There is great potential for building performance optimization (BPO) in the early design stage, but there is still a lack of methods, algorithms, and tools to support the BPO process in this stage. ...Through a comprehensive review, this study identified three critical issues that affect the implementation of the BPO process in the early design stage: model integration, real-time performance analysis, and interactive optimization design. This study provides a systematic solution to these three critical issues. In terms of model integration, a feature-based and graph-based 3D building space recognition algorithm is proposed to automatically convert the computer-aided design (CAD model) into a computer-aided engineering model (CAE model). In terms of real-time performance analysis, a simplified physical method, an HPC-accelerated method, and an AI-based method are explored, and a real-time energy modeling module and a real-time daylighting analysis module are developed. In terms of the interactive optimization design, a preference-based multi-objective BPO design algorithm that can consider user preferences is proposed to make full use of the decision-making ability of humans and the computing power of machines and significantly improve the optimization efficiency and result satisfaction. Based on the systematic solution, a multi-objective BPO design software, MOOSAS, is developed. MOOSAS allows real-time performance feedback, dynamic parameter analysis, and interactive optimization, supporting the BPO process in the early design stage. The innovations of this study are as follows: first, this study proposes a systematic solution to the three critical issues of the BPO process, i.e., model integration, real-time performance analysis, and interactive optimization design; second, this study develops a multi-objective BPO design software (MOOSAS) for the early design stage.
•This study proposes a systematic solution to the three critical issues of the BPO process in the early design stage: model integration, real-time performance analysis, and interactive optimization design.•This study develops China's first multi-objective design software, MOOSAS, to support the BPO process in the early design stage.•The potential of MOOSAS is presented through multiple application scenarios: real-time building performance feedback, parameter analysis, and design recommendations.
This paper extends the applicability of emerging frameworks for evaluating the non-visual effects of light through the development of a novel area-based daylighting metric addressing goals of human ...circadian stimulus and entrainment in buildings. Procedures using annual, climate-based daylight modeling of eye-level light exposures are developed to analyze and map indoor environments in regard to spatial and seasonal changes in the availability of a circadian-effective daylight stimulus. Because the biological effects of light exposure are not instantaneous, a novel approach is developed to assess the duration of an effective stimulus on a daily basis, as well as the frequency an effective stimulus is present over the course of a year. Results can be used to identify and visually examine building zones where long-term occupancy may lead to disruption of the circadian system in the absence of supplemental electrical lighting capable of effective circadian stimulus. The metric and visualization techniques are implemented in a parametric, simulation-based workflow utilizing publicly available software tools. The workflow can be used to assess and differentiate the performance of various daylighting strategies during the design phases of a project, or to examine existing spaces. The applicability of the workflow is demonstrated using two example models: a portable school classroom, and a generic open-plan commercial office floor plate.
•A novel circadian daylight metric is presented.•A spatial classification system and visualization techniques are developed.•A simulation approach is demonstrated for informing design using circadian metrics.•The metric enables area-based summary of circadian effectiveness.
This paper proposes a performance-based design validation approach to study EnergyPlus for daylight harvesting capabilities. It considers EnergyPlus as a possible analytical tool to assist in design ...decisions, because it enables the rapid calculation of multicriteria analysis. The study has two main sections: first, it presents a sensitivity analysis of input parameters, such as wall reflectance, window size and position, visible transmittance of glazing, and room width. It uses useful daylighting illuminance (UDI) as the output parameter for analysis. Second, it presents a comparison of a hypothetical scenario for the design of a shading device to establish a comparison between a validated simulation tool and EnergyPlus considering a performance-based design process. The validation was performed against the Radiance simulation engine using direct and relative validation approaches. The geometric model for analysis consisted of an egg crate shading device with variations in the horizontal and vertical components. The output index, which was used as a decision-making parameter, was the occurrence frequency of hours within the UDI. The results showed that EnergyPlus classified solutions similarly to Radiance. The errors were within a 20% margin, and it was considered satisfactory for assisting in the search for low complexity facade design solutions.
∙The use of EnergyPlus for daylighting analysis in early design stages.∙Validation models for simplified architectural analysis tools in the context of performance-based-design∙Sensitivity analysis and comparative testing.∙Key limitations and guidelines to use EnergyPlus in less pragmatic daylighting analysis.
•Atrium is conducive to the natural lighting environment of underground commercial space.•1–3 square skylights, 5°-10° of profile inclination and 1:6 of skylight aspect ratio is ideal.•Highest energy ...savings rate is 1.2–1.3 times higher than the lowest.
Facing urban problems such as rapid urbanization, air pollution, heatwaves, and urban flooding, the underground space, as a significant urban composition, has demonstrated the unique potential. However, the properties of the lighting environment in underground spaces require the consumption of large amounts of energy. An optimal design strategy for natural daylighting in underground commercial spaces with high density, high usage, and high illumination demand can effectively achieve energy savings. In this study, the most common natural daylighting structure, the atrium, was selected. And the orthogonal analysis was used to simulate the lighting environment generated by four influencing factors (shape, number, profile inclination, and skylight aspect ratio) of underground commercial spaces. For an atrium space of two floors, the results show that the case of 1–3 square-shaped atriums, a profile inclination of 5°-10°, and a skylight aspect ratio of 1:6 comprised a suitable combination that can significantly reduce the electricity consumption. Different combinations of the four influencing factors resulted in different energy savings rates, and the highest energy savings rate was 1.2–1.3 times higher than the lowest. This study can be a valuable insight into the energy-saving design of the light environment in underground space.
The lighting load can be reduced either by improving the efficiency of artificial lighting or by supplementing daylight to the building interiors with Innovative Daylighting Systems (IDS). Fibre ...optic daylighting system is an up-and-coming IDS that utilises direct and diffused sunlight to illuminate deep-plan buildings without location and orientation constraints. The system can benefit both building occupants and owners by attaining comfort conditions, improving productivity, saving cost and contributing to sustainable goals. This paper aims to review and summarise previous studies on fibre-optic daylighting system by categorising it into five individual subsystems: light-carrying optical fibre cable, suitable collectors, diffusers, fibre–collector interface and fibre diffuser interface. Each subsystem is reviewed and analysed based on its material property, geometrical parameters, output measurements and performance. The advantages and shortcomings of the types of optical fibre cable are explained after investigating the material characteristics and transmission efficiency parameters. Collectors used in conjunction with fibre cable are classified and analysed based on the principle, mode of study, design specification, concentration achieved and output performance. Diffusers at the fibre end used for even distribution of light have been studied to compare the sizing, spacing and output spectral characteristics. Additionally, the collector–fibre and fibre–diffuser interfaces have been reviewed. We conclude the paper by identifying the shortcomings of the system and giving some pointers towards gap in the literature that needs to be addressed to improve the system's present state and aid its widespread implementation.
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•One of the first systematic reviews and classification of fibre optic daylighting systems and its components.•Performance evaluation of three major components, two interfaces, and the system by comparing the efficiency reported.•Identifies areas that need attention and further research.
•We optimized a complex classroom design for annual daylighting performance.•We evaluated daylighting with a new metric well-suited for optimization routines.•We assessed the performance of four ...optimization algorithms.•Two algorithms converged quickly but found inconsistent solutions.•Two algorithms converged slowly and consistently found near-optimal solutions.
We address the challenging problem of optimizing building design for daylighting performance to minimize lighting loads, which is one of the two largest sources of energy consumption in buildings, besides thermal loads. We present a methodology to optimize complex building design for daylighting performance that uses dynamic climate-based lighting simulations. We compare four optimization algorithms as implemented in GenOpt: Simplex Algorithm of Nelder and Mead with the Extension of O’Neill (SA), Hooke Jeeves (HJ), Particle Swarm Optimization using Inertia Weight (PSOIW), and a hybrid PSO Constriction/Hooke Jeeves (PSOC/HJ) algorithm. The results indicate that the design space region of optimum performance is typically found quickly by all algorithms, but converge is sometimes slow. SA and HJ typically reached convergence in fewer function evaluations than PSOIW and PSOC/HJ; however, they did not consistently find solutions close to the overall best solution found. PSOIW found the best overall solution and consistently found other solutions close to it, but always took longest to converge. PSOC/HJ reached convergence more quickly than PSOIW and consistently found solutions slightly below the overall best solution found. While our work presented here focused on optimizing for daylighting performance in isolation of thermal envelope loads, the best daylighting design had annual summed lighting and thermal loads 33% lower than the best design optimized for thermal performance without consideration for daylighting.
Traditional solar screens in Iran (called Moshabak) are architectural devices used mainly in hot-arid regions, with two interrelated functions: controlling the penetration of sunlight and gaze from ...outside. Consequently, Moshabak plays a significant role in veiling the interior from both and improving the quality of space. This research investigates the significance of aperture proportions for the lighting behaviour and transparency characteristics of Moshabak. The experiments are conducted in a typical residential room, under the sunny and clear sky of Kashan - a typical desert city in Iran. The study is divided into three stages and uses three kinds of Moshabak based on aperture proportions: horizontal, vertical, and square. Stage one of the research focuses on daylighting behaviour, stage two measures annual glare and stage three analyses transparency. For each type of Moshabak three different perforation percentages are used in order to better clarify the performance of different aperture proportions. The research findings show that aperture proportion has a significant impact on the performance of Moshabak. Moreover, Moshabak with horizontal apertures perform better than the rest, while Moshabak with vertical aperture proportions had the lowest performance in the three stages of the study.
Lighting is necessary for all kinds of buildings and consumes a large amount of electricity. Tubular daylighting devices (TDDs) can serve as an alternative, but they may also have thermal effects on ...the indoor environment, which has not been studied yet. In this paper, a lighting-heating coupled TDDs system was designed and built, to improve the use of TDDs for building energy savings and sustainability, where antimony tin oxide (ATO) nanofluids were introduced to absorb extra unexpected heat and then supply domestic hot water. Meanwhile, a new method was developed to calculate the annual amount of energy output of TDDs under different mass concentrations of ATO nanofluids. Results showed that the ATO nanofluids of 100 ppm can absorb ∼ 50% solar radiation coming along with more efficient visible lighting. Furthermore, in the case study in Beijing, TDDs with 100 ppm ATO nanofluids could generate over 10 tons of domestic hot water while saving 30.9 kWh of electricity for refrigeration, resulting in a ∼ 10% improvement on total energy-saving performance. This research work demonstrates the high potential of using the designed lighting-heating coupled TDDs system in buildings for both energy savings and daylighting benefits.
This paper presents a POE study integrated with physical lighting quantities in an open-plan office. The southwest-facing office has external overhangs and internal mechoshades as the solar controls. ...However, 65.9% of the participants in the office still complain about daylighting glare at their workstations. Aiming to improve indoor environmental quality, a renovated layout is constructed in a section of the office. The office results in two types of layouts, the original and renovated ones, in addition to three window heights. The research uses mixed methods to explore the environmental variations that influenced occupants' lighting experience and investigate the effectiveness of the renovated layout in terms of glare reduction. HDR image techniques are utilized for field measurements and calibration of a simulation model. The questionnaire generated based on the interviews with occupants is distributed to the office. The calibrated simulation model presents annual daylighting performance outside of data collection periods. The results show that taller windows, seating orientations towards windows, and adjacent to windows lead to more glare for occupants. Although replacing the original cubicle workstations with more open workstations allows more daylighting penetration and prolongs the annual glare duration in the renovated layout, more accessible outside views and flexible furniture designs increase occupants' tolerance of glare and satisfaction with daylighting environments. This research demonstrates the effectiveness of utilizing multiple methods to comprehensively assess daylighting qualities in open-plan offices. It also demonstrates the important role interior designs play in creating comfortable daylighting environments.
•Evaluate the daylighting quality in an open-plan office based on survey, measurement, and simulation.•Reveal the impact of three window heights and two interior layouts on occupants' daylighting experience.•Demonstrate the importance of interior designs regarding increasing occupants’ satisfaction with daylighting environments.
•A daylighting model and an energy simulation model of the vacuum PV glazing were developed.•The applicability and limitation of the vacuum PV glazing in different climates were investigated.•The ...vacuum PV glazing improves the energy performance of typical PV glazing.•The vacuum PV glazing can balance the daylighting availability and visual comfort.•The reversed and the reversible vacuum PV glazing can enhance the potential of the application.
Amorphous silicon-based semi-transparent photovoltaic windows can produce renewable electricity and offer a certain amount of natural daylight for occupants. However, it has a deficiency as the absorbed solar energy would be partially transferred into additional cooling demand in summer. In this respect, a novel semi-transparent photovoltaic vacuum glazing is proposed to improve energy performance. The selection of appropriate glazing of an energy-efficient building should take into consideration the specific climate conditions. The daylighting behaviour of the glazing will also affect the daylighting performance as well as the lighting consumption. In this paper, the thermal performance, daylighting performance and overall energy performance of the proposed vacuum PV glazing in different climate regions have been investigated. A daylighting model was conducted by DAYSIM to evaluate the annual daylighting performance. It was found that the vacuum PV glazing can balance daylighting availability and visual comfort by providing sufficient daylight in the anterior half of the room and reducing daylight glare to the minimum level. The energy simulation by EnergyPlus demonstrated that the vacuum PV glazing has the energy-saving potential up to 43.4%, 66.0%, 48.8%, and 35.0% in Harbin, Beijing, Wuhan and Hong Kong, respectively. However, the applications of the vacuum glazing lead to additional cooling consumption in the moderate climate zone, such as Kunming. The results advanced the understanding on the applicability and limitation of the vacuum PV glazing in different climate backgrounds. Furthermore, the reversed and the reversible vacuum PV glazing were proposed to enhance the adaptability. The results suggest that the reversible vacuum PV glazing can act energy response in a more efficient way and fully utilize the energy-saving potential of the integration of the PV glazing and the vacuum glazing.
