Triple-glazed Windows Research Articles

Energy Transmission Optimization in Multilayer Glass Models Using Particle Swarm Optimization

The intensification of global climate change and rising temperatures have underscored the need for energy-efficient building designs, particularly in southern China. This study proposes a particle swarm optimization (PSO) approach to optimize the thickness of triple-glazed windows (L1, L2, L3) to minimize sunlight transmission energy within the wavelength range of 300-2000 nm. A multilayer glass model was constructed, accounting for light transmission, reflection, and absorption properties. By simulating various thickness combinations, the transmitted energy was calculated across the wavelength spectrum. The PSO algorithm was then employed to search for the optimal thickness configuration that minimizes the total transmitted sunlight energy. Experimental results indicate that the proposed method significantly reduces indoor sunlight transmission compared to traditional design methods, enhancing both energy efficiency and occupant comfort. The findings highlight the importance of optimizing glass thickness and material selection in window design, balancing light transmission and shading to suit specific architectural needs. Additionally, this study underscores the impact of PSO parameters on convergence and solution diversity, suggesting further refinements for practical applications. The approach provides a scientific basis for building energy-saving designs and can be adapted to various climatic conditions and material specifications. Future work should focus on incorporating weather variations and expanding model complexity to enhance the algorithm's applicability in real-world scenarios.

Study the Thermal Performance of a PCM Layer-Filled Triple Glazed Window under Iraqi Climate Conditions

Study the Thermal Performance of a PCM Layer-Filled Triple Glazed Window under Iraqi Climate Conditions

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.

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.

A new validated TRNSYS module for phase change material-filled multi-glazed windows

Incorporating phase change materials (PCM) into multi-glazed windows (MW) has been recognized as an effective way to regulate the indoor thermal environment and reduce the energy consumption of buildings. However, the design and calculation of PCM-filled multi-glazed windows (MW + PCM) remain challenging due to the lack of general transient simulation methods and integrated tools. To address this issue, the present study developed a dynamic coupled thermal and optical model for MW + PCM based on the enthalpy-temperature and interface energy balance methods. Then, the model was implemented in C++ and integrated into the TRNSYS software as a new module (Type 2602). In parallel, a test platform comprising two test chambers was established to evaluate the effect of PCM on the thermal and optical properties of the window and to validate the newly proposed module. It was found that compared to the traditional triple-glazed window (TW), the PCM-filled triple-glazed window (TW + PCM) effectively reduces the irradiance through the window by 34.17 % and the maximum temperature of the inner surface by approximately 5.56 °C. While the increase in external surface radiation flux density from 600 to 1200 W/m2 has a diminishing effect on the heat flux variation rate during the heat dissipation process for TW + PCM, it effectively shortens the latent heat absorption time by 0.50 h and increases the temperature difference between the inner and outer surfaces by 3.02 °C. The new module demonstrates satisfactory accuracy through experimental validation and simulation comparisons, with the maximum heat flux coefficient of variance of the root mean square error (CV(RMSE)) less than 6.35 % and 11.25 % under TW and TW + PCM configurations.

An experimental and numerical investigation of the thermal performance of phase change materials in different triple-glazed window configurations

Phase Change Materials (PCM) may be excellent thermal insulation due to their poor conductivity and high heat capacity. Researchers are adding PCM to windows. This integration modifies internal surface temperatures and delays peak temperatures to improve indoor thermal comfort. This work investigates experimentally and numerically the impact of the different filling materials in four Triple Glazed Windows (TGW) configurations in an Iraqi environment: the first window filled two cavities with air (standard); the second window has one cavity filled with a PCM and the other with air; the third window has blinders with various tilt angles in one cavity and PCM in the other cavity; and in the fourth window, both cavities are filled with PCM. Numerically utilizing Computational Fluid Dynamics to evaluate the thermal performance of TGW. In August, when the solar radiation was at its maximum (623 W/m2), the results showed that the peak interior surface temperature dropped by 4.51, 13.28 and 11.53 % in the TGW configurations (PCM-air), (blinder-PCM), and (PCM-PCM), compared to the standard TGW. The fourth window increased the time lag by 2 h, effectively shifting the load and in the third window, the best tilt angle blinder is 45°

The influence of the climate, the materials of the walls, and the gas effects of double and triple-glazed windows in terms of energy evaluation and economic expenses

The computation of heating and cooling loads for office buildings is influenced by the significant population and diverse occupations of the users throughout various time durations. The first step in this investigation involves using specialized software to simulate a model office structure. To improve the thermal insulation of the building's outside covering and the arrangement of the windows, modifications are performed by considering the appropriate assumptions. Furthermore, this study examined samples of double- and triple-glazed windows using argon, xenon, krypton, air, and vacuum as insulating materials. In addition, the thermal efficiency of this construction was evaluated using common wall materials such as Autoclaved Aerated Concrete (AAC), Educational Credential Assessment (ECA), and Cellular Lightweight Concrete (CLC) blocks. This research conducted a comparison and analysis of four different climates, including Canada, Saudi Arabia, Greece, Sweden, and Iran, with the climate of the study location. The aim of this study is to enhance thermal loads and energy efficiency in a simulated construction. The research demonstrates that arranging windows correctly, implementing efficient wall insulation, and ensuring appropriate climatic conditions may result in a reduction in cooling and heating loads by around 4–8 %. Finally, the economic study demonstrates that the time it takes to recoup the investment for different configurations ranges from 2.4 to 9.3 years. In summary, this research provides significant insights on how to decrease energy consumption in buildings and highlights different approaches that architects and engineers could use to build energy-efficient and sustainable structures.

Effects and Improvements in Carpentry for Thermal Comfort in Educational Spaces in Andean Mild Equatorial Climate

Environmental comfort is fundamental for teaching and learning processes. This work focuses on identifying shortcomings and proposing improvements for educational buildings in the Andean equatorial climate. A quantitative experimental methodology was employed, which included collecting thermal comfort data to calibrate the use of the DesignBuilder v7 environmental simulation software. Issues with thermal weakness in the carpentry were identified, both due to the choice of materials and construction sealing. These are common weaknesses that arise in the context of the Andean Ecuadorian climate, but which affect moments of thermal discomfort during study hours. With the calibrated simulator, thermal improvements achievable by working on the carpentry to reduce infiltrations by half and improving glazing with double-glazed and triple-glazed windows, achieving even uniformity in thermal transmittance compared to other envelope materials, were analyzed. By reducing infiltrations alone, the average temperature increased by between 1.07 °C and 1.61 °C, surpassing the minimum comfort threshold and remaining within locally accepted temperatures throughout the day. With very-high-standard glazing, additional improvements are made, increasing the average temperature by an additional 0.30 °C to 0.69 °C, resulting in a less efficient alternative.

Same product, different score: how methodological differences affect EPD results

Abstract Purpose Demand for Environmental Product Declarations (EPDs) is already high and increasing in the construction and building sectors. The overall purpose of EPDs is comparability of product environmental performance, and they are thus developed in accordance with product category rules (PCRs): requirements and guidelines for how to make EPDs for one or more product groups. Since several organisations publish PCRs, there is a risk of creating conflicting rules leading to inconsistencies and jeopardising the objective of comparability. Methods This study analyses the causes for inconsistency and the consequences in terms of difference in the results across the life cycle assessment (LCA) models underlying the EPDs. Taking four EPD programmes and their actors as cases, first a document analysis was conducted to identify qualitative and quantitative differences in their guidelines. Further focusing on selected quantitative differences, a series of LCA models were designed for the same triple-glazed window product by adhering to the PCRs of each operator, to highlight the differences in results that occur when performing the same assessment via different but all formally selectable operators and compliant EPDs. Results and discussion Results show that the EPD of a specific product can return very different impact scores if one or the other guideline is followed. Results can vary more than 10% from the base scenarios, what we consider a significant variation. This is observed across all impact categories. Focusing specifically on the climate change impact, the results show that differences are due to the choice of energy mix, reference service life and other parameters. It is thus the combination of several modelling differences that leads to a overall divergence in results, rather than one single methodological choice. Conclusions Numerous different but at the same time compliant EPDs can be obtained for the same product, highlighting a serious harmonisation issue within the EPD system. EPDs are thus not necessarily accurate, and it remains doubtful whether EPD comparability can be achieved. This weakness of the EPD system can in the worst case be exploited by producers to obtain lower results and undermines the system. Recommendations Besides recommending using LCA for learning and process improvement rather than just for external communication and compliance, to increase harmonisation in the EPD system, we recommend limiting the number of product-specific PCRs (e.g. complementary PCRs), align default values, learn from verification, use just one background database, increase transparency and move towards one centralized operator.

The Investigation of Indoor Air Temperature Effects for Different Types of Window Dimensions Using CFD Simulation

Windows plays an important role in heat transfer and natural ventilation in buildings. In the field of building design, the challenge is to provide a thermally comfortable indoor environment that requires the least energy consumption to maintain. One of the energy reduction alternatives that can be incorporated into modern building design is the installation of efficient windows. The windows should allow thermally acceptable indoor air quality and have a pleasant design while being energy efficient. Good thermal conditions in school buildings, especially learning spaces, promote the educational process. Unfulfilling comfort levels can reduce the lecturers’ and students' physical and intellectual performance. One of the variables that affect the thermal comfort condition is indoor air temperature. The purpose of this study is to investigate the effect of window size on indoor air temperature by using Computational Fluid Dynamics (CFD) simulation. The selected classroom at Universiti Teknologi MARA (UiTM) Permatang Pauh, Pulau Pinang will be used as a case study. The field measurement result can be used to validate the simulation result. The simulation result will be compared to standard regulations set by the American Society of Heating, Refrigeration, and Air Conditioning Engineers (ASHRAE) Standard 55-2017. Three different sizes of windows have been chosen in this study which are double, triple, and quadruple-glazed windows. The validation result shows the percentage difference in indoor air temperature between the experimental and simulation is 1.04 %. The result found double and triple-glazed windows show the value of temperature under the range set by ASHRAE Standard 55-2017. The selection of triple-glazed windows is more suitable because the brightness of the classroom meets the criteria for the absence of direct solar radiation. In conclusion, the size of the window shows the performance in terms of heat transfer and indoor air temperature of the classroom.

An optimisation study of PCM triple glazing for temperate climatic conditions – Dynamic analysis of thermal performance

PCM-windows can play an important role in the protection of buildings against overheating but also as systems for effective storage of solar energy. The presented study indicated the optimal solution for the triple-glazed window where one cavity is fullfilled with phase change material (PCM) in temperate climatic conditions characteristic for Poland. Regarding different thicknesses, positions, and temperatures of phase change material, the a recommended solution was determined using the simulation technique. The computational model was developed, numerically verified, and experimentally validated. The entire meteorological year analyses were done for the climatic conditions of Central Europe, considering windows exposed to facing the South. The optimal solution was determined using two methods - the Weighted Sum method and the Fuzzy Sets method. Both point out a variant with a PCM layer located in the inner cavity and the average melting temperature of PCM equal to 25 °C. However, different criteria and sets of linguistic variables in fuzzy sets determined different optimal PCM thicknesses ranging from 5 to 20 mm.

On-site testing of dynamic facade system with the solar energy storage

Decarbonistation goals for building stock calls for innovative solutions on both supply and demand side. Thermal envelopes with in-build energy storage could gather on-site solar energy and reduce cooling or heating loads of the buildings. Results of on-site testing of dynamic facade system with the solar energy storage are presented in the paper. Proposed solar façade consists of phase change material to rise the heat capacity of the building envelope, aerogel for insulation, Fresnel lens for solar energy concentration accompanied by moving reflective blades for heat transfer enhancement. Comparative study was conducted in PASLINK type test booths– the performance of proposed solar façade was compared to the reference element – the highest performance triple glazed window suitable for low energy buildings. The detailed measuring setup provide information on the thermal performance of phase-change material enhanced building envelope under different outdoor conditions (summer, autumn, winter) in Northern European climate. The gained results indicate that proposed solar façade module provides lower energy demand during the cooling season compared to the window, in mid-season it performs similarly, however in heating season proposed solar façade in its current composition is outperformed by high performance triple glased window.

A review of the FIVA project: Novel windows employing vacuum glazing products

Vacuum glazing products have been in development for the past decades. Such glazing products regularly feature two parallel glass panes that have a small, evacuated gap in their interstitial space. To maintain the vacuum and the form of the glass product, regularly vacuum tight edge seals and a grid of distance pillars are integrated. During the years of development, the major focus was set on the production and durability aspects of the glass products, but relatively few efforts had been conducted towards the integration of such glass products into window constructions. Employing typically used double- and triple glazing windows’ frames does not represent a feasible option. This is due to the specification given by vacuum glazing products, such as their small thickness and the requirement for sufficient glass edge coverage due to the major thermal bridge adjacent to the edge seal.The authors, together with major players from the window producing industry, started a R&D effort that targeted disruptive new concepts for vacuum glass windows. Four different designs were developed that not only integrated vacuum glass products, but also featured unusual opening patterns, the latest generation of electrically driven fitting products, and specific seals. The thermal and acoustical performance of the prototypes was improved during the development via employment of numeric thermal simulation and lab testing. The present contribution illustrates the four prototypes and their performance, which – for instance – pertaining to the UW-value is down to 0.6–0.7 W · m−2 · K−1 at a glass thickness of less than 1 cm.

Understanding BIPV performance with respect to WWR for energy efficient buildings

Globally, the building sector absorbs 40% of energy, which is expected to reach double or triple by 2050. Building-integrated Photovoltaic (BIPV), known to the use of PV to replace long-established building envelopes such as windows, roofs, and walls which will create energy while simultaneously protecting the inside the structure from the harsh outside environment. The study utilizes Application of BIPV, as a fenestration component in various commercial structures around the United States of America. The paper addresses the dual functionality of PV on fenestrations which not only is an on-site energy generator but also decreases thermal transmittance. To comprehend the significance of BIPV across the United States, five different temperature zones were taken into account: Atlanta, Chicago, Los Angeles, Miami, and Phoenix round out the top five. The component chosen for BIPV is the dye-sensitized solar cell. Using the WINDOW Tool, two alternative BIPV models were computationally created, where the first type of window had two panes with Dye-Sensitized Solar Cells (DSSC) filled between The second model was a three-pane window as opposed to a window with two panes with DSSC and Inert gas filled between the first and second, second and third, and so forth. Three different commercial buildings were considered for the study, from the reference building. Another parameter of variability was introduced such as the Window to Wall Ratio (WWR) [1]. East, West, and South faces of the structure, the most commonly utilized WWR, such as 40%, 60%, and 80%, were taken into consideration. The potential for energy savings was assessed for Every one of these combinations of building type, climate/cities, WWR, and BIPV windows. The study finds an answer, in Triple glazed windows as the most efficient solution in the case of the small building.

A Holistic Framework for Determining the Trade-off between Embodied and Operational Carbon Emissions of High-rise Residential Buildings

Buildings’ carbon emissions consist of embodied carbon (EC) associated with the production and transportation of materials and operational carbon (OC) generated from consumed energy during daily use. However, previous studies concentrated on either EC or OC but ignored an integrated analysis of their relationships. Therefore, this paper aims to explore appropriate building envelope design solutions by examining the trade-off between EC and OC of high-rise residential buildings. To achieve this aim, the life cycle assessment method was used to evaluate the EC and OC of the residential buildings using SimaPro and DesignBuilder software. A building information modelling (BIM) model was developed to extract the geometric data and material consumption. A typical 30-story public residential building in Hong Kong was examined. The EC and OC of the case building were calculated as 561 kg CO2e/m2 and 50.18 kg CO2e/m2/yr, respectively. Different low carbon design scenarios were identified from the literature review and the semi-structured interviews with designers and contractors. Results indicate that low carbon concrete is an effective approach for not only reducing the EC by 5%-15%, but saving a mild percentage of OC, and is therefore encouraged. However, changing the thickness of external walls leads to a very limited life cycle carbon reduction (0.99%). Lower U-value of envelopes is recommended as 2.84% and 2.89% life cycle carbon is reduced when adopting insulations for external walls and triple-glazing windows. The findings are valuable for examining the relationships between EC and OC and can support low carbon building decision-making.

Analysis of building materials used for the construction of family houses in the boundaries from Cradle to Gate with Options

The purpose of the research work is to analyse environmental impacts of building materials applied to the construction of family houses in the boundaries Cradle to Gate with Options. Within Life cycle analysis (LCA), environmental impacts such as global warming potential (GWP), ozone depletion (OP), acidification potential (AP), eutrophication potential (EP), photochemical ozone creation potential (POCP), non-hazardous waste disposal (NHWD) and biogenic carbon storage (BGS) are determined by using One Click LCA tool. This approach is selected to bring information about current state of construction trend used in Slovakia, to set a starting point for further critical reviews of different strategies as well as to inform about the impact significance of current selection of building materials. Results show that the biggest contribution to GWP are triple glazed exterior wooden doors and windows with aluminium elements, thermal insulation and reinforced concrete.

Benefitting from Solar Energy Due to Different Emissivity Levels of Multiple Glass Windows for Buildings

In the study, firstly, heat transfer coefficients of windows were calculated according to the highest and lowest emissivity values. Secondly, monthly average solar radiation values were determined. The heat transfer coefficient calculated for double, triple and quadruple glass windows. Thirdly, the solar radiation in the south, north and east/west directions of the five climatic zones were multiplied by the shading factor, surface area and the solar energy factor of discrete buildings. Thus, the solar energy gain value for the heating period and solar energy losses for cooling period was determined. Finally, passive solar energy gains are calculated during the heating and cooling period for all climate zones. It has been calculated that in the fifth climatic zone in south direction, heat loss from windows with 0.05 emissivity can be provided with passive solar energy by 167.9% in double-glazed windows, 258.7% in triple-glazed windows and 349.1% in quadruple-glazed windows.

A Comparison of Energy and Daylighting Performances of Different Window Glazing Types Used in the Traditional Harput House

A review of the history of glass that dates back to the mid-2000 BC pursuant to the archaeological data suggests that the effects of the thermophysical properties of window glass on building energy performance could have been understood only over time. Today, the optimum combinations of thermophysical parameters help significantly reduce the energy demand of the buildings. Furthermore, the energy sustainability is also achieved by increasing building energy efficiency during the early design phase, using building simulation tools. The present study was aimed to comprehensively review the improvements in glazing technologies from past to present. Furthermore, the energy and daylighting performances of the retrofitted traditional Harput house in Turkey were analyzed using a building simulation tool. The results indicated that the use of retrofit measure, i.e., the triple-glazed window with low-e coating filled with Argon gas combined with daylighting control system improved the annual primary energy performance of the building in question located in a cold climatic region of Turkey by %8.20. In addition, it was found that the illuminance of indoors increased by means of higher visible transmittance ensured by the retrofit measure.

Simplified Thermal Performance Evaluation of a PCM-Filled Triple-Glazed Window under Arctic Climate Conditions

This paper evaluates the thermal performance of a triple-glazed glass window filled with a phase-change material (PCM) compared to the performance of a traditional triple-glazed window with air gaps. The chosen PCM was paraffin wax. A mathematical model to simulate heat transfer within the system was presented. A commercially available software, COMSOL Multiphysics, was used to numerically solve the governing equations. The analysis was carried out for the representative days of different seasons using three types of paraffin wax (5, 10, and 15) that have different melting-temperature ranges. Particularly, the study considers the unique climatic conditions of the Arctic region. Results showed that by integrating a PCM into the cavity of triple-glazing, thermal performance during summer season of the window was enhanced, while for spring and autumn thermal performance was affected by the type of paraffin selected. The thermal performance of glass windows during winter did not change with PCM integration.

Assessment and optimisation of life cycle environment, economy and energy for building retrofitting

Building retrofitting plays a vital role in realising net-zero carbon ambition. Conventional retrofitting solutions are generally based upon decreasing operating energy usage or corresponding costs. However, many of these would increase the embodied carbon and energy. The innovation of this paper is to develop a building retrofitting assessment and optimisation approach to select the optimal combination of retrofitting options to minimise its carbon emissions, economic costs and energy usage over its life cycle. A real-life three-floor real-world office building is implemented to exhibit the behaviour of the newly developed retrofitting assessment and optimisation approach. This paper mainly focuses on passive options, including improving envelope thermal properties (e.g. wall insulations, roof insulations and triple-glazed windows) and installing renewable energy devices (e.g. photovoltaic panel, solar heater and wind turbine). The effects of varying embodied carbon, investment cost, embodied energy, annual salvage ratio, and material recycle ratio on the life cycle behaviour of the retrofitted building is investigated. For cost optimisation, the selection priority is sheep wool for roof insulation, insulation board for wall insulation, solar heater and wind turbine. The selection priority for energy or carbon optimisation would be insulation board for wall insulation, sheep wool for roof insulation, solar heater, triple-glazed window, and wind turbine. The largest achievable reduction in life cycle carbon, cost and energy are 3.9 × 106 kg, £3.6 × 105 and 7.8 × 107 MJ, respectively. The research outcome will benefit the government for policymaking on approach-based net-zero retrofitting guidance and building engineers for designing sustainable retrofitting measures.