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Occupant behavior towards manual solar shading systems affects the energy performance of buildings. Behavior depends on several aspects which interact in a nontrivial way. This paper presents a simple prediction model of behavior based on self-reported use of manual shading and a user survey. The specific model is applicable to the case study building, which is an office building in Gothenburg, Sweden, but the approach can be extended to other buildings. The model was tested against a hypothetical automated solar shading system for the same building. The results show that cooling loads increased by at least 25 % with the manual model in respect to the automatic system due to fewer blind movements. The results show that not accounting for occupant behaviour leads to a significative performance gap between predicted and actual building energy use.

This article presents and discusses the lessons learned from the monitoring of 25 integrated daylighting and electric lighting international case study projects. The case studies consist of real occupied buildings that have been monitored as part of the International Energy Agency (IEA) SHC Task 61/EBC Annex 77 Programme. The general goal of the case studies was to balance lighting energy use with occupants’ visual and non-visual requirements. This was achieved using innovative solutions for daylighting and electric lighting with advanced controls, but also implementing simple and out-of-the-box strategies. The findings suggest that energy demands for lighting can significantly be reduced by combining sensible daylight provision, efficient lighting sources, and advances in controls. Yet, the effective achievement of project goals requires adequate monitoring, fine-tuning, and verification. The findings also suggest that the adoption of “integrative” lighting – that is, lighting systems that address both visual and non-visual responses – is getting increasingly popular. Catering to non-visual requirements will likely drive further innovation in lighting technology. Currently, there is limited investment available for developing daylighting systems for integrative lighting, and the current related electric strategies often come at the risk of energy rebound effects. Overall, providing daylighting and understanding user requirements are fundamental steps towards achieving quality projects, with potential benefits beyond saving energy.

This article presents and discusses the lessons learned from the monitoring of 25 integrated daylighting and electric lighting international case study projects. The case studies consist of real occupied buildings that have been monitored as part of the International Energy Agency (IEA) SHC Task 61 / EBC Annex 77 Programme. The general goal of the case studies was to balance lighting energy use with occupants’ visual and non-visual requirements. This was achieved using innovative solutions for daylighting and electric lighting with advanced controls, but also implementing simple and out-of-the-box strategies. The findings suggest that energy demands for lighting can significantly be reduced by combining sensible daylight provision, efficient lighting sources, and advances in controls. Yet, the effective achievement of project goals requires adequate monitoring, fine-tuning, and verification. The findings also suggest that the adoption of “integrative” lighting – that is, lighting systems that address both visual and non-visual responses – is getting increasingly popular. Catering to non-visual requirements will likely drive further innovation in lighting technology. Currently, there is limited investment available for developing daylighting systems for integrative lighting, and the current related electric strategies often come at the risk of energy rebound effects. Overall, providing daylighting and understanding user requirements are fundamental steps towards achieving quality projects, with potential benefits beyond saving energy.

This paper explores social interaction in local public squares under different lighting conditions. At its best public squares are social spaces that engender a sense of belonging, increase the quality of life and wellbeing of individuals. It is proposed that outdoor lighting would be essential to the use of the public realm after dark, but empirical results regarding lighting conditions and social aspects of life in public squares are limited. Based on a socio-physical conceptual model of the transactional relationship of the user, the lit environment andthe behavioural outcome, this study investigated active social interaction in daylight compared to after dark. A field study was conducted in two local public squares in Malmö, Sweden. The occurrences of which visitors were being alone, in pairs, or in groups of three or more (N=2522), and verbal or non-verbal interaction amongst those in company of another person were recorded.The lit appearance of the two squares after dark, was assessed with HDR-photography and photometric measurements; portraying dissimilar spatial, spectral and intensity characteristics.The results of social interaction show dissimilar patterns of the two squares; an increase in social interaction in EL after dark was observed in one of the squares, while a decrease in the afternoon and no significant difference was displayed in the evening after dark in the other square. It is suggested that lighting may sustain patterns of social interaction after dark, however it might be, that the company of another is especially important after dark.

Low energy buildings are key to reduce global energy use. However, achieving low energy use and good daylight levels simultaneously in dense cities is challenging. This article reviews relevant studies dealing with energy use and daylighting in dense residential urban blocks located in Nordic climates. The literature review combines a systematic and a ‘snowball’ search approach. Findings indicate that previous research relies heavily on parametric design as a tool. Few density metrics were found particularly relevant to describe the interplay between density, daylight, and energy use.However, the limited body of research achieved so far in the Nordic climate makes it difficult to draw a clear conclusion, suggesting that additional research is required.

Building performance predictions and their reliability rely heavily on weather data inputs. Climate is affected by spatial and temporal differences related to climate change and urban heat island effects, but the weather files used in building performance simulations (BPS) often remain unchanged and may represent weather observations generated from inadequate space and time for their application. This study investigated Swedish weather data using statistical methods and analysed i) the local differences related to rural and urban microclimates and ii) the country-wide differences linked to climate change; by comparing recent observation data to the respective EnergyPlus Weather (EPW) files. The findings reveal that there are significant differences between rural and urban temperature means, and that outdated model years of weather data files make them unsuitable for BPS. The impact of using an inadequate weather file based on changes in recent climate in Sweden can lead to an overestimation of heating demand by 6.5 % on average, while the impact is higher for warmer climates-up to 12 %. The combined impact including climate change and urban heat island effects can lead to a heating energy overestimation by 12 % to 19 %, based on the Stockholm example. On the other hand, it was found that although the global radiation means saw a slightly increasing trend, its impact on the BPS remains inconclusive. The study highlights the importance of selection of adequate weather data for BPS keeping in mind the spatial and temporal influencing factors.

Achieving good daylighting and electrical lighting design in buildings to attain both energy savings and benefits for human health remains a challenge. On the one hand, glass façades designed to maximize daylight harvesting and views are sources of glare (Hirning, Isoardi et al. 2013), and adaptive changes made by occupants to achieve visual comfort (e.g. use of blinds, electrical light) increase energy use (Amirkhani, Garcia-Hansen et al. 2018, Pham, Wagdy et al. 2019). On the other hand efficient LEDs have created a rebound effect of increased use of lighting due to the reduce cost, increasing the overall energy use (Kyba, Kuester et al. 2017). While field study research (Williams, Atkinson et al. 2012) has highlighted potential energy savings (18 to 60%) of daylighting/electrical integration strategies such as personal control, daylighting harvesting, occupant sensing, and tuning; others (Gentile, Osterhaus et al. 2019) suggest that user-driven strategies may not always materialize the energy savings, and energy efficiency and user behaviour in the context of integrated lighting needs to be further explored.

This report presents tools for post-occupancy evaluation (POE) to evaluate indoor lighting of commissioned projects (‘case studies’) under a common framework. In this report, POE includes technical environmental assessment (TEA) and observer-based environmental assessment (OBEA). The framework proposed in this report evaluates four key aspects of the case study: 1. Energy use (electrical lighting systems), 2. Visual effects (Indoor lighting environment /photometry) 3. Non-visual effects (circadian potential), and 4. The user (subjective/surveys and observations) The report targets industry professionals, building designers, lighting designers, building managers, researchers and/or owners wishing to evaluate projects where lighting is supplied by a combination of electrical lighting, daylighting systems (e.g., fenestrations) and assisted technologies (e.g., smart sensors). The framework in this report makes available methods and procedures related to the evaluation of integrated lighting performance in residential and non-residential buildings and its impact on users, and it summarises and categorize methods and procedures in an accessible and industry-oriented language. The content of this document is based on methods and procedures used by participating experts in IEA SHC Task 61 for monitoring twenty-five worldwide integrated daylighting and electric lighting case studies. Since integrated lighting projects are different in type and scopes, the methods and procedures included in the framework do not follow a rigid protocol. Practitioners should use the framework to define the scope of POE monitoring in terms of the aims of the project, context, and resources available. The document is thus a toolbox for planning and executing the monitoring of their integrated lighting projects.

This report presents lessons learned from twenty-five worldwide real-life case studies implementing the integration of daylighting and electric lighting. The case studies were monitored with respect to energy use for lighting, visual performance, non-visual performance, and users’ satisfaction. The monitoring is largely based on field measurements, but it is also complemented with simulations and calculations where needed. The report is divided in two parts. The first part provides an overview of the case studies and the overall lessons learned. The second part provides factsheets for each of the case studies; the factsheets include details on the monitoring, results, and specific lessons learned. Based on the lessons learned from the case studies, this report concludes that: • The energy demand for lighting is drastically reduced thanks to the combined effect of more efficient light sources, advances in controls, and raised awareness in the integration of daylighting and electric lighting. • Integrative lighting is currently driving the innovation in lighting technology and wider implementation is expected as knowledge in the field of non-visual requirements for lighting expands. • However, the current integration of the integrative lighting concept with daylighting in practice is limited, which may result in significant energy rebound (increases). • Daylighting integration is of utmost importance for achieving quality beyond energy savings. • Integrated daylighting and electric lighting design is facing new challenges: questions connected with comfort and health are yet to be answered.

This report presents lessons learned from twenty-five worldwide real-life case studies implementing the integration of daylighting and electric lighting. The case studies were monitored with respect to energy use for lighting, visual performance, non-visual performance, and users’ satisfaction. The monitoring is largely based on field measurements, but it is also complemented with simulations and calculations where needed. The report is divided in two parts. The first part provides an overview of the case studies and the overall lessons learned. The second part provides factsheets for each of the case studies; the factsheets include details on the monitoring, results, and specific lessons learned. Based on the lessons learned from the case studies, this report concludes that: • The energy demand for lighting is drastically reduced thanks to the combined effect of more efficient light sources, advances in controls, and raised awareness in the integration of daylighting and electric lighting. • Integrative lighting is currently driving the innovation in lighting technology and wider implementation is expected as knowledge in the field of non-visual requirements for lighting expands. • However, the current integration of the integrative lighting concept with daylighting in practice is limited, which may result in significant energy rebound (increases). • Daylighting integration is of utmost importance for achieving quality beyond energy savings. • Integrated daylighting and electric lighting design is facing new challenges: questions connected with comfort and health are yet to be answered.

Measures for the reduction of electric energy loads for lighting have predominantly focussed on increasing the efficiency of lighting systems. This efficiency has now reached levels unthinkable a few decades ago. However, a focus on mere efficiency is physically limiting, and does not necessarily ensure that the anticipated energy savings actually materialize. There are technical and non-technical reasons because of which effective integration of lighting solutions and their controls, and thus a reduction in energy use, does not happen. This literature review aims to assess the energy saving potential of integrated daylight and electric lighting design and controls, especially with respect to user preferences and behaviour. It does so by collecting available scientific knowledge and experience on daylighting, electric lighting, and related control systems, as well as on effective strategies for their integration. Based on this knowledge, the review suggests design processes, innovative design strategies and design solutions which – if implemented appropriately – could improve user comfort, health, well-being and productivity, while saving energy as well as the operation and maintenance of lighting systems. The review highlights also regulatory, technical, and design challenges hindering energy savings. Potential energy savings are reported from the retrieved studies. However, these savings derived from separate studies are dependent on their specific contexts, which lowers the ecological validity of the findings. Studies on strategies based on behavioural interventions, like information, feedback, and social norms, did not report energy saving performance. This is an interesting conclusion, since the papers indicate high potentials that deserve further exploration. Quantifying potential savings is fundamental to fostering large scale adoption of user-driven strategies, since this would allow at least a rough estimation of returns for the investors. However, such qua

Research have shown that the correct integration of daylight and electric lighting reduces the energy use in buildings, while improving visual comfort. Smart shading systems, especially those electrically controlled, play an important role to control solar radiation. Similarly, smart and dimmable/tunable lighting can help to adjust the artificial light to the real users' needs. This paper presents preliminary results of an ongoing living lab study investigating how artificial lighting systems can be integrated with shading systems, placing human comfort at the heart of the study and yet saving energy. A manually controlled, commercial and low-cost smart system integrating two motorized shading devices and six dimmable LED luminaires with a different selection of CCT were installed in a private office in a historical building. Indoor and outdoor lighting conditions and energy consumption associated to the lighting system are constantly monitored to assess how the people use shading and lighting upon varying the boundary conditions.. Preliminary results highlight that users prefer to maximise daylight on the work plane as well as they generally use both shading and electric lighting systems in response to boundary conditions that cause serious discomfort.

This paper presents basic data of the energy demand for district heating and plug loads logged by a building management system of an energy-efficient academic building located in Lund, Sweden. The data refers to the years 2019 and 2020 when occupancy varied significantly due to the Corona pandemic. The data shows that the building energy demand adapts poorly to fluctuating occupancy rates. With a possible increase of smart working in the future, building codes should account for more fluctuating occupancy rates in the modelling of the energy demand of buildings.

This report summarizes a survey performed in eight countries on the status quo of daylight and electric lighting control systems. Feedback from more than 100 international experts (building / facility managers and planers) was evaluated. The aim of the survey was to identify the perception of the different possibilities of the current lighting control solutions and the expectations about the control systems. The survey aims to provide a mapping of the current lighting control systems available at the market and an overview of which functions are perceived as most important and which areas are found to be improved. Participants of the survey had to rank each question in relation to the perceived importance and the need for improvement. The survey enclosed five general topics; energy, operational aspects, occupant control, occupant comfort and control functionality.The findings from the summary suggest, that the two main reasons for the implementation of lighting control systems are:1. The possibility to reduce the electric lighting consumptions and2. The opportunity to increase the user’s well-being and thereby reduce complaints from the users.From a user perspective, this means that the lighting system must ensure visual acuity and comfort by providing a sufficient level of illuminance and the ability to regulate the light level. Always in relation to the task and the ambient light in the space, and thereby creating a pleasant and comfortable light environment. Research suggests, when giving the users some manual control possibilities, the satisfaction with the lighting conditions in general increases The users should be able to both increase and dim the light levels or completely turn it off. Thissuggests, if the lighting control system is designed to regulate the illuminance automatically, it should be provided some kind of manual override. This is supported by the findings in the surveys, where all countries in one way oranother find it important to provide the u

The integration of daylight and electric lighting, considering user satisfaction and energy savings potentially can contribute significantly to reduce energy demand for lighting, that represents 18% of global energy demands. This paper presents the work and first results of IEA SHC Task 61/EBC Annex 77 “Integrated Solutions for Daylighting and Electric Lighting: From component to user centered system efficiency”, a joint project activity between the Solar Heating and Cooling (SHC) and Energy in Buildings and Communities (EBC). The project deals with the idea that an integrated design approach for the whole system, combining daylighting, electric lighting, the associated lighting controls and the users’ interaction, can achieve higher energy saving than the simple energy-efficient design of single components. First results show the main experience from three completed case studies.

The integration of daylight and electric lighting, considering user satisfaction and energy savings potentially can contribute significantly to reduce energy demand for lighting, that represents 18% of global energy demands. This paper presents the work and first results of IEA SHC Task 61/EBC Annex 77 “Integrated Solutions for Daylighting and Electric Lighting: From component to user centered system efficiency”, a joint project activity between the Solar Heating and Cooling (SHC) and Energy in Buildings and Communities (EBC). The project deals with the idea that an integrated design approach for the whole system, combining daylighting, electric lighting, the associated lighting controls and the users’ interaction, can achieve higher energy saving than the simple energy-efficient design of single components. First results show the main experience from three completed case studies.