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Bäcklund, K., Lundqvist, P. & Molinari, M. (2024). Showcasing a Digital Twin for Higher Educational Buildings: Developing the Concept Towards Human Centricity. Frontiers in Built Environment, 10, Article ID 1347451.
Open this publication in new window or tab >>Showcasing a Digital Twin for Higher Educational Buildings: Developing the Concept Towards Human Centricity
2024 (English)In: Frontiers in Built Environment, E-ISSN 2297-3362, Vol. 10, article id 1347451Article in journal (Refereed) Published
Abstract [en]

Digital twin technology is an emerging technology within the built environment. There are yet many unexplored opportunities to utilize digital twins for facilitating the transformation towards a climate neutral building stock while also meeting the expectations from the building occupants. This article presents a case study of a digital twin, developed for an existing commercial building stock of campus areas in Sweden. The overarching purpose of the digital twin is to support both building occupants and building operators. This twofold human-centric approach represents a novel approach for building digital twins. The digital twin is based on 3D scanning and together with geospatial data, a real-like navigational indoor environment is created. Three innovative features are presented; the building analysis module, the digital twin mobile application and the building operations module. The results show that the digital twin improves the building occupant’s experience by supporting navigation and providing access to room booking system via this dedicated interface. Building management is also benefited by the digital twin through easier access to building data aggregated into one platform and a state-of-the-art analysis tool for optimizing the use of indoor space. The digital twin holds future potential to achieve operational excellence by incorporating feedback mechanisms and utilizing Artificial Intelligence to enable intelligent fault detection and prevention.

  Keywords: 

Place, publisher, year, edition, pages
Frontiers Media SA, 2024
Keywords
Digital Twin, Human-centric, Higher educational buildings, building occupants, Building operators, Sustaina
National Category
Architectural Engineering Social Sciences Building Technologies
Identifiers
urn:nbn:se:kth:diva-343531 (URN)10.3389/fbuil.2024.1347451 (DOI)001175692200001 ()2-s2.0-85186412533 (Scopus ID)
Projects
Cost- and Energy-Efficient Control Systems for Buildings
Funder
Swedish Energy Agency, 47859-1
Note

QC 20240313

Available from: 2024-02-15 Created: 2024-02-15 Last updated: 2024-04-24Bibliographically approved
Bäcklund, K., Molinari, M., Lundqvist, P. & Palm, B. (2023). Building Occupants, Their Behavior and the Resulting Impact on Energy Use in Campus Buildings: A Literature Review with Focus on Smart Building Systems. Energies, 16(17), 6104-6104
Open this publication in new window or tab >>Building Occupants, Their Behavior and the Resulting Impact on Energy Use in Campus Buildings: A Literature Review with Focus on Smart Building Systems
2023 (English)In: Energies, E-ISSN 1996-1073, Vol. 16, no 17, p. 6104-6104Article in journal (Refereed) Published
Abstract [en]

In the light of global climate change and the current energy crisis, it is crucial to target sustainable energy use in all sectors. Buildings still remain one of the most energy-demanding sectors. Campus buildings and higher educational buildings are important to target due to their high and increasing energy demand. This building segment also represents a research gap, as mostly office or domestic buildings have been studied previously. In the quest for thermal comfort, a key stakeholder in building energy demand is the building occupant. It is therefore crucial to promote energy-aware behaviors. The building systems are another key factor to consider. As conventional building systems are replaced with smart building systems, the entire scenario is redrawn for how building occupants interact with the building and its systems. This study argues that behavior is evolving with the smartness of building systems. By means of a semi-systematic literature review, this study presents key findings from peer-reviewed research that deal with building occupant behavior, building systems and energy use in campus buildings. The literature review was an iterative process based on six predefined research questions. Two key results are presented: a graph of reported energy-saving potentials and a conceptual framework to evaluate building occupants impact on building energy use. Furthermore, based on the identified research gaps in the selected literature, areas for future research are proposed.

Place, publisher, year, edition, pages
MDPI AG, 2023
Keywords
behavior; energy use; campus buildings; building occupants; smart building systems; educational buildings
National Category
Building Technologies
Research subject
Energy Technology
Identifiers
urn:nbn:se:kth:diva-344411 (URN)10.3390/en16176104 (DOI)001070065200001 ()2-s2.0-85170534245 (Scopus ID)
Funder
Swedish Energy Agency, 2018-016237
Note

QC 20240315

Available from: 2024-03-15 Created: 2024-03-15 Last updated: 2024-03-15Bibliographically approved
Bäcklund, K., Molinari, M. & Lundqvist, P. (2023). In Search for Untapped Energy-Saving Potential in Green and Smart Higher Educational Buildings—An Empirical Case Study Involving the Building Occupants. Buildings, 13(12), Article ID 3103.
Open this publication in new window or tab >>In Search for Untapped Energy-Saving Potential in Green and Smart Higher Educational Buildings—An Empirical Case Study Involving the Building Occupants
2023 (English)In: Buildings, E-ISSN 2075-5309, Vol. 13, no 12, article id 3103Article in journal (Refereed) Published
Abstract [en]

Energy-intense activities and the unpredictable and complex behavior of building occupants lead to an increase in building energy demand. It is, therefore, crucial to study underlying factors for building energy demand related to the users. Higher educational buildings are relevant to study for several reasons: they host the future workforce and citizens, they are predicted to increase in numbers, and they represent a building type less studied. Furthermore, green-rated buildings equipped with smart building systems also represent a research gap that is relevant to address since such a building design involves IoT-functionalities and digital features for the building occupants to interact with. There is also a conceivable risk that if the users know that the building is green-rated and technologically advanced, this may alter their perception of the building operation and thus their behavior. To study the relationship between building occupants and such green and smart educational structure, a survey was conducted in a Swedish higher educational building; as a result, 300 responses were collected and analyzed. The responses revealed that the building occupants act with energy awareness, and they are conscious about energy-saving behaviors. One building feature in particular was studied: the Digital Room Panels (DRPs). The DRP allows the building occupants to modify the indoor temperature and is, therefore, essential for thermal comfort. One key finding from the survey revealed that 70% of the building occupants did not know how the DRPs operate. This study argues that this result can be explained with a lack of communication and user friendliness. Inadequate interactions with building systems could also result in opportunities for energy saving might not be realized. The findings of this case study led to valuable recommendations and suggestions for future research endeavors.

Place, publisher, year, edition, pages
MDPI AG, 2023
Keywords
commercial buildings; campus; energy use; building occupants; behavior; energy awareness; green-rated buildings; smart building systems; indoor environmental quality
National Category
Building Technologies
Research subject
Energy Technology
Identifiers
urn:nbn:se:kth:diva-344412 (URN)10.3390/buildings13123103 (DOI)001130606300001 ()2-s2.0-85180648407 (Scopus ID)
Funder
Swedish Energy Agency, 2018-016237Swedish Foundation for Strategic Research, RIT17-0046
Note

QC 20240315

Available from: 2024-03-15 Created: 2024-03-15 Last updated: 2024-03-15Bibliographically approved
Farjadnia, M., Alanwar, A., Niazi, M. U., Molinari, M. & Johansson, K. H. (2023). Robust Data-Driven Predictive Control of Unknown Nonlinear Systems Using Reachability Analysis. In: : . Paper presented at European Control Conference 2023, 13 - 16 June, 2023, Bucharest, Romania.
Open this publication in new window or tab >>Robust Data-Driven Predictive Control of Unknown Nonlinear Systems Using Reachability Analysis
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2023 (English)Conference paper, Oral presentation with published abstract (Refereed)
Abstract [en]

This work proposes a robust data-driven predictive control approach for unknown nonlinear systems in the presence of bounded process and measurement noise. Data-driven reachable sets are employed for the controller design instead of using an explicit nonlinear system model. Although the process and measurement noise are bounded, the statistical properties of the noise are not required to be known. By using the past noisy input-output data in the learning phase, we propose a novel method to over-approximate reachable sets of an unknown nonlinear system. Then, we propose a data-driven predictive control approach to compute safe and robust control policies from noisy online data. The constraints are guaranteed in the control phase with robust safety margins through the effective use of the predicted output reachable set obtained in the learning phase. Finally, a numerical example validates the efficacy of the proposed approach and demonstrates comparable performance with a model-based predictive control approach.

Keywords
Predictive control for nonlinear systems, Robust control
National Category
Control Engineering
Identifiers
urn:nbn:se:kth:diva-336528 (URN)
Conference
European Control Conference 2023, 13 - 16 June, 2023, Bucharest, Romania
Projects
Cost- and Energy-Efficient Control Systems for BuildingsCLAS—Cybersäkra lärande reglersystemHiSS—Humanizing the Sustainable Smart CityMarie Skłodowska- Curie
Funder
Swedish Energy Agency, 47859-1Swedish Foundation for Strategic Research, RIT17-0046EU, Horizon Europe, 101062523EU, Horizon Europe, 830927
Note

QC 20230918

Available from: 2023-09-12 Created: 2023-09-12 Last updated: 2023-09-18Bibliographically approved
Farjadnia, M., Alanwar, A., Niazi, M. U., Molinari, M. & Johansson, K. H. (2023). Robust data-driven predictive control of unknown nonlinear systems using reachability analysis. European Journal of Control
Open this publication in new window or tab >>Robust data-driven predictive control of unknown nonlinear systems using reachability analysis
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2023 (English)In: European Journal of Control, ISSN 09473580Article in journal (Refereed) Published
Abstract [en]

This work proposes a robust data-driven predictive control approach for unknown nonlinear systems in the presence of bounded process and measurement noise. Data-driven reachable sets are employed for the controller design instead of using an explicit nonlinear system model. Although the process and measurement noise are bounded, the statistical properties of the noise are not required to be known. By using the past noisy input-output data in the learning phase, we propose a novel method to over-approximate exact reachable sets of an unknown nonlinear system. Then, we propose a data-driven predictive control approach to compute safe and robust control policies from noisy online data. The constraints are guaranteed in the control phase with robust safety margins by effectively using the predicted output reachable set obtained in the learning phase. Finally, a numerical example validates the efficacy of the proposed approach and demonstrates comparable performance with a model-based predictive control approach.

Place, publisher, year, edition, pages
Elsevier BV, 2023
Keywords
Data-driven methods, Nonlinear systems, Predictive control, Reachability analysis, Zonotopes
National Category
Control Engineering
Identifiers
urn:nbn:se:kth:diva-332094 (URN)10.1016/j.ejcon.2023.100878 (DOI)2-s2.0-85165280389 (Scopus ID)
Projects
Cost-and Energy-Efficient Control Systems for BuildingsCLAS—Cybersäkra lärande reglersystemHiSS - Humanizing the Sustainable Smart City, Digital Futures, contract number VF-2020-0260European Union, Horizon Research and Innovation Programme, Marie Skłodowska-Curie grant agreement No. 101062523.
Funder
Swedish Energy Agency, 47859-1Swedish Foundation for Strategic Research, RIT17-0046
Note

QC 20231215

Available from: 2023-07-19 Created: 2023-07-19 Last updated: 2023-12-15Bibliographically approved
Fontan, A., Farjadnia, M., Llewellyn, J., Katzeff, C., Molinari, M., Cvetkovic, V. & Johansson, K. H. (2023). Social interactions for a sustainable lifestyle: The design of an experimental case study. In: : . Paper presented at IFAC World Congress 2023 - The 22nd World Congress of the International Federation of Automatic Control.
Open this publication in new window or tab >>Social interactions for a sustainable lifestyle: The design of an experimental case study
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2023 (English)Conference paper, Published paper (Refereed)
Abstract [en]

Every day we face numerous lifestyle decisions, some dictated by habits and somemore conscious, which may or may not promote sustainable living. Aided by digital technology,sustainable behaviors can diffuse within social groups and inclusive communities. This paperoutlines a longitudinal experimental study of social influence in behavioral changes towardsustainability, in the context of smart residential homes. Participants are students residing inthe housing on campus referred to as KTH Live-In Lab, whose behaviors will be observedw.r.t. key lifestyle choices, such as food, resources, mobility, consumption, and environmentalcitizenship. The focus is on the preparatory phase of the case study and the challengesand limitations encountered during its setup. In particular, this work proposes a definitionof sustainability indicators for environmentally significant behaviors, and hypothesizes that,through digitalization of a household into a social network of interacting tenants, sustainableliving can be promoted.

Keywords
Sustainable behavior, experimental study, Live-In Lab, smart homes, cyber-physical-human systems, social networks.
National Category
Control Engineering Information Systems, Social aspects
Identifiers
urn:nbn:se:kth:diva-336667 (URN)
Conference
IFAC World Congress 2023 - The 22nd World Congress of the International Federation of Automatic Control
Projects
HiSS - Humanizing the Sustainable Smart CityCost-and Energy-Efficient Control Systems for BuildingsCLAS - Cybersäkra lärande reglersystem
Funder
Swedish Energy Agency, 47859-1Swedish Foundation for Strategic Research, RIT17-0046
Note

QC 20231123

Available from: 2023-09-15 Created: 2023-09-15 Last updated: 2023-11-23Bibliographically approved
Walther, K., Molinari, M. & Voss, K. (2023). The role of HVAC controls in building Digital Twins: lessons learned from demonstration buildings with an application to air handling units. In: BS 2023 - Proceedings of Building Simulation 2023: 18th Conference of IBPSA: . Paper presented at 18th IBPSA Conference on Building Simulation, BS 2023, Shanghai, China, Sep 4 2023 - Sep 6 2023 (pp. 2005-2012). International Building Performance Simulation Association
Open this publication in new window or tab >>The role of HVAC controls in building Digital Twins: lessons learned from demonstration buildings with an application to air handling units
2023 (English)In: BS 2023 - Proceedings of Building Simulation 2023: 18th Conference of IBPSA, International Building Performance Simulation Association , 2023, p. 2005-2012Conference paper, Published paper (Refereed)
Abstract [en]

This study investigates how information about the controls of heating, ventilation and air-conditioning (HVAC) systems can be gathered from building automation systems for the creation of Digital Twins in Building Performance Simulation (BPS). The concept of Digital Twins in BPS environments is commonly used for Fault Detection and Diagnosis or performance gap analysis during operation. In the creation, often emphasis is put on building physics or user behavior. In modern buildings, automation systems play an important role to guarantee user comfort requirements as well as an energy efficient operation. To replicate the behavior of real HVAC systems in Building Performance Simulations, the underlying control logic has to be known. To gather this information in operation we have investigated three sources: firstly, documentation from the design phase including already existing simulation models, secondly, the control code on automation systems and thirdly, reverse engineering from measured data. The study focuses on air handling units and is based on experiences in state-of-the-art building demonstrators from research projects in Sweden and Germany.

Place, publisher, year, edition, pages
International Building Performance Simulation Association, 2023
National Category
Building Technologies
Identifiers
urn:nbn:se:kth:diva-341623 (URN)10.26868/25222708.2023.1434 (DOI)2-s2.0-85179512694 (Scopus ID)
Conference
18th IBPSA Conference on Building Simulation, BS 2023, Shanghai, China, Sep 4 2023 - Sep 6 2023
Note

QC 20231228

Available from: 2023-12-28 Created: 2023-12-28 Last updated: 2024-03-11Bibliographically approved
Molinari, M., Anund Vogel, J., Rolando, D. & Lundqvist, P. (2023). Using living labs to tackle innovation bottlenecks: the KTH Live-In Lab case study. Applied Energy, 338, 120877-120877, Article ID 120877.
Open this publication in new window or tab >>Using living labs to tackle innovation bottlenecks: the KTH Live-In Lab case study
2023 (English)In: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 338, p. 120877-120877, article id 120877Article in journal (Refereed) Published
Abstract [en]

The adoption of innovation in the building sector is currently too slow for the ambitious sustainability goals thatour societies have agreed upon. Living labs are open innovation ecosystems in real-life environments usingiterative feedback processes throughout a lifecycle approach of an innovation to create sustainable impact. In thecontext of the built environment, such co-creative innovation and demonstration platforms are needed tofacilitate the adoption of innovative technologies and concepts for more energy-efficient and sustainablebuildings. However, their feasibility is not extensively proven. This paper illustrates the implementation anddemonstrates the feasibility of the Living Labs Triangle Framework for buildings living labs. This conceptualframework has been used to conceive the KTH Live-In Lab, a living lab for buildings. The goal of the Live-In Labwas to create a co-creative open platform for research and education bridging the gap between industry andacademia, featuring smart building demonstrators. The Living Lab Triangle Framework has been deployed tomeet the goals of the Live-in Lab, and the resulting concept is described. This paper then analyses the meth-odological and operational results introducing performance metrics to measure the economic sustainability, thepromotion of multidisciplinary research and development projects, dissemination and impact. The results arecompleted with a SWOT analysis identifying its current strengths and weaknesses. The results collected in thiswork fill a missing gap in the scientific literature on the performance of living labs and provide empirical evi-dence on the sustainability and impact of living labs.

Place, publisher, year, edition, pages
Elsevier BV, 2023
Keywords
Living labs Innovation Building industry Smart buildings Building demonstrators Built environment
National Category
Energy Engineering Building Technologies
Research subject
Energy Technology; Civil and Architectural Engineering, Building Technology
Identifiers
urn:nbn:se:kth:diva-324845 (URN)10.1016/j.apenergy.2023.120877 (DOI)000955580100001 ()2-s2.0-85150014674 (Scopus ID)
Funder
Swedish Energy Agency, 47859-1Swedish Foundation for Strategic Research, RIT17-0046
Note

QC 20230321

Available from: 2023-03-17 Created: 2023-03-17 Last updated: 2023-04-14Bibliographically approved
Farjadnia, M., Fontan, A., Russo, A., Johansson, K. H. & Molinari, M. (2023). What influences occupants' behavior in residential buildings: An experimental study on window operation in the KTH Live-In Lab. In: 2023 IEEE Conference on Control Technology and Applications, CCTA 2023: . Paper presented at 2023 IEEE Conference on Control Technology and Applications, CCTA 2023, Bridgetown, Barbados, Aug 16 2023 - Aug 18 2023 (pp. 752-758).
Open this publication in new window or tab >>What influences occupants' behavior in residential buildings: An experimental study on window operation in the KTH Live-In Lab
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2023 (English)In: 2023 IEEE Conference on Control Technology and Applications, CCTA 2023, 2023, p. 752-758Conference paper, Published paper (Refereed)
Abstract [en]

 Window-opening and window-closing behaviors play an important role in indoor environmental conditions and therefore have an impact on building energy efficiency. On the other hand, the same environmental conditions drive occupants to interact with windows. Understanding this mutual relationship of interaction between occupants and the residential building is thus crucial to improve energy efficiency without disregarding occupants' comfort. This paper investigates the influence of physical environmental variables (i.e., indoor and outside climate parameters) and categorical variables (i.e., time of the day) on occupants' behavior patterns related to window operation, utilizing a multivariate logistic regression analysis. The data considered in this study are collected during winter months, when the effect on the energy consumption of the window operation is the highest, at a Swedish residential building, the KTH Live-In Lab, accommodating four occupants in separate studio apartments. Although all the occupants seem to share a sensitivity to some common factors, such as air quality and time of the day, we can also observe individual variability with respect to the most significant drivers influencing window operation behaviors. 

National Category
Control Engineering Energy Systems
Identifiers
urn:nbn:se:kth:diva-336515 (URN)10.1109/CCTA54093.2023.10253188 (DOI)
Conference
2023 IEEE Conference on Control Technology and Applications, CCTA 2023, Bridgetown, Barbados, Aug 16 2023 - Aug 18 2023
Projects
Cost-and Energy-Efficient Control Systems for BuildingsCLAS–Cybersäkra lärande reglersystemSwedish Research Council Distinguished Professor GrantHiSS - Humanizing the Sustainable Smart CityKnut and Alice Wallenberg Foundation Wallenberg Scholar Grant
Funder
Swedish Energy Agency, 47859-1Swedish Foundation for Strategic Research, RIT17-0046Swedish Research Council, 2017-0107
Note

Part of ISBN 9798350335446

QC 20230913

Available from: 2023-09-12 Created: 2023-09-12 Last updated: 2023-11-01Bibliographically approved
Rolando, D., Mazzotti, W. & Molinari, M. (2022). Long-Term Evaluation of Comfort, Indoor Air Quality and Energy Performance in Buildings: The Case of the KTH Live-In Lab Testbeds. Energies, 15(14), 4955
Open this publication in new window or tab >>Long-Term Evaluation of Comfort, Indoor Air Quality and Energy Performance in Buildings: The Case of the KTH Live-In Lab Testbeds
2022 (English)In: Energies, E-ISSN 1996-1073, ISSN 1996-1073, Vol. 15, no 14, p. 4955-Article in journal (Refereed) Published
Abstract [en]

Digitalization offers new, unprecedented possibilities to increase the energy efficiencyand improve the indoor conditions in buildings in a cost-efficient way. Smart buildings are seen bymany stakeholders as the way forward. Smart buildings feature advanced monitoring and controlsystems that allow a better control of the buildings’ indoor spaces, but it is becoming evident that themassive amount of data produced in smart buildings is rarely used. This work presents a long-termevaluation of a smart building testbed for one year; the building features state-of-the-art monitoringcapability and local energy generation (PV). The analysis shows room for improving energy efficiencyand indoor comfort due to non-optimal control settings; for instance, average indoor temperaturesin all winter months were above 24 ◦C. The analysis of electricity and domestic hot water use hasshown a relevant spread in average use, with single users consuming approximately four times morethan the average users. The combination of CO2 and temperature sensor was sufficient to pinpointthe anomalous operation of windows in wintertime, which has an impact on energy use for spaceheating. Although the quantification of the impact of users on the overall energy performance ofthe building was beyond the scope of this paper, this study showcases that modern commercialmonitoring systems for buildings have the potential to identify anomalies. The evidence collectedin the paper suggests that this data could be used to promote energy-efficient behaviors amongbuilding occupants and shows that cost-effective actions could be carried out if data generated by themonitoring and control systems were used more extensively.

Place, publisher, year, edition, pages
MDPI AG, 2022
Keywords
building energy performance; indoor environmental quality; monitoring system; building system control; smart building
National Category
Building Technologies Energy Engineering
Identifiers
urn:nbn:se:kth:diva-315447 (URN)10.3390/en15144955 (DOI)000831565000001 ()2-s2.0-85134022043 (Scopus ID)
Projects
Cost- and Energy-Efficient Control Systems for Buildings, E2B2 programmeCLAS—Cybersäkra lärande reglersystem, Swedish Foundation for Strategic Research-SSFHiSS—Humanizing the Sustainable Smart City, Digital Futures
Funder
Swedish Energy Agency, project number 47859-1Swedish Foundation for Strategic Research, RIT17-0046
Note

QC 20220728

Available from: 2022-07-07 Created: 2022-07-07 Last updated: 2023-08-28Bibliographically approved
Organisations
Identifiers
ORCID iD: ORCID iD iconorcid.org/0000-0002-2300-2581

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