Daylighting Strategies Research Articles

The Non-Image-Forming Effects of Daylight: An Analysis for Design Practice Purposes

Daylight plays a crucial role in human health, and as research into its effects expands, it is essential for designers to estimate the non-image-forming impacts of various daylighting and lighting strategies. This allows them to create indoor environments that are both pleasant and comfortable. To support this, daylight measurements were taken in five Chinese cities, focusing on spectral power distribution, correlated color temperature, and illuminance. The study calculated the non-image-forming effects of daylight exposure using metrics like melanopic Equivalent Daylight Illuminance and Circadian Light. A key finding was the development of the action factor SAI, which estimates the potential non-image-forming effects of light in built environments. This factor serves as a proxy for understanding how non-image-forming effects relate to correlated color temperatures. Additionally, the research suggests the possibility of creating a time-variational daylighting and lighting strategy with four distinct periods of non-image-forming effects throughout a 24 h day. These insights could be valuable for architects and designers in optimizing indoor lighting systems.

Daylighting and energy performance optimization of anidolic ceiling systems for tropical office buildings

A simple window is often unable to ensure standard illumination to the deep parts of large office spaces, and advanced daylighting systems are necessary to ensure the level of interior illuminance. Anidolic ceiling systems are one of the less popular daylighting strategies designed to redirect and redistribute daylight deeper, which can reduce the demand for artificial lighting and energy use for lighting purposes. This study shows how a parametric approach can be applied to optimize the daylighting and energy performance of an anidolic ceiling system in a tropical climate. Multi-objective optimization (MOO) techniques were applied to combine different design variables to establish multiple design alternatives and find the optimal design by comparing their performances. A simulation study of an anidolic ceiling system was conducted with test models primarily developed by Rhinoceros and ClimateStudio, and optimization of performance metrics was conducted using Grasshopper and Octopus. Data exportation was done using the TT toolbox, while data analysis was done through mathematical and statistical analyses and cross-checked by Design Explorer. By incorporating an optimum anidolic ceiling system into the case office space, spatial daylight autonomy (sDA) increased 20.51 %∼68.18 %, annual sunlight exposure (ASE) decreased 15.83 %∼8.52 %, mean illuminance increased 221 lux–3027 lux and energy use intensity (EUI) reduced 189.3 kWh/(m2y)∼174 kWh/(m2y) for different configurations of test models. The results demonstrated a MOO methodology that successfully finds the optimum solutions for the anidolic ceiling systems in a deep plan office space to enhance daylighting and energy performance.

Optimizing Building Form for Daylight Access in Dense Urban Areas in the Early Stages of Design

The urgency to address climate change, the energy crisis, and indoor air quality underscores the importance of utilizing daylight as a renewable energy source in urban environments. This study delves into passive design strategies to facilitate access to sunlight and daylight within urban contexts and architectural designs, aggregating essential parameters identified in the existing literature to improve building forms for daylight accessibility. The study then develops a multi-scale, multi-objective framework integrating these passive strategies to optimize building performance in densely populated areas. Suitable approaches for incorporating daylighting at both building and urban scales are identified by examining existing passive form-finding strategies and rules of thumb. Given the implications for dense urban areas, floor area is used as an evaluation criterion, with energy use intensity (EUI) and carbon footprint serving as additional criteria in the optimization process through manual analyses and computer-based tools. By adopting a workflow that considers multiple objectives and parameters, this study aims to guide designers in integrating optimal daylighting strategies during the initial design phases.

Assessment of Daylighting Strategies in Selected Convention Centres for Improved Sustainability

The study aims to assess the extent to which daylighting strategies are implemented in selected convention centres. The objectives are to identify daylighting strategies utilized in selected convention centres, and evaluate their adequacy. The study focused on convention centres as they are commercial buildings that consume large amounts of energy. Three convention centres were conveniently selected at random in Lagos State, Nigeria due to the easy access for observation. The study used the mixed-method approach. 100 questionnaires were issued to respondents in each centre and 131 were retrieved and used for analysis. The data collected were descriptively analyzed using the Statistical Package for Social Sciences (SPSS), and the results were sorted from the highest to the lowest in terms of their mean item score (MIS), and presented in tables. The sizes and functions of the identified strategies in the case studies were analyzed in relation to standards, and the findings were discussed in relation to other researches. It was revealed that the selected convention centres did not utilize daylighting strategies effectively as they rely largely on artificial lighting. The findings further revealed that daylighting is not very well considered at the conceptualization stage of this building typology. The pieces of evidence show that as the elements in a space are considered, adequate daylight can enter that space and create the potential for energy savings in lighting. Further studies can be carried out in existing convention centres in other developing countries to explore the influence of daylighting on energy savings. This paper provides valuable information on acceptable daylighting strategies based on the observations made which could be incorporated in convention centres from the design stage, and insight into measuring the adequacy of daylighting strategies in convention centres in comparison with other researchers’ findings as discussed below.

Sensitivity Analysis and Multi-Objective Optimization of Skylight Design in the Early Design Stage

Building geometry design decisions are important for energy efficiency and daylight performance. Sensitivity analysis, coupled with optimization, is an important approach to investigate and optimize building geometry in the early design stage. Incorporating skylights is an important daylighting strategy in commercial buildings; however, skylight-to-floor ratio (SFR) is often the only design variable evaluated in precedent studies. More design variables related to skylight geometry, clerestory geometry, skylight material, and building geometry need to be evaluated. This study investigates the skylight design of a 2000-square-meter commercial building. Eighteen design variables are evaluated according to their influence on building energy and daylight performance. One-at-a-time (OAT), linear regression, and Morris sensitivity analysis approaches are utilized to identify the most influential variables. Seven of the twelve building geometry variables and two of the six building material variables are considered as important. Then, a multi-objective optimization with genetic algorithms is processed to find out the optimal design solution. The three objectives are energy use intensity (EUI), daylight autonomy (DA), and daylight uniformity (DU). After the optimization, five candidate design options are picked from the Pareto front. Discussions are made on the features of these designs, and one design is selected as the optimal solution.

Glare analysis of an integral daylighting and lighting control strategy for offices

Complex Fenestration Systems (CFSs) can significantly impact both the visual and non-visual daylight effects on the occupants as well as the energy performance of buildings. To ensure that those impacts improve the overall situation, proper control algorithms are required if the CFS can be operated. The state of the CFS directly and immediately effects the indoor lighting situation. The thermal condition of the building is usually strongly but not directly influenced by the condition of the façade system due to thermal capacities.In this study an experimental integral control strategy, called Integrated Lighting Module (ILM) is investigated in terms of it’s glare prevention capabilities and compared to a cut-off- and a simple rule based control logic. The ILM is an autonomous software package capable to run on building management hardware to control façade systems and artificial lighting in real buildings in an energetically optimised way. The adaptive sampling algorithm raytraverse is employed to calculate Daylight Glare Probability (DGP) values, which are used as a benchmark for the control strategy comparison. The other aspect of this comparison is the opening of the façade, which is evaluated as statistics how often each possible façade state is selected by each control strategy.

Daylight Analysis in Terms of Building Direction and One-Way Roof

The location of the buildings in the residential area is very important in protecting or benefiting from sunlight. The dynamic structure of the sun, which constantly changes according to time and seasons, directly affects the building's architecture and urban formation. Ignoring the sun's use of the structures during the construction of the buildings can cause significant disturbances to the residents. Daylight strategies, which are also influenced by climate, depend on the availability of natural light, determined by the latitude of the building site and the instantaneous conditions around the building. High latitudes have different summer and winter conditions, with lower daylight levels in winter. At these latitudes, designers often aim to maximize daylight penetration in buildings. In the tropics, where daylight levels are high throughout the year, the design emphasis is often on preventing overheating by limiting the amount of sunlight entering the building. Daylight availability depends not only on latitude, but also on the orientation of a building, and each facade and material of the building requires a different design importance. Therefore, daylight and architectural design strategies are two inseparable phenomena. In this respect, examining traditional architecture and successful natural lighting designs in the past is very useful for understanding climate-balanced building design. For this purpose, determining the roof slope according to the sun angle in architectural structures by calculating according to the location provides efficiency in many issues from energy efficiency to human health.

Sustainable performance in public buildings supported by daylighting technology

Many towns and villages around the world have implemented new technologies within lighting recently because there is an urgent need to save electricity, operational and maintenance costs. Taking into account recent global issues such as global warming, climate change, COVID-19 and increasing electricity bills, many countries have changed their plans for saving electricity by implementing more efficient, sustainable strategies. A global perspective and classification of the main lighting aspects necessary to implement sustainable daylight performance in public buildings is presented here. Qualitative research methodology is utilized in this article in order to clarify how daylighting strategies in public buildings contribute to the achievement of sustainable daylight performance. Objectives for achieving integrated pathways for sustainable development are detailed, related to natural lighting environment improvement, architecture, style and human health, and supported by a balanced organizational structure in order to achieve zero-energy buildings. The article also emphasizes the significance for the future of ensuring acceptable lighting through best lighting practices, providing advice through optimal lighting strategies in an efficient, realistic and responsible way. This lighting approach will serve to help in achieving nearly zero-energy buildings as a form of sustainably designed buildings. Finally, the article summarizes the most appropriate techniques for improving the daylight performance in public buildings, and an optimized human eyesight system is presented, based on the visual economy as a model of sustainability.

Students’ Perception of the Natural Daylighting in Higher Education Design Studios

An energy-efficient and environmentally friendly building are key to establishing green buildings. Both key concepts are predominantly significant in today's sustainable development concept. Higher education institutions have started their green and sustainable campaign to meet the government's initiative to reduce energy consumption. Energy consumption is increasing annually, whereby for the past 10 years, energy usage in government buildings has increased from 50,000 GW to 109,000 GW per year. The electricity bills increased due to the extensive use of artificial light. Artificial lighting is used extensively during the daytime in higher education buildings due to poor passive daylighting strategies in many buildings. Therefore, this paper intends to present the findings of a comprehensive and systematic analysis of students’ perceptions of natural daylight in design studios in higher education buildings. Survey-based investigations were conducted to analyse the student's perception of natural daylight. 149 questionnaires were distributed to Interior Design students from higher educational institutions. The data is being analysed using statistical analysis with the use of SPSS as the tool for analysis. The research found that the respondents prefer brighter natural daylight to artificial lighting in the studio. However, their design studio receives a high glare and thermal heat. The high glare and thermal heat subsequently made the respondents feel inconvenienced and uncomfortable due to glare and heat gain. As this paper only provides students' perceptions about natural daylight in the design studio, further study is needed to identify types of daylight strategies used in the design studio.

An Analysis of Day-Lighting Quality of an Architectural Design Studio: A Case Study on a Design Studio of Chattogram

Day-lighting is correlated to the optimum output of the specific purpose of any interior space for which the building infrastructure is constructed. When it comes about designing a studio for student of architecture, it becomes more important because of its connection to creative work. The close link between daylight and productivity is evident from many literatures. However, due to the availability of electricity and provision of different artificial lighting, natural lighting strategies became negligible by designers. But with the rising concern of achieving sustainability, designers now try to revitalize day-lighting strategies in building construction. For this purpose, we need to evaluate the current situation of a space and find out the problem. This paper focuses to evaluate the current day-lighting quality of an architecture studio at two different days: one is typical clear sky day and another is overcast sky day. The finding indicates that adequate windows are provided in this studio which causes it illuminate within range during typical clear sky days but artificial lighting is required when the sky is over casted. Key Words: lighting, studio, illuminance level, window

Daylight performance analysis of a residential building in a tropical climate

The present study investigates the effects of visible light transmittance in glazing and window-to-wall ratios on the ground floor daylighting performance in a two-storey residential building in a warm-humid climate. The metrics used to optimize daylighting performance with minimal glare are useful daylight illuminance, annual sunlight exposure, and spatial daylight autonomy. The daylighting performance of a residential building is assessed by empirical method and Design-Builder simulation, focusing on overcast sky situations. The useful daylight illuminance is the primary metric for analysing the amount of daylight throughout the year. Annual sunlight exposure and spatial daylight autonomy complement useful daylight illuminance in evaluating the daylighting performance. A window-to-wall ratio of 16%, a visible light transmittance of 0.62, and a glare of 0.52 can meet the daylighting requirements and standards. A design change in the window position helps to obtain annual sunlight exposure within 10% while maintaining high daylighting performance. When installed in the upper position of the wall with a higher sill and lintel height, glazing with a window-to-wall ratio of 16% and a visible light transmittance of 0.62 functions well without creating glare. The significant findings benefit all stakeholders in improving daylighting strategies in tropical climates and satisfying building standards.

Lighting Energy Reduction by Optimizing Daylight while Maintaining Cooling Load in Tropical Educational Building, Depok, Indonesia

This study aims to reduce the lighting energy consumption in educational buildings while avoiding an increase in cooling load. The Faculty of Engineering building in Universitas Indonesia, Depok, West Java, Indonesia is used as a case study. Daylight optimization can have an impact on lighting energy, which is the largest energy consumer in educational buildings. However, given Indonesia’s tropical climate, daylight leading to heat gain is a concern. Current passive design interventions for controlling daylight and heat gain include light shelves, clerestories, and glazing materials. Daylighting performance is simulated using DIALux software. Results of each intervention are analyzed quantitatively and qualitatively by theories and parameters, namely illuminance level, light uniformity, and overall thermal transfer value (OTTV). Light shelves result in increased uniformity and lower OTTV. Clerestories result in increased average illuminance but higher OTTV. Active intervention with a dimming and grouping system is applied after daylight increases. The combination of passive design interventions and active dimming of electric lights reduces lighting energy with the same OTTV as existing. This study recommends the use of passive and active daylighting strategies considering their effect on the cooling load of buildings.

Technology Interventions of Daylight for Deep Plan Building

Abstract: Daylight is important for buildings because it provides numerous benefits to the occupants and the building. Firstly, natural light is essential for visual comfort and productivity. Secondly, daylight is a source of energy and reduces the reliance on artificial lighting, which can lower energy costs and carbon emissions. Moreover, daylighting has been shown to positively impact human health and wellbeing by reducing stress and improving mood. However, deep plan buildings fail to receive natural light which hinders the productivity as well as the aesthetics of the building. This paper explores the importance of daylight in deep plan buildings, where spaces are located further from the perimeter walls and rely heavily on artificial lighting. Daylight has a significant impact on the quality of indoor environments, including visual comfort, energy efficiency, and occupant health and wellbeing. However, designing for daylight in deep plan buildings requires a specific set of considerations and strategies. The paper discusses these strategies, including the use of different technologies for introducing daylight in such buildings and presents case studies of successful daylighting in the same. The paper concludes that incorporating daylighting strategies in deep plan buildings is crucial to creating healthy and sustainable indoor environments.

Zero Energy Building Approach in Design of Biohydrogen Research Centre

The utilisation of natural energy not only can reduce energy consumption in buildings but also can lower carbon emissions from the use of fossil fuel energy for building services. It is believed that with appropriate design and a good attitude of building users, the role of renewable energy in reducing carbon emissions will be maximised. This study proposed the implementation of Zero Energy Buildings (ZEB) concept in the initial stage of building design by considering buildings’ form and façade design in relation to daylighting, natural ventilation and thermal design of buildings, and photovoltaic placement to save energy and to produce electrical energy in the designed building. In this study, ZEB Concept is treated as a secondary consideration in producing the architectural design for Biohydrogen Research Centre. The primary design generator is based on the philosophy of chemical bonds form representing biohydrogen chemical bonds. For a successful implementation of the ZEB concept in the Biohydrogen Research Centre design, both active and passive means are utilised in the building design. For passive means, daylighting and natural ventilation strategies were applied. While for active means, photovoltaic panels were employed as the primary electrical energy generation. Energy demand scenarios were predicted and calculated by the amount of energy used for lighting, air conditioning, and other appliances in the building. The total area needed for photovoltaic installation was obtained by balancing the energy demand prediction with the expected energy generation. The resulting design showed a promising outcome where the building is expected to achieve surplus energy with a total of 845,595.5 kWh electricity per year.

Analysis of Palu City’s Readiness Level Assessment Towards Adipura (case study: Siranindi Village)

The utilisation of natural energy not only can reduce energy consumption in buildings but also can lower carbon emissions from the use of fossil fuel energy for building services. It is believed that with appropriate design and a good attitude of building users, the role of renewable energy in reducing carbon emissions will be maximised. This study proposed the implementation of Zero Energy Buildings (ZEB) concept in the initial stage of building design by considering buildings’ form and façade design in relation to daylighting, natural ventilation and thermal design of buildings, and photovoltaic placement to save energy and to produce electrical energy in the designed building. In this study, ZEB Concept is treated as a secondary consideration in producing the architectural design for Biohydrogen Research Centre. The primary design generator is based on the philosophy of chemical bonds form representing biohydrogen chemical bonds. For a successful implementation of the ZEB concept in the Biohydrogen Research Centre design, both active and passive means are utilised in the building design. For passive means, daylighting and natural ventilation strategies were applied. While for active means, photovoltaic panels were employed as the primary electrical energy generation. Energy demand scenarios were predicted and calculated by the amount of energy used for lighting, air conditioning, and other appliances in the building. The total area needed for photovoltaic installation was obtained by balancing the energy demand prediction with the expected energy generation. The resulting design showed a promising outcome where the building is expected to achieve surplus energy with a total of 845,595.5 kWh electricity per year.

Exploring the environmental performance of liquid glass coating using Sol-Gel technology and responsive Venetian blinds in the tropics

The dynamic nature of tropical skies presents challenges for the built environment due to the momentous fluctuations and instability in solar irradiance and illuminance levels that cause limitations in responding to the needs of the indoor environment. The study aims to investigate the performance of daylighting strategies using liquid glass coating and responsive Venetian blinds in an office building in the tropics. The objective of this study is to systematically examine the impacts of proposed strategies on indoor environmental conditions. The study was experimentally investigated by utilising field measurements in full-scale cellular offices in a real environment and simulation using Radiance. The results indicated that responsive Venetian blinds provided steady daylight levels between 375 lx and 588 lx in the centre of the room, while a further integration with liquid glass coating provided a glare control with a maximum of 33.71% (Imperceptible) using Daylight Glare Probability. The indoor air temperature was reduced by 3.42 °C with liquid glass coating and 2.85 °C with responsive Venetian blinds. The outputs of assessing the performance of static and responsive strategies demonstrated new findings that are significant to developing these strategies in the tropics. • Static and responsive daylighting strategies were experimentally investigated. • The tested strategies provided effective solutions to control daylight levels. • The proposed daylighting systems improved thermal conditions. • The integrated daylighting system presented a responsive environmental strategy.

Investigation of Architects’ Awareness of Green Building Technologies in Lagos Metropolis

There is a growing concern about the negative impacts of buildings on the environment and the need to reduce them. Several studies have identified the relevance of green building strategies in this regard. Architects play vital roles throughout the lifespan of a building, from its conception to its demolition or conversion to other uses. It is in the light of this that this study examined the degree to which architects in the Lagos metropolis are aware of green building technologies. The objectives of the study included identification of the socio-economic characteristics of architects in the study area; investigation of their level of awareness of green building technologies; and to ascertain implementation of green building technologies in building projects by architects in the study area. A structured questionnaire was used to collect data from a sample consisting of 296 registered architects in the study area. The data obtained from this research was analyzed using the Statistical Product for Services and Solutions (SPSS). The findings revealed that architects in the Lagos metropolis have a general understanding of green building technologies but however, they have not implemented many of the technologies in their building projects. Ranking of level of awareness of the technologies investigated showed that architects in the study area were most aware of solar energy systems and least aware of energy efficient windows. Similarly, ranking of implementation of the technologies revealed that daylighting strategies were mostly used while biofuel systems were least used by architects in the study area. The study also showed that the major factor inhibiting architects from implementing green building technologies was clients’ resistance. Based on these findings, the paper recommends an intensive awareness drive to increase clients’ knowledge of the enormous benefits of green building technologies over conventional technologies.

THE ARCHITECTS’ AND LANDSCAPE ARCHITECTS’ VIEWS ON THE DESIGN AND PLANNING OF THE HOSPITAL COURTYARD GARDENS (HCG) IN MALAYSIA

This paper presents the architects' and landscape architects' point of views on their original design intentions in designing and planning hospital courtyard gardens (HCGs) in Malaysia. Following a field observation, a semi-structured interview with two architects and two landscape architects was conducted. Additionally, the architectural design briefs for three selected Malaysian hospitals were obtained as secondary data for this study. The results revealed that the intended common design pointed out by the architects includes: i) Daylighting strategy; ii) Ventilation strategy; iii) Access to nature; and iv) Point of orientation. Landscape architects, on the other hand, are concerned with: i) Forest-like garden concept; ii) Natural and organic form instead of aesthetic appearance; iii) An escape place for relieving stress and; iv) A hang-out space for socialisation. This paper contributes to the understanding of how designers would think and determine the architectural plan and landscape design in achieving an optimal HCG design to meet the needs of the intended users.

STRATEGIES IN IMPROVING THE BUILDING EFFICIENCY AND DAYLIGHTING: A CASE STUDY OF GREEN BUILDING

Malaysia is one of the rising countries with the highest energy consumption rate, which is attributable to strong economic development in the residential and commercial sectors that consume approximately half of the total electricity generated. Several criteria have been implemented in Malaysia to develop efficient building design, such as the Green Building Index (GBI) and Passive Daylighting Strategies. The study aims to investigate passive daylighting solutions for different building orientations and facade materials to measure energy efficiency through building designs. Buildings are a variable that contributes to growing energy consumption resulting from population increase and climate change. The building facade is a factor that could control the indoor environment, which affects the energy consumption in buildings. A case study determined the elements that maintain building efficiency and electric savings by examining two buildings certified by the Green Building Platinum and the Ministry of Finance (MoF). Low consideration of Passive Daylighting Strategies in building designs allows direct sunshine and increases the use of air conditioning to maintain the room at a comfortable temperature.

Determination of Design Solutions to Overcome the Daylighting Design Failure Observed in Existing Educational Building

Malaysia is blessed with abundant natural light throughout the year. However, as buildings absorb heat from it, the amount of energy required for cooling purposes increases, which is one of the causes of electricity consumption. This research focused on investigating daylight level with a variety of case study classroom characteristics that contribute to daylighting design failure factors. Hence, indoor and outdoor daylight levels were measured for five (5) days in each of the classrooms through field measurement method. The observation wasconducted simultaneously with the field measurement to assess the obstacles to implementing efficient daylighting strategies in the classrooms. The results show that the daylight performance for all of the case study classrooms was not withinthe prescribed suitable range as specified in MS1525 (2019). The classroom design is insufficient to manage daylight in classrooms, which is the most likely reason for the poor illuminance level results. Furthermore, the amount and performanceof daylight in the classroom are influenced by the classroom's specificdesign. The main factors leadingto design failures, according to theobservation analysis are poor classrooms orientation, double-loaded buildings with single-loaded windows, small glazing areas, low window placement, inappropriate glazing properties, and low light reflectance value. Based on the failure criteria stated, the best practices of classroom daylighting design were found.Furthermore, this study makes a few recommendations to increase the daylight value in all classrooms. This researchidentified problems that impact low daylight performance in educational buildingsand should be used to raise awareness of the benefits of daylight for occupants.