1.
Shadram, Farshid, 1987-
(författare)
Assessment and optimization of life cycle enrgy use in buildings
2018
Doktorsavhandling (övrigt vetenskapligt/konstnärligt) abstract
Buildings account for 40% of all energy use in European countries. The European Union (EU) therefore encourages member states to adopt Energy Efficiency Measures (EEMs) and implement energy-efficient practices during building design to minimize the energy use of buildings. However, recent studies have shown that energy-efficient buildings may not always outperform conventional buildings in terms of Life Cycle Energy (LCE) use. This is mainly due to the trade-off between embodied and operational energy, and a reliance on EEMs that reduce operational energy while sometimes increasing embodied energy and LCE use. To improve buildings’ environmental performance, the impact of different EEMs on buildings’ energy use needs to be assessed from a lifecycle perspective, and methods for identifying optimal combinations of EEMs that minimize LCE use should be developed. Ideally, these methods should be integrated with building information modelling (BIM) to enable seamless data exchange and to help Architecture, Engineering and Construction (AEC) practitioners make optimal design decisions relating to EEMs. The work presented in this thesis had two overall objectives: (1) to explore the scope for developing BIM-supported method(s) for assessing and optimizing the impact of EEMs on buildings’ LCE use during the design process, and (2) use the BIM-supported method(s) for exploring the impact of various EEMs that are implemented and modified during the building design process on the buildings’ LCE use.The work presented in this thesis is based on an exploratory research design involving iterative cycles of (1) problem identification, (2) method development, (3) method examination, and (4) theory suggestion. In step 1, problems were identified by conducting literature studies and workshops with AEC practitioners, and analyzing archival data. In step 2, prototyping was used to develop methods to overcome the identified problems. In step 3, the applicability of these methods (or prototypes) was tested in case studies on actual and hypothetical building projects. Three case studies were conducted – one dealing with a low energy dwelling located in Kiruna, Sweden; another dealing with a multifamily residential building in Uppsala, Sweden; and a third dealing with a hypothetical multifamily residential building in Stockholm, Sweden. In step 4, the results were compared to existing theories to strengthen existing knowledge and identify previously unrecognized findings.In relation to the first objective, the results obtained show that the factors and activities required to develop BIM-supported method(s) for assessing and optimizing the impact of EEMs on a building’s LCE use during the design phase are:• A database that stores external and building project data (e.g. BIM data) and links it to be used for assessment and optimization, providing access to the data whenever needed.• The development of interfaces using middleware applications to ensure interoperability and seamless automated exchange of information between BIM and other systems.• Predefined objects (i.e. building part and component recipes) that are stored in a database and linked to inventories and Environmental Product Declarations (EPDs) for the relevant materials, enabling assessment of the buildings’ embodied energy and LCE use.• The application of multi-objective optimization techniques (e.g. Pareto-based genetic algorithms) to identify optimal solution(s) for EEMs that minimize (optimize) the building’s LCE use.In relation to the second objective of the thesis, the results obtained indicate that:• EEMs that are implemented and modified during the detailed design phase have much less influence on the building’s LCE use than those implemented in the early design phase. Highly influential EEMs related to the early design phase which were tested herein were the building’s shape, orientation, Window to Wall Ratio (WWR), and the selection of materials used in the building envelope.• Generally, thickening roof insulation has a strong beneficial effect on LCE use for buildings in Sweden.• For buildings using energy sources with high primary energy factors, the most effective way to reduce LCE use may be to implement many EEMs that reduce operational energy use. However, this approach may be less helpful for buildings using greener energy sources because in such cases the embodied energy may have a greater effect on the final LCE use.• The embodied energies of materials in the same class can vary significantly between suppliers. Such differences in embodied energy can be identified by considering the suppliers’ EPDs, the energetic contributions due to their mode of transportation from the site of production, and the distance between the site of production and the construction site.• If the developed optimization approach is used to identify optimal combinations of EEMs in the early design phase, designers can freely choose from a wide range of building shapes without greatly affecting LCE use. However, without early phase optimization, designs that use different building shapes may exhibit significantly different LCE use values.The results provide both theoretical and practical contributions that may be useful to researchers and AEC practitioners seeking to develop BIM-supported design processes and to reduce buildings’ LCE use by adopting appropriate EEMs. The results also show that embodied energy can be a major component of a building’s LCE use if the building’s design relies heavily on EEMs designed solely to reduce operational energy use. Policy makers and governmental bodies are thus advised to update regulations and building codes to reflect the importance of embodied energy so as to minimize the LCE use of new and retrofitting building projects.
2.
Jansson, Gustav, et al.
(författare)
Requirements transformation in construction design
2010
Ingår i: CIB W78 27th International Conference on Applications of IT in the AEC Industry & Accelerating BIM Research Workshop.
Konferensbidrag (övrigt vetenskapligt/konstnärligt) 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.
3.
Ramirez Villegas, Ricardo, et al.
(författare)
Life Cycle Assessment of Building Renovation Measures : Trade-off between Building Materials and Energy
2019
Ingår i: Energies. - : MDPI. - 1996-1073. ; 12:3
Tidskriftsartikel (refereegranskat) abstract
The scope of this study is to assess how different energy efficient renovation strategies affect the environmental impacts of a multi-family house in a Nordic climate within district heating systems. The European Union has set ambitious targets to reduce energy use and greenhouse gas emissions by the year 2030. There is special attention on reducing the life cycle emissions in the buildings sector. However, the focus has often been on new buildings, although existing buildings represent great potential within the building stock in Europe. In this study, four different renovation scenarios were analyzed with the commercially available life cycle assessment software that follows the European Committee for Standardization (CEN) standard. This study covers all life cycle steps from the cradle to the grave for a residential building in Borlange, Sweden, where renewable energy dominates. The four scenarios included reduced indoor temperature, improved thermal properties of building material components and heat recovery for the ventilation system. One finding is that changing installations gives an environmental impact comparable to renovations that include both ventilation and building facilities. In addition, the life cycle steps that have the greatest environmental impact in all scenarios are the operational energy use and the building and installation processes. Renovation measures had a major impact on energy use due to the cold climate and low solar irradiation in the heating season. An interesting aspect, however, is that the building materials and the construction processes gave a significant amount of environmental impact.
4.
Anund Vogel, Jonas, et al.
(författare)
Enbart avstånd och handhygien räcker inte
2023
Ingår i: Fastighetstidningen. - 0348-5552.
Tidskriftsartikel (populärvet., debatt m.m.) abstract
I denna debattartikel lyfter sex forskare frågan att myndigheter och branschorganisationer delvis gav olika råd kring åtgärder för att begränsa risken för smittspridning inomhus. För att klara nästa pandemi krävs bättre samordning av riktlinjer kring ventilation och luftkvalitet.
5.
Jassim, Hassanean, 1978-, et al.
(författare)
Determining the environmental impact of material hauling with wheel loaders during earthmoving operations
2019
Ingår i: Journal of the Air and Waste Management Association. - : Taylor & Francis. - 1096-2247 .- 2162-2906. ; 69:10, s. 1195-1214
Tidskriftsartikel (refereegranskat) abstract
A method has been developed to estimate the environmental impact of wheel loaders used in earthmoving operations. The impact is evaluated in terms of energy use and emissions of air pollutants (CO2, CO, NOx, CH4, VOC, and PM) based on the fuel consumption per cubic meter of hauled material. In addition, the effects of selected operational factors on emissions during earthmoving activities were investigated to provide better guidance for practitioners during the early planning stage of construction projects. The relationships between six independent parameters relating to wheel loaders and jobsite conditions (namely loader utilization rates, loading time, bucket payload, horsepower, load factor, and server capacity) were analyzed using artificial neural networks, machine performance data from manufacturer’s handbooks, and discrete event simulations of selected earthmoving scenarios. A sensitivity analysis showed that the load factor is the largest contributor to air pollutant emissions, and that the best way to minimize environmental impact is to maximize the wheel loaders’ effective utilization rates. The new method will enable planners and contractors to accurately assess the environmental impact of wheel loaders and/or hauling activities during earthmoving operations in the early stages of construction projects.Implications: There is an urgent need for effective ways of benchmarking and mitigating emissions due to construction operations, and particularly those due to construction equipment, during the pre-construction phase of construction projects. Artificial Neural Networks (ANN) are shown to be powerful tools for analyzing the complex relationships that determine the environmental impact of construction operations and for developing simple models that can be used in the early stages of project planning to select machine configurations and work plans that minimize emissions and energy consumption. Using such a model, it is shown that the fuel consumption and emissions of wheel loaders are primarily determined by their engine load, utilization rate, and bucket payload. Moreover, project planners can minimize the environmental impact of wheel loader operations by selecting work plans and equipment configurations that minimize wheel loaders’ idle time and avoid bucket payloads that exceed the upper limits specified by the equipment manufacturer.
6.
Norberg, Håkan, et al.
(författare)
Byggsynkronisering
2009
Rapport (övrigt vetenskapligt/konstnärligt) 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.
7.
Anund Vogel, Jonas, et al.
(författare)
Buildings post corona
2023
Ingår i: The REHVA European HVAC Journal. - 1307-3729. ; 59:2, s. 19-21
Tidskriftsartikel (populärvet., debatt m.m.) abstract
Buildings Post Corona is a Swedish collaborative research project between Chalmers, KTH Royal Institute of Technology, Lund, and Umeå Universities. The project supports the building sector in designing and maintaining sustainable buildings with a healthy and good indoor environment. The COVID-19 crisis has stressed the importance and urge of this research.The scope of the project is to develop a methodology for the operation and design of buildings with an indoor environment that meets future health and climate challenges. The project’s overall goal is to establish an interdisciplinary platform to document existing experiences and knowledge and to gain new knowledge required for good building design and operation.
8.
Cheng, Xiaogang, et al.
(författare)
A total bounded variation approach to low visibility estimation on expressways
2018
Ingår i: Sensors. - : MDPI. - 1424-8220. ; 18:2
Tidskriftsartikel (refereegranskat) abstract
Low visibility on expressways caused by heavy fog and haze is a main reason for traffic accidents. Real-time estimation of atmospheric visibility is an effective way to reduce traffic accident rates. With the development of computer technology, estimating atmospheric visibility via computer vision becomes a research focus. However, the estimation accuracy should be enhanced since fog and haze are complex and time-varying. In this paper, a total bounded variation (TBV) approach to estimate low visibility (less than 300 m) is introduced. Surveillance images of fog and haze are processed as blurred images (pseudo-blurred images), while the surveillance images at selected road points on sunny days are handled as clear images, when considering fog and haze as noise superimposed on the clear images. By combining image spectrum and TBV, the features of foggy and hazy images can be extracted. The extraction results are compared with features of images on sunny days. Firstly, the low visibility surveillance images can be filtered out according to spectrum features of foggy and hazy images. For foggy and hazy images with visibility less than 300 m, the high-frequency coefficient ratio of Fourier (discrete cosine) transform is less than 20%, while the low-frequency coefficient ratio is between 100% and 120%. Secondly, the relationship between TBV and real visibility is established based on machine learning and piecewise stationary time series analysis. The established piecewise function can be used for visibility estimation. Finally, the visibility estimation approach proposed is validated based on real surveillance video data. The validation results are compared with the results of image contrast model. Besides, the big video data are collected from the Tongqi expressway, Jiangsu, China. A total of 1,782,000 frames were used and the relative errors of the approach proposed are less than 10%.
9.
Nair, Gireesh, et al.
(författare)
Perspectives of building professionals on the use of LCA tools in Swedish climate declaration
2021
Ingår i: E3S Web of Conferences. - : EDP Sciences.
Konferensbidrag (refereegranskat) abstract
From 1st January 2022, Swedish government plan to introduce the climate declarations as a legal requirement for new buildings. LCA is a method that could be used to quantify buildings' climate impact. The climate declaration in the Swedish building code expects to create interest in LCA among stakeholders. This study aims to identify and understand the challenges and opportunities of using LCA by stakeholders during the early stage of construction process. The study is based on responses from six building professionals to a questionnaire. The policy implications of the study findings are discussed.
10.
Nydahl, Helena, 1990-, et al.
(författare)
Including future climate induced cost when assessing building refurbishment performance
2019
Ingår i: Energy and Buildings. - : Elsevier. - 0378-7788 .- 1872-6178. ; 203
Tidskriftsartikel (refereegranskat) abstract
Improving energy efficiency in the existing buildings stock is essential to limit climate change and the economic assessment of measures are traditionally only based on the reduction of energy costs: However, future financial benefits of limiting climate change are rarely included in the evaluation of refurbishment investments. Although, the costs associated with global warming are expected to be extensive. This study introduces a method for the financial evaluation of energy efficiency investments that merge the reduction of life cycle energy costs with the reduction of future climate induced costs. A case study is used to exemplify the method. The case study shows that when reduced future costs due to mitigated life cycle greenhouse gas emissions are included in the analysis, the ranking between different measures can change and traditionally non-profitable measures may become financially sound investments. The introduced Economy+ indicator is shown to be an accessible performance measure to assess building refurbishment and may also be used in the design stage of new construction. (C) 2019 The Authors. Published by Elsevier B.V.
