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Shadow effect among buildings has great impacts on the building energy consumption and the performance of building photovoltaic, and calculating shadows on building surfaces in urban building energy modeling (UBEM) faces challenges of inefficiency, especially for dense urban areas. In this study, a novel shadow calculation approach based on sunlight channel is proposed that can streamline the surrounding environment and accelerate the shadow calculation process. The sunlight-channel algorithm can further accelerate the shadow calculation process by dynamically predetermining the shading surfaces according to the actual solar position. In a real urban context, the proposed approach can accelerate the computation process by over 10 times over the baseline and over 34 times over the non-accelerated method, with a mean absolute percentage error (MAPE) of 1.13% for the total solar radiation. The proposed approach copes well with both large-scale urban models and the complexity of building structures, particularly for urban models with complex changes in building heights. This approach can significantly enhance the computational efficiency in complex urban environments, facilitating an accurate and rapid analysis of the energy consumption and solar potential of buildings in dense cities. • Sunlight channel algorithm was proposed to screen the shading surfaces dynamically. • A rapid method for shadow calculation for complex urban environments was proposed. • 13 neighborhoods with different spatial scale and height variation were compared. • Accelerate by over 34 times over the non-accelerated method, with 98.8% accuracy. [ABSTRACT FROM AUTHOR]

• Unscheduled simulation of the occupant behaviour in buildings. • Simulation of individual occupant behaviour by the agent-based modelling. • Support for the personalising of the designed building space. • Possibility to investigate individuals comfort during building design phase. Simulation of occupant behaviour (OB) in buildings is a challenging task. Available software uses a broad spectrum of tools that try to reproduce the patterns of human activity. From building energy perspective, the main emphasis in research has been focused on discovering behaviour directly related to energy. In recent years, more attention has been given to simulating occupant actions that are indirectly influencing building energy use. In most of the cases, this is achieved with the use of agent-based modelling which allows describing occupant actions on a room level. According to the existing methodologies review, it is a proper step, but to include occupant behaviour in energy simulations, spatial and temporal resolution of the occupant behaviour model must be improved. Addressing this issue requires the development of a comprehensive model supported by numerous modules that would cover various significant occupant actions. This paper focuses on the development of the high-resolution, data-driven movement engine of occupants. It is one of the fundamental modules necessary to simulate occupant behaviour with high granularity. Once the model is developed within its essential functionalities, it will deliver a bottom-up model capable of testing various energy use strategies. It will allow for testing different heat, ventilation and air conditioning solutions and the responses provided by simulated occupants. The data used to develop this module was obtained thru in-situ measurements, with the use of depth registration. Information obtained from experiments is similar to previous research, but it also extends the investigation scope with an additional transition-based variable. [ABSTRACT FROM AUTHOR]

• A built-in numerical method of radiative cooling in building simulation is raised. • Detailed experimental validation of the integration method is performed. • Energy saving of radiative cooling in a strip mall in six climates is analyzed. • A generalized and easily-usable simulation tool with built-in LRSIM is provided. Besides highly reflecting solar energy, the spectrum-selective radiative cooling materials (RCMs) dissipate heat to outer space especially through the atmospheric window (e.g., 8–13 μm) and achieve sub-ambient temperature under direct sunlight. Not only potentially contributing to Earth's heat rebalance, the daytime radiative cooling technology but also presents promising applications to building facades as a passive 'zero-energy' cooling method. Although there has been a large amount of radiative cooling materials developed recently due to the wavelength scale photonic material design, the wide application of radiative cooling materials to buildings faces challenges, including the barriers of scalable manufacturing and the lack of industry acceptable simulation tools for designers and engineers. Deliberating the major impacting factors such as moisture variation in atmosphere, this study designed a systematic strategy of incorporating spectrum-selective radiative cooling with whole-building performance simulation by developing a new long-wavelength radiation spectrum integral module (LRSIM) suitable for being built into the state-space model, like the DeST tool. Reduced-scale controllable experiments have validated the accuracy of LRSIM, giving < 3% deviation for the spectrum-based long-wavelength radiation calculation. Subsequently, experimental results from full-scale model houses were utilized to further validate the DeST tool embedded with LRSIM for building application of spectrum-selective radiative cooling materials. Indoor air temperature deviation < 1 °C was observed between the simulated and measured data, indicating the compelling prediction power of the integrated tool for radiative cooling modeling. Simulation analysis to a single-story commercial building at six locations around the world has shown energy-saving potential of 14–42% for an example radiative cooling material. Different from other customized plug-in integration, the experimentally validated DeST with built-in LRSIM will provide architecture designers and application engineers a general-purpose and easily-usable tool for promoting adoption of radiative cooling technology in buildings. [ABSTRACT FROM AUTHOR]