| 1. |
- Jansson, Gustav, et al.
(author)
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Requirements transformation in construction design
- 2010
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In: CIB W78 27th International Conference on Applications of IT in the AEC Industry & Accelerating BIM Research Workshop.
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Conference paper (other academic/artistic)abstract
- Transformation of performance requirements to technical solutions and production parameters is central for architects and engineers in the design process. Construction industry suffers from low efficiency in design, and the information flow creating bottlenecks for the production process. Tracing and managing information through design process needs standards both for requirements and Building Information Models in a life cycle perspective. Structuring functional requirements is of great interest for the construction industry and especially for companies developing industrialised housing system that often have control over the whole manufacturing process. The delivery of a new low-carbon economy in Europe puts pressure on the construction industry to reduce the energy consumption for buildings. Therefore is one national standard for energy requirements tested on a building system and evaluated in an Information and Communication Technology-environment (ICT) that supports the design process for industrialised construction. The result of the research shows that the transformation of requirements to technical solutions needs functionality that supports the design process by using standards for requirements. A rigid building system based on well defined design tasks together with a technical platform, both for spaces and physical elements, work as a backbone for development of ICT support systems. Product Life Cycle Support (PLCS), as a standard that enables flexibility in categorisation of information through the construction design.
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| 2. |
- Lidberg, Tina, 1982-
(author)
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Building Energy Efficiency Measures in District Heating Systems
- 2020
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Doctoral thesis (other academic/artistic)abstract
- Improving energy performance of existing buildings is an important part in decreasing energy use and in turn reducing greenhouse gas emissions and primary energy use. To be able to evaluate how energy refurbishment influences greenhouse gas emissions and primary energy use a wider system perspective is needed which puts the building in its context. This thesis deals with energy efficiency refurbishment performed on multi-family buildings within district heated areas and how greenhouse gas emissions and primary energy use is influenced. Both energy demand and temperature levels are considered.A simulated building is used to evaluate energy refurbishment packages. The results are used as input data for models of district heating systems to cost optimize district heating production. One district heating system model is also used to evaluate the impact of lowered district heating supply temperatures. The results from the cost optimizations are used to evaluate the impact on greenhouse gas emissions and primary energy use.The results show that all refurbishment packages decreases greenhouse gas emissions and primary energy use, but to a different extent. Depending on the fuel types used and to which extent electricity is co-produced in the district heating system, the results of implementing the refurbishment packages vary. The largest reduction of greenhouse gas emissions and primary energy use occurs in a district heating system with a high share of biofuel and no electricity production. Another result is that the temperature levels of a building’s heating system can be reduced when refurbished which promotes low-temperature district heating. The results also indicates that greenhouse gas emissions and primary energy use can be decreased from a short- and medium term perspective if the supply temperature of a district heating system is lowered. From a long term perspective primary energy use is still decreased while greenhouse gas emissions are increased.
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| 3. |
- Lidberg, Tina, 1982-
(author)
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Influences from Building Energy Efficiency Refurbishment on a Regional District Heating System
- 2018
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Licentiate thesis (other academic/artistic)abstract
- Improving energy performance of existing buildings is an important part in decreasing energy use and in turn reduce the greenhouse gas emissions caused by human activity and the primary energy use.To be able to evaluate how energy refurbishment influences the greenhouse gas emissions and the primary energy use a wider system perspective is needed that puts the building in its context. This thesis deals with energy refurbishment packages performed on multi-family buildings within district heated areas and how they influence greenhouse gas emissions and primary energy use when the district heating use is altered.A simulated building is used to evaluate several energy refurbishment packages. The results are used as input data for models of district heating systems to cost optimize the district heating production. The results from the cost optimization are used to evaluate the impact on greenhouse gas emissions and primary energy use.The results show a difference between measures that saves district heating without increasing the use of electricity and measures that increases the use of electricity while district heating is saved. For example, a building refurbishment package including only building envelope improvements saves the same amount of district heating as a package including only mechanical ventilation with heat recovery. Despite this, the emissions of greenhouse gases and the use of primary energy is to a greater extent reduced in the first package because the use of electricity remains unchanged.Comparing energy refurbishment packages performed on the same building, but within different district heating systems, show the importance of the design of the district heating system. Depending on the fuel types used and to which extent electricity is co-produced in the district heating system, the results of implementing the energy refurbishment packages vary. The largest reduction of greenhouse gases and primary energy use occurs when a refurbishment package is performed on a building in a district heating system with high share of biofuel and no electricity production.
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| 4. |
- Norberg, Håkan, et al.
(author)
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Byggsynkronisering
- 2009
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Reports (other academic/artistic)abstract
- Rapporten redovisar de resultat som hittills framkommit i ett ERABUILD-projekt där avsikten är att skapa industrialiserade processer för definition, utformning, byggande och fastighetsförvaltning som väsentligt kan effektivisera byggande och förvaltning av fastigheter över hela livscykeln. Målet med den svenska delen är att definiera en framtida industrialiserad byggprocess som är stödd av ett synkroniserat flöde av information, resurser, material och aktiviteter till byggplatsens olika produktionsställen. Hypotesen är att platsknutna planeringsmetoderna som Line of Balance och 4D tillsammans med en robust produktionsstyrningsmetod kan skapa arbetsscheman som kan genomföras med tillräcklig förutsägbarhet. Detta är nödvändigt för att kunna skapa bra och effektiva försörjningskedjor. Mobila verksamhetssystem är en lämplig teknologi för att kunna understödja ett sådant synkroniserat byggande. För att säkerställa en öppen tillgång till den gemensamma bygginformationsmiljön (VBE) kommer tekniken med standardiserade Web Services att testas för att koppla ihop applikationer som kan stödja ett synkroniserat byggande.I Etapp I av projektet har produktionsprocessen för en typisk byggplats kartlagts där informations- och materialflöden samt användning av gemensamma resurser nödvändiga för genomförandet av olika produktionsaktiviteter definierats för att utveckla en byggplatsanpassad logistikmodell. Applikationer och metoder för planering och styrning samt strategier och mått för byggplatsens försörjningskedjor av information, material och komponenter har identifierats. I Etapp II, har valda delar av modellen att jämförts och utvärderas mot traditionella metoder i ett pågående byggprojekt, (NCC:s projekt kvarteret Rådjuret i Luleå samt Solberga Torg). Framtagna metoder med stöd av valda applikationer har demonstreras i en avgränsad del av projektet. Idag implementeras 3D projektering i stor skala i den svenska byggbranschen. Detta har lett till bättre samordning mellan olika discipliner och mindre antal kollisioner som måste lösas på plats. I nästa steg kommer en övergång till bygginformationsmodeller att ske (BIM) där informationen kommer att integreras mellan olika aktörer och skeenden i byggprocessen. En sådant naturligt steg är att integrera projektering och produktion där stora värden kan sparas om BIM modellen kan användas för inköp, planering och genomförandet i produktionsprocessen. En demonstrationsmiljö har byggts upp med en modellserver, en BIM Collaboration Hub, för att hantera IFC-filer som definierar byggnaden och andra filtyper som används i olika affärsprocesser. De olika bygg- och installationsdelarna kan läsas in med sina versioner från CAD-system i IFC-formatet och därefter knytas till annan information som t ex krav och tidplaneaktiviteter. Arkitekturen ger en flexibel lösning där företag kan samverka med hjälp av olika överföringsmetoder - filöverföring, tjänster som anropas och inmatning via ett grafiskt användargränssnitt. Den processmodell som utvecklats i inVBE projektet och som utgör viktig del i Håkan Norbergs lic-avhandling (se referenslistan) skapar bättre förutsättningar för beredning/koordinering, synkronisering, rapportering och uppföljning av produktionen på byggarbetsplatserna. Vid projektets slutpresentation var intresset stort från flera byggföretag att prova och utvärdera det nya arbetssättet och de nya verksamhetsstödjande applikationerna. Ambitionen är därför att tillsammans med intresserat byggföretag med lämpligt byggprojekt ansöka om SBUF medel för att genom fältprov utvärdera om förväntade kvalitets- och produktivitetsförbättringar erhålls i verkligheten.
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| 5. |
- Puttige, Anjan Rao, 1990-, et al.
(author)
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Method to estimate the ground loads for missing periods in a monitored GSHP
- 2019
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In: EUROPEAN GEOTHERMAL CONGRESS 2019.
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Conference paper (other academic/artistic)abstract
- Monitoring a ground source heat pump can provide important insights into its working, but to study the behaviour of the borehole heat exchanger (BHE) we require monitored data for the whole period of operation. In practice, the monitored data often has periods of missing data. We propose a method to estimate the load during the periods of missing data based on the fluid temperature after that period. The method determined the missing load with negligible error, for the case of a BHE that behaves exactly like the model describing it. A sensitivity analysis showed that the estimated load is highly sensitive to errors in measured load and fluid temperature. The method was applied to a real monitored BHE, the magnitude of estimated loads were unreasonably high, but the overall deviation between the measured and simulated values of fluid temperature decreased. Therefore, the high magnitude of missing load compensates for the lack of agreement between the model and the measured data.
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| 6. |
- Ramirez Villegas, Ricardo
(author)
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A methodology to assess impacts of energy efficient renovation : a Swedish case study
- 2017
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Licentiate thesis (other academic/artistic)abstract
- The European Union aims to reduce energy use and CO2-emissions by 40 % by the year 2030. The building sector has been identified as having a great potential to reduce emission of CO2 by increasing its energy efficiency. Also, there is a growing concern of the buildings environmental performance, that lead to the development of building environmental assessment tools. However, different types of energy sources and confusing environmental impacts affect the decision making when renovating for improved energy efficiency. This study develops and tests a methodology to help decision-makers when considering major renovation of their building stock when connected to adistrict heating system. The proposed methodology is applied and used to investigate how different renovation scenarios affects the building environmental impacts in terms of CO2 emissions and identify and discuss future improvements of the methodology.The novelty of the method is the expanded system boundaries that include both the distribution and production of district heating and the energy use at a building level. In this way it is possible to compare and weight measures made both at the energy system level and the building level. This work has limited its approach to energy use in buildings, but it is important to bring the life cycle thinking to the methodology. During the choice of the renovation methods it was noticed that the environmental impact of the production of some components in order to reduce the energy use of a building are not insignificant. Even if all the renovation measures considered in this case study are feasible, it is important to determine in which order they are desirable or achievable from an economic point of view. Uncertainty in the future development of energy, and limited economic resources can play an important role in the possibility of energy efficient renovation.
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| 7. |
- Ramirez Villegas, Ricardo, 1981-
(author)
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Energy efficient renovation in a life cycle perspective : A case study of a Swedish multifamily-building
- 2021
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Doctoral thesis (other academic/artistic)abstract
- Energy use in the European Union is increasing. At the same time, it is estimated that by the year 2050 most of the EU population will be living in currently existing buildings. Some of these buildings are or will be in need of renovation, and they have identified a target to reduce overall energy use. The urgency of climate change also makes it highly relevant and important to improve buildings resource and energy efficiency. This thesis aims to explain how different proposed energy efficient renovation strategies affect the energy use at different system levels, the potential environmental impacts of these alternatives, how they are connected to economic impacts and the implications of using a commercial LCA software to answer these questions from a research perspective.In order to answer the questions above, the effect of different renovation strategies were studied by combining building energy simulations, energy system simulations, a building environmental assessment tool, life cycle assessment and life cycle cost calculations. These tools are used in order to provide an overview of how the different renovation strategies affect the production of district heating, greenhouse gas (GHG) emissions and the environmental and economic performance of the building.The results show that the selected renovation strategies reduce energy use by decreasing transmission losses, while reducing the total amount of purchased energy by using solar energy or by changing energy carriers. These different approaches have the potential to reduce the environmental impact, mainly by reducing global warming potential, acidification potential and eutrophication potential and to some extent abiotic depletion potential. However, when changing energy carriers there is a burden shift to radioactive waste disposed. When the economic aspects are analyzed, it is shown that there is no simple correlation between financial and environmental impacts.To analyze a building from a life cycle perspective can help to identify the advantages and disadvantages of energy efficient renovation from the building owner’s perspective as well as from a societal perspective. Applying a life cycle perspective is therefore important for building owners, building companies and practitioners as well for policy makers to avoid suboptimisation.
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| 8. |
- Rusinowski, P., et al.
(author)
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Numerical analysis of two-way concrete slabs with openings strengthened with CFRP
- 2006
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In: Bridge maintenance, safety, management, life-cycle performance and cost. - London : Taylor & Francis Group. - 0415403154 - 9780415403153 ; , s. 1045-1046, s. 387-390
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Conference paper (other academic/artistic)abstract
- Carbon Fibre Reinforced Polymers, CFRP, offer excellent corrosion resistance to environmental agents as well as the advantages of high stiffness-to-weight and strength-to-weight ratios when compared to conventional construction materials. Perhaps the biggest advantage of CFRP is its tailorability. One common application for CFRP sheets is to strengthen slabs and walls when openings are to be made. In spite of this, there have not been many studies reported on slabs with openings strengthened with CFRP and especially, not with distributed loading. This paper presents numerical analyses of simply supported two-way concrete slabs with openings strengthened with CFRP sheets. The finite element program ABAQUS is utilized for the analyses. The analyses are compared with full-scale laboratory tests and show a good agreement
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| 9. |
- Saini, Puneet Kumar
(author)
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Solar integrated heating systems: Applications in buildings and industries
- 2023
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Doctoral thesis (other academic/artistic)abstract
- “Heat is half” of the global final energy consumption, and the decarbonization of the heating sector is critical to achieving climate goals. This thesis employs a system modelling approach to evaluate renewable heating systems. The overarching goal is to reduce fossil fuel reliance by integrating renewable energy technologies, such as solar thermal, photovoltaics, photovoltaic thermal, heat pump, and thermal energy storage in different system concepts. Two primary sectors are addressed: buildings, with a focus on utilizing solar collectors and heat pumps for heating systems in multifamily houses by recovery of waste heat; and industries, utilizing solar collectors for steam generation below 200 °C. The work is centred around five primary research questions, addressing the technical and economic feasibility of the mentioned technologies and their roles in decarbonization.Two system arrangements were simulated to address the heating demands of buildings: a) Centralized heat pump that utilizes ventilation air as a heat source, serving three multifamily buildings, and b) A fifth generation district heating system that utilizes industrial waste heat as its source. The techno-economic performance of these systems was evaluated. The results suggest that the economic viability of such arrangements largely depends on critical factors that include the costs of heat pump sub-stations, prevailing electricity prices, and the cost of waste heat. Incorporating solar air heating collectors and optimizing flow controls enhance both component and system energy efficiency. Moreover, integrating photovoltaic systems, up to a specific capacity, is advantageous as it offers reductions in heating costs.For industrial steam generation, the importance of the solar fraction in technological comparisons is highlighted. Parabolic trough collector and heat pump for steam generation are compared for 34 locations in the European Union, using solar fraction as an indicator. The results highlight the economic competitiveness of both technologies for a wide range of boundary conditions. However, heating costs from solar thermal collectors increase at higher solar fractions, primarily due to the storage costs. This trend sets an economic limit on the maximum feasible solar fraction. As a result, hybrid systems combining solar thermal collectors with steam heat pumps offer a promising combination to achieve a high renewable fraction for industrial applications.Concerns about CO2 emissions from the electricity grid, and its reliability in many countries, necessitate the exploration of alternative system concepts to meet a higher fraction of heating demand. One such novel energy system combines a parabolic trough collector, photovoltaic, and thermal energy storage (using water and sand as storage media) to reach a combined solar fraction of 90 %, while remaining cost-competitive with fossil fuels. The techno-economic performance of solar thermal collectors is system dependent, largely influenced by their integration within industrial systems. Two novel indicators are introduced to quantify the integration incompatibilities, offering insights into the dynamics for specific integration point. Using this method for a case study resulted in an optimized configuration, improving the overall system performance.Collectively, the results are expected to be leveraged by relevant stakeholders to advance the cause of heating decarbonization in buildings and industries.
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| 10. |
- Sandberg, Karin, et al.
(author)
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Hållbarhetsutvärdering av byggnader : Case Ripan i Kiruna
- 2018
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Reports (other academic/artistic)abstract
- Sustainability includes several parameters, and these can be measured and valued in many different ways. This study focuses on balancing the various parts to achieve sustainability by minimizing energy for heating and energy to produce the materials used in the building as well as minimizing cost for material investment and cost for heating using optimization techniques. This is balanced together with the environmental impact. This report describes an initial study for sustainability optimization of a smaller building. The goal is to develop a comprehensive approach to provide a broader basis of decisions for new construction.The calculation included the building envelope (exterior walls, roof and floors), interior walls and stabilizing elements for different frames of wood (timber frame and CLT).The result from the Ripan Case shows that the timber frame design has the lowest embodied energy and operating energy, and lowest cost for investment and heating during the operating phase. The environmental impact of the timber frame design was also low.
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