Pub Date : 2025-03-17DOI: 10.1016/j.enbuild.2025.115628
Taylana Piccinini Scolaro, Enedir Ghisi
Roofs significantly impact urban microclimates and indoor environments. However, selecting a suitable roof typology is complex due to environmental, social, and economic issues. This study aims to propose a method that comprises four parameters to support the selection of the most sustainable roof typology: life cycle energy assessment, urban heat island, life cycle cost analysis and thermal comfort. A top-floor flat in a multifamily residential building model with conventional (fibre cement), cool and green roofs, with and without thermal insulation, was used as a case study. The Brazilian climatic contexts of Florianópolis, Curitiba, and Brasília were considered. Computer simulations on EnergyPlus and data from the literature, technical specifications, a Brazilian database for quantifying materials and services and market prices were used to assess the roof typologies’ performance in each parameter. A questionnaire was applied to a panel of building experts to define the relative importance of each parameter. A multi-criteria decision-making (MCDM) method combining Analytic Hierarchy Process (AHP) and Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS) was used to weigh the parameters and select the most energy-sustainable roof alternative for each climatic context. The cool roof was the most sustainable in Florianópolis and Brasília, whereas the green roof was in Curitiba. Conventional roofs performed worst in all cities due to lower environmental and social efficiency. The method proposed herein offers valuable guidance for selecting energy-sustainable roofs and urban planning strategies, with adaptability to other roof typologies and countries, enabling tailored roof solutions for local conditions.
{"title":"Life cycle integrated multi-criteria decision model for roof assessment","authors":"Taylana Piccinini Scolaro, Enedir Ghisi","doi":"10.1016/j.enbuild.2025.115628","DOIUrl":"10.1016/j.enbuild.2025.115628","url":null,"abstract":"<div><div>Roofs significantly impact urban microclimates and indoor environments. However, selecting a suitable roof typology is complex due to environmental, social, and economic issues. This study aims to propose a method that comprises four parameters to support the selection of the most sustainable roof typology: life cycle energy assessment, urban heat island, life cycle cost analysis and thermal comfort. A top-floor flat in a multifamily residential building model with conventional (fibre cement), cool and green roofs, with and without thermal insulation, was used as a case study. The Brazilian climatic contexts of Florianópolis, Curitiba, and Brasília were considered. Computer simulations on EnergyPlus and data from the literature, technical specifications, a Brazilian database for quantifying materials and services and market prices were used to assess the roof typologies’ performance in each parameter. A questionnaire was applied to a panel of building experts to define the relative importance of each parameter. A multi-criteria decision-making (MCDM) method combining Analytic Hierarchy Process (AHP) and Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS) was used to weigh the parameters and select the most energy-sustainable roof alternative for each climatic context. The cool roof was the most sustainable in Florianópolis and Brasília, whereas the green roof was in Curitiba. Conventional roofs performed worst in all cities due to lower environmental and social efficiency. The method proposed herein offers valuable guidance for selecting energy-sustainable roofs and urban planning strategies, with adaptability to other roof typologies and countries, enabling tailored roof solutions for local conditions.</div></div>","PeriodicalId":11641,"journal":{"name":"Energy and Buildings","volume":"336 ","pages":"Article 115628"},"PeriodicalIF":6.6,"publicationDate":"2025-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143644894","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The European Union’s imperative to achieve climate neutrality by 2050 demands specific intervention for existing buildings. The Pro-GET-onE European project, funded by Horizon 2020, contributes to this agenda by focusing on energy efficiency and seismic resilience through innovative technologies tailored for building envelopes. This strategy was tested on a specific pilot case of a student residence in Athens, Greece, on which an exoskeleton in steel was implemented for both increasing volumes and enhancing the energy and seismic performance of the building. This paper presents comprehensive Life Cycle Assessment (LCA) and Life Cycle Cost (LCC) analyses and a circularity assessment of sustainable strategies for deep renovation and sustainable reconstruction using the One Click LCA tool. Focusing on Global Warming Potential (GWP), this study first assesses the environmental impacts associated with five different construction technologies for demolition with reconstruction scenarios; then, it compares the smartest one with the pre-renovation state, deep renovation scenario, and Pro-GET-onE strategy. This study considers factors such as energy consumption, circularity of materials, and economic feasibility by evaluating different costs, including construction, operation, maintenance, and end-of-life. The environmental impact analysis over 50 years reveals that the renovation scenario minimizes CO2 emissions due to the reduction of energy consumption; however, it does not provide seismic safety. The economic impact analysis indicates that even with a high initial investment, demolition with reconstruction using Glulam and CLT represents the most cost-effective solution over the building’s lifecycle, providing both high energy and structural performance. In contrast, the deep renovation and Pro-GET-onE scenarios entail higher costs but present numerous advantages, such as low service disruption, avoiding residents’ relocation, and smaller time duration. The conclusions of this study highlight the transformative potential of Pro-GET-onE measures in achieving environmental sustainability and decarbonization. This research underscores the importance of LCC and LCA methodologies in evaluating project feasibility and cost-effectiveness, providing valuable insights for policymakers, building owners, and stakeholders. Understanding the long-term economic and environmental implications of construction and renovation projects is crucial for informed decision-making and guiding the building sector toward its energy efficiency and environmental goals.
{"title":"Circular deep renovation versus demolition with reconstruction: Environmental and financial evaluation to support decision making in the construction sector","authors":"Lorna Dragonetti , Dimitra Papadaki , Cecilia Mazzoli , Alice Monacelli , Margarita-Niki Assimakopoulos , Annarita Ferrante","doi":"10.1016/j.enbuild.2025.115610","DOIUrl":"10.1016/j.enbuild.2025.115610","url":null,"abstract":"<div><div>The European Union’s imperative to achieve climate neutrality by 2050 demands specific intervention for existing buildings. The Pro-GET-onE European project, funded by Horizon 2020, contributes to this agenda by focusing on energy efficiency and seismic resilience through innovative technologies tailored for building envelopes. This strategy was tested on a specific pilot case of a student residence in Athens, Greece, on which an exoskeleton in steel was implemented for both increasing volumes and enhancing the energy and seismic performance of the building. This paper presents comprehensive Life Cycle Assessment (LCA) and Life Cycle Cost (LCC) analyses and a circularity assessment of sustainable strategies for deep renovation and sustainable reconstruction using the <em>One Click LCA</em> tool. Focusing on Global Warming Potential (GWP), this study first assesses the environmental impacts associated with five different construction technologies for demolition with reconstruction scenarios; then, it compares the smartest one with the pre-renovation state, deep renovation scenario, and Pro-GET-onE strategy. This study considers factors such as energy consumption, circularity of materials, and economic feasibility by evaluating different costs, including construction, operation, maintenance, and end-of-life. The environmental impact analysis over 50 years reveals that the renovation scenario minimizes CO<sub>2</sub> emissions due to the reduction of energy consumption; however, it does not provide seismic safety. The economic impact analysis indicates that even with a high initial investment, demolition with reconstruction using Glulam and CLT represents the most cost-effective solution over the building’s lifecycle, providing both high energy and structural performance. In contrast, the deep renovation and Pro-GET-onE scenarios entail higher costs but present numerous advantages, such as low service disruption, avoiding residents’ relocation, and smaller time duration. The conclusions of this study highlight the transformative potential of Pro-GET-onE measures in achieving environmental sustainability and decarbonization. This research underscores the importance of LCC and LCA methodologies in evaluating project feasibility and cost-effectiveness, providing valuable insights for policymakers, building owners, and stakeholders. Understanding the long-term economic and environmental implications of construction and renovation projects is crucial for informed decision-making and guiding the building sector toward its energy efficiency and environmental goals.</div></div>","PeriodicalId":11641,"journal":{"name":"Energy and Buildings","volume":"336 ","pages":"Article 115610"},"PeriodicalIF":6.6,"publicationDate":"2025-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143645114","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-03-15DOI: 10.1016/j.enbuild.2025.115609
Xinyi Hu , Juha Jokisalo , Risto Kosonen , Matti Lehtonen
Rural houses in China’s severe cold climate face pressing challenges due to harsh winter conditions, outdated construction, and inefficient energy systems, leading to high energy costs and poor indoor air quality. This study proposed a holistic renovation approach, incorporating key renovation measures across building envelope upgrade, ventilation improvement, and distributed energy system application. Simulation-based multi-objective optimization was utilized to explore optimal solutions, which balanced two key objectives: minimizing both net present value of life cycle cost and CO2 emissions of energy use. Future scenarios assessed the sensitivity of optimal solutions to factor changes regarding thermal comfort, economic, and energy environmental impacts. Results indicate that a biomass pellet boiler achieves the greatest emission reduction, followed by PV-combined air-to-water heat pump, natural gas heater, PV-combined electric boiler and electric boiler, lowering CO2 emissions from 109.4 kg CO2/m2 to 10.7–53.4 kg CO2/m2. The holistic renovation reduces emissions more efficiently than only focusing on envelope upgrades. Cases with heat pump and biomass pellet boiler even show lower life cycle cost than standard envelope renovation. These findings offer valuable insights for decision-makers, supporting the adoption of clean energy solutions in rural areas facing extreme climatic conditions.
{"title":"Cost-effective and low-carbon solutions for holistic rural building renovation in severe cold climate","authors":"Xinyi Hu , Juha Jokisalo , Risto Kosonen , Matti Lehtonen","doi":"10.1016/j.enbuild.2025.115609","DOIUrl":"10.1016/j.enbuild.2025.115609","url":null,"abstract":"<div><div>Rural houses in China’s severe cold climate face pressing challenges due to harsh winter conditions, outdated construction, and inefficient energy systems, leading to high energy costs and poor indoor air quality. This study proposed a holistic renovation approach, incorporating key renovation measures across building envelope upgrade, ventilation improvement, and distributed energy system application. Simulation-based multi-objective optimization was utilized to explore optimal solutions, which balanced two key objectives: minimizing both net present value of life cycle cost and CO<sub>2</sub> emissions of energy use. Future scenarios assessed the sensitivity of optimal solutions to factor changes regarding thermal comfort, economic, and energy environmental impacts. Results indicate that a biomass pellet boiler achieves the greatest emission reduction, followed by PV-combined air-to-water heat pump, natural gas heater, PV-combined electric boiler and electric boiler, lowering CO<sub>2</sub> emissions from 109.4 kg CO<sub>2</sub>/m<sup>2</sup> to 10.7–53.4 kg CO<sub>2</sub>/m<sup>2</sup>. The holistic renovation reduces emissions more efficiently than only focusing on envelope upgrades. Cases with heat pump and biomass pellet boiler even show lower life cycle cost than standard envelope renovation. These findings offer valuable insights for decision-makers, supporting the adoption of clean energy solutions in rural areas facing extreme climatic conditions.</div></div>","PeriodicalId":11641,"journal":{"name":"Energy and Buildings","volume":"336 ","pages":"Article 115609"},"PeriodicalIF":6.6,"publicationDate":"2025-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143644895","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-03-14DOI: 10.1016/j.enbuild.2025.115600
Zahra Jandaghian , Hossein Arasteh , Davoud Heidari , Mehdi Ghobadi , Michael Lacasse , Bradford Gover
The building sector is a major contributor to global greenhouse gas emissions, accounting for approximately 40% of total energy-related CO2 emissions. The growing urban heat island (UHI) effect and the rising energy demand for cooling have intensified the need for innovative building materials that enhance thermal efficiency while minimizing environmental impact. Despite advancements in cool wall cladding materials, knowledge gaps remain regarding their long-term performance, scalability, and the trade-offs between embodied carbon and operational energy savings. This study addresses these gaps by conducting a comprehensive review of recent developments in cool wall technologies, with a focus on advanced solutions such as radiative cooling coatings, retroreflective surfaces, and high-emissivity paints. A systematic review of approximately thousand peer-reviewed journal articles and conference papers, published within the last decade and sourced from Google Scholar and Scopus, was conducted to evaluate these advancements. Studies were selected based on their relevance to urban heat mitigation, energy efficiency, and life cycle assessment of building envelopes. The review examines both numerical modeling techniques (e.g., Finite Element Method (FEM), Finite Volume Method (FVM), and Computational Fluid Dynamics (CFD) simulations) and experimental validations to assess the effectiveness of cool wall materials. The findings indicate that while these technologies effectively reduce surface and ambient temperatures, their net carbon reduction potential is influenced by material selection, insulation properties, and regional climatic conditions. Notably, under optimal conditions, cool cladding materials can achieve net carbon reductions through operational energy savings, despite variations in embodied carbon impacts. However, challenges such as long-term durability, scalability, and potential heating penalties in colder climates highlight the need for further research into adaptive emissivity technologies and cost-effective manufacturing methods. Addressing these challenges will enable cool wall cladding materials to play a transformative role in developing energy-efficient and climate-resilient buildings.
{"title":"Cool wall claddings for a sustainable future: A comprehensive review on mitigating urban heat island effects and reducing carbon emissions in the built environment","authors":"Zahra Jandaghian , Hossein Arasteh , Davoud Heidari , Mehdi Ghobadi , Michael Lacasse , Bradford Gover","doi":"10.1016/j.enbuild.2025.115600","DOIUrl":"10.1016/j.enbuild.2025.115600","url":null,"abstract":"<div><div>The building sector is a major contributor to global greenhouse gas emissions, accounting for approximately 40% of total energy-related CO<sub>2</sub> emissions. The growing urban heat island (UHI) effect and the rising energy demand for cooling have intensified the need for innovative building materials that enhance thermal efficiency while minimizing environmental impact. Despite advancements in cool wall cladding materials, knowledge gaps remain regarding their long-term performance, scalability, and the trade-offs between embodied carbon and operational energy savings. This study addresses these gaps by conducting a comprehensive review of recent developments in cool wall technologies, with a focus on advanced solutions such as radiative cooling coatings, retroreflective surfaces, and high-emissivity paints. A systematic review of approximately thousand peer-reviewed journal articles and conference papers, published within the last decade and sourced from Google Scholar and Scopus, was conducted to evaluate these advancements. Studies were selected based on their relevance to urban heat mitigation, energy efficiency, and life cycle assessment of building envelopes. The review examines both numerical modeling techniques (e.g., Finite Element Method (FEM), Finite Volume Method (FVM), and Computational Fluid Dynamics (CFD) simulations) and experimental validations to assess the effectiveness of cool wall materials. The findings indicate that while these technologies effectively reduce surface and ambient temperatures, their net carbon reduction potential is influenced by material selection, insulation properties, and regional climatic conditions. Notably, under optimal conditions, cool cladding materials can achieve net carbon reductions through operational energy savings, despite variations in embodied carbon impacts. However, challenges such as long-term durability, scalability, and potential heating penalties in colder climates highlight the need for further research into adaptive emissivity technologies and cost-effective manufacturing methods. Addressing these challenges will enable cool wall cladding materials to play a transformative role in developing energy-efficient and climate-resilient buildings.</div></div>","PeriodicalId":11641,"journal":{"name":"Energy and Buildings","volume":"336 ","pages":"Article 115600"},"PeriodicalIF":6.6,"publicationDate":"2025-03-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143629372","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-03-14DOI: 10.1016/j.enbuild.2025.115608
Xue Zhang, Yunxi Cheng, Huanxin Chen, Henda Cheng, Yi Gao
Variable Refrigerant Flow (VRF) air conditioning systems are prone to refrigerant charge faults due to improper human operation or external factors during long-term operation, leading to reduced system performance and energy waste. To address this issue, this paper studies, for the first time, the diagnostic performance of the Kolmogorov–Arnold Network (KAN) and its convolutional neural network variant (Conv-KAN) for diagnosing refrigerant charge faults in VRF systems under cooling conditions, introducing new methods to the field of fault diagnosis in air conditioning systems. From the VRF refrigerant charge fault experiments, 18 significant feature variables were collected and subjected to data preprocessing. Using the processed datasets, the structures and parameters of various neural network models were optimized. Subsequently, the models’ performances were compared from multiple dimensions such as convergence speed, model performance change curves, and confusion matrices. Finally, comparisons were made with traditional models, and significance tests were conducted based on the comparison results. The results show that both KAN and Conv-KAN outperform traditional neural network models in terms of convergence speed and diagnostic accuracy, achieving diagnostic accuracies of 99.24 % and 99.02 %, respectively, which are 3.86 % and 0.04 % higher than traditional neural network models. Further comparisons with KNN, SVM, and decision tree algorithms reveal that KAN and Conv-KAN still exhibit better performance. This study not only demonstrates the excellent performance of KAN in diagnosing VRF refrigerant charge faults but also compares it with traditional neural network models, contributing to research in this field.
{"title":"Refrigerant charge fault diagnosis in VRF systems using Kolmogorov-Arnold networks and their convolutional variants: A comparative analysis with traditional models","authors":"Xue Zhang, Yunxi Cheng, Huanxin Chen, Henda Cheng, Yi Gao","doi":"10.1016/j.enbuild.2025.115608","DOIUrl":"10.1016/j.enbuild.2025.115608","url":null,"abstract":"<div><div>Variable Refrigerant Flow (VRF) air conditioning systems are prone to refrigerant charge faults due to improper human operation or external factors during long-term operation, leading to reduced system performance and energy waste. To address this issue, this paper studies, for the first time, the diagnostic performance of the Kolmogorov–Arnold Network (KAN) and its convolutional neural network variant (Conv-KAN) for diagnosing refrigerant charge faults in VRF systems under cooling conditions, introducing new methods to the field of fault diagnosis in air conditioning systems. From the VRF refrigerant charge fault experiments, 18 significant feature variables were collected and subjected to data preprocessing.<!--> <!-->Using the processed datasets, the structures and parameters of various neural network models were optimized. Subsequently, the models’ performances were compared from multiple dimensions such as convergence speed, model performance change curves, and confusion matrices.<!--> <!-->Finally, comparisons were made with traditional models, and significance tests were conducted based on the comparison results. The results show that both KAN and Conv-KAN outperform traditional neural network models in terms of convergence speed and diagnostic accuracy, achieving diagnostic accuracies of 99.24 % and 99.02 %, respectively, which are 3.86 % and 0.04 % higher than traditional neural network models. Further comparisons with KNN, SVM, and decision tree algorithms reveal that KAN and Conv-KAN still exhibit better performance. This study not only demonstrates the excellent performance of KAN in diagnosing VRF refrigerant charge faults but also compares it with traditional neural network models, contributing to research in this field.</div></div>","PeriodicalId":11641,"journal":{"name":"Energy and Buildings","volume":"336 ","pages":"Article 115608"},"PeriodicalIF":6.6,"publicationDate":"2025-03-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143645113","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-03-14DOI: 10.1016/j.enbuild.2025.115607
Iván Negrin , Moacir Kripka , Víctor Yepes
The construction industry significantly contributes to global energy consumption and emissions, necessitating sustainable alternatives to conventional practices. In this context, this study introduces a novel composite structural typology that combines reinforced concrete (RC) columns with transversely hybrid variable section (THVS) steel girders as beam-type elements. The proposed building frame leverages the high horizontal stiffness of RC columns and the reduced weight of steel girders to lower material consumption. The THVS variant has proven to be one of the most sustainable steel I-girder configurations. Two arrangements are analyzed: one with fixed beam-column connections and another with pinned joints. Structural design optimization problems are formulated, targeting three objectives: economic cost, CO2(e) emissions, and embodied energy. These indicators are evaluated using a “cradle-to-site” approach. Results demonstrate that the fixed connection typology is optimal for buildings with shorter spans (4 m), achieving reductions in economic cost (6 %), emissions (16 %), and embodied energy (11 %) compared to traditional RC structures. The pinned variant is more suitable for longer span buildings (8 m), resulting in economic gains of around 5 % and a 6 % reduction in emissions despite higher energy requirements. Optimal THVS configurations indeed employ higher-grade steels in flanges than in the web, with tapered geometries varying by span length and connection type. The study also highlights that the THVS girders’ lighter weight significantly lowers axial loads on columns and foundations, further reducing construction costs and environmental impacts of the structural assembly. These findings underscore the potential of composite designs to enhance sustainability in building construction.
{"title":"Design optimization of a composite typology based on RC columns and THVS girders to reduce economic cost, emissions, and embodied energy of frame building construction","authors":"Iván Negrin , Moacir Kripka , Víctor Yepes","doi":"10.1016/j.enbuild.2025.115607","DOIUrl":"10.1016/j.enbuild.2025.115607","url":null,"abstract":"<div><div>The construction industry significantly contributes to global energy consumption and emissions, necessitating sustainable alternatives to conventional practices. In this context, this study introduces a novel composite structural typology that combines reinforced concrete (RC) columns with transversely hybrid variable section (THVS) steel girders as beam-type elements. The proposed building frame leverages the high horizontal stiffness of RC columns and the reduced weight of steel girders to lower material consumption. The THVS variant has proven to be one of the most sustainable steel I-girder configurations. Two arrangements are analyzed: one with fixed beam-column connections and another with pinned joints. Structural design optimization problems are formulated, targeting three objectives: economic cost, CO<sub>2</sub>(e) emissions, and embodied energy. These indicators are evaluated using a “cradle-to-site” approach. Results demonstrate that the fixed connection typology is optimal for buildings with shorter spans (4 m), achieving reductions in economic cost (6 %), emissions (16 %), and embodied energy (11 %) compared to traditional RC structures. The pinned variant is more suitable for longer span buildings (8 m), resulting in economic gains of around 5 % and a 6 % reduction in emissions despite higher energy requirements. Optimal THVS configurations indeed employ higher-grade steels in flanges than in the web, with tapered geometries varying by span length and connection type. The study also highlights that the THVS girders’ lighter weight significantly lowers axial loads on columns and foundations, further reducing construction costs and environmental impacts of the structural assembly. These findings underscore the potential of composite designs to enhance sustainability in building construction.</div></div>","PeriodicalId":11641,"journal":{"name":"Energy and Buildings","volume":"336 ","pages":"Article 115607"},"PeriodicalIF":6.6,"publicationDate":"2025-03-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143637296","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-03-14DOI: 10.1016/j.enbuild.2025.115597
Federico Rossi , Alessia Di Giuseppe , Abdul Rehman Soomro , Andrea Nicolini , Mirko Filipponi , Beatrice Castellani
Cool materials are essential for reducing energy demand in buildings and for mitigating the Urban Heat Island (UHI) phenomenon. Their effectiveness relies on two primary physical properties: the ability to reflect solar energy and the capacity to emit infrared radiation, both of which are especially beneficial on horizontal surfaces like roofs and pavements. However, vertical surfaces, such as façades, also play a significant role in urban thermal balance. Conventional materials often underperform on these surfaces due to non-directional properties. This study measures the emissivity of Retro-Reflective (RR) materials, investigating their behaviour in the thermal infrared range. Results show that emissivity depends just on the superficial temperature and there are no angular variations. Therefore, RR materials have a directional behaviour only in the reflected radiation and not in the emitted one. Since emissivity is one of the parameters used in the calculation of the Cooling Power Potential (CPP), a critical knowledge gap regarding the CPP of RR coatings at varying orientations was found in literature. To address this limitation, an original measurement campaign was conducted, where several kinds of RR materials were realized by varying the size and density of embedded glass beads. RR materials significantly enhance CPP compared to conventional diffusive surfaces. At a typical façade temperature of 55 °C, RR materials increased CPP by an average of 20 %, demonstrating their superior cooling capability. Further research should focus on the long-term durability and environmental impact of RR materials to ensure their effectiveness over time.
{"title":"Radiative cooling improvement by retro-reflective materials","authors":"Federico Rossi , Alessia Di Giuseppe , Abdul Rehman Soomro , Andrea Nicolini , Mirko Filipponi , Beatrice Castellani","doi":"10.1016/j.enbuild.2025.115597","DOIUrl":"10.1016/j.enbuild.2025.115597","url":null,"abstract":"<div><div>Cool materials are essential for reducing energy demand in buildings and for mitigating the Urban Heat Island (UHI) phenomenon. Their effectiveness relies on two primary physical properties: the ability to reflect solar energy and the capacity to emit infrared radiation, both of which are especially beneficial on horizontal surfaces like roofs and pavements. However, vertical surfaces, such as façades, also play a significant role in urban thermal balance. Conventional materials often underperform on these surfaces due to non-directional properties. This study measures the emissivity of Retro-Reflective (RR) materials, investigating their behaviour in the thermal infrared range. Results show that emissivity depends just on the superficial temperature and there are no angular variations. Therefore, RR materials have a directional behaviour only in the reflected radiation and not in the emitted one. Since emissivity is one of the parameters used in the calculation of the Cooling Power Potential (CPP), a critical knowledge gap regarding the CPP of RR coatings at varying orientations was found in literature. To address this limitation, an original measurement campaign was conducted, where several kinds of RR materials were realized by varying the size and density of embedded glass beads. RR materials significantly enhance CPP compared to conventional diffusive surfaces. At a typical façade temperature of 55 °C, RR materials increased CPP by an average of 20 %, demonstrating their superior cooling capability. Further research should focus on the long-term durability and environmental impact of RR materials to ensure their effectiveness over time.</div></div>","PeriodicalId":11641,"journal":{"name":"Energy and Buildings","volume":"336 ","pages":"Article 115597"},"PeriodicalIF":6.6,"publicationDate":"2025-03-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143637297","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-03-14DOI: 10.1016/j.enbuild.2025.115612
Abdulmunem R. Abdulmunem , Izhari Izmi Mazali , Pakharuddin Mohd Samin , Kamaruzzaman Sopian , Habibah Ghazali
Applying bio-based phase change materials (BPCM) using environmentally acceptable resources as an alternative to petroleum-based phase change materials (PCM) in buildings presents an opportunity to reduce greenhouse gas emissions to almost zero, besides decreasing energy consumption in achieving thermal comfort in a building. Thus, this research aims to investigate numerically and experimentally the melting behavior of stearin of sheep tail-fats (SSTF) as the BPCM in a rectangular cavity acting as the sustainable building envelope, as well as the effects of carbon nanotube (CNT) additives on the SSTF melting behaviors. The results suggest that the convection heat transfer mechanism plays an important role in the heat transfer within the SSTF envelope due to its poor thermal conductivity. This leads to the non-uniform melting progress inside the container. The inclusion of 0.03% CNT in the SSTF leads to a slight increase in the thermal conductivity of the SSTF composite because of the high number of the CNTs’ tangled tube bundles inside the SSTF. When compared to the SSTF without the CNT, it quickens the melting process and the melted SSTF’s velocity (the convection strength) by about 11% and 8.7%, respectively. Not only that, it also enhances the heat transfer and the thermal storage rate by about 13.7% and 7.5% respectively. Therefore, this research concludes that the SSTF with CNT as the additive offers a potential to be the effective passive TES envelopes for the building walls that leads to a potential application in the low-carbon thermal comfort control of buildings.
{"title":"Bio-phase change materials based on stearin of sheep tail-fats loaded with nanoparticles: Melting performance analysis in rectangular cavity as a sustainable building envelopes","authors":"Abdulmunem R. Abdulmunem , Izhari Izmi Mazali , Pakharuddin Mohd Samin , Kamaruzzaman Sopian , Habibah Ghazali","doi":"10.1016/j.enbuild.2025.115612","DOIUrl":"10.1016/j.enbuild.2025.115612","url":null,"abstract":"<div><div>Applying bio-based phase change materials (BPCM) using environmentally acceptable resources as an alternative to petroleum-based phase change materials (PCM) in buildings presents an opportunity to reduce greenhouse gas emissions to almost zero, besides decreasing energy consumption in achieving thermal comfort in a building. Thus, this research aims to investigate numerically and experimentally the melting behavior of stearin of sheep tail-fats (SSTF) as the BPCM in a rectangular cavity acting as the sustainable building envelope, as well as the effects of carbon nanotube (CNT) additives on the SSTF melting behaviors. The results suggest that the convection heat transfer mechanism plays an important role in the heat transfer within the SSTF envelope due to its poor thermal conductivity. This leads to the non-uniform melting progress inside the container. The inclusion of 0.03% CNT in the SSTF leads to a slight increase in the thermal conductivity of the SSTF composite because of the high number of the CNTs’ tangled tube bundles inside the SSTF. When compared to the SSTF without the CNT, it quickens the melting process and the melted SSTF’s velocity (the convection strength) by about 11% and 8.7%, respectively. Not only that, it also enhances the heat transfer and the thermal storage rate by about 13.7% and 7.5% respectively. Therefore, this research concludes that the SSTF with CNT as the additive offers a potential to be the effective passive TES envelopes for the building walls that leads to a potential application in the low-carbon thermal comfort control of buildings.</div></div>","PeriodicalId":11641,"journal":{"name":"Energy and Buildings","volume":"336 ","pages":"Article 115612"},"PeriodicalIF":6.6,"publicationDate":"2025-03-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143637744","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-03-14DOI: 10.1016/j.enbuild.2025.115602
Salma Kouzzi , Sara El Hassani , Souad Morsli , Mohammed El Ganaoui , Mohammed lhassane Lahlaouti
Energy-efficient wall systems are vital for sustainable construction, especially in humid Mediterranean climates. This study assesses the thermal and hygrothermal performance of four double hollow brick wall assemblies incorporating various insulation materials: air gaps, hemp wool, and phase change materials (PCMs) combined with hemp wool. Simulations were conducted using WUFI Pro software to analyze heat and moisture transfer under the Mediterranean climate of Tetouan, Morocco. The results reveal that the configuration with PCM placed before hemp wool delivers optimal performance. This setup achieves a thermal transmittance (U-value) of 0.38 W/m2·K, representing a reduction of 47 % compared to regulatory maximum standards. This configuration also demonstrates effective moisture control, keeping the hemp wool moisture content below the critical threshold of 18 % throughout the entire simulation period, thus preventing condensation and mold growth. In contrast, the air gap configuration failed to meet thermal standards and showed increased risks of mold growth. The PCM placed after hemp wool, while achieving a favorable U-value (0.38 W/m2·K), led to significant condensation at the critical interfaces with hemp wool. The highest mold growth was recorded at the right interface near the indoor environment (1632 mm), compromising long-term hygrothermal stability. These findings emphasize the importance of optimizing PCM placement and highlight the synergistic effects of combining PCM with hemp wool to enhance energy efficiency and indoor comfort. This study underscores the potential of such sustainable insulation systems in reducing energy demand while ensuring hygrothermal stability in humid Mediterranean buildings.
{"title":"Hygrothermal analysis of external walls with hemp wool and phase change materials insulation in Mediterranean climate: A case study of Tetouan, Morocco","authors":"Salma Kouzzi , Sara El Hassani , Souad Morsli , Mohammed El Ganaoui , Mohammed lhassane Lahlaouti","doi":"10.1016/j.enbuild.2025.115602","DOIUrl":"10.1016/j.enbuild.2025.115602","url":null,"abstract":"<div><div>Energy-efficient wall systems are vital for sustainable construction, especially in humid Mediterranean climates. This study assesses the thermal and hygrothermal performance of four double hollow brick wall assemblies incorporating various insulation materials: air gaps, hemp wool, and phase change materials (PCMs) combined with hemp wool. Simulations were conducted using WUFI Pro software to analyze heat and moisture transfer under the Mediterranean climate of Tetouan, Morocco. The results reveal that the configuration with PCM placed before hemp wool delivers optimal performance. This setup achieves a thermal transmittance (U-value) of 0.38 W/m<sup>2</sup>·K, representing a reduction of 47 % compared to regulatory maximum standards. This configuration also demonstrates effective moisture control, keeping the hemp wool moisture content below the critical threshold of 18 % throughout the entire simulation period, thus preventing condensation and mold growth. In contrast, the air gap configuration failed to meet thermal standards and showed increased risks of mold growth. The PCM placed after hemp wool, while achieving a favorable U-value (0.38 W/m<sup>2</sup>·K), led to significant condensation at the critical interfaces with hemp wool. The highest mold growth was recorded at the right interface near the indoor environment (1632 mm), compromising long-term hygrothermal stability. These findings emphasize the importance of optimizing PCM placement and highlight the synergistic effects of combining PCM with hemp wool to enhance energy efficiency and indoor comfort. This study underscores the potential of such sustainable insulation systems in reducing energy demand while ensuring hygrothermal stability in humid Mediterranean buildings.</div></div>","PeriodicalId":11641,"journal":{"name":"Energy and Buildings","volume":"336 ","pages":"Article 115602"},"PeriodicalIF":6.6,"publicationDate":"2025-03-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143637743","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-03-14DOI: 10.1016/j.enbuild.2025.115613
Mehran Bozorgi, Syeda Humaira Tasnim, Shohel Mahmud
The rising demand for energy-efficient cooling systems in Multi-Unit Residential Buildings (MURBs) presents a challenge, as traditional centralized systems often lead to excessive energy consumption, especially during peak demand periods. Addressing this issue requires innovative solutions that can reduce both the size of the central system and overall energy use, while still maintaining thermal comfort for occupants. This study proposes a novel hybrid cooling system that combines a central cooling system with localized thermoelectric coolers. A key innovation in this research is the use of a Machine Learning (ML) model to predict real-time cooling loads based on factors such as temperature, humidity, solar radiation, and occupancy. The system was evaluated through simulations conducted for a 40-unit MURB in Toronto, Canada, over the summer months. System components included solar evacuated tube collectors, absorption chillers, phase change material storage, and thermoelectric coolers. Cooling load analysis revealed that the building operates near peak capacity for less than 10 % of the time, underscoring the potential for hybrid system optimization. A Machine Learning model was developed to control the operation of the thermoelectric coolers, achieving a high R-squared value (R2 = 0.9937) and a SMAPE of 15.87 %, ensuring accurate cooling load predictions. Results showed that both the central and hybrid systems provided acceptable thermal comfort, with PMV and PPD values within acceptable ranges. However, the hybrid system demonstrated higher energy efficiency, achieving a COP of 1.36 compared to 1.28 for the central system. These findings establish the hybrid cooling system, integrated with ML-based control, as a viable and sustainable solution for reducing energy consumption and enhancing cooling performance in residential buildings.
{"title":"Machine learning-driven hybrid cooling system for enhanced energy efficiency in multi-unit residential buildings","authors":"Mehran Bozorgi, Syeda Humaira Tasnim, Shohel Mahmud","doi":"10.1016/j.enbuild.2025.115613","DOIUrl":"10.1016/j.enbuild.2025.115613","url":null,"abstract":"<div><div>The rising demand for energy-efficient cooling systems in Multi-Unit Residential Buildings (MURBs) presents a challenge, as traditional centralized systems often lead to excessive energy consumption, especially during peak demand periods. Addressing this issue requires innovative solutions that can reduce both the size of the central system and overall energy use, while still maintaining thermal comfort for occupants. This study proposes a novel hybrid cooling system that combines a central cooling system with localized thermoelectric coolers. A key innovation in this research is the use of a Machine Learning (ML) model to predict real-time cooling loads based on factors such as temperature, humidity, solar radiation, and occupancy. The system was evaluated through simulations conducted for a 40-unit MURB in Toronto, Canada, over the summer months. System components included solar evacuated tube collectors, absorption chillers, phase change material storage, and thermoelectric coolers. Cooling load analysis revealed that the building operates near peak capacity for less than 10 % of the time, underscoring the potential for hybrid system optimization. A Machine Learning model was developed to control the operation of the thermoelectric coolers, achieving a high R-squared value (R<sup>2</sup> = 0.9937) and a SMAPE of 15.87 %, ensuring accurate cooling load predictions. Results showed that both the central and hybrid systems provided acceptable thermal comfort, with PMV and PPD values within acceptable ranges. However, the hybrid system demonstrated higher energy efficiency, achieving a COP of 1.36 compared to 1.28 for the central system. These findings establish the hybrid cooling system, integrated with ML-based control, as a viable and sustainable solution for reducing energy consumption and enhancing cooling performance in residential buildings.</div></div>","PeriodicalId":11641,"journal":{"name":"Energy and Buildings","volume":"336 ","pages":"Article 115613"},"PeriodicalIF":6.6,"publicationDate":"2025-03-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143644896","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}