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Publications (10 of 32) Show all publications
Garman, I., Myhren, J. A. & Mattsson, M. (2025). Energy use of advanced ventilation systems in a cold climate single-family house. Energy and Buildings, 330, Article ID 115329.
Open this publication in new window or tab >>Energy use of advanced ventilation systems in a cold climate single-family house
2025 (English)In: Energy and Buildings, ISSN 0378-7788, E-ISSN 1872-6178, Vol. 330, article id 115329Article in journal (Refereed) Published
Abstract [en]

Warming up incoming fresh air can account for half the space heating demand of a well insulated residential building. Variable air supply (e.g. by demand control) and energy recovery with an air-to-air heat exchanger reduce that demand. However in real-world settings, expected cost and environmental impact savings may not arise, leading to a so-called performance gap. This long-term study followed the building occupancy and electricity consumption of a modern family home in central Sweden, heated using a ground-source heat pump. Over three winters, three mechanical ventilation systems were trialled. Two had heat recovery – flat-plate or rotating wheel – while one was an exhaust system equipped with sensors for demand control of individual rooms. Variable airflow by simple schedule was also evaluated. In consistently subzero temperature conditions, the rotating wheel offered energy savings of at least 11 % compared to the flat-plate device. There was however no evidence (within a warmer temperature range) of a clear difference in heat demand between the exhaust system trials and those with heat recovery. The timing of electrical demand periods suggested that this apparent heat recovery performance gap related to temperature regulation and frost protection within the air handling units. In this real-world setting, with a ground-source heat pump providing baseload warmth, heat recovery ventilation provided limited electrical energy savings, and appeared to align the timing of power demand peaks more closely with falling outdoor air temperature.

Keywords
Domestic ventilation, Heat recovery, Exhaust, Performance gap, Heat pump
National Category
Energy Engineering Building Technologies
Research subject
Research Centres, Sustainable Energy Research Centre (SERC)
Identifiers
urn:nbn:se:du-50092 (URN)10.1016/j.enbuild.2025.115329 (DOI)001409858900001 ()2-s2.0-85215826463 (Scopus ID)
Available from: 2025-01-30 Created: 2025-01-30 Last updated: 2025-02-10Bibliographically approved
Almusaed, A., Yitmen, I., Myhren, J. A. & Almssad, A. (2024). Assessing the Impact of Recycled Building Materials on Environmental Sustainability and Energy Efficiency: A Comprehensive Framework for Reducing Greenhouse Gas Emissions. Buildings, 14(6), Article ID 1566.
Open this publication in new window or tab >>Assessing the Impact of Recycled Building Materials on Environmental Sustainability and Energy Efficiency: A Comprehensive Framework for Reducing Greenhouse Gas Emissions
2024 (English)In: Buildings, E-ISSN 2075-5309, Vol. 14, no 6, article id 1566Article in journal (Refereed) Published
Abstract [en]

In this study, we critically examine the potential of recycled construction materials, focusing on how these materials can significantly reduce greenhouse gas (GHG) emissions and energy usage in the construction sector. By adopting an integrated approach that combines Life Cycle Assessment (LCA) and Material Flow Analysis (MFA) within the circular economy framework, we thoroughly examine the lifecycle environmental performance of these materials. Our findings reveal a promising future where incorporating recycled materials in construction can significantly lower GHG emissions and conserve energy. This underscores their crucial role in advancing sustainable construction practices. Moreover, our study emphasizes the need for robust regulatory frameworks and technological innovations to enhance the adoption of environmentally responsible practices. We encourage policymakers, industry stakeholders, and the academic community to collaborate and promote the adoption of a circular economy strategy in the building sector. Our research contributes to the ongoing discussion on sustainable construction, offering evidence-based insights that can inform future policies and initiatives to improve environmental stewardship in the construction industry. This study aligns with the European Union's objectives of achieving climate-neutral cities by 2030 and the United Nations' Sustainable Development Goals outlined for completion by 2030. Overall, this paper contributes to the ongoing dialogue on sustainable construction, providing a fact-driven basis for future policy and initiatives to enhance environmental stewardship in the industry.

Place, publisher, year, edition, pages
MDPI, 2024
Keywords
life cycle assessment, circular economy, greenhouse gas emissions, energy efficiency in construction, sustainable building materials
National Category
Construction Management
Identifiers
urn:nbn:se:du-49106 (URN)10.3390/buildings14061566 (DOI)001254401900001 ()2-s2.0-85196854827 (Scopus ID)
Available from: 2024-07-26 Created: 2024-07-26 Last updated: 2024-09-18Bibliographically approved
Almusaed, A., Yitmen, I., Almssad, A. & Myhren, J. A. (2024). Construction 5.0 and Sustainable Neuro-Responsive Habitats: Integrating the Brain–Computer Interface and Building Information Modeling in Smart Residential Spaces. Sustainability, 16(21), Article ID 9393.
Open this publication in new window or tab >>Construction 5.0 and Sustainable Neuro-Responsive Habitats: Integrating the Brain–Computer Interface and Building Information Modeling in Smart Residential Spaces
2024 (English)In: Sustainability, E-ISSN 2071-1050, Vol. 16, no 21, article id 9393Article in journal (Refereed) Published
Abstract [en]

This study takes a unique approach by investigating the integration of Brain–Computer Interfaces (BCIs) and Building Information Modeling (BIM) within residential architecture. It explores their combined potential to foster neuro-responsive, sustainable environments within the framework of Construction 5.0. The methodological approach involves real-time BCI data and subjective evaluations of occupants’ experiences to elucidate cognitive and emotional states. These data inform BIM-driven alterations that facilitate adaptable, customized, and sustainability-oriented architectural solutions. The results highlight the ability of BCI–BIM integration to create dynamic, occupant-responsive environments that enhance well-being, promote energy efficiency, and minimize environmental impact. The primary contribution of this work is the demonstration of the viability of neuro-responsive architecture, wherein cognitive input from Brain–Computer Interfaces enables real-time modifications to architectural designs. This technique enhances built environments’ flexibility and user-centered quality by integrating occupant preferences and mental states into the design process. Furthermore, integrating BCI and BIM technologies has significant implications for advancing sustainability and facilitating the design of energy-efficient and ecologically responsible residential areas. The study offers practical insights for architects, engineers, and construction professionals, providing a method for implementing BCI–BIM systems to enhance user experience and promote sustainable design practices. The research examines ethical issues concerning privacy, data security, and informed permission, ensuring these technologies adhere to moral and legal requirements. The study underscores the transformational potential of BCI–BIM integration while acknowledging challenges related to data interoperability, integrity, and scalability. As a result, ongoing innovation and rigorous ethical supervision are crucial for effectively implementing these technologies. The findings provide practical insights for architects, engineers, and industry professionals, offering a roadmap for developing intelligent and ethically sound design practices. © 2024 by the authors.

Place, publisher, year, edition, pages
Multidisciplinary Digital Publishing Institute (MDPI), 2024
Keywords
brain–computer interface (BCI), building information modeling (BIM), neuro-responsive design, smart residential spaces, sustainable architecture, brain, design, numerical model, sustainability
National Category
Civil Engineering
Identifiers
urn:nbn:se:du-49758 (URN)10.3390/su16219393 (DOI)2-s2.0-85208577575 (Scopus ID)
Available from: 2024-11-29 Created: 2024-11-29 Last updated: 2024-11-29Bibliographically approved
Khadra, A., Akander, J. & Myhren, J. A. (2024). Greenhouse Gas Payback Time of Different HVAC Systems in the Renovation of Nordic District-Heated Multifamily Buildings Considering Future Energy Production Scenarios. Buildings, 14(2), 1-17, Article ID 413.
Open this publication in new window or tab >>Greenhouse Gas Payback Time of Different HVAC Systems in the Renovation of Nordic District-Heated Multifamily Buildings Considering Future Energy Production Scenarios
2024 (English)In: Buildings, E-ISSN 2075-5309, Vol. 14, no 2, p. 1-17, article id 413Article in journal (Refereed) Published
Abstract [en]

The European Union (EU) has implemented several policies to enhance energy efficiency. Among these policies is the objective of achieving energy-efficient renovations in at least 3% of EU buildings annually. The primary aim of this study was to offer a precise environmental comparison among four similar district-heated multifamily buildings that have undergone identical energy efficiency measures. The key distinguishing factor among them lies in the HVAC systems installed. The chosen systems were as follows: (1) exhaust ventilation with air pressure control; (2) mechanical ventilation with heat recovery; (3) exhaust ventilation with an exhaust air heat pump; and (4) exhaust ventilation with an exhaust air heat pump with a Photovoltaic (PV) panel. This study involved a life cycle assessment that relied on actual material data from the housing company and energy consumption measurements. This study covered a period of 50 years for thorough analysis. A sensitivity analysis was also conducted to account for various future scenarios of energy production. The findings revealed that the building with an exhaust air heat pump exhibited the lowest greenhouse gas emissions and the shortest carbon payback period (GBPT), needing only around 7 years. In contrast, the building with exhaust ventilation without heat recovery showed the highest emissions and the longest carbon payback period (GBPT), requiring approximately 11 years. Notably, the results were significantly influenced by future scenarios of energy production, emphasizing the crucial role of emission factors in determining the environmental performance of distinct renovation scenarios.

Place, publisher, year, edition, pages
MDPI, 2024
Keywords
life cycle assessment; carbon payback time; multifamily buildings; renovation; HVAC systems; future energy production scenarios
National Category
Building Technologies
Identifiers
urn:nbn:se:du-48015 (URN)10.3390/buildings14020413 (DOI)001172082700001 ()2-s2.0-85185710424 (Scopus ID)
Funder
Swedish Energy Agency, 40811-2
Available from: 2024-02-12 Created: 2024-02-12 Last updated: 2024-06-14
Garman, I., Mattsson, M., Myhren, J. A. & Persson, T. (2023). Demand control and constant flow ventilation compared in an exhaust ventilated bedroom in a cold-climate single-family house. Intelligent Buildings International, 15(4), 175-188
Open this publication in new window or tab >>Demand control and constant flow ventilation compared in an exhaust ventilated bedroom in a cold-climate single-family house
2023 (English)In: Intelligent Buildings International, ISSN 1750-8975, E-ISSN 1756-6932, Vol. 15, no 4, p. 175-188Article in journal (Refereed) Published
Abstract [en]

A convertible, zoned ventilation system was field-tested in a modern, airtight Swedish home when occupied either by an experimental team or by a family. Indoor air quality in the master bedroom was monitored under four ventilation strategies. Relative to constant air volume strategies (CAV), demand-controlled ventilation (DCV) that was responding to CO2 concentration extracted more air when people were present, but less in total over 24 h. This elevated the indoor air humidity, beneficial in climates with dry winter air. Multiple monitors within the bedroom indicated that vertical CO2 stratification occurred routinely, presumably due to low mixing of supply air from a wall-mounted diffuse vent, spreading the air radially over the wall. This seemingly improved air quality in the breathing zone under local (ceiling) extract ventilation but worsened it during more typical, centralised extract ventilation, where air escapes the room via an inner doorway. The local extract arrangement thus seemed to yield both improved ventilation efficiency and reduced contaminant spread to other rooms. The noted air quality variations within the room highlight the importance of sensor placement in demand-control ventilated spaces, even in small rooms such as bedrooms.

Keywords
Indoor environmental quality, ventilation, occupant comfort, intelligent building, digital homes
National Category
Building Technologies
Identifiers
urn:nbn:se:du-46781 (URN)10.1080/17508975.2023.2236993 (DOI)001046568500001 ()
Available from: 2023-08-25 Created: 2023-08-25 Last updated: 2024-03-26Bibliographically approved
Shen, J., Boyle, P. & Myhren, J. A. (2022). Offerings and challenges of demand response ventilation under covid-19 scenarios. In: Proceedings of the 17th IBPSA Conference Bruges, Belgium, Sept. 1-3, 2021: . Paper presented at 17th IBPSA Conference Bruges, Belgium, Sept. 1-3, 2021 (pp. 2368-2373). International Building Performance Simulation Association
Open this publication in new window or tab >>Offerings and challenges of demand response ventilation under covid-19 scenarios
2022 (English)In: Proceedings of the 17th IBPSA Conference Bruges, Belgium, Sept. 1-3, 2021, International Building Performance Simulation Association , 2022, p. 2368-2373Conference paper, Oral presentation with published abstract (Refereed)
Abstract [en]

Owning to the outbreak of COVID-19, individuals have to spend more time indoor. It is therefore essential to prepare for a long-term healthy indoor working environment in the transition of post COVID-19 pandemic. However, there is no relevant research so far in investigating such crisis impacts around indoor environmental quality and economic-health issues while home offices are expected becoming common practice soon. Therefore, a case of single-family house in Sweden is specially investigated using IDA ICE. By comparing four predominant ventilation approaches, three operational schedules are proposed, covering different confinement for occupants. Main results show that the demand response ventilation (DRV) generally should sacrifice in remarkable performance in energy saving, and emission reduction to better confront with more challenges in indoor air quality, occupied thermal dissatisfaction fraction and air stagnation under the challenge of COVID-19 pandemic scenario. Altered ventilation strategy should be customized from increased outdoor air supply, various demand-control signal, displacement method towards a heathier homeworking environment. © International Building Performance Simulation Association, 2022

Place, publisher, year, edition, pages
International Building Performance Simulation Association, 2022
Keywords
Air quality, COVID-19, Emission control, Energy conservation, Indoor air pollution, Demand response, Energy-saving and emission reductions, Environmental economics, Health issues, Home office, Indoor air quality, Indoor environmental quality, Performance, Single-family house, Working environment, Ventilation
National Category
Building Technologies
Identifiers
urn:nbn:se:du-45875 (URN)10.26868/25222708.2021.30129 (DOI)2-s2.0-85151541309 (Scopus ID)9781775052029 (ISBN)
Conference
17th IBPSA Conference Bruges, Belgium, Sept. 1-3, 2021
Available from: 2023-04-21 Created: 2023-04-21 Last updated: 2023-04-21Bibliographically approved
Khadra, A., Hugosson, M., Akander, J. & Myhren, J. A. (2020). Development of a weight factor method for sustainability decisions in building renovation. Case study using renobuild. Sustainability (Switzerland), 12(17), Article ID 7194.
Open this publication in new window or tab >>Development of a weight factor method for sustainability decisions in building renovation. Case study using renobuild
2020 (English)In: Sustainability (Switzerland), E-ISSN 2071-1050, Vol. 12, no 17, article id 7194Article in journal (Refereed) Published
Place, publisher, year, edition, pages
MDPI, 2020
National Category
Civil Engineering
Research subject
Research Profiles 2009-2020, Energy and Built Environments
Identifiers
urn:nbn:se:du-34997 (URN)10.3390/su12177194 (DOI)000570340400001 ()2-s2.0-85090425408 (Scopus ID)
Available from: 2020-09-15 Created: 2020-09-15 Last updated: 2021-11-12Bibliographically approved
Khadra, A., Hugosson, M., Akander, J. & Myhren, J. A. (2020). Economic performance assessment of three renovated multi-family buildings with different HVAC systems. Energy and Buildings, 224, Article ID 110275.
Open this publication in new window or tab >>Economic performance assessment of three renovated multi-family buildings with different HVAC systems
2020 (English)In: Energy and Buildings, ISSN 0378-7788, E-ISSN 1872-6178, Vol. 224, article id 110275Article in journal (Refereed) Published
National Category
Civil Engineering
Research subject
Research Profiles 2009-2020, Energy and Built Environments
Identifiers
urn:nbn:se:du-34646 (URN)10.1016/j.enbuild.2020.110275 (DOI)000571218200010 ()2-s2.0-85087899249 (Scopus ID)
Available from: 2020-08-04 Created: 2020-08-04 Last updated: 2021-11-12Bibliographically approved
Myhren, J. A., Heier, J., Hugosson, M. & Zhang, X. (2020). The perception of Swedish housing owner’s on the strategies to increase the rate of energy efficient refurbishment of multi-family buildings. Intelligent Buildings International, 12(3), 153-168
Open this publication in new window or tab >>The perception of Swedish housing owner’s on the strategies to increase the rate of energy efficient refurbishment of multi-family buildings
2020 (English)In: Intelligent Buildings International, ISSN 1750-8975, E-ISSN 1756-6932, Vol. 12, no 3, p. 153-168Article in journal (Refereed) Published
Abstract [en]

Improving the energy performance of existing buildings is crucial for reaching both EU and national climate and energy targets. The main objective of this study was to map challenges that Swedish housing owners perceive when making energy-efficiency refurbishments. A secondary objective was to compare how well these challenges relate to national strategies. The study applied a combined methods approach with audience response meters and in-depth qualitative semi-structured interviews. The housing owners express the view that they have sufficient knowledge of national ambitions to improve the energy performance of buildings and welcome the new building regulations. Despite this supposed knowledge and the current economic situation with beneficial loans, the refurbishment rate still remains low. The housing owners explain that they are concerned about the ‘performance gap’ and request more accurate energy performance predictions. They are also waiting for proof that all sustainability goals can be reached in reality. Probably, too few projects fulfilling ambitions in all categories: economically, socially and energy-wise have been followed up and demonstrated nationally. The new national information centre on refurbishment of buildings may help to spread information about such projects, raise awareness and thus increase the refurbishment rate.

Keywords
Energy conservation measures, facilities management, stakeholders, sustainable development
National Category
Energy Engineering
Research subject
Research Profiles 2009-2020, Energy and Built Environments
Identifiers
urn:nbn:se:du-29244 (URN)10.1080/17508975.2018.1539390 (DOI)000563707400002 ()2-s2.0-85059056313 (Scopus ID)
Available from: 2019-01-03 Created: 2019-01-03 Last updated: 2021-11-12Bibliographically approved
Petrovic, B., Myhren, J. A., Zhang, X., Wallhagen, M. & Eriksson, O. (2019). Life cycle assessment of a wooden single-family house in Sweden. Applied Energy, 251, 113-253, Article ID 113253.
Open this publication in new window or tab >>Life cycle assessment of a wooden single-family house in Sweden
Show others...
2019 (English)In: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 251, p. 113-253, article id 113253Article in journal (Refereed) Published
Abstract [en]

To understand the reasons behind the large environmental impact from buildings the whole life cycle needs to be considered. Therefore, this study evaluates the carbon dioxide emissions in all stages of a single-family house in Sweden from the production of building materials, followed by construction and user stages until the end-of-life of the building in a life cycle assessment (LCA). The methodology applied is attributional life cycle assessment (LCA) based on ‘One Click LCA’ tool and a calculated life span of 100 years. Global warming potential (GWP) and primary energy (PE) are calculated by using specific data from the case study, furthermore the data regarding building materials are based on Environmental Product Declarations (EPDs). The results show that the selection of wood-based materials has a significantly lower impact on the carbon dioxide emissions in comparison with non-wood based materials. The total emissions for this single-family house in Sweden are 6 kg CO 2 e/m 2 /year. The production stage of building materials, including building systems and installations represent 30% of the total carbon dioxide equivalent emissions, while the maintenance and replacement part represents 37%. However, energy use during the in-use stage of the house recorded lower environmental impact (21%) due to the Swedish electricity mix that is mostly based on energy sources with low carbon dioxide emissions. The water consumption, construction and the end-of-life stages have shown minor contribution to the buildings total greenhouse gas (GHG) emissions (12%). The primary energy indicator shows the largest share in the operational phase of the house.

Keywords
Carbon dioxide equivalent emission, Environmental product declaration, Global warming potential, Life cycle assessment, Primary energy, Single-family house
National Category
Energy Systems
Research subject
Research Profiles 2009-2020, Energy and Built Environments
Identifiers
urn:nbn:se:du-30118 (URN)10.1016/j.apenergy.2019.05.056 (DOI)000497966300013 ()2-s2.0-85065788114 (Scopus ID)
Available from: 2019-05-31 Created: 2019-05-31 Last updated: 2024-06-17Bibliographically approved
Organisations
Identifiers
ORCID iD: ORCID iD iconorcid.org/0000-0002-9943-9878

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