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• A computational model was developed to study the impact of optical and fluorescent properties on fluorescent cooling potential. • The relation between solar reflection and PL-effect as complementary optical heat rejecting mechanisms was studied. • The highest theoretical fluorescent cooling potential for visible and NIR-emitting fluorescent materials was estimated. Quantum dots (QDs) coatings have recently attracted attentions as novel nano-scale fluorescent cooling materials with adjustable thermo-optical properties for urban overheating mitigation application. In this paper, a mathematical method for the prediction of impact of optical and fluorescent properties (i.e. absorption edge wavelength (λ AE) and quantum yield (QY)) on fluorescent cooling indicators including re-emitted energy (Q PL), effective solar reflection (ESR), and PL-related surface temperature reduction was proposed. The experimental thermal evaluation testing on three PbS QDs sample with different fluorescent properties and their corresponding non-fluorescent samples was performed to assess the accuracy of the proposed predictive model and evaluate the impact of fluorescent/optical properties on their cooling potential. The validated model was then used to optimize the fluorescent cooling potential for QDs samples with different fluorescent/optical properties. According to the model results, surface temperature reduction potential through PL effect demonstrates its highest value for QDs with solar absorption and QY near to unity, and λ AE at around 1300 nm. QDs coatings with the optimal solar absorption, QY, and λ AE showed up to 35 °C lower surface temperature than their corresponding non-fluorescent reference sample in a typical sunny day in Sydney. The maximum fluorescence contribution (Effective solar reflection (ESR)- Solar reflection (R)) is also estimated to be 0.44 for the fluorescent material with optimal optical and fluorescent property. Results of this study will support the next phase of research on fluorescent cooling. [ABSTRACT FROM AUTHOR]

• A novel method to simulate multifunctional biomimetic adaptive facades is proposed. • Multifunctional adaptive facades can be simulated with script-based controls. • 600 iterations of a multifunctional shading and ventilating Bio-ABS is analysed. • PVC glazing achieves shading, and SMA springs trigger ventilation by openings. • An adaptive façade over a non-adaptable one improves thermal comfort by 18 to 37.1%. Biomimetic adaptive building skins (Bio-ABS), being adaptable to changing environmental conditions, can foster improved comfort and reduced energy demand. Bio-ABS are climate-adaptable façades, and biological functions inspire their design. Buildings often require multiple functions for improved environmental performance. Multifunctionality refers to hosting multiple triggered by diverse stimuli interdependently. The realisation of multifunctional Bio-ABS may be challenging due to difficult construction processes, expensive materials, and the complexity in their application. Thus, digital modelling and simulation of multifunctional Bio-ABS are important to predict their performance. This paper reviews the studies on simulating Bio-ABS, proposes a novel simulation framework for multifunctional Bio-ABS and demonstrates it through a parametric case study. Performance comparisons among twenty base-case scenarios and 600 iterations of shading and ventilating multifunctional Bio-ABS provides shading through photovoltachromic (PVC) glazing and ventilation through Shape Memory Alloy (SMA) springs triggered openings. It is multifunctional by changing its morphology and physiology due to photovoltachromic glazing triggered by solar irradiance and Shape Memory Alloys being triggered by temperature. The results show that Bio-ABS improves building performance when compared against non-adaptable façades, reaching 37.1% for 90% acceptability limits and 18% for 80% acceptability limits for adaptive thermal comfort in an educational building in the humid subtropical climate of Sydney. Australia. The main outcome and contribution of this study is a novel simulation framework to predict the performance of morphology and physiology changing multifunctional Bio-ABS. Future work may focus on prototyping and validated experiments to close the gap between theory and the real world. [ABSTRACT FROM AUTHOR]

• Daytime radiative cooling materials are studied in two cities with Urban Heat Island. • Contribution of wavelength band to the ability to achieve sub-ambient temperatures. • Materials studied under highly-insulated and highly-conductive conditions. • Material's behavior strongly depends on the location and the type of application. The objective of this paper is to present the potential of daytime radiative cooling materials as a strategy to mitigate the Urban Heat Island effect. To evaluate the cooling potential of daytime radiative cooling materials, 15 theoretical materials and seven existing materials were simulated: two radiative cooling materials, a coolmaterial, two white paints, a thermochromic paint and a construction material. The novelty of this study is that it shows that the optimal spectral characteristics of radiative cooling materials depending on the climate conditions and the type of application. A sensitivity analysis was performed to evaluate the impact of each wavelength emissivity on the ability to achieve sub-ambient radiative cooling. The sensitivity analysis comprised a total of 90 theoretical materials with 15 different wavelength combinations and 6 emissivity values. The heat transfer model, which includes conduction, convection, and radiation, was developed using a spectrally-selective sky model. Two conditions were considered: a very conductive surface and a highly insulated one. All the materials were simulated in two cities that suffer from the Urban Heat Island effect—Phoenix and Sydney. The mean surface temperature reduction achieved was 5.30 °C in Phoenix and 4.21 °C in Sydney. The results presented suggest that the type of application (active or passive) is a determinant factor in the design of radiative cooling materials. Modifying the spectra of the materials led to a substantial change in the cooling potential. A material that performs well in a dry climate as a passive solution could perform poorly as an active solution. [ABSTRACT FROM AUTHOR]

• A detailed assessment of energy performances of BIPV/T-DSF was performed. • Three types of PV glazing and three types of ventilation modes were assessed. • The model with a naturally-ventilated air cavity showed the lowest consumptions. • The façade with Perovskite cells has the highest conversion of solar radiation. • Both DSFs with natural and mechanical ventilation collect useful thermal energy. Being the interface between indoor and outdoor, building envelope significantly influences indoor heating and cooling loads and thus affects building energy consumption. This paper presents the results of numerical simulation for the performance prediction of building-integrated photovoltaic/thermal double-skin facade (BIPV/T-DSF). Different BIPV materials (amorphous silicon PV, dye-sensitized solar cell and Perovskite based solar cells) were considered as the exterior cladding of a North-facing facade of an office building located in Australia. The performance assessment involved the selection of three climates in Australia, represented by the cities of Darwin, Sydney and Canberra. The air cavity created between the outer skin and the inner one were alternatively assessed in the non-ventilated, naturally-ventilated and mechanically-ventilated modes of operation, while a full sensitivity analysis was performed in order to assess the influence of different design parameters, such as internal skin's thermal transmittance, cavity depth, ventilation louvres' opening ratio and cavity ventilation rate. By comparing the different operational modes and BIPV technologies, it was found that naturally-ventilated DSF integrating the Perovskite-based solar cell could be the optimal configuration achieving the highest savings. Total annual energy savings of 34.1%, 86% and 106% annual were reached respectively in Darwin, Sydney and Canberra, in comparison to conventional technologies. In addition, this façade technology could further reduce the building's heating and cooling loads by harvesting thermal energy generated within the air cavity. The study finally demonstrated that the harvested electrical and thermal energy from the façade could cover a significant share of building's energy consumption. [ABSTRACT FROM AUTHOR]