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Net zero-energy buildings have become one of the flagships in the path towards the decarbonisation of cities. Even though heating systems, especially in existing buildings, are currently the main consumer in many areas of the world, cooling needs are gaining relevance in several countries, and this is expected to be kept in the focus in the context of increasing temperatures, according to the climate projections identified by the IPCC. This has also additional implications on thermal comfort conditions (and, indirectly, on the derived health issues) in areas where no cooling systems are installed in residential buildings. This research work aims to evaluate the design of shading elements as a design strategy in the path towards net-zero residential buildings in diverse Colombian climates. A parametric analysis is developed, considering a combination of different shading solutions applied in residential buildings. Their effectiveness is evaluated in different climate zones in Colombia considering both the current climate data and future climate data expected according to the projections proposed by the IPCC. A reference building in Bucaramanga (Colombia) was selected for detailed monitoring, and the collected data were used to validate a simulation model developed in DesignBuilder. Almost 1000 alternative scenarios were established and parametrically evaluated, resulting from the combination of different shadings solutions, orientations and climate conditions. The results are evaluated considering two different approaches: cooling demand assuming a standard indoor temperature profile and indoor comfort when no cooling devices are used in the building, showing that some strategies, such as overhangs, involve significant improvements in terms of indoor thermal comfort and a reduction in cooling demand (reaching in some cases savings up to 30%) in the different climate conditions considered; as well, their effectiveness remains similar when future climate projections are considered. [ABSTRACT FROM AUTHOR]

This study investigates the application of dynamic window technologies in condominiums located in hot and humid climates, focusing on Thailand. The research integrates both passive and active window designs aimed at reducing energy consumption by maximizing natural ventilation and daylight, while minimizing heat gain. Dynamic windows, equipped with shading devices, automated controls, and stack-effect ventilation, can achieve significant energy savings by decreasing the need for air conditioning and artificial lighting. The energy performance was assessed through simulations based on Thailand's Building Energy Code (BEC), resulting in a potential reduction in energy consumption by 3.29 kWh/m2 annually or approximately 1.6% annually. Moreover, economic analysis showed that applying dynamic windows in condominiums could save up to 506.38 baht per room per year. The lifecycle cost analysis supports their long-term financial viability, achieving payback within 18.4 years and generating further net savings post-payback. The study concludes that dynamic windows are both scalable and sustainable, offering a viable solution for urban developments in tropical regions. [ABSTRACT FROM AUTHOR]

Tropical region such as Darwin has similar weather patterns throughout the year, thus creating higher energy demands in residential buildings. Typically, buildings consume about 40 per cent of the total energy consumption for indoor heating and cooling. Therefore, building envelopes are linked with design strategies such as the use of thermal energy storage and phase change materials (PCM) to minimize this energy consumption by storing a large amount of thermal energy. Primarily, PCMs are targeted by researchers for use in different components of buildings for thermal efficiency; thus, this study aimed to provide a suitable PCM to optimize indoor thermal comfort and minimize the cooling loads of residential buildings in tropical climates through simulation of a tropical climate building and provide optimum thickness for the selected material. Microencapsulated PCM mixed with gypsum in wallboards were used to reduce the cooling load of a building located in Darwin. The cooling load of the building was calculated using Revit software. A comparison of the cooling load of the building was carried out using PCM-incorporated wallboards of thicknesses of 0 cm, 1 cm and 2 cm in Energy Plus software. The total cooling load decreased by 1.1% when the 1-centimetre-thickness was applied to the wall, whereas a 1.5% reduction was obtained when a 2-centimetre-thick PCM layer was applied. Furthermore, the reduced cooling loads due to impregnation of the PCM-based gypsum wallboard gave reduced energy consumption. Ultimately, the 2-centimetre-thickness PCM-based gypsum wallboard gave a maximum reduction in cooling load with a 7.6% reduction in total site energy and 4.76% energy saving in USD/m2/year. [ABSTRACT FROM AUTHOR]

In Thailand, the delivery of adequate low-income housing has historically been overshadowed by politics with cost and quantity being prioritised over quality, comfort and resilience. In a country that experiences hot and humid temperatures throughout the year, buildings need to be adaptable to the climate to improve the thermal comfort of inhabitants. This research is focused on identifying areas for improving the thermal performance of these housing designs. Firstly, dynamic thermal simulations were run on a baseline model using the adaptive thermal comfort model CIBSE TM52 for assessment. The three criteria defined in CIBSE TM52 were used to assess the frequency and severity of overheating in the buildings. The internal temperature of the apartments was shown to exceed the thermal comfort threshold for these criteria throughout the year. The internal operating daily temperatures of the apartment remain high, ranging from a maximum of 38.5 °C to a minimum of 27.3 °C. Based on these findings, five criteria were selected to be analysed for sensitivity to obtain the key parameters that influence the thermal performance and to suggest possible areas for improvement. The computer software package Integrated Environmental Solutions--Virtual Environment (IES-VE) was used to perform building energy simulations. Once the baseline conditions were identified, the software packages SimLab2.2 and RStudio were used to carry out the sensitivity analysis. These results indicated that roof material and the presence of a balcony have the greatest influence on the system. Incorporating insulation into the roof reduced the mean number of days of overheating by 21.43%. Removing the balcony increased the number of days of overheating by 19.94% due to significant reductions in internal ventilation. [ABSTRACT FROM AUTHOR]

Opaque ventilated façades (OVFs) are increasingly gaining in importance in the design of sustainable buildings, given that they can lessen the building´s environmental impact. Opaque ventilated façades can reduce thermal gains in hot climate zones, improving the thermal comfort indoors, and reducing air conditioning demand. Nevertheless, the thermal behaviour of the opaque ventilated façade depends on the climatic conditions and the building´s specific design. This study analyses the effect of opaque ventilated façades in office buildings using 30 constructive configurations under eight tropical climate conditions. The study considers three options for the external layer of cladding (ceramic, stone, and aluminium composite material) and two configurations for the inner layer (plasterboard with mineral wool and ceramic). Simulations were carried out using the software tools TRanNsient SYstem Simulation program (TRNSYS) and TRNFlow. The model developed considers bioclimatic characteristics, including solar radiation and wind conditions for each climatic zone. The operating temperature was selected from within the range established by occupant comfort regulations. The findings suggest that it is possible to select the best office building opaque ventilated façade configuration for each of the specific climate conditions in Brazil. [ABSTRACT FROM AUTHOR]