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  • 51.
    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)
  • 52.
    Fiedler, Frank
    et al.
    Dalarna University, School of Technology and Business Studies, Energy and Environmental Technology.
    Bales, Chris
    Dalarna University, School of Technology and Business Studies, Energy and Environmental Technology.
    Persson, Tomas
    Dalarna University, School of Technology and Business Studies, Energy and Environmental Technology.
    Optimisation method for solar heating systems in combination with pellet boilers/stoves2007In: International Journal of Green Energy, ISSN 1543-5075, E-ISSN 1543-5083, Vol. 4, no 3, p. 325-337Article in journal (Refereed)
    Abstract [en]

    In this study an optimisation method for the design of combined solar and pellet heating systems is presented and evaluated. The paper describes the steps of the method by applying it for an example system. The objective of the optimisation was to find the design parameters that give the lowest auxiliary energy (pellet fuel + auxiliary electricity) and carbon monoxide (CO) emissions for a system with a typical load, a single family house in Sweden. Weighting factors have been used for the auxiliary energy use and CO emissions to give a combined objective function. Different weighting factors were tested. The results show that extreme weighting factors lead to their own minima. However, it was possible to find factors that ensure low values for both auxiliary energy and CO emissions, and suitable weighting factors are suggested.

  • 53.
    Fiedler, Frank
    et al.
    Dalarna University, School of Technology and Business Studies, Environmental Engineering.
    Bales, Chris
    Dalarna University, School of Technology and Business Studies, Environmental Engineering.
    Persson, Tomas
    Dalarna University, School of Technology and Business Studies, Environmental Engineering.
    Nordlander, Svante
    Comparison of carbon monoxide emissions and electricity consumption of modulating and non-modulating pellet and solar heating systems2007In: International journal of energy research (Print), ISSN 0363-907X, E-ISSN 1099-114X, Vol. 31, no 10, p. 915-930Article in journal (Refereed)
    Abstract [en]

    Emission and electricity consumption are important aspects of a pellet heating system. Low noxious emissions, particularly carbon monoxide, are a measure of a well-performing system. High carbon monoxide emissions are often caused by unnecessary cycling of the burner, poor adjustment of the combustion air and insufficient maintenance. The carbon monoxide output, the thermal performance and the electricity consumption for modulating and non-modulating operation mode have been investigated by simulations of four stoves/boilers as part of combined solar and pellet heating systems. The systems have been modelled with the simulation programme TRNSYS and simulated with the boundary conditions for space heating demand, hot water load and climate data as used in earlier research projects. The results from the simulations show that operating the pellet units with modulating combustion power reduces the number of starts and stops but does not necessarily reduce the carbon monoxide output. Whether the carbon monoxide output can be reduced or not depends very strongly on the reduction of starts and stops and how much the carbon monoxide emissions increase with decreased combustion power, which are in turn dependent on the particular settings of each pellet burner and how the heat is transferred to the building. However, for most systems the modulating operation mode has a positive impact on carbon monoxide emissions. Considering the total auxiliary energy demand, including the electricity demand of the pellet units, the modulating combustion control is advantageous for systems 1 and 4 for the used boundary conditions. The study also shows that an appropriate sizing of the stove or boiler has a huge potential for energy saving and carbon monoxide emission reduction.

  • 54.
    Fiedler, Frank
    et al.
    Dalarna University, School of Technology and Business Studies, Energy and Environmental Technology.
    Bales, Chris
    Dalarna University, School of Technology and Business Studies, Energy and Environmental Technology.
    Vestlund, Johan
    Dalarna University, School of Technology and Business Studies, Energy and Environmental Technology.
    Monitoring results of combined pellet and solar heating system2007In: ISES Solar World Congress 2007, ISES 2007, 2007, Vol. 2, p. 867-871Conference paper (Other academic)
    Abstract [en]

    In this study the monitoring results of prototype installation of a recently developed solar combisystem have been evaluated. The system, that uses a water jacketed pellet stove as auxiliary heater, was installed in a single family house in Borlänge/Sweden. In order to allow an evaluation under realistic conditions the system has been monitored for a time period of one year. From the measurements of the system it could be seen that it is important that the pellet stove has a sufficient buffer store volume to minimize cycling. The measurements showed also that the stove gives a lower share of the produced heat to the water loop than measured under stationary conditions. The solar system works as expected and covers the heat demand during the summer and a part of the heat demand during spring and autumn. Potential for optimization exists for the parasitic electricity demand. The system consumes 680 kWh per year for pumps, valves and controllers which is more than 4% of the total primary heating energy demand.

  • 55.
    Fiedler, Frank
    et al.
    Dalarna University, School of Technology and Business Studies, Environmental Engineering.
    Nordlander, Svante
    Dalarna University, School of Technology and Business Studies, Environmental Engineering.
    Persson, Tomas
    Dalarna University, School of Technology and Business Studies, Environmental Engineering.
    Bales, Chris
    Dalarna University, School of Technology and Business Studies, Environmental Engineering.
    Thermal performance of combined solar and pellet heating systems2006In: Renewable energy, ISSN 0960-1481, E-ISSN 1879-0682, Vol. 31, no 1, p. 73-88Article in journal (Refereed)
    Abstract [en]

    Various pellet heating systems are marketed in Sweden, some of them in combination with a solar heating system. Several types of pellet heating units are available and can be used for a combined system. This article compares four typical combined solar and pellet heating systems: System 1 and 2 with a pellet stove, system 3 with a store integrated pellet burner and system 4 with a pellet boiler. The often lower efficiency of pellet heaters compared to oil or gas heaters increases the final energy demand. Consequently heat losses of the various systems have been studied. The systems have been modeled in TRNSYS and simulated with parameters identified from measurements. For almost all systems the flue gas losses are the main heat losses except for system 3 where store heat losses prevail. Relevant are also the heat losses of the burner and the boiler to the ambient. Significant leakage losses are noticed for system 3 and 4. For buildings with an open internal design system 1 is the most efficient solution. Other buildings should preferably apply system 2 or 3. The right choice of the system depends also on whether the heater is placed inside or outside of the heated area. Unlike the expectations and results from other studies, the operation of the pellet heaters with modulating combustion power is not necessarily improving the performance. A large potential for system optimization exists for all studied systems, which when applied could alter the relative merits of the different system types.

  • 56.
    Fiedler, Frank
    et al.
    Dalarna University, School of Technology and Business Studies, Energy and Environmental Technology.
    Persson, Tomas
    Dalarna University, School of Technology and Business Studies, Energy and Environmental Technology.
    Annual CO-emissions of combined pellet and solar heating systems2007In: ISES Solar World Congress 2007, ISES 2007, 2007, Vol. 4, p. 2468-2472Conference paper (Other academic)
    Abstract [en]

    Emissions are an important aspect of a pellet heating system. High carbon monoxide emissions are often caused by unnecessary cycling of the burner when the burner is operated below the lowest combustion power. Combining pellet heating systems with a solar heating system can significantly reduce cycling of the pellet heater and avoid the inefficient summer operation of the pellet heater. The aim of this paper was to study CO-emissions of the different types of systems and to compare the yearly CO-emissions obtained from simulations with the yearly CO-emissions calculated based on the values that are obtained by the standard test methods. The results showed that the yearly CO-emissions obtained from the simulations are significant higher than the yearly CO-emissions calculated based on the standard test methods. It is also shown that for the studied systems the average emissions under these realistic annual conditions were greater than the limit values of two Eco-labels. Furthermore it could be seen that is possible to almost halve the CO-emission if the pellet heater is combined with a solar heating system.

  • 57.
    Fleyeh, Hasan
    Dalarna University, School of Technology and Business Studies, Computer Engineering.
    Traffic Signs Color Detection and Segmentation in Poor Light Conditions2005In: Machine Vision Applications (MVA2005), Tsukuba Science City, 2005Conference paper (Refereed)
    Abstract [en]

    This paper presents a new algorithm for color detection and segmentation of road signs in poor light conditions. The images were taken by a digital camera mounted in a car. The RGB channels of the digital images were enhanced separately by histogram equalization, and then a color constancy algorithm was applied to extract the true colors of the sign. The resultant image was then converted into HSV color space, and segmented to extract the colors of the road signs. The method was tested on outdoor images in different poor light conditions such as fog and snow, and they show high robustness. This project is part of the research taking place at Dalarna University - Sweden in the field of the Intelligent Transport Systems (ITS).

  • 58.
    Franzon, Joffe
    Dalarna University, School of Technology and Business Studies, Construction.
    Hur en armerad betongbalk dimensioneras för hål i livet2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In the design stage, conflicts between installations and bodies often arise. In multi-story

    buildings huge profits can be made from being able to make holes in concrete beams in

    order to carry an installation through the beam. But the knowledge of how the beam is to

    be dimensioned for larger holes is not generally known.

    Two concrete manuals with different calculation methods have therefore been analyzed to

    evaluate which of these could be the basis for a calculation template. The prerequisites

    were defined as beams without prestressed concrete, with rectangular cross-sections and

    square or rectangular holes.

    The Mathcad calculation program was used to make two calculation templates for the

    Swedish and Norwegian methods. As a calculation example, dimensions and loads were

    used from an experimental study in Egypt 2005. In that study, the beam was exposed to

    loads that brought it to failure. Their theoretical failure capacity was in line with the

    practical values.

    A comparison of the amount of reinforcement and execution was made between the three

    different models. It turned out that the Norwegian model was the most similar to the

    Egyptian. The reinforcement of the Norwegian model was the most similar to that of the

    Egyptian model, but the amount of reinforcement was slightly less.

    The Swedish model was not considered reliable for design purposes. As the Norwegian

    model had a little less reinforcement, it was considered necessary to add a safety factor or

    perform a load capacity test in order to ensure the beam’s capacity.

  • 59.
    Fredin, Andreas
    et al.
    Dalarna University, School of Technology and Business Studies, Construction.
    Snöborgs, Oscar
    Dalarna University, School of Technology and Business Studies, Construction.
    Energimässig och kostnadsmässig jämförelse av FTX och FX system i landet: Jämförelse av två alternativa renoverings lösningar för värmeåtervinning i flerbostadshus2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This report includes an energy- and geographical comparison between two alternative renovation solutions for heat recovery in apartment buildings. The survey includes a typical apartment building that is representative of the ‘Miljon Program’, and was carried out because of the ongoing debate about which system works best for the renovation of apartment buildings. The project work was carried out with simulations through an Excel-based program called TMF Energy 2.2 developed by SP, Sweden’s Technical Research Institute.

    he purpose of this project was to develop two geographical representations of Sweden that would show where in the country the two different ventilation and heat recovery systems worked most efficiently regarding primary energy and energy costs for heating.

    The results showed that there was no threshold, boundary of grey area in the country, one of the systems was more efficient in terms of primary energy use and the other system was more energy cost efficient.

    The discussion section of this report includes a variety of topics such as primary energy factors, how to manage requirements, why airtightness affects the systems differently and energy costs for district heating.

    The conclusions that were drawn from the results includes that the FTX-system is the most primary energy efficient and that the FX-system is the most energy cost efficient. There was no boundary or grey area in the country for the chosen building, and the FTX-system is affected more by varying airtightness than the FX-system.

  • 60.
    Frid, Mikael
    Dalarna University, School of Technology and Business Studies, Construction.
    Solcellsdrivet FTX-system för miljonprogramshus: Tjärna Ängar, Borlänge2013Independent thesis Advanced level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The project is a feasibility study of including the installation of solar cells and an FTX ventilation system in the renovation of a Swedish million program multi-family ouse. The question concerns whether the energy production of the PV system can match with the energy consumption of the FTX-system. Input data was obtained from:

    • Databases, literature and interviews.
    • Simulations of photovoltaics modules in the computer program PVSYST
    • Modulation of the vents in the computer program MagiCAD

    The aim was primarily to investigate whether it was possible to get a theoretical working system. The economy of the project should also be investigated depending on the results.

    The study showed that it should be theoretically possible to install photovoltaics for electricity generation that is able to cover the FTX system's electricity needs on a yearly basis. The photovoltaics are also expected to produce enough electricity for some other equipment that requires electricity for much of the year. It was also found that it should be possible to get the photovoltaics modules economically viable if a pay-back time of 14 years was used. The method used for these results is thoroughly described and with small changes applicable to a large number of buildings in the Swedish building stock.

    An important conclusion from the project is that if property owner can see 14 years into the future with an investment in solar energy, there is much to be gained. There are already skills, available technologies and products available in order to recover a large portion of the properties' electricity needs through solar energy.

  • 61.
    Gesar, Daniel
    et al.
    Dalarna University, School of Technology and Business Studies, Construction.
    Hansson, Erik
    Dalarna University, School of Technology and Business Studies, Construction.
    Uppvärmningslösningars klimat- och resurspåverkan i Dalarna: Jämförelse mellan fjärrvärme och andra uppvärmningslösningars klimat- och resurspåverkan beroende på renoveringsstrategi och geografisk placering i Dalarna2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    För att nyttja jordens resurser på bästa sätt är det viktigt att använda rätt energityp till dess mest effektiva ändamål. Att energieffektivisera och minska utsläppen av växthusgaser är något som har fått mycket uppmärksamhet under 2000-talet och är fortsatt en högt prioriterad fråga i dagens samhälle.

    Detta examensarbete syftar till att jämföra byggnaders klimat- och resurspåverkan inom Dalarnas fjärrvärmenät. Genom olika renoveringssenarier påverkas en byggnads primärenergianvändning och utsläpp av koldioxid olika beroende på vart i Dalarna den är placerad. I arbetet ingår även en jämförelse av vanliga värmesystem jämfört med Dalarnas kommuners fjärrvärmesystem. Vid jämförelserna användes data från en byggnadssimulering för att simulera olika förhållanden i byggnaden. Beräkningar och jämförelser av resultaten belyser vilka faktorer som har stor inverkan på energianvändning, utsläpp samt vilka åtgärder som ger den bästa förändringen.

    Resultaten visar att variationen är stor mellan fjärrvärmesystemen i Dalarnas kommuner och de olika värmesystemen, där kommunernas bränslemix har en stor inverkan på resultatet. Bränslen med höga primärenergifaktorer leder till en stor ökning av primärenergianvändningen. Eftersom el har en hög primärenergifaktor är det viktigt att minimera elanvändningen. Renoveringsresultaten tyder på att en sänkning av inomhustemperaturen ger den största förändringen i primärenergianvändning och koldioxidutsläpp. Att installera en frånluftsvärmepump till fjärrvärmesystemet är överlag sämre ur miljösynpunkt. Att byta till en oljepanna är mycket dåligt i samtliga kommuner medan en pelletspanna kan minska koldioxidutsläppen i stora kommuner.

  • 62.
    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.

  • 63.
    Gustafsson, Annica
    et al.
    Dalarna University, School of Technology and Business Studies, Construction.
    Granberg, Per
    Dalarna University, School of Technology and Business Studies, Construction.
    Energieffektivisering av klimatskal i tropiskt klimat: Fallstudie av en byggnad i Surabaya, Indonesien2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Studien omfattar en undersökning av en byggnad i Surabaya, Indonesien

    belägen på universitet UBAYA. Användningen av luftkonditionering ökar kraftigt i

    utvecklingsländer. Detta gör att behovet av förbättringar i såväl

    klimatanläggningar som i byggnader kommer att vara nödvändiga för att inte

    orsaka ytterligare påfrestningar på miljön genom ökad energianvändning

    Syftet med studien är att hitta energibesparande åtgärder på byggnadens

    klimatskal med hänsyn till det tropiska klimatet utan att orsaka fuktproblem i

    ingående byggnadsdelar.

    Byggnaden fungerar i dagsläget bra ur fuktsynpunkt och har inga direkt synliga

    skador orsakade av fuktproblem i konstruktionen. Däremot påvisar det höga uvärdet

    för byggnaden dess ineffektivitet gällande energibehov. Fyra olika

    åtgärdsförslag med utgångspunkt i den nuvarande konstruktionen presenteras i

    studien. Åtgärdsförslagen utvärderas ur fuktsynpunkt med programmet WUFI

    samt ur ett energimässigt perspektiv med programmet Polysun.

    Resultatet visar att störst energibesparing kan ske genom att isolera taket då det

    visar sig vara en stor värmekälla till byggnaden. Denna åtgärd innebär samtidigt

    en viss risk för fuktproblem på grund av höga relativa fukthalter och

    temperaturer. Även en tätning av de nuvarande läckagen i byggnaden påverkar

    energiförbrukningen i stor utsträckning, vilket gör dessa två åtgärder till den

    bästa kombinationen för att sänka energiförbrukningen. Att byta ut nuvarande

    englaskassetter mot tvåglas samt isolera de befintliga ytterväggarna är de

    åtgärder som påverkar energibehovet minst.

    Några av de slutsatser som dras ur studien är att totalt sett kan byggnadens

    energiförbrukning sänkas med 50 % om samtliga åtgärdsförslag genomförs.

    Fuktriskerna ökar vid isoleringsåtgärder men är genomförbara.

  • 64.
    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.

  • 65.
    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.

  • 66.
    Gustafsson, Marcus
    et al.
    Dalarna University, School of Technology and Business Studies, Energy Technology. KTH.
    Ochs, Fabian
    Univeristy of Innsbruck.
    Birchall, Sarah
    Dermentzis, Georgios
    Univeristy of Innsbruck.
    Bales, Chris
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Calabrese, Toni (Contributor)
    University of Innsbruck.
    Report on auditing tool for assessment of building needs2015Report (Other academic)
  • 67.
    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)
  • 68.
    Gustafsson, Marcus
    et al.
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Swing Gustafsson, Moa
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Myhren, Jonn Are
    Dalarna University, School of Technology and Business Studies, Construction.
    Bales, Chris
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Holmberg, Sture
    Techno-economic analysis of energy renovation measures for a district heated multi-family house2016In: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 177, p. 108-116Article in journal (Refereed)
    Abstract [en]

    Renovation of existing buildings is important in the work toward increased energy efficiency and reduced environmental impact. The present paper treats energy renovation measures for a Swedish district heated multi-family house, evaluated through dynamic simulation. Insulation of roof and façade, better insulating windows and flow-reducing water taps, in combination with different HVAC systems for recovery of heat from exhaust air, were assessed in terms of life cycle cost, discounted payback period, primary energy consumption, CO2 emissions and non-renewable energy consumption. The HVAC systems were based on the existing district heating substation and included mechanical ventilation with heat recovery and different configurations of exhaust air heat pump.Compared to a renovation without energy saving measures, the combination of new windows, insulation, flow-reducing taps and an exhaust air a heat pump gave up to 24% lower life cycle cost. Adding insulation on roof and façade, the primary energy consumption was reduced by up to 58%, CO2 emissions up to 65% and non-renewable energy consumption up to 56%. Ventilation with heat recovery also reduced the environmental impact but was not economically profitable in the studied cases. With a margin perspective on electricity consumption, the environmental impact of installing heat pumps or air heat recovery in district heated houses is increased. Low-temperature heating improved the seasonal performance factor of the heat pump by up to 11% and reduced the environmental impact.

  • 69.
    Haberl, Robert
    et al.
    Institute for Solar Technology SPF, HSR University of Applied Sciences, Switzerland.
    Haller, Michell Y.
    Institute for Solar Technology SPF, HSR University of Applied Sciences, Switzerland.
    Papillon, Philippe
    CEA INES, France.
    Chèze,, David
    CEA INES, France.
    Persson, Tomas
    Dalarna University, School of Technology and Business Studies, Energy and Environmental Technology.
    Bales, Chris
    Dalarna University, School of Technology and Business Studies, Energy and Environmental Technology.
    Testing of combined heating systems for small houses: Improved procedures for whole system test methods: Deliverable 2.32015Report (Other academic)
    Abstract [en]

    Dynamic system test methods for heating systems were developed and applied by the institutes SERC and SP from Sweden, INES from France and SPF from Switzerland already before the MacSheep project started. These test methods followed the same principle: a complete heating system – including heat generators, storage, control etc., is installed on the test rig; the test rig software and hardware simulates and emulates the heat load for space heating and domestic hot water of a single family house, while the unit under test has to act autonomously to cover the heat demand during a representative test cycle. Within the work package 2 of the MacSheep project these similar – but different – test methods were harmonized and improved. The work undertaken includes: 

    • Harmonization of the physical boundaries of the unit under test.

    • Harmonization of the boundary conditions of climate and load.

    • Definition of an approach to reach identical space heat load in combination with an autonomous control of the space heat distribution by the unit under test.

    • Derivation and validation of new six day and a twelve day test profiles for direct extrapolation of test results.

     

    The new harmonized test method combines the advantages of the different methods that existed before the MacSheep project. The new method is a benchmark test, which means that the load for space heating and domestic hot water preparation will be identical for all tested systems, and that the result is representative for the performance of the system over a whole year. Thus, no modelling and simulation of the tested system is needed in order to obtain the benchmark results for a yearly cycle. The method is thus also applicable to products for which simulation models are not available yet.

    Some of the advantages of the new whole system test method and performance rating compared to the testing and energy rating of single components are: 

    • Interaction between the different components of a heating system, e.g. storage, solar collector circuit, heat pump, control, etc. are included and evaluated in this test.

    • Dynamic effects are included and influence the result just as they influence the annual performance in the field.

    • Heat losses are influencing the results in a more realistic way, since they are evaluated under "real installed" and representative part-load conditions rather than under single component steady state conditions.

     

    The described method is also suited for the development process of new systems, where it replaces time-consuming and costly field testing with the advantage of a higher accuracy of the measured data (compared to the typically used measurement equipment in field tests) and identical, thus comparable boundary conditions. Thus, the method can be used for system optimization in the test bench under realistic operative conditions, i.e. under relevant operating environment in the lab.

     

    This report describes the physical boundaries of the tested systems, as well as the test procedures and the requirements for both the unit under test and the test facility. The new six day and twelve day test profiles are also described as are the validation results.

  • 70.
    Hallenberg, Josefin
    et al.
    Dalarna University, School of Technology and Business Studies, Industrial Engineering and Management.
    Bergström, Jonas
    Dalarna University, School of Technology and Business Studies, Industrial Engineering and Management.
    Konceptet mobilitet som tjänst: Viktiga kompetenser och möjliga utmaningar vid vidareutvecklingen av MaaS i Sverige.2016Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Transport and travel is necessary for our society to function. Today, the privately owned car stands for more than half of all personal trips in Sweden. In the last couple of years researchers have highlighted the idea that personal transport is facing a paradigm shift, which means a reduction in the use and dependent of the privately owned car and an increased focus on individuals buying their Mobility as a Service (MaaS). MaaS is described as an integrated mix of different mobility services which are arranged in the form of customized mobility packages to the customer. These mobility packages can be compared to a mobile phone subscription, which includes various mobility services, such as train, bus, subway, taxi, carpool, etc. in various amounts depending on the individual's changing needs. The individual can take care of their own travel planning, booking and payment via an app in their smartphone. What distinguish MaaS from other mobility services is that the customer can travel from door-to-door instead of a predefine station to another.

    There have been various Maas projects around the world in order to increase understanding of the concept of MaaS, there is still a lot of unanswered questions and researchers would like to see more studies in the field, in order to find factors that are important and vital to the concept MaaS.

    The aim of the thesis is to: Discuss some competences that may be significant for the further development of the concept Maas in Sweden and discuss potential challenges that may arise at further development of the concept MaaS in Sweden.

    This study is based on previous research and experiences and thoughts on the concept MaaS from various stakeholders with knowledge and experience of the concept.

    This study has an abductive approach. Primary data were obtained through qualitative semistructured interviews with eight people who have knowledge and experience of the Maas.

    The main conclusions in this study is that the competences that are most important in the development of MaaS is collaborative skills and competences required to create an attractive mobility package based on customer needs.

    One challenge identified in this study is the challenge of creating individualized mobility package in which different types of mobility services are integrated. Another challenge can arise when public and private organizations collaborate and when new organizations enter the transport network and try to cooperate with the established organizations

  • 71.
    Hammar, Mimmi
    Dalarna University, School of Technology and Business Studies, Construction.
    Utformning av arbetsmetod för betongreparationer med PPA, preplaced aggregate2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Vanlig betong består av ballast, cement, vatten och eventuellt tillsatsmedel. Detta

    blandas samman till en homogen massa som sedan placeras i form där det härdar

    under värmeutveckling. Under härdningen uppstår krympningar i cementen som

    orsakar spänningar. Genom att använda sig av större andel ballast i betongen kan

    krympningen reduceras.

    Fram till 1980-talet var en metod där ballasten först packades i en gjutform och sedan

    injekterades med cementbruk som band samman stenarna vanlig för att bygga och

    reparera betongkonstruktioner. Denna betong kallas bland annat för

    injekteringsbetong, two-stage concrete eller preplaced aggregate (PPA). Genom

    reparationen av Gamla Årstabrons valv 2007 fick PPA-betong en pånyttfödelse då

    reparationen krävde en betong med minimal krympning för att krympspänningarna

    inte skulle slita sönder underliggande konstruktion.

    Vid byggandet av Citybanans järnvägsbro, som sträcker sig mellan Älvsjö och

    Årstaberg i Stockholm, upptäcktes skador på undersidan av de balkar som gjutits för

    att bära delar av spårbanan. Dessa skador behövde åtgärdas och beställaren,

    Trafikverket, valde att reparera bron med PPA. Tack vare entreprenören E-Schakt har

    författaren fått möjligheten att följa arbetet med PPA-reparationerna och

    sammanställa denna rapport vars syfte var att utveckla arbetsmetoden och försöka

    hitta alternativa lösningar till utförandet.

    Arbetet genomfördes genom platsbesök och intervjuer med personer som bidrog med

    information, erfarenheter och nyttiga infallsvinklar. En litteraturstudie gjordes för att

    samla grundläggande information om vilka egenskaper betong och PPA har och hur

    dessa egenskaper påverkar utförandet

    Rapporten visar att form utav plexiglas och en helt rund ballast skulle kunna förenkla

    arbetet och förbättra resultatet. Dessutom framkommer att samarbete, engagemang

    och gemensam uppfattning om varför just PPA används är viktigt för ett lyckat

    slutresultat.

  • 72.
    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)
  • 73.
    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
    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)
  • 74.
    Hanses, Axel
    et al.
    Dalarna University, School of Technology and Business Studies, Construction.
    Brossberg, Klas
    Dalarna University, School of Technology and Business Studies, Construction.
    Infästningsmetoder för prefabricerade fasadelement2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    It was approximately 50 years ago since the houses from the miljonprogram era

    were built. Today many of these houses are in need of renovation. The energy

    usages in these buildings are very high, and many changes need to happen for

    them to meet the modern standards of energy useage in buildings.

    One way to decrease the energy usage is to attach prefabricated facades

    to buildings, to lower the building envelopes heat transmission coefficient.

    This study’s purpose is to find suitable attachment methods for Dalahus

    prefabricated facade elements.

    The study started with researching common multi-family residential

    buildings from the miljonprogram era. After reviewing constructional drawings over

    the chosen buildings, it became apparent that it would be complicated to attach

    the elements without doing any preparatory work on the building, something that

    BioInnovation wants to avoid.

    The study then continued with researching past projects, with prefabricated

    facade renovations, to see what kind of methods were used. Three different kinds

    of attachment methods that met BioInnovations standards were developed. Using

    a method which requires as little preparatory work as possible.

    The foundation method uses Lecablocks placed in the ground, as a

    foundation for the elements. The second technique uses L-profiles that are

    attached to the walls, whereas the third method uses a rail where the elements

    hang on.

    Calculations were made to see if the methods worked and could handle the

    forces from the elements. The result of this study shows that lamellarhouses with

    L-profiles are the most suitable attachment method

  • 75.
    Hellström, Emma
    et al.
    Dalarna University, School of Technology and Business Studies, Construction.
    Maleki, Benjamin
    Dalarna University, School of Technology and Business Studies, Construction.
    Kondensrisk i frånluftsfläkt för behovsstyrd ventilation: En experimentell undersökning2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In Sweden it is very common for villas and small houses to have an uninsulated

    attic, a so called cold attic. Installing a demand-controlled ventilation system is a

    way to increase energy efficiency in both old and newly built houses. To be able

    to place an exhaust fan in a cold attic in a nordic climate, where temperatures

    reaches twenty degrees below zero, some type of insulation is not uncommonly

    required to prevent condensation from forming inside the unit. The purpose of

    this study has been to investigate how thick the insulation needs to be around

    the fan to prevent from condensation, depending on temperature. The

    investigation have been done in the climate chamber at the university of

    Dalarna. To ensure the right climate an exhaust fan with insulated conduits was

    installed to create one damp indoor- and one colder outdoor environment to

    conducted tests at different temperatures with different levels of insulation. The

    study shows that insulation is required, at what temperatures and what levels of

    insulation we can expect condensation to form and what is required to prevent

    condensation from forming. The results from these tests could aid in preventing

    moisture problems that could occur when installing a demand-controlled

    ventilation system.

  • 76.
    Henning, Annette
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Indoor climate agreements in energy-efficiency and renovation projects - a question of justice?2018In: Proceedings of the Ises Eurosun 2018 Conference - 12th International Conference on Solar Energy for Buildings and Industry / [ed] Haberle A, 2018, p. 1694-1703Conference paper (Refereed)
    Abstract [en]

    One of the global dilemmas of our time is the urgent need to reduce energy demand in some parts of the world and at the same time manage to increase and improve energy services in others. This paper calls attention to the importance of also recognizing local energy dilemmas and pockets of more vulnerable groups in energy efficiency and building renovation projects. Interviews with tenants in a Swedish ‘million-program’ housing area are used to illustrate the arguments in the paper. Results show essential variations in male and female thermal sensation. They also show little compatibility between the tenants’ wishes for a comfortable home and the housing company’s energy saving ambitions. The paper argues that the use of generalized indoor climate agreements needs to be taken less for granted and complemented with qualitative investigations of all main actors in a specific local context. Only then can possible disparities become evident, and alternative, more just, solutions be worked out.

  • 77.
    Henning, Annette
    et al.
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Sattari, Amir
    Dalarna University, School of Technology and Business Studies, Construction.
    Evaluating thermal comfort in a Swedish block of flats: A methodological comparison2017Conference paper (Refereed)
    Abstract [en]

    Two methodological approaches have been used to investigate thermal comfort amongoccupants in a Swedish block of flats; measurements and thermal comfort standards on the onehand, and qualitative interviews on the other. The purpose with this paper is to present, compareand discuss results from these two radically different methods. The results coincide concerningvariations of thermal comfort throughout the day, but are much less in accord in results whereoccupants express, or are presumed to complain of, thermal discomfort. The interviews showthat female occupants tend to suffer more from thermal discomfort than male occupants, a resultwhich is absent in the measurement methodology. The results give support to suggestions thatgender aspects should be taken more into account when determining and controlling thermalcomfort. The differing results also point at the importance of complementing standardizedthermal comfort measurements with surveys or qualitative interviews.

  • 78.
    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

  • 79.
    Hesaraki, Arefeh
    et al.
    KTH.
    Myhren, Jonn Are
    Dalarna University, School of Technology and Business Studies, Construction.
    Holmberg, Sture
    KTH.
    Influence of different ventilation levels on indoor air quality and energy savings: a case study of a single-family house2015In: Sustainable cities and society, ISSN 2210-6707, Vol. 19, p. 165-172Article in journal (Refereed)
    Abstract [en]

    The influence of different ventilation levels on indoor air quality (IAQ) and energy savings were studied experimentally and analytically in a single-family house occupied by two adults and one infant, situated in Borlänge, Sweden. The building studied had an exhaust ventilation system with a range of air flow rate settings. In order to find appropriate ventilation rates regarding CO2, relative humidity (RH) and temperature as indicators of IAQ, four ventilation levels were considered, as follows: (I) A very low ventilation rate of 0.10 L s-1 m-2; (II) A low ventilation rate of 0.20 L s-1 m-2; (III) A normal ventilation rate of 0.35 L s-1 m-2; (IV) A high ventilation rate of 0.70 L s-1 m-2. In all cases, the sensor was positioned in the exhaust duct exiting from habitable spaces. Measurements showed that, for case I, the CO2 concentration reached over 1300 ppm, which was higher than the commonly referenced threshold for ventilation control, i.e. 1000 ppm, showing unacceptable IAQ. In case II, the CO2 level was always below 950 ppm, indicating that 0.20 L s-1 m-2 is a sufficient ventilation rate for the reference building. The case III showed that the ventilation rate of 0.35 L s-1 m-2 caused a maximum CO2 level of 725 ppm; showing the level recommended by Swedish regulations was high with respect to CO2 level. In addition, measurements showed that the RH and temperature were within acceptable ranges in all cases. An energy savings calculation showed that, in case II, the comparative savings of the combined energy requirement for ventilation fan and ventilation heating were 43% compared with case III.

  • 80.
    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)
  • 81.
    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

  • 82.
    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.

  • 83.
    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)
  • 84.
    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.

  • 85.
    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.

  • 86.
    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.

  • 87.
    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.

  • 88.
    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.

  • 89.
    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.

  • 90.
    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.

  • 91.
    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)
  • 92.
    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)
  • 93.
    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.

  • 94.
    Husanov, Fuad
    Dalarna University, School of Technology and Business Studies, Construction.
    Kunskap hos privatpersoner om termisk komfort inomhus: En fallstudie av kunskapen om termisk komfort2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Thermal comfort indoors is a big factor in how you feel comfortable in your home. It is important to know how individuals are experiencing their thermal comfort indoors. To get there you must also find out how much knowledge they have for thermal climate, as this may affect the way they behave to control their experience of the thermal climate in their homes.

    The aim is answered on the following issues

    • How much

    knowledge individuals have about thermal comfort

    • What are the problem areas that might arise based on measurements taken of each home

    • Is there a connection between how much knowledge they have on their residence and higher risk of

    poor thermal comfort

    • The proportion of satisfied / dissatisfied with their thermal comfort

    and to compare measurements to results of the interview.

    The individuals were found to have thorough knowledge of the thermal climate and differed between the different home. In total 13 people are in interviewed which includes 5 houses. Homeowners were found to have more knowledge than those who lived in apartment. But no one knew which factors influence thermal environment other than trim level and the temperature of the air. There were two residents that had problems and higher risk of illness. You could also see a link between low knowledge of the thermal climate and the higher risk of poor thermal climate. It turned out that the majority were satisfied with the thermal climate in their homes. What was interesting, however, was that those who had too warm indoors were still satisfied while those who had it a bit too chilly were dissatisfied. According PMV index that I got was that both parties should be dissatisfied. One possible explanation for this not being the case could be that when you have it too warm in the winter indoors then you have a greater opportunity to cool down the house by lighter clothing, reducing the temperature of the radiator or open the balcony door so that it comes in fresh air while also cooling the house. All this are free from charge.

    While for those who has a bit too chilly can not control the temperature free of charge during winter.

    According to measurements, the carbon dioxide content are normal in all houses except the above mentioned which had too high levels. The house with high carbon dioxide content also had slightly higher relative humidity, which was 41.5% which is higher than others, in comparison. The temperature was within reasonable levels but some had air temperature below 20C

    0. After looking at the house, I found a possible cause of high carbon dioxide content. They had closed the air ducts that sat across the windows in the belief that it would lead to warmer housing. Although house 1, which had the air temperature of about 20.3C0, they felt cool at home. The cause of that was long curtains that hung and covered the radiator, which could rub the heat circulation and the distribution of heat. Although house 1 who had air temperature about 20.3C0, felt chilly at home. Sick Building Syndrome house was also investigated and a very likely cause were found in house ventilation system.

    In this theses it has shown that the majority is satisfied with their thermic comfort, but the minority is over 30 %.

    This investigation is clearly showing problem areas with thermal climate which can occur and the need of informing house owners of thermal climate to avoid any problem caused by them.

  • 95.
    Hägerby, Daniel
    et al.
    Dalarna University, School of Technology and Business Studies, Energy and Environmental Technology.
    Karlsson, Mikael
    HVV.
    V2G backup Skid-VM 20152012Report (Other academic)
    Abstract [sv]

    2015 kommer Skid-VM att hållas i Falun. TV-bolagen kräver redundant kraft som standard för denna typ av arrangemang. Detta sköts normalt med dieselgeneratorer och eventuellt UPS:er. För att utreda detaljerna kring, och möjligheterna med, att ersätta några eller alla dieselgeneratorer med elkraft från elfordon, har en förstudie gjorts under 2011.

    Denna studie tittat djupare på några sätt att göra detta. Slutsatsen är att tekniken finns och är mogen nog att klara uppgiften, men intresset hos fordonstillverkarna är svagt.

  • 96.
    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.

  • 97.
    Jansson, Tom
    Dalarna University, School of Technology and Business Studies, Construction.
    Utvärdering av terrester laserskanning i framställandet av en 3D-modell: Baserat på underlag från ritning och terrester laserskanning av en fackverksbro2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In recent years, the implementation of building information modeling (BIM) in the Swedish civil engineering industry has increased. This is due to directives from the government stating that the Swedish Transport Administration (Trafikverket), in greater occurrence, will benefit from the digital possibilities with the BIM concept. Trafikverket is the government agency responsible for the long-term planning and management of public roads, construction in the infrastructure such as tunnels and bridges, and has great influence in the Swedish civil engineering industry. They claim that the key to enhance the use and development of BIM is to raise their demands towards the rest of the industry. Transitioning from a drawing-based to an object-based approach will affect the entire industry. The idea is to be able to handle all the information in 3D-data and the BIM concept throughout the entire life cycle of the construction. To reach that ambition, the already-built constructions need to be represented as 3D-models in terms of being a part of the BIM concept.

    Terrestrial laser scanning is a method of measurement that is being used worldwide for 3D-documentation of complex objects and environments. The result of a scan is comprehensive with low uncertainty of measurement; therefore the method is well suited to assist in the creation of 3D-models.

    The primary aim of the study is to examine the differences between 3D-models, depending on the measurement method that was used to create them.

    An analysis of the current situation in these fields-of-study was made by a literature study to place this thesis in its proper context. Although the two 3D-models were the same exact object, they were created using two different methods of measurement. The models were compared to identify the differences between them.

    The study unveils that the choice of measurement method influences the results of the 3D-model, where the terrestrial laser scanning method could help to improve the quality of the final product. On the other hand, there were areas where the two methods of measurement could complement each other for even better results.

  • 98.
    Janérs, Jenny
    Dalarna University, School of Technology and Business Studies, Construction.
    Kommunikation mellan arbetsledning och yrkesarbetare: En kartläggning över informationsflödet på arbetsplatsen2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Background: Inadequate communication has for a long time, cost both time and money for the construction industry. Large savings can be made by the construction companies by improving the communication. Improvements can be made both internally, by the organization, and externally between the client and the contractor.

    Purpose: The main purpose of the study is to make a survey of the information flow between project management and professional workers and to locate the weaknesses related to the communication. Those studies and results will give additional grounds to improve the communication within NCC.

    Restrictions: The study was limited to only be done within NCC:s department Infrastructure in Dalarna and manage three ongoing projects. Restrictions were also made to only manage the internal communication between project management and professional workers in the projects.

    Method: In the start phase, a survey of how the information is spread internally within NCC today, what information channels are used and how communication is conducted between project management and professional workers. This by: review follow-ups on projects, participate in meetings and join the professional workers on site.

    Interviews were made with the project management and professional workers. Finally, the shortcomings of the results are presented. The identified problems can later form the basis of a development model in communication, for both project management and professional workers at NCC.

    Result: Shows that some are happy with the communication in the projects while others are not entirely satisfied with the way the communication is handled in the workplace.

    Conclusion: Some of the conclusions obtained from the thesis work are as follows:

    o For a project to be a successful project, both in cost and time, it is necessary to clarify who will participate in the project from start to finish.

    o Closer cooperation and daily communication between professional workers and project management not only lead to less misunderstandings but also to effective and innovative solutions to both execution as a whole and the problems that arise along the way.

  • 99.
    Jia, Tao
    et al.
    Wuhan University.
    Håkansson, Johan
    Dalarna University, School of Technology and Business Studies, Information Systems. Dalarna University, School of Technology and Business Studies, Human Geography.
    To what extent are CO2 emissions from intra-urban shopping trips by cars affected by drivers’ travel behaviour and store location?2016Report (Other academic)
    Abstract [en]

    Transportation is seen as one of the major sources of CO2 pollutants nowadays. The impact of increased transport in retailing should not be underestimated. Most previous studies have focused on transportation and underlying trips, in general, while very few studies have addressed the specific affects that, for instance, intra-city shopping trips generate. Furthermore, most of the existing methods used to estimate emission are based on macro-data designed to generate national or regional inventory projections. There is a lack of studies using micro-data based methods that are able to distinguish between driver behaviour and the locational effects induced by shopping trips, which is an important precondition for energy efficient urban planning. The aim of this study is to implement a micro-data method to estimate and compare CO2 emission induced by intra-urban car travelling to a retail destination of durable goods (DG), and non-durable goods (NDG). We estimate the emissions from aspects of travel behaviour and store location. The study is conducted by means of a case study in the city of Borlänge, where GPS tracking data on intra-urban car travel is collected from 250 households. We find that a behavioural change during a trip towards a CO2 optimal travelling by car has the potential to decrease emission to 36% (DG), and to 25% (NDG) of the emissions induced by car-travelling shopping trips today. There is also a potential of reducing CO2 emissions induced by intra-urban shopping trips due to poor location by 54%, and if the consumer selected the closest of 8 existing stores, the CO2 emissions would be reduced by 37% of the current emission induced by NDG shopping trips.

  • 100. Jin, Y.
    et al.
    Yan, D.
    Zhang, Xingxing
    Dalarna University, School of Technology and Business Studies, Energy Technology.
    Han, Mengjie
    Dalarna University, School of Technology and Business Studies, Microdata Analysis.
    Kang, X.
    An, J.
    Sun, H.
    District household electricity consumption pattern analysis based on auto-encoder algorithm2019In: IOP Conference Series: Materials Science and Engineering, 2019, Vol. 609, no 7, article id 072028Conference paper (Refereed)
    Abstract [en]

    The energy shortage is one key issue for sustainable development, a potential solution of which is the integration with the renewable energy resources. However, the temporal sequential characteristic of renewable resources is different from traditional power grid. For the entire power grid, it is essential to match the energy generation side with the energy consumption side, so the load characteristic at the energy use side is crucial for renewable power integration. Better understanding of energy consumption pattern in buildings contributes to matching different source of energy generation. Under the background of integration of traditional and renewable energy, this research focuses on analysis of different household electricity consumption patterns in an urban scale. The original data is from measurement of daily energy consumption with smart meter in households. To avoid the dimension explosion phenomenon, the auto-encoder algorithm is introduced during the clustering analysis of daily electricity use data, which plays the role of principal component analysis. The clustering based on auto-encoder gives a clear insight into the urban electricity use patterns in household. During the data analysis, several feature variables are proposed, which include peak value, valley value and average value. The distinction analysis is also conducted to evaluate the analysis performance. The study takes households in Nanjing city, China as a case study, to conduct the clustering analysis on electricity consumption of residential buildings. The analysis results can be further applied, such as during the capacity design of district energy storage.

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