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Shading systems improve building energy performance and occupant comfort by controlling glare, natural lighting, and solar gain. Integrating PV (photovoltaics) in shading systems opens new opportunities for BIPV (building integrated photovoltaics) on façades. A key problem of such systems is mutual shading among PV modules as it can lead to electrical mismatch losses and overheating effects. In this work, we present a new modeling framework, which couples parametric 3D with high-resolution electrical modeling of thin-film PV modules to simulate electric energy yield of geometrically complex PV applications. The developed method is able to predict the shading pattern for individual PV modules with high spatio-temporal resolution, which is of great importance for electrical system design. The methodology is applied to evaluate the performance of different dynamic BIPV shading system configurations, as well as its sensitivity to façade orientation and module arrangement. The analysis shows, that there is a trade-off between tracking performance and mutual shading of modules. Distance between modules is a critical parameter influencing the amount of mutual shading and hence limiting solar irradiation and electricity generation of PV shading systems using solar tracking. Planning of module string configuration, PV cell orientation, and location of bypass diodes according to partial shading conditions, reduces electrical mismatch losses and results in significantly higher electricity generation. The integration of parametric 3D and electrical modeling opens new possibilities for PV system design and dynamic control optimization. Though the analysis focuses on BIPV, the method is useful for the planning and operation of solar tracking systems in general. [ABSTRACT FROM AUTHOR]

Evaluating and optimising human comfort within the built environment is challenging due to the large number of physiological, psychological and environmental variables that affect occupant comfort preference. Human perception could be helpful to capture these disparate phenomena and interpreting their impact; the challenge is collecting spatially and temporally diverse subjective feedback in a scalable way. This paper presents a methodology to collect intensive longitudinal subjective feedback of comfort-based preference using micro ecological momentary assessments on a smartwatch platform. An experiment with 30 occupants over two weeks produced 4378 field-based surveys for thermal, noise, and acoustic preference. The occupants and the spaces in which they left feedback were then clustered according to these preference tendencies. These groups were used to create different feature sets with combinations of environmental and physiological variables, for use in a multi-class classification task. These classification models were trained on a feature set that was developed from time-series attributes, environmental and near-body sensors, heart rate, and the historical preferences of both the individual and the comfort group assigned. The most accurate model had multi-class classification F1 micro scores of 64%, 80% and 86% for thermal, light, and noise preference, respectively. The discussion outlines how these models can enhance comfort preference prediction when supplementing data from installed sensors. The approach presented prompts reflection on how the building analysis community evaluates, controls, and designs indoor environments through balancing the measurement of variables with occupant preferences in an intensive longitudinal way. [ABSTRACT FROM AUTHOR]

We present an expansion of the psychrometric chart for thermal comfort analysis using a new contour shading method that demonstrates a wider range of potential comfort conditions through the incorporation of additional comfort parameters. These extra dimensions include mean radiant temperature, air movement, metabolic rate, skin wettedness and the transitional behavior of occupants. The representations allow us to think outside the thermal comfort box with the use of innovative thermal design and comfort feedback for occupants. Building on the Olgyay bioclimatic chart, allowing architects to "Design with Climate", the new chart vizualizes a wide range of conditions that illustrate a physical basis for expanding comfort zones. It uses basic spatially invariant metrics employed in adaptive and other comfort models to allow "design with comfort" across all thermal comfort variables. The development of these methods has resulted in an open-source repository and web app available for designers and researchers to reproduce the charts and color-shading for their own projects. [ABSTRACT FROM AUTHOR]

Highlights • Analysis of energy savings of adaptive solar façade with multiple functionality scenarios. • Assessment via coupled ray tracing and R-C building energy model framework. • Potential for energy savings through offset of building energy consumption via solar power production or redistribution of incident solar radiation. • Energy demand and comfort optimization on a multi-building level. Abstract Actively controlled building facade technologies provide an intriguing method for building energy and comfort management as well as on-site electricity generation. Here, a novel concept is proposed which allows for energy and comfort management on a multi-building level by making use of sunlight redirection via adaptive reflective panels mounted on a building façade. Utilizing such a system to share solar radiation between building surfaces will improve utilization of the solar resource in urban settings, contributing to a reduction in waste energy and subsequently mitigating the urban heat island effect. The authors term this technology a reflective adaptive solar façade. A framework is presented that models and assesses the performance of such a system, consisting of a Resistance-Capacitance building energy model coupled to a Monte Carlo ray tracing simulation. This framework is then utilized to determine the contribution of such a system to building energy savings. The simulation framework is applied to cases of different receiver designs including concentrating photovoltaic receivers and indirect heating. The façade's novel abilities to redistribute sunlight between buildings open new pathways for intelligent urban design via efficient distribution of solar energy resources. [ABSTRACT FROM AUTHOR]