Conference Agenda

Overview and details of the sessions of this conference. Please select a date or location to show only sessions at that day or location. Please select a single session for detailed view (with abstracts and downloads if available).

Please note that all times are shown in the time zone of the conference. The current conference time is: 5th July 2022, 13:50:31 CEST

 
 
Session Overview
Session
Session W1.5: The role of occupants
Time:
Wednesday, 01/Sept/2021:
10:30 - 12:00

Session Chair: Fabian Ochs, University of Innsbruck
Session Chair: Valentin Gavan, ENGIE Lab CRIGEN
Location: Concert Hall - Kamermuziekzaal
't Zand 34, Bruges

External Resource: Click here to join the livestream. Only registered participants have received the access code for the livestream.
Show help for 'Increase or decrease the abstract text size'
Presentations
10:30 - 10:48

Influence of the hydronic loop configuration on the energy performance of a CO2 heat pump for domestic hot water production in a multi-family building

Matteo Dongellini, Claudia Naldi, Gian Luca Morini

Department of Industrial Engineering, University of Bologna, Italy

Aim and Approach

(max 200 words)

Nowadays the impact of domestic hot water (DHW) production on the overall energy consumption of a building is significantly increasing. In fact, a strong effort has been made to improve the building envelope insulation properties and the efficiency of HVAC systems for space heating and cooling, while, on the contrary, a lower attention has been focused on the reduction of the energy need related to DHW preparation. Although it accounts for about the 19% of the total energy demand of European Union residential sector [1], this percentage is expected to increase up to 50% in the next years [2]. CO2 heat pumps are promising solutions to achieve significant energy savings for DHW production; furthermore, CO2 is characterized by a low GWP value, is economic and environmentally sustainable [3]. In this paper the annual energy performance of a centralized plant for DHW production in a multi-family building located in Bologna (Italy) and based on an air-to-water CO2 transcritical heat pump has been assessed by means of TRNSYS and compared with the results of a monitoring campaign performed for three months during the winter season of 2017-2018.

Scientific Innovation and Relevance

(max 200 words)

The multi-family residential building considered in this work is composed by 7 stories and 27 flats, for a total useful surface of about 3850 square meters. A particular effort has been made to determine the hot water tap profile of the whole building: the method presented in Reference [4] has been used and adapted to the selected application. A hourly draw-off profile which takes into account the contemporaneity factor of the hot water request among all the apartments has been defined for both workdays and weekends. Moreover, the dynamic model of the CO2 heat pump has been developed with the cooperation of the heat pump manufacturer, who provided the performance data of the unit and its control logic. In order to decrease the temperature of the fresh water entering the heat pump, two water storages are connected in series with the unit. This work allows to evaluate the influence of the hydronic loop configuration on the energy performance of a CO2 heat pump: dynamic simulations evidenced that the configuration initially adopted for the DHW distribution was not able to exploit the maximum energy saving potential of this kind of heat pump units.

Preliminary Results and Conclusions

(max 200 words)

The comparison between experimental and numerical results showed that the CO2 heat pump effective energy performance were much lower than that expected if the heat pump had been conducted in an optimal way. More in detail, the measured average heat pump performance factor (SPF) during the monitored period was 1.66, while, on the other hand, the unit energy performance calculated with dynamic simulations for the same interval could reach values close to 4.70. The analysis pointed out that this strong reduction of the heat pump performance was caused by the configuration of the DHW loop: with the adopted solution, thermal stratification within the storage was not obtained and the temperature of the water at the inlet of the heat pump was very high. For this reason, the unit efficiency dramatically decreases. Experimental data confirms this hypothesis: the temperature of the water stream entering the heat pump was around 40°C, almost 25 K higher than fresh water temperature introduced in the thermal storage vessel from the aqueduct. The results obtained in this work highlight how the energy performance of CO2 heat pumps is significantly influenced by the configuration of the DHW loop and especially by the layout of the thermal storages.

Main References

(max 200 words)

[1] T. Kitzberger, D. Kilian, J Cotik, T. Proll, Comprehensive analysis of the performance and intrinsic energy losses of centralized Domestic hot Water (DHW) systems in commercial (educational) buildings, Energy and Buildings 195 (2019), 126-138.

[2] A. Bertrand, A. Mastrucci, N. Schuler, R. Aggoune, F. Maréchal. Characterisation of domestic hot water end-uses for integrated urban thermal energy assessment and optimization, Applied Energy 186 (2017), 152-166.

[3] k. Visser, Transcritical CO2 refrigeration systems for building cooling and heating reduce energy and cooling water consumption, emissions and the legionella danger, Proceedings of the 8th International Conference on Advances in Applied Science and Environmental Engineering (ASEE 2018), 3-4 February 2018, Kuala Lumpur, Malaysia.

[4] K. Ahmed, P. Pylsy, J. Kurnitski, Hourly Consumption profiles of domestic hot water for different occupant groups in dwellings, Solar Energy 137 (2016), 516-530.



10:48 - 11:06

Methods for determining occupant behavioural models for energy-efficient retrofitting of 20th-century buildings

Antonella Mastrorilli1, Roberta Zarcone2, Chenafi Sabrina1, Colonneau Téva1

1Laboratoire LACTH, Ecole Nationale Supérieure d’Architecture et de Paysage de Lille, 2 Rue Verte, 59650 Villeneuve-d'Ascq, France; 2Laboratoire GSA, Ecole Nationale Supérieure d’Architecture Paris-Malaquais, 14 rue Bonaparte, 75006 Paris

Aim and Approach

(max 200 words)

A study carried out within the project "Rethinking innovation. Know and manage the legacies of experiment and innovative social housing from the decade 1968-78” funded by the French Ministry of Cultural, is presented in this paper. The objective of this research is to highlight the influence of the variable occupancy in an energy renovation scenario.

We present the methodology developed for the construction of a "detailed" inhabitant profile on a case study of the social housing “Residence Salamandre” in Villeneuve d'Ascq.

By using an interoperable work, we produced a digital model informed by BIM methods, combining the sharing of information tasks of existing construction and site conditions.

From the typo-morphological analysis of the housing modules, a phase of data collection on the lifestyles of different occupants of the residence was developed. The balance sheet of energy consumed by year (provide by inhabitants) and anonymous surveys made it possible to link the aspect of daily consumption to the question of lifestyles.

In this paper, we present the impact of internal contributions on energy performance by comparing the results with those resulting from the application of usage scenarios in accordance with the French RT2012 standard.

Scientific Innovation and Relevance

(max 200 words)

Today, the influence of occupants’ behaviour is oversimplified during the analysis phases prior to energy renovation operations.

Amongst other variables, the lifestyles of the occupants remains one of the most difficult to control. However, it seems to play a decisive role because it represents one of the main factors of discrepancy between the phases of energy renovation and the actual functioning of a building.

Assessing energy needs and performance of existing buildings therefore, requires calculation tools able to produce results that are closest to reality. However, the different energy simulation softwares show many disparities which often leads to different results. In addition, the application of thermal regulations requires the use of referenced conventional calculation methods (DPE, TH BCE Method), certifying a level of energy performance to reach, by combining the analysis of "real" data with those of predetermined data, from hypothetical use scenarios.

This research attempted to develop dynamic energy simulation methods, offering the most realistic representation of energy needs in use conditions. We have defined a "fine" analysis methodology which allowed to take into account the variable of occupancy in housing. This will make us quantify its impact on energy needs and prefigure the most appropriate energy intervention.

Preliminary Results and Conclusions

(max 200 words)

According to the simulations carried out through numerical modelling and the characterisation of a "detailed" user profile - for a family of three people - the first results obtained have demonstrated the impact of Inhabitants users in the calculation of consumption needs.

In fact, in the case of the “detailed” user profile, the internal contributions cover a total of 40% of the home's heating needs, i.e. 10% more than the results obtained considering the conventional profile from the French standard RT2012.

The results then highlighted a striking observation: Through dynamic energy building simulation, the occupancy variable in “detailed” user profile shows more efficient alternative than the intervention in external over-insulation of the Salamandre residence, with a strong aesthetic and constructive impact as a whole. Resorting to a "fine" analysis on a case-by-case basis - provide by actual measurements of occupancy variables in the dwelling - might then be more appropriate, in order to preserve the original aesthic and material qualities of building heritage objects.

Therefore, the conceptual and technical results obtained in this research aim to generalize this analysis methodology prior to each energy renovation project for existing buildings.

Main References

(max 200 words)

Fabi V, Andersen RV, Corgnati SP, Olesen BW. A methodology for modelling energy-related human behaviour: application to window opening behaviour in residential buildings. Build Simul 2013 6:415

Andersen RV, Toftum J, Andersen KK, Olesen BW (2009), “Survey of occupant behaviour and control of indoor environment”, Danish dwellings. Energy and Buildings, 41: 11–16

Andersen RV (2012), “The influence of occupants’ behaviour on energy consumption investigated in 290 identical dwellings and in 35 apartments”, Proceedings of Healthy Buildings 2012, Brisbane, Australia.

Brundrett GW (1997), “Ventilation: A behavioural approach”, International Journal of Energy Research, 1: 289–298. Emery AF, Kippenhan CJ (2006), “A long term of residential home heating consumption and the effect of occupant behavior on homes in the Pacific Northwest constructed according to improved thermal standards”, Energy, 31: 677-693.

Geslin F., Le bâti ancien appelle des solutions non standardisées, Les cahiers techniques du bâtiment, (https://www.cahiers-techniques-batiment. fr/article/le-bati-ancien-appelle-des-solutions-non standardisees.32324, consulté le 28/03/2017).

Nicol JF, Humphreys MA (2004), “A stochastic approach to thermal comfort-occupant behaviour and energy use in buildings”, ASHRAE Transactions, 110(2): 554–68.



11:06 - 11:24

Human in the Loop: perceived based control as the key to enhance buildings’ performance

Davide Calì, Christian Ankerstjerne Thilker, Sebastian Arcos Specht, Jaume Palmer Real, Henrik Madsen, Bjarne W. Olesen

DTU, Denmark

Aim and Approach

(max 200 words)

The performance gap of existing and new buildings [1], both in terms of energy and occupants’ comfort, jeopardizes the effort to reach deep decarbonization target. One of the main issues causing high CO2 emissions of buildings is related to VOLATILITY. Buildings are mostly planned and controlled based on assumptions and fixed schedules which might were valid in the Sixties. However, our society evolved: For example, residential buildings where family lives are often empty during the day while both parents go to work and children stay until afternoon at schools; in parallel, work-from-home became reality, also several times a week. Moreover, not only the demand for comfort is volatile: to minimize buildings’ impact on climate change, we have to maximize the use of renewable energy sources. As a consequence, the production of energy is non-projectable. Matching the volatile usage of buildings with intermittent energy production can help both enhancing personal comfort and reducing CO2 emissions caused by the existing building stock. In this work, we propose a Human-in-the-Loop approach, where occupants are traced within a building, and, when they desire it, can provide feedback about their perceived comfort in specific rooms: this feedback is then used to control the building.

Scientific Innovation and Relevance

(max 200 words)

The provision of flexibility services to the energy grids became more popular in the last decade. However, too often flexibility projects have a strong focus on the quality of the services provided to the grid, and do not actively consider real occupants needs. Eventually, flexibility services are connected to a deficit of indoor comfort (e.g. accepting lower indoor temperature or lower air change per hour). Through the use of our tracing and feedback app “FEEDME” and a network of IoT sensors connected to our vendor-neutral monitoring platform CLIMIFY [2], we gather information regarding the number of occupants within a room, their live feedback on the indoor climate, and their past preferences at given indoor conditions. This information can be used to:

1. Simplify the way buildings are controlled: instead of asking the occupants to choose set points, we ask how she/he feels, and control the building accordingly

2. Take into account the diversity of occupants’ needs, and also the way those needs change during the day in the control of buildings - Mediate among different needs in a democratic way;

3. Optimize energy use, CO2 emissions and indoor climate in buildings through model predictive control and AI.

Preliminary Results and Conclusions

(max 200 words)

FEEDME and CLIMIFY are currently being tested in a school with 13 classrooms, located in Denmark (a second demonstration office building is under arrangement). In the school, we gathered the feedback of occupants on their perceived thermal comfort (using a 5-steps scale) for a period of 6 weeks. In a first 3-week period, the set-point of smart thermostats was for all classrooms set to 22°C: 51% of the occupants were fully satisfied with the indoor climate, while over 10% were completely dissatisfied. In the second 3-week period, the set points of each classroom were manually adjusted accordingly to the received feedback of the previous 3 weeks. As a result, over 63% of occupants were fully satisfied, only 6% was fully unsatisfied [5]. In this first experiment, we only adjusted the set-point once, and accordingly to the location were the feedback was given only. A real time optimization, considering the exact occupants in each classroom and adjusting also other set-points, such as ventilation and blinds, could further enhance occupants experience in buildings. FEEDME keeps the occupants in the middle of the control loop but minimizes human errors. Moreover, the indoor climate enhancement is reflected into higher productivity [4, 5].

Main References

(max 200 words)

[1] D Calì, T Osterhage, R Streblow, D Müller, Energy performance gap in refurbished German dwellings: Lesson learned from a field test - Energy and buildings, 127 (2016), 1146-1158. https://doi.org/10.1016/j.enbuild.2016.05.020

[2] Calì, D., Kindler, E., Ebrahimy, R., Bacher, P., Hu, K. S., Østrup, M. L., Bachalarz, M., & Madsen, H. (2019). climify.org: an online solution for easy control and monitoring of the indoor environment. E3S Web of Conferences, 111. https://doi.org/10.1051/e3sconf/201911105006

[3] D. Calì, Results of data analysis and optimization algorithms - Technical Report, DTU, 2020.

[4] P. Wargocki, J.A. Porras-Salazar, S. Contreras-Espinoza, The relationship between classroom temperature and children’s performance in school, Build. Environ. 157 (2019) 197–204. https://doi:10.1016/j.buildenv.2019.04.046

[5] P. Wargocki, J.A. Porras-Salazar, S. Contreras-Espinoza, W. Bahnfleth, The relationships between classroom air quality and children’s performance in school, Build. Environ. 173 (2020). https://doi:10.1016/j.buildenv.2020.106749



11:24 - 11:42

A simulation workflow for exposure characterisation of daylit spaces based on occupant gaze orientation

Mandana Sarey Khanie1, Mikkel Kofod Pedersen1, Trine Illum1, Rasmus Nielsen1, Thorbjøn Asmussen2

1Technical University of Denamrk, Denmark; 2VELUX A/S, Hoersholm, Denmark

Aim and Approach

(max 200 words)

This paper represents a simulation workflow for characterization of spectral exposure depending on occupants’ position and gaze behavior in buildings. The project uses existing gaze movement database as well as occupant-tracking data obtained in a pilot study for its development. The existing database has been obtained at a daylight lab at Freiburg, Germany, in a user-assessment study where eye-tracking systems were used to record visual responses to the luminous environment [1]. The pilot study was done over a period of 2 months where occupants’ orientations were tracked using an image-based sensors recoding dwells and movements of occupant. The dwell and track data from the pilot study were used to define exposure ranges to spectral effectiveness of the space. Using the two databases , a Grasshopper3D tool was developed to demonstrate gaze behavior[1], [2], exposure to illumination levels, and the exposure to spectral lighting, thus allows for exposure characterization of the space at the eye level at each given position. The latter was processed using Lark Spectral Lighting tool [3] to account for photopic, Rea[4] and Lucas [5]circadian illuminance. Using the tool, a simulation study was done and the results as well as the work flow are presented here.

Scientific Innovation and Relevance

(max 200 words)

Despite different existing wavelength-dependent models to predict spectral-effectiveness of light[6], [7], these methods can only predict the health potentials in a space with assumption of static building occupants on fixed pre-defined points[8]. With great benefits on our well-being [9], [10], an exposure characterization of space for daylight, based on dynamic occupant behavior is a step forward. This step allows for better understanding occupant well-being indoors based on actual occupant’s position and orientation. The dynamic human behavior to light exposure has been addressed in fewer studies where photometric measurements and eye-tracking methods were coupled for observations of gaze or eye responses to light [1], [11]. Building up on these exiting methodologies, here the occupant light-driven behavior is used to predict the exposure to spectral lighting and illumination levels in space. In addition, data gathered by the sensors are processed to show the actual exposure levels in real time. The developed tool and processing method can be used in design phases to introduce interventions, e.g. change of interior layout, for optimal lighting solutions.

Preliminary Results and Conclusions

(max 200 words)

The simulation study provided a clear demonstration of visual patterns and exposure patterns at different points in space based on the dynamic occupant behavior. The health potential of the selected dominant gaze orientation was evaluated at each position. From the Lark tool [6], the values had to be converted as the selected threshold values used the units Circadian Stimulus (CS) and Equivalent Melanopic Lux (EML). The threshold value CS explained the optimal stimulus throughout the working day, where specific values are given for each hour, while the threshold value EML gave a fixed value over all hours. While most positions in the models showed satisfactory during summer time and under sunny conditions, only fewer positions would reach the thresholds under overcasts skies. Hence, optimized use of such areas in certain climatic regions proves to be essential. Moreover, as in north façade and lack of visual discomfort allows for orienting towards windows, higher health potentials can be achieved. It can therefore be concluded that the orientation in space is crucial for the vertical illuminance measured at the eye, but it is still important that the visual comfort is maintained.

Main References

(max 200 words)

1. Sarey Khanie, M., et.al. Gaze and discomfort glare, Part 1: Development of a gaze-driven photometry. Light. Res. Technol. (2016)

2.Sarey Khanie, M. et al. A Gaze Visualizer tool for Grasshopper3d. in SimBuild – USA, (2018)

3. Inanici, M., et.al. Spectral daylighting simulations, Department of Architecture, Seattle, USA

4. Rea, M. The lumen seen in a new light, Light. Res. Technol. 47, (2015)

5.Lucas, R. et al. Measuring and using light in the melanopsin age. Trends in Neurosciences (2014).

6.Amundadottir,M. et.al. Unified framework to evaluate non-visual spectral effectiveness of light for human health. Light. Res. Technol. 49, (2017)

7. Rea, M., et.al. A new approach to understanding the impact of circadian disruption on human health. J Circadian Rhythm. 6, (2008)

8.Amundadottir, M. et.al. A human-centric approach to assess daylight in buildings for non-visual health potential, visual interest and gaze behavior. Build. Environ. 113, (2017)

9. Lockley, S. Circadian Rhythms: Influence of Light in Humans. Encycl. Neurosci. 2, (2009)

10.Birchler-Pedross, A. et al. Subjective Well-Being Is Modulated by Circadian Phase, Sleep Pressure, Age, and Gender. J. Biol. Rhythms 24, (2009)

11.Lin, Y. et al. Eye movement and pupil size constriction under discomfort glare. Invest. Ophthalmol. Vis. Sci. 56, (2015)



11:42 - 12:00

Quantifying household specific self-consumption of photovoltaic-based power generation in energy efficient buildings – a comprehensive parametric study to increase the reliability of energy consulting

André Müller1,2, Johannes Koert2, Patrick Wörner2

1Institute for Housing and Environment, Germany; 2Institute of Concrete and Masonry Structures, Technische Universität Darmstadt, Germany

Aim and Approach

(max 200 words)

The energy consumption from private households is responsible for a substantial share of the total greenhouse gas emissions in Germany. For this reason, German legislation promotes the climate-neutral operation of buildings until 2050. Consequently, building related power generation from renewable energies can be considered in the calculation of energy performance according to the German Energy Saving Ordinance (EnEV). However, the EnEV calculation rules allow neither for a proper estimation of the amount of renewable energy generated locally from PV nor for the estimation of private electricity consumption. Thus, the assessments of PV systems to be installed on buildings lack reliability and highly depend on the modelling skills of the energy consultant. To overcome this barrier for the implementation of building-related PV an easy applicable matrix of energy generation and private consumption for different locations as well as types of buildings and households is developed. This is achieved by feeding IDA ICE building simulation models with profiles generated by the user behaviour model ‘PeakTime’. Typical user behaviour of certain household types is translated to annual power consumption profiles, added to the load profiles of building archetypes and compared to the electrical power generation profiles from a PV system.

Scientific Innovation and Relevance

(max 200 words)

A variety of studies already exist on the self-consumption of power production from building related PV systems. However, most of these narrowed research down to a single or respectively a few real or typical households’ electricity consumption. Thus, the results allow for a plausible estimation of self-consumption, but not for a detailed prognosis and quantification as the source of reliable energy consulting. The basis of the presented investigation on household-type specific PV self-consumption is a recently developed stochastic user behaviour model, which allows the generation of load profiles for power consumption of various household configurations. Thereby, household specific circumstances, e.g. the co-use of electrical appliances by two or more household members, and their effect on households’ load profiles are reflected. The relevance arises from the fact that, besides calculated standard load profiles for household types, a distribution of self-consumption from PV systems emerges. To allow for a proper comparison of available technologies and energy performance levels, the household load profiles are processed in a parametric study within the building simulation software IDA ICE. The results of these simulations are categorized and summarized to achieve applicability in the context of energy consulting and allow for more profound decisions of building owners.

Preliminary Results and Conclusions

(max 200 words)

The preliminary results illustrate the fact, that power consumption of household types differ dependent on the status of employment household members and the presence of kids, respectively. At the same time, the amount of self-consumption from PV generated power is highly correlated to the user behaviours underlying the household types. While energy performance calculations according to German EnEV calculation rules cannot reflect these variations, the performed parametric study gives reliable values for self-consumption in general as well as ratios of solar coverage of the use cases heating and cooling, hot water demand as well as other electrical appliances of a household. Thereby, the preliminary results build on a reduced number of available household types and represent an intermediate step on the way of making available realistic user behaviour data for energy performance calculations as well as dynamic building simulations.

Main References

(max 200 words)

Yan, Da ; Hong, Tianzhen; Dong, Bing; Mahdavid, Ardeshir; D’Oca, Simona; Gaetanie, Isabella; Fenga, Xiaohang (2017): IEA EBC Annex 66: Definition and simulation of occupant behavior in buildings. Energy and Buildings, Volume 156, Pages 258-270.

Wörner, Patrick (in Press): Einfluss des Nutzerverhaltens auf den Stromverbrauch in Wohngebäuden ‐ Entwicklung eines komplexen Simulationsmodells für energetische Analysen. Dissertation. Institute of Concrete and Masonry Structures, Technische Universität Darmstadt. Graubner, Carl-Alexander (Ed.)

Loga, Tobias; Frank, Milena (2016): Photovoltaic power generation to cover domestic power demand in Passive House: A parameter study. 20th International Passive House Conference 2016: 22th – 23th April 2016, Darmstadt: Proceedings / Passive House Institute. Feist, Wolfgang (Ed.)

https://www.iwu.de/fileadmin/user_upload/dateien/energie/neh_ph/2016_passivhaustagung_LogaFrank_PVEigendeckungImPassivhaus.pdf (German version; English version is available to the author as print version only; last access: 31.07.2020)

Gaetani, Isabella; Hoes, Pieter-Jan; Hensen, Jan L.M. (2018): Estimating the influence of occupant behavior on building heating and cooling energy in one simulation run. Applied Energy, Volume 223, Pages 159-171.

BMUB (2016): Climate Action Plan 2050 – Principles and goals of the German government’s climate policy. Federal Ministry for the Environment, Nature Conservation, Building and Nuclear Safety (Ed.).

https://www.bmu.de/en/publication/climate-action-plan-2050/ (Last access: 31.07.2020)



 
Contact and Legal Notice · Contact Address:
Privacy Statement · Conference: Building Simulation 2021
Conference Software - ConfTool Pro 2.6.143+TC
© 2001–2022 by Dr. H. Weinreich, Hamburg, Germany