Double Glazing Research Articles

Optimization of Heat Reflective Triple Glazing Thickness Using the Artificial Fish Swarm Algorithm

Abstract. The significance of this research lies in its potential to improve energy efficiency in buildings, particularly in regions prone to high temperatures. By optimizing the thermal performance of heat-reflective glass, buildings can achieve better temperature regulation, leading to reduced dependency on air conditioning systems and lower energy costs. This research specifically targets the optimization of glass thickness, a critical factor influencing the overall effectiveness of heat-reflective glazing. The focus is on minimizing the transmitted light intensity for sunlight within the wavelength range of 300 to 2000 nm, which is vertically incident on the glass. The optimized glass thickness aims to maximize the thermal reflective properties while ensuring adequate natural light within indoor spaces. This study employs the Artificial Fish Swarm Algorithm to explore the optimal thickness of heat-reflective triple glazing. The effectiveness of this optimization method is assessed by comparing its results with experimental findings obtained through a systematic traversal of glazing thicknesses. The results highlight the potential of the Artificial Fish Swarm Algorithm to significantly enhance the thermal performance of heat-reflective glass, offering a practical solution for energy-efficient building design in hot climates.

Quantum Genetic Algorithm-Driven Optimization of Triple-Glazed Window Thickness for Enhanced Light Reduction

Abstract. Glass, a common construction material, generally lacks significant thermal properties. As technology rapidly advances, the demand for glass materials with superior heat preservation and thermal insulation capabilities increases, driven by the need to reduce building energy consumption. Multi-objective optimization problems, particularly in complex multilayered systems, require advanced numerical optimization algorithms. The quantum-inspired genetic algorithm (QIGA) offers advantages such as fast solving speed and high precision, utilizing quantum coding, variation, rotation gates, and crossing techniques. This study focuses on designing the optimal thickness of triple-layer glass to minimize sunlight penetration through windows, using QIGA to achieve this goal. The results demonstrate that triple glazing effectively reduces solar radiation entering a room, though different layer combinations lead to significant variations in total energy reduction. The study also emphasizes the importance of concurrent research in glass layer splicing technology, coating film techniques, and new glass materials to enhance overall performance. These findings contribute to the development of energy-efficient building materials that meet modern standards for thermal insulation and light control.

Optimized design and comparative analysis of double-glazed photovoltaic windows for enhanced light harvesting and energy efficiency in cold regions of China

This study investigates the daylighting performance and energy efficiency optimization strategies of double-glazed photovoltaic windows (DS-STPV) in cold regions of China. By conducting a comprehensive comparative analysis with traditional and energy-efficient window systems, this research aims to identify high-efficiency building solutions tailored to extreme climatic conditions. Amidst the escalating global energy demand and the pressing need for energy conservation and emission reduction, Building-Integrated Photovoltaic (BIPV) technology is increasingly recognized for its potential and value as a critical method for harnessing green energy. However, the widespread adoption of BIPV technology faces several challenges, including cost-effectiveness, conversion efficiency, system stability, and architectural aesthetic integration. Utilizing the T&A House from the 3rd International Solar Decathlon as an empirical case study, this research employs Ecotect and DesignBuilder simulation software to systematically evaluate the daylighting effect and energy performance of DS-STPV. The analysis considers various key design parameters, including photovoltaic cell coverage, window orientation, and window-to-wall ratio. Through refined modeling and multi-dimensional analysis, this study aims to identify the optimal design configurations of DS-STPV windows in cold regions, with the goal of simultaneously achieving superior natural lighting quality and significant building energy efficiency. The findings indicate that a south-facing DS-STPV window design with approximately 30% photovoltaic cell coverage and a window-to-wall ratio of 30% effectively balances daylighting requirements and energy efficiency in cold regions of China. This design strategy not only ensures an abundance of natural light in the room, but also significantly reduces the building’s energy consumption, proving the superior performance of DS-STPV windows in cold climates. In addition, the unique optical properties of DS-STPV windows reduce glare, further improving the overall quality of the indoor environment. In summary, this study provides a robust scientific foundation for the application of DS-STPV windows in cold regions, offering practical guidance and reference for optimizing energy efficiency and facilitating green transformation in future building design.

Design and assessment of an adapted absorber solar air collector tailored for sustainable drying applications

The design of a relevant solar air collector (SAC) is imperative to make the drying industries self-reliant and sustainable in terms of energy. However, the literature doesn’t describe the coherent design assessment of SAC, and its viability for a drying system provided the scale-up opportunity for commercial applications. Hence, the present work was devoted to estimating the heat load for a particular drying condition, a methodological understanding of SAC design, and an investigation of the performance of the newly developed solar collector. The essential design criteria were the moisture content of fresh and intended dried items, physical attributes of items, dryer capacity, preferred drying temperature, projected drying duration, required air speed (based on dryer type), and local climate (solar radiation, ambient temperature and relative humidity). The regular semi-hexagonal shape aluminium (Al) sheet was chosen to introduce air turbulence while maximizing the surface area available for heat transfer. The regular semi-hexagonal absorber was outfitted with helical springs to generate air turbulence and augment heat transfer. A double glazing (polycarbonate) of 5 mm apart was mounted to impede radiation heat loss. Three successive days of the experimental study showed that the average temperature increases of air passing through SAC were 36.02 °C, 37 °C, and 39.2 °C. The optimal tilt angle with the horizontal surface was found to be 35° in a south-facing direction for the month of January. The highest energy efficiency was found to be 40.5 %, while the lowest was found to be 24.73 %. The sustainability index of the SAC was found to be 1.02. The experimental results clearly demonstrate that the designed SAC was capable of supplying adequate heat energy (at the minimum of 155.86 W/hr.) to meet the necessary heat load (125.82 W/hr.) for agro-products drying at the designed capacity.

The Real-Time Detection of Defects in Nuclear Power Pipeline Thermal Insulation Glass Fiber by Deep-Learning

The Real-Time Detection of Defects in Nuclear Power Pipeline Thermal Insulation Glass Fiber by Deep-Learning

Experimental and Numerical Studies of Heat Transfer Through a Double-Glazed Window with Electric Heating of the Glass Surface

This paper presents experimental and theoretical studies of heat transfer through single- and double-glazed windows with electrical heating of the internal surfaces. Heating is achieved by applying a voltage to the low emissivity coating of the inner glass. A thermophysical model has been developed to simulate the heat transfer through these units, allowing us to determine their thermal characteristics. Experimental data are used to validate the numerical model. The resulting heat flux and temperature distributions on the external and internal surfaces of electrically heated double-glazed units are analysed. According to the results of experimental and numerical studies, it was found that the adopted electric heating scheme allows 83–85% of the heat to enter the room and 15–17% is removed to the outside. This makes it possible to increase the radiation component of the heat flow from the window to the room and improve the thermal comfort in the room. In general, this article shows that existing industrial windows with low-emissivity glass surface coating can be upgraded with simple and inexpensive modernisation, without compromising the main function of the window—efficient transmission of visible light—and create an additional (backup) heating device that can work effectively together with the existing heating system in the event of a sudden cold snap at low temperatures (below −20 °C), to prevent condensation of water vapour in the windows, and to prevent condensation on the surface of the window facade wall. Formally, a back-up (emergency) heating system is created in the room, which contributes to the energy sustainability of the building and therefore to energy security in general.

How can interventions of building renovation and household energy conversion effectively improve the physical and mental health outcomes? A systematic review and meta-analysis

Household energy efficiency measures can effectively reduce indoor air pollution and positively impact the health of residents, but there is no conclusive evidence on the effectiveness of different energy efficiency measures for various diseases. This study used systematic review and meta-analysis to research the effects of two interventions on residents’ physical and mental health: building renovation (heating, insulation, double-glazed windows and ventilation) and household energy conversion (stove upgrading and clean energy use). A total of 79 papers published between 1977 and 2023 were reviewed in this study, providing comprehensive meta-analytic evidence on the effectiveness of energy efficiency measures. The results show that household energy-saving measures have a minor but significant positive influence on residents’ physical and mental health, with the effect on mental health being larger than the impact on physical health. Stove upgrading is advantageous in respiratory and cardiovascular diseases; insulation can greatly reduce the risk of skin diseases; heating is beneficial in sensory and digestive diseases; and clean energy use can successfully mitigate integrative diseases. Furthermore, a combination of heating and insulation measures has the most favourable influence on mental health conditions such as depression, anxiety and social isolation. The study findings can help residents, policymakers and relevant organizations take appropriate interventions to promote residents’ physical and mental health.

Study of electrical strength and electrical resistance of cast microwires in glass insulation

The results of a comprehensive study of the electrical strength of glass insulation and the electrical resistance of cast microwires insulated with borosilicate glass in the temperature range from −60 to 155°C are presented.

Climate Change and Building Renovation: The Impact of Historical, Current, and Future Climatic Files on a School in Central Italy

Climate change significantly affects the operating environment of buildings. These changes impact both energy efficiency and occupants’ comfort and remain crucial even in building restoration, where design decisions typically rely on historical data, yet performance depends on anticipated future scenarios. The present work evaluates the impact of different climate datasets on dynamic energy simulations for an educational building in Central Italy, focusing on estimating heating demands across historical, current, and future climatic scenarios. The assessment considers both the building’s current state and potential energy-efficient retrofits. Initially, various meteorological datasets, including measured and model-generated data, are selected to predict key weather parameters. The analysis reveals the potential and limitations of regional climate models (RCMs) in estimating these variables, with the MM5 dataset emerging as the most reliable. Subsequently, the energy performance of the reference building and its vulnerability to climate change are assessed. Our results show significant differences in energy demand based on construction periods, with the oldest section consuming 29% to 54% more energy monthly than the newer sections. Moreover, using non-representative climatic files can lead to prediction errors of up to 199%. Finally, the building’s energy behaviour is analysed under future climate conditions by generating typical meteorological years (TMYs) for 2030, 2050, and 2070. This analysis evaluates the energy requirements for both existing and retrofitted building configurations. The findings confirm that retrofit interventions with high-performance insulation and upgraded windows significantly enhance the building’s energy efficiency and resilience to future climate conditions, leading to annual energy savings of 50% to 57%.

A Influência de Brises e Cortinas na Eficiência Energética de Edifícios de Escritório

The construction sector is responsible for a significant portion of energy consumption and greenhouse gas emissions. In this sense, it is extremely important that initiatives are developed to reduce the energy consumption of buildings, contributing to the sustainability of these buildings. Among the alternatives for reducing energy consumption is the possibility of inserting shading devices into building windows. In this context, this work aims to analyze the influence of the use of shading devices on windows of an office building model geographically located in Passo Fundo - RS. To this end, 24 computer simulations were carried out using the Energy Plus software in a model of an office building considering its windows without any shading device and, subsequently, with the installation of two different types of sun shades and curtains that act according to the internal temperature of the building. environment and with a pre-defined agenda. Single and double glazing were also tested. The results revealed positive influences of shading devices in the office building, reducing electrical energy consumption by up to 4.64% in relation to the reference case. Therefore, the use of sunshades and curtains can help reduce energy consumption in the building, maintaining the thermal comfort of the environment.

Noise reduction design of new residential buildings along urban roads-taking a residential district in Foshan as an example

Taking a residential district in Foshan along the city road as an example, the impact of urban road traffic noise on it is studied. Firstly, the data is monitored in the noise field, then three-dimensional simulation models of residential buildings and road distribution are established in Cadna/A software, and noise simulation prediction is carried out according to the actual situation and relevant norms and standards. The predicted noise values of the exterior surface of residential buildings are obtained, which has exceeded the permissible interior noise level for residential buildings. By comparing the application effects of noise reduction measures in buildings, the noise reduction design scheme of new residential buildings along urban roads is finally proposed: the sound insulation doors and windows that meet the requirements are adopted. After the completion of the house, the indoor background noise and the sound insulation performance of the doors and windows are measured. The measured results show that the selection of sound insulation doors and windows is suitable and the indoor noise environment meets the design requirements of noise reduction. The results are helpful to provide technical reference for the noise reduction design and renovation of other residential buildings along urban roads.

Sound insulation of partially open windows - alternative laboratory measurement methods

Sound insulation with partially open windows has had growing attention in recent years. In Denmark, this is primarily caused by the Danish Environmental Protection Agency's guideline from 2007 "Noise from roads", which introduces noise limits with open windows (opening area of 0.35 m2) for situations with a high traffic noise level. The sound insulation of traditional windows in open position have been measured in both the laboratory and external environment, and for certain setups too different results have been observed. To investigate the reasons behind the discrepancies, the traditionally reverberant source room of laboratory measurements was modified to a semi-anechoic room to remove reflections from unwanted reflections from room surfaces and to imitate the external environment during field measurements. Four different window types were tested as part of the research projects "Optimized measurement method for sound reduction of partially open windows part 1 and 2" (MetÅV and MetÅV2) in collaboration with four Danish window manufacturers. The primary focus of the project is to explore alternative laboratory methods to the traditional diffuse field method by studying reference cases from field measurements and taking into consideration different sound source positions and window geometry. This paper describes the results so far.

Application of Cadna/A software to the prediction of traffic noise on residential envelope sound insulation

The primary issue influencing residential structures' interior sound insulation environments is urban traffic noise. When choosing sound insulation for residential windows and doors, it is essential to consider the influence of road traffic noise. In conjunction with the examples, a three-dimensional simulation prediction model is created early on using Cadna/A software, and it is configured in accordance with the measured data of the road environmental noise to predict the sound pressure level of the outer surface of the residential building's enclosure structure at various locations and floors. This serves as a foundation for choosing the residential building's interior sound-insulated windows and doors as well as for the building's construction. In order to confirm that interior doors and windows are structurally sound-insulated, sound insulation measurements of typical residential sample buildings are made later in the building process.It offers some reference value for using Cadna/A in the assessment and forecasting of traffic noise's impact on the soundproofing of residential building envelopes.

A meta-analysis of the schematic design process of deep retrofit projects

Deep retrofits of the existing building stock will be necessary to meet global emissions reductions targets. One building archetype, low-rise MURBs have been neglected in terms of research and funding for deep retrofits. A meta-analysis was conducted that compares and contrasts the schematic design approach taken for six such buildings in British Columbia which are scheduled to undergo deep retrofits with the goal of reducing GHG emissions by 80%. The analysis showed that design teams had converged toward common solutions for each building while achieving the GHG reduction target. The recommended measures include electrification of space and domestic hot water heating, adding insulation through overcladding, air sealing, ventilators for each unit, and double pane windows. A life cycle cost analysis showed that the economic viability of deep retrofits were dependent on energy price forecasts, capital cost reductions through market forces and transformation, or incentives cover the non-monetizable co-benefits of deep retrofits such as improved resiliency to climate-change or reducing overheating and air quality risks. The meta-analysis can help to streamline the early-stage and schematic design process for such buildings, which is critical to increasing the retrofit rate. This process could be replicated for other building types and construction archetypes.

Enhancing building energy efficiency: Innovations in glazing systems utilizing solid-solid phase change materials

This study investigates the energy efficiency of a double-glazing window (DGW) integrating a solid–solid phase change material (SSPCM) with limited thickness, applied to the inner glass pane within the air gap. Numerical model, validated against experimental data, is developed using a finite volume method in ANSYS Fluent. In this model, the Discrete Ordinates (DO) model is applied to simulate radiation, while the enthalpy-porosity approach is used to capture the solidification and melting processes in the phase change material. With this model, the energy performance of the system is analyzed under various transient temperature values (10 to 30 °C) and ranges (1 to 5 °C) during the coldest and hottest days of the year, as well as during cloudy and sunny days in Montreal (Dfb), Vancouver (Cfb), and Miami (Aw). According to the obtained results in Montreal, the DGW-SSPCM system consistently saves energy under summer sunny conditions, with optimal performance when the SSPCM remains transparent. However, it incurs energy losses in cloudy days, where the energy lost is 2.3 times greater than the energy saved in sunny days. In Vancouver, the system shows consistent energy savings, particularly at Tc = 30 °C, with average savings of 20.5 kJ (23 %) under summer sunny conditions. The system is most beneficial in Vancouver, where winter energy savings in cloudy days (50.6 kJ) are 7.1 times greater than the losses in sunny days (7.1 kJ). In Miami, the system results in energy losses by 60 % and 5 % (at Tc = 30 °C) under both summer sunny and cloudy conditions, respectively, indicating unsuitability for its climate. During winter sunny conditions, all three cities experience energy losses, with Vancouver showing the lowest of 7.1 kJ (3 %) and Montreal the highest of 64.4 kJ (19 %) at Tc = 30 °C. In winter cloudy conditions, the system saves energy in all cities, with the highest savings in Miami of 54.5 kJ (26 %) at Tc = 30 °C. Overall, the SSPCM-DGW system has proven to be beneficial in Vancouver across various conditions in terms of energy and visual performance. These findings highlight the necessity of considering localized climate factors when designing and implementing energy-efficient glazing systems. Finally, the SSPCM-DGW system has provided complete visual clarity during office hours, making it more suitable for commercial buildings.

Highly insulated hydrogen powered vacuum gasochromic smart windows for energy-efficient buildings

Switchable active hydrogen powered gasochromic smart windows present an appealing option for energy-efficient building integration, offering two controllable transparencies between ON and OFF states compared to traditional windows. Implementing such glazing in cold-climate buildings requires minimizing the total heat transfer across the glazing, achievable through vacuum-insulated glazing resulting in the retrofitting to obtain energy efficient building. This study investigates the potential of vacuum gasochromic (VGC) windows to enhance the energy efficiency of buildings in diverse climatic conditions, focusing on London, UK, and New Delhi, India. Comparing traditional single-glazing and double-glazing windows with vacuum-gasochromic windows in terms of thermal performance, energy demand, and dynamic control over solar heat gain and visible light transmission are evaluated using advanced simulation techniques with SketchUp, OPTICS6, WINDOW 7.8 and EnergyPlus 9.6. Results reveal that vacuum gasochromic windows exhibit superior thermal insulation with significantly lower U-values of 1.559W/m2K, reducing heat transfer and energy demand for heating and cooling. Vacuum gasochromic opaque states demonstrate exceptional performance in minimizing energy transfer, making them the most energy-efficient option, especially in warm climates like New Delhi with 9544.4 kWh. Conversely, vacuum gasochromic transparent state shows promise in reducing heating demand in London's cold climate by 9.43 %, highlighting their adaptability. Moreover, vacuum gasochromic windows allow dynamic control over solar heat gain and visible light transmission, enabling occupants to adjust transparency based on weather conditions and preferences.

Local accommodation energy efficiency in Lisbon: a red flag for tourism, indoor thermal comfort, and energy renovation targets

Abstract Climate change affects all sectors of society, and tourism is no exception. Adaptation in this sector is challenging because of its vulnerability to rapid change and uncertainties of an environmental and political nature. Local accommodation (LA) (short-term rentals) plays a key role in the Portuguese economy and is, thus, potentially a key driver of increased energy efficiency and promoting buildings decarbonization, thereby contributing both to climate change adaptation and mitigation of this sector. However, there is limited research on energy efficiency and climate change resilience in the LA sector. To address this research gap, this study focuses on four civil parishes situated in the historic center of Lisbon, Portugal. Using a multidimensional approach and cross-sectoral datasets, we assessed the energy efficiency of LA in Lisbon and explored the cost of renovation measures. This analysis exposed poor energy performance in LA buildings and a low frequency of buildings with thermal insulation or double-glazed windows. Despite this, energy performance in the LA sector was comparatively better than in the residential sector. Additionally, LA s are equipped with more heating and cooling systems than the broader residential sector. This knowledge is relevant for researchers and policymakers, contributing to developing sustainable tourism approaches and reaching the objectives outlined in energy renovation policies.

Comprehensive Investigation of the Thermal Performance of an Electrically Heated Double-Glazed Window: A Theoretical and Experimental Approach

The thermal performance of windows is an important area of research to reduce the energy consumption of buildings and improve indoor comfort. The application of innovative glazing technologies can improve the energy performance of windows and transparent facades, resulting in significant energy savings. This paper presents research results on the energy performance of electrically heated windows. A comprehensive CFD and experimental analysis of the heat transfer processes in a window space depending on the size, power, and location of an electric heater was performed. The convective gas flows in the gas gaps and in the boundary layer were also analysed, and it is shown that a window with an electric heater can reduce the energy consumption of a room by 10–12%. This study is a pilot study to assess the feasibility and cost-effectiveness of electric local heating of a window or facade to minimise heat loss before full-scale implementation. The results of numerical modelling and experimental studies confirm the potential of the new technologies.

The role of passive, active, and operational parameters in the relationship between urban heat island effect (UHI) and building energy consumption

The energy performance of buildings located in urban areas is strongly influenced by the UHI phenomenon, which usually leads to higher cooling energy consumption and lower heating energy consumption. Despite the known effects of UHI on building energy consumption, there is a lack of detailed knowledge on the role of building design and operational parameters in determining the effects of UHI on building energy use. To address this knowledge gap, this study analyzes the impacts of UHI on annual, heating, and cooling energy consumption of 16 prototype buildings located in 16 climate zones in the United States. The objective is to determine the relative relevance of building types (e.g., residential, commercial, healthcare facilities etc.), occupancy parameters (e.g., occupancy schedule) and the Heating, Ventilation and Air Conditioning (HVAC) systems in governing the impact of UHI on the building energy use matrices. Additionally, the thermal properties of the building envelope were evaluated to determine their relative importance in mitigating the effects of UHI on building energy performance. We found that, among the studies building types, while the cooling energy use of restaurant and outpatient healthcare buildings was most affected by UHI (higher cooling energy demands), the outpatient healthcare buildings were most impacted by UHI in terms of their heating energy use (lower heating energy use). The selection of HVAC systems type was found to have negligible influence on the energy impacts of UHI. Lastly, with regard to the thermal properties of the building envelope, window insulation was noted to be the most influential thermal property, followed by roof and wall insulation. Also, the role of insulation as well as other thermal properties was higher in the context of UHI’s impact on heating energy consumption as compared to cooling energy consumption. Not only are the results of this study useful for urban planning purposes to determine the vulnerability of different buildings to UHI, but they also are beneficial to UHI-resilient building designs.

Optimization of microwave-produced coal-derived char insulation foam using response surface methodology

A new char-based insulation foam (CIF) is developed using coal-derived pyrolysis char (PC) and lignin, a paper and pulp industry byproduct. In this study, CIF is prepared by adopting the microwave method and Response Surface Methodology (RSM) is utilized to optimize predictions about the properties such as thermal conductivity, foam texture, compressive strength, and pore distribution of CIF. The three independent variables including percent char content, lignin/char ratio, and foaming agent/polyol ratio are considered in the RSM methodology. The face-centered central composite design is selected to obtain 17 test runs. Optimization of the predicted responses is performed to find the recipe considering a composite desirability function. Confirmatory test results show agreement between the predicted and observed values, with the percent error ranging from 0.00 % to 11.35 %, thereby confirming the accuracy of the prediction equations. The optimized CIF exhibits a thermal conductivity of 0.0633 W/m.K and a compressive strength of 695 kPa making it comparable to or better than traditional building insulation products such as fiber insulation, polymer composite, particle board, and ceramic glass foam. Therefore, this new CIF has the potential to be used as an energy-saving insulation material for building envelopes.