies have developed many demand response control methods to adjust the operation of energy systems to improve performances. Most of these studies focus on optimizing performances at individual-nZEB-level while neglecting collaborations (e.g. energy sharing and battery sharing) between nZEBs. Only a few studies consider the collaborations and optimize the system operation at nZEB-cluster-level, yet they cannot take full advantage of nZEB collaborations as optimization is conducted in a bottom-up manner lacking global coordination. This paper, therefore, proposes a top-down control method of nZEBs for optimizing performances at the cluster level. The top-down control method first considers the nZEB cluster as ‘one’ and optimizes its energy system operation using the genetic algorithm (GA), and then it coordinates the operation of every single nZEB inside the cluster using non-linear programming (NLP). The top-down control enables collaborations among nZEBs by coordinating single nZEB's operations. Such collaborations can bring significant performance improvements in different aspects. For instance, in aspect of economic cost, the collaborations can reduce the high-priced energy imports from the grid by sharing the surplus renewable energy with nZEBs which have insufficient energy generations. The proposed top-down control has been compared with a traditional non-collaborative control. The study results show that the top-down control is effective in improving performances at cluster level.

  • 34.
    Janols, Henrik
    et al.
    Dalarna University, School of Technology and Business Studies, Construction.
    Wik, Tina
    Dalarna University, School of Technology and Business Studies, Construction.
    Nulägesanalys av passivhusbyggande i Sverige 20102012Report (Other academic)
    Abstract [sv]

    Byggsektorn slukar årligen ca 40 % av Sveriges totala energiförbrukning. Nya normer kräver energieffektivare bostäder. Normerna idag fokuserar enbart på driftkostnader och tar inte alls hänsyn till energiförbrukningen och koldioxidavtrycket som själva byggprocessen alstrar. Med höga driftvärden blir energiförbrukningen i byggskedet en liten procent men för passivhus, och ännu högre grad för plusenergihus, som förbrukar ytterst lite energi, blir tillverkningsenergin den avgörande miljöbelastningen. Ny teknik för att uppnå de nya kraven finns i viss utsträckning, men kännedom och kunskap om dem saknas då de fått otillräcklig spridning. En del tekniska lösningar befinner sig fortfarande i en utvecklingsprocess och är inte färdigutvecklade för en större produktion. Ambitionen med denna nulägesanalys och därtill lika inventeringsarbete har varit att fånga in de lösningar och tester som gjorts och ta del av utvärderingarna så att vi kan dra nytta utav dessa i vårt arbete. Denna sammanställning grundar sig på muntlig information vi tagit del av under studiebesöken, ritningar, beskrivningar, protokoll samt rapporter vi samlat in.

    Syfte

    Syftet med vår resa till nedanstående objekt var att ta reda på hur flerfamiljshus med passivhus standard är byggda. Vilka stomval har gjorts och av vilken anledning. Vi ville också ta reda på hur man klarat av täthetskraven i de olika projekten samt hur detta mätts. I många fall verkar det som om utformning och arkitektur glöms bort när man ska bygga passivhus som om passivhuskravet vore så betungande att god utformning inte är förening med det. Därför ville vi också bedöma byggnaderna från arkitektoniska aspekter då dessa är av stor vikt för en bra miljö.

  • 35.
    Johansson, Daniel
    Dalarna University, School of Technology and Business Studies, Construction.
    Jämförelse mellan energiberäkning med TMF Energi och IDA ICE -fallstudie för ett småhus2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    For each newly produced house, an energy calculation will be made in the production state and after the building has started to be used, a measurement will form the basis for the energy declaration. This is done to make demands on the energy consumption of the house, in order to reach the targets by 2020 and 2050. There are many different methods for calculating energy consumption. In this report, two energy calculation programs will be compared and look at how the energy usage responds to the solar radiation in the different methods. A hand calculation will be made to validate if the energy usage level is reasonable. The two programs are TMF Energy and IDA Indoor Climate and Energy (IDA ICE). The calculations are made on a standard house from the house supplier Fiskarhedenvillan. The method is based on having the same conditions and inputs in the different methods, so that the results can be compared and see how they differ from one another. The house will be placed differently to see how the orientation affects the energy consumption. The results for the simulations are close to each other and the hand calculation differs from the programs. Even if solar factors change in the different computer programs, results can be matched to form a pattern. The same patterns can be seen in the hand calculation, but with a greater deviation.

  • 36.
    Johansson, Tim
    et al.
    Dalarna University, School of Technology and Business Studies, Construction.
    Johansson, Jonas
    Dalarna University, School of Technology and Business Studies, Construction.
    Bo i Byn: Utformning av seniorbostad2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    What happens when an elderly person wants to sell the property and move on to something

    that is easier to handle? Are there opportunities for older people to live in the same city as

    before? What opportunities are there for elderly people who want to move to a smaller

    residence? Can a concept be drawn up just for this assignment?

    This degree project will address the problem of how elderly people face a challenge to get to

    a simpler accommodation that is more suited to the elderly for functional and maintenance

    purposes. The thesis is based on an ongoing project that takes place in Norr Amsberg, a small

    town three kilometer north of Borlänge.

    In this degree project, a qualitative method will be used which means no calculations is

    needed. Thus, facts will be gathered from interviews, research articles and statistics.

    Six people have been interviewed during this project. Those who have been interviewed are

    two scientists who are stationed in Falun, three older people who have passed sixty-five years

    of ages and finally the enthusiast who started whole project in Norr Amsberg. This provides a

    broad ground for the conclusions drawn in the report.

    A concept house has been drawn up during this time, taking account of the wishes of the

    interviewees as appearance, functional requirements and location. The house has all

    accessibility requirements that a modern home will have. The building that is produced is a

    concept and not the finished product.

    Important conclusions that have been made during this study are how important the housing

    design is and how it affects the elderly significantly more than is generally believed and that

    the need will increase significantly in terms of custom housing in the future. The importance

    of housing design and how it affects older people are some major key factors that all

    municipalities learn to address when planning a type of "senior housing" for elderly people.

  • 37.
    Joudi, Ali
    Dalarna University, School of Technology and Business Studies, Energy Technology. Linköpings universitet.
    Radiation properties of coil-coated steel in building envelope surfaces and the influence on building thermal performance2015Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Recent studies have shown that the optical properties of building exterior surfaces are important in terms of energy use and thermal comfort. While the majority of the studies are related to exterior surfaces, the radiation properties of interior surfaces are less thoroughly investigated. Development in the coil-coating industries has now made it possible to allocate different optical properties for both exterior and interior surfaces of steel-clad buildings. The aim of this thesis is to investigate the influence of surface radiation properties with the focus on the thermal emittance of the interior surfaces, the modeling approaches and their consequences in the context of the building energy performance and indoor thermal environment.

    The study consists of both numerical and experimental investigations. The experimental investigations include parallel field measurements on three similar test cabins with different interior and exterior surface radiation properties in Borlänge, Sweden, and two ice rink arenas with normal and low emissive ceiling in Luleå, Sweden. The numerical methods include comparative simulations by the use of dynamic heat flux models, Building Energy Simulation (BES), Computational Fluid Dynamics (CFD) and a coupled model for BES and CFD. Several parametric studies and thermal performance analyses were carried out in combination with the different numerical methods.

    The parallel field measurements on the test cabins include the air, surface and radiation temperatures and energy use during passive and active (heating and cooling) measurements. Both measurement and comparative simulation results indicate an improvement in the indoor thermal environment when the interior surfaces have low emittance. In the ice rink arenas, surface and radiation temperature measurements indicate a considerable reduction in the ceiling-to-ice radiation by the use of low emittance surfaces, in agreement with a ceiling-toice radiation model using schematic dynamic heat flux calculations.

    The measurements in the test cabins indicate that the use of low emittance surfaces can increase the vertical indoor air temperature gradients depending on the time of day and outdoor conditions. This is in agreement with the transient CFD simulations having the boundary condition assigned on the exterior surfaces. The sensitivity analyses have been performed under different outdoor conditions and surface thermal radiation properties. The spatially resolved simulations indicate an increase in the air and surface temperature gradients by the use of low emittance coatings. This can allow for lower air temperature at the occupied zone during the summer.

    The combined effect of interior and exterior reflective coatings in terms of energy use has been investigated by the use of building energy simulation for different climates and internal heat loads. The results indicate possible energy savings by the smart choice of optical properties on interior and exterior surfaces of the building.

    Overall, it is concluded that the interior reflective coatings can contribute to building energy savings and improvement of the indoor thermal environment. This can be numerically investigated by the choice of appropriate models with respect to the level of detail and computational load. This thesis includes comparative simulations at different levels of detail.

  • 38.
    Jäderbrink, Erik
    et al.
    Dalarna University, School of Technology and Business Studies, Construction.
    Isaksson, Lena
    Dalarna University, School of Technology and Business Studies, Construction.
    Kostnadseffektivisering av ett lågenergikoncept: En komponentjämförelse för småhus2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The aim of this degree thesis is to investigate and establish how the choice of components such as windows, entrance doors and HRV-units affect the energy demand and operating cost of a detached house.

    The Swedish company Fiskarhedenvillan currently offers two different concepts for detached houses; conventional houses and passive houses which comply with the German Passive House Institute (PHI).   The passive house concept (as set by PHI) puts high emphasis on not just low energy consumption but also on high comfort. With high demands come high investment costs. Fiskarhedenvillan wishes for the concept of the passive house to be modified to a nearly zero-energy building by replacing certified components with non-certified ditto with the intention to lower the investment costs.   The objective of this thesis degree is to develop a more cost efficient low-energy concept compared to the passive house according to PHI and this by making different choices concerning components. Two question formulations were made:

    • By what amount can the investment costs be reduced by changing components and how will the modification affect the energy demand?
    • Is it possible to develop a more cost efficient low-energy concept?

    The comparison research was made by using a control sample, projected to meet the demands set by PHI, as a reference.  A comparison was made by using the planning tool Passive House Planning Package together with data from the control sample. The variation in result between the control sample and the new alternatives was due only to choice of components. 

    The study resulted in two equally cost efficient combinations of components with regard to technical lifespan. Both combinations consist of non-certified windows and entrance doors but have the certified HRV-unit used in the controlled sample. Thus, the most cost efficient alternative consists of both certified and non-certified components.

    Conclusions:

    • The investment cost can be reduced by up to 59,1 % for components or 6,7 % for building kit with new components included. The energy demand increased by11 kWh/m². 
    • It is fully possible to develop a concept that is more cost efficient than Fiskarhedenvillan’s existing low-energy concept.
  • 39.
    Karlsson, Samuel
    Dalarna University, School of Technology and Business Studies, Construction.
    Husgrunders miljöpåverkan: Jämförelse av grundläggningsmetoder för ett småhus2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Buildings affect the environment and climate in many ways, not only during the

    operating stage, but also during production. While buildings are constructed to

    be more energy-effective, a greater share of the buildings total energy demand

    will depend on how the building is produced. Previous studies show that

    buildings with a frame made of wood has substantially lower energy demand and

    greenhouse gas emissions due to production than building frames made of

    concrete. The aim with this report is to investigate the environmental effects due

    to different methods for foundation of a detached house. The main focus is to

    calculate the energy consumption and emissions of carbon dioxide equivalents

    from production of materials. Three different constructions are compared;

    foundation with cellular glass (The Koljern-method), a concrete slab, and a post

    and pier foundation with a wood-based floor. By designing the three

    constructions to be equal in terms of ability to carry the load from a two story

    house 8X12m, and with equal U-values, the comparison is made out of the

    required use of materials. Data for use of energy and CO2e-emissions” from

    cradle to gate” has been taken from declarations on the building products,the

    ICE database and EPD-documents for the various materials. Thereafter, the

    total use of energy and emissions of CO2e has been calculated. Assessments

    from the SundaHus database is also studied to get a more detailed picture of the

    environmental impact and health aspects of the materials.

    The result shows that the post and pier foundation has the lowest use of energy

    in production of the materials and a negative release of greenhouse gas due to

    sequestration. The foundation made of cellular glass has the highest demand of

    energy for producing the materials for the foundation, and a concrete slab has

    the highest emissions of greenhouse gas.

    From estimations made by SundaHus, no further conclusions could be made

    due to the use of environmentally and health restricted materiel. The deduction

    is that the post and pier foundation can be an interesting alternative to reduce

    the carbon footprint from the production of building foundation, but to get a better

    overview a total lifecycle analysis has to be made.

  • 40.
    Knutz, Lars
    Dalarna University, School of Technology and Business Studies, Construction.
    Energibehovsanalys av passiva massivträhus2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis is based on a project which created a test building designed to advance and improve passive houses. The so-called “test building” can help to evaluate different scenarios for moisture transport and tightness. The test building has advanced HVAC systems to control temperature and moisture levels, which makes the test building a good tool to check if theoretical energy calculation formulas match reality.

    The aim of this thesis was partly to investigate how different energy calculation programs match reality and each other, as well as to investigate if the test building fulfills its goal of being classified as a passive house. The method used was based on energy calculations made by hand as well as four different energy calculation programs on the computer. These were compared with each other and with real energy measurements from the test building.

    From the results of the energy calculations the following conclusions could be made; the comparison between the programs shows a difference of up to 12 kWh/m2, yr or 8 % between the highest and lowest results. The electricity consumption of the household and the habits of the inhabitants has a large influence on the result. The comparison between measured energy usage and calculated energy usage is < 15%. Here there is an uncertainty between the weather data used in the calculations and the real weather data. The test building cannot fulfill the claim of a passive house at 150m2 that have a central heating system installed today.

  • 41.
    Kovacs, Peter
    et al.
    RISE Research Institutes of Sweden.
    Dahlenbäck, Jan-Olof
    Chalmers University of Technology .
    Fiedler, Frank
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Tvärfackligt projekt ger branschen ökad kunskap om solcellstak vid takrenovering2019In: Husbyggaren, ISSN 0018-7968, Vol. 3, p. 8-11Article in journal (Other (popular science, discussion, etc.))
    The full text will be freely available from 2020-06-24 14:57
  • 42.
    Kuhn, Tillmann
    et al.
    Fraunhofer ISE.
    Fath, Karoline
    Fraunhofer ISE.
    Bales, Chris
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Gustafsson, Marcus
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Nouvel, Romain
    ZAFH.
    Fedrizzi, Roberto
    EURAC.
    D2.3 RES availability survey and boundary conditions for simulations2014Report (Other academic)
  • 43.
    Ljungdahl, Therese
    et al.
    Dalarna University, School of Technology and Business Studies, Construction.
    Caroline, Norrström
    Dalarna University, School of Technology and Business Studies, Construction.
    Utveckling av träregelvägg anpassad förframtida energikrav2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Various proposals on wooden joist walls are presented in this report, forFiskarhedenvillan’s standard wall. Boverket has issued a new referral where the energyrequirements for houses has been intensified and become more accurate, depending tothe county and city. The climate zones have been replaced by an adjustment factor.The aim is to develop four new improved wall structures and to do moisture simulations toinvestigate how the constructions are able to be exposed to moisture. The walls should fitinto the company's system solutions.The insulation alternatives that are studied are rock wool and cellulose insulation.Tests are made in the degree thesis to see what would happen if the vapour barrier isreplaced with a thicker OSB and also if the exterior gypsum is replaced by a“Västkustskiva”. Although a thicker construction with cellulose insulation is developed.Calculations and simulations are made to see if the wall structures passed the energyrequirement, depending on house-style and geographical location.Three of Fiskarhedenvillan’s houses were investigated based on two locations, Lund andUmeå.The investigation resulted that all wall structures passed the moisture simulations andalso did the walls pass the coming energy requirements set in Boverket’s referral.Three of the walls has very similar U-value but are different in thickness and insulationmaterials.The conclusion is that the structure of cellulose insulation and OSB got the best results inall areas. The wall:

    • has the lowest U-value, which means a low energy consumption
    • manufactured from recycled materials
    • economically feasible to Fiskarhedenvillan’s customers
  • 44.
    May, Ross
    Dalarna University, School of Technology and Business Studies, Microdata Analysis.
    The reinforcement learning method: A feasible and sustainable control strategy for efficient occupant-centred building operation in smart cities2019Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Over half of the world’s population lives in urban areas, a trend which is expected to only grow as we move further into the future. With this increasing trend in urbanisation, challenges are presented in the form of the management of urban infrastructure systems. As an essential infrastructure of any city, the energy system presents itself as one of the biggest challenges. As cities expand in population and economically, global energy consumption increases and as a result so do greenhouse gas (GHG) emissions. To achieve the 2030 Agenda’s sustainable development goal on energy (SDG 7), renewable energy and energy efficiency have been shown as key strategies for attaining SDG 7. As the largest contributor to climate change, the building sector is responsible for more than half of the global final energy consumption and GHG emissions. As people spend most of their time indoors, the demand for energy is made worse as a result of maintaining the comfort level of the indoor environment. However, the emergence of the smart city and the internet of things (IoT) offers the opportunity for the smart management of buildings. Focusing on the latter strategy towards attaining SDG 7, intelligent building control offers significant potential for saving energy while respecting occupant comfort (OC). Most intelligent control strategies, however, rely on complex mathematical models which require a great deal of expertise to construct thereby costing in time and money. Furthermore, if these are inaccurate then energy is wasted and the comfort of occupants is decreased. Moreover, any change in the physical environment such as retrofits result in obsolete models which must be re-identified to match the new state of the environment. This model-based approach seems unsustainable and so a new model-free alternative is proposed. One such alternative is the reinforcement learning (RL) method. This method provides a beautiful solution to accomplishing the tradeoff between energy efficiency and OC within the smart city and more importantly to achieving SDG 7. To address the feasibility of RL as a sustainable control strategy for efficient occupant-centred building operation, a comprehensive review of RL for controlling OC in buildings as well as a case study implementing RL for improving OC via a window system are presented. The outcomes of each seem to suggest RL as a feasible solution, however, more work is required in the form of addressing current open issues such as cooperative multi-agent RL (MARL) needed for multi-occupant/multi-zonal buildings.

  • 45.
    Myhren, Jonn Are
    Department of Fluid and Climate Technology, School of Technology and Health, KTH, Alfred Nobels Allé 10, SE-14152 Huddinge, Stockholm, Sweden.
    Improving the thermal performance of ventilation radiators: The role of internal convection fins2011In: International journal of thermal sciences, ISSN 1290-0729, E-ISSN 1778-4166, Vol. 50, no 2, p. 115-123Article in journal (Refereed)
    Abstract [en]

    This paper deals with heat output optimization of a ventilation radiator by varying the distribution of vertical longitudinal convection fins. A ventilation radiator, which combines ventilation air supply and heat emission to the room, has a higher driving force on air in between the radiator panels compared to traditional radiators and can for this reason have more heat transferring surfaces to improve thermal efficiency. Improving the thermal efficiency means a lower water temperature is required for heating and energy can be saved in production and distribution of heat in systems with heat pumps, district heating or similar.

    The investigation was made using Computational Fluid Dynamics (CFD) simulations while analytical calculations were used for verification of different flow and heat transfer mechanisms. Results showed that heat transfer can be increased in the section where ventilation air is brought into the room by slightly changing the geometry of the fins, decreasing the fin to fin distance and cutting off a middle section of the fin array. This change in internal design could mean considerable increase in thermal efficiency for the ventilation radiator as a whole.

  • 46.
    Myhren, Jonn Are
    et al.
    Department of Fluid and Climate Technology, School of Technology and Health, KTH, Alfred Nobels Allé 10, SE-14152 Huddinge, Stockholm, Sweden.
    Holmberg, Sture
    Department of Fluid and Climate Technology, School of Technology and Health, KTH, Alfred Nobels Allé 10, SE-14152 Huddinge, Stockholm, Sweden.
    Design considerations with ventilation-radiators: Comparisons to traditional two-panel radiators2009In: Energy and Buildings, ISSN 0378-7788, E-ISSN 1872-6178, Vol. 41, no 1, p. 92-100Article in journal (Refereed)
  • 47.
    Myhren, Jonn Are
    et al.
    Dalarna University, School of Technology and Business Studies, Construction.
    Holmberg, Sture
    Performance evaluation of ventilation radiators2013In: Applied Thermal Engineering, ISSN 1359-4311, E-ISSN 1873-5606, Vol. 51, no 1-2, p. 315-324Article in journal (Refereed)
    Abstract [en]

    A ventilation radiator is a combined ventilation and heat emission unit currently of interest due to its potential for increasing energy efficiency in exhaust ventilated buildings with warm water heating. This paper presents results of performance tests of several ventilation radiator models conducted under controlled laboratory conditions.

     

    The purpose of the study was to validate results achieved by Computational Fluid Dynamics (CFD) in an earlier study and indentify possible improvements in the performance of such systems. The main focus was on heat transfer from internal convection fins, but comfort and health aspects related to ventilation rates and air temperatures were also considered.

      The general results from the CFD simulations were confirmed; the heat output of ventilation radiators may be improved by at least 20 % without sacrificing ventilation efficiency or thermal comfort.

     

    Improved thermal efficiency of ventilation radiators allows a lower supply water temperature and energy savings both for heating up and distribution of warm water in heat pumps or district heating systems. A secondary benefit is that a high ventilation rate can be maintained all year around without risk for cold draught.

  • 48.
    Nouvel, Romain
    et al.
    ZAFH.
    Cotrado, Mariela
    ZAFH.
    Bertesina, Diego
    Manens.
    Bales, Chris
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Birchal, Sarah
    Fedrizzi, Roberto
    D4.2 Assessed Standardised Energy Generation and Energy Distribution Packages2016Report (Other academic)
  • 49.
    Ochs, Fabian
    et al.
    Univeristy of Innsbruck.
    Fedrizzi, Roberto
    Bales, Chris
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Dermentzis, Georgios
    Univeristy of Innsbruck.
    D6.7 Guidelines on Systemic Approach and Checklist2016Report (Other academic)
  • 50. Sun, Yongjun
    et al.
    Huang, Pei
    City University of Hong Kong.
    Huang, Gongsheng
    A multi-criteria system design optimization for net zero energy buildings under uncertainties2015In: Energy and Buildings, ISSN 0378-7788, E-ISSN 1872-6178, Vol. 97, p. 196-204Article in journal (Refereed)
    Abstract [en]

    Net zero energy buildings (NZEBs) have been widely considered to be an effective solution to the increasing energy and environmental problems. Most conventional design methods for NZEB systems are based on deterministic data/information and have not systematically considered the significant uncertainty impacts. Consequently, the conventional design methods lead to popular oversized problems in practice. Meanwhile, NZEB system design methods need to consider customers’ actual performance preferences but few existing methods can take account of them. Therefore, this study proposes a multi-criteria system design optimization for NZEBs under uncertainties. In the study, three performance criteria are used to evaluate the overall NZEB system performance based on user-defined weighted factors. Case studies are conducted to demonstrate the effectiveness of the proposed method.

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