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In recent years, there has been significant progress in the development and application of phase change materials (PCMs) for thermal energy storage. The new lauric acid (LA)/polyvinyl butyral (PVB)/graphene nanoplates (GNP) composite phase change materials (CPCM) are prepared using the solution blending method, in which LA acts as PCM, PVB serves as support material, and GNP is used as thermally conductive enhancer. The prepared CPCM with 80 wt% LA can retain stable shape without leakage. The Fourier‐transform infrared and X‐ray diffractometer results indicate that there is no chemical reaction among the various components of the CPCM. The differential scanning calorimeter results show the CPCM3 (with 80 wt% LA and 5 wt% GNP) has melting latent heat of 134.41 KJ Kg−1 with melting temperature of 41.73 °C. The thermal conductivity tests present that thermal conductivity of CPCM3 is 0.689 W (m K)−1, which is 3.83 times that of the PCM2. The thermogravimetric analyzer results verify that the CPCM possess good thermal stability within the operating temperature range of 35–45 °C without any degradation. The thermal cycling tests indicate that CPCM have good thermal reliability. Therefore, it has promising applications in building energy conservation, solar thermal systems, thermal management, and textiles. [ABSTRACT FROM AUTHOR]

Improving the energy efficiency of buildings is one of the main challenges facing Europe in the context of climate neutrality policy. In this article, the authors decided to investigate the impact of thermal insulation of building envelopes and the type of ventilation on the energy efficiency of multi-family buildings located in different Polish cities. In accordance with EU directives, economic analyses of the costs incurred during the lifecycle and calculations of C O 2   emissions were carried out for the analyzed facilities. It was determined what measures need to be taken under Polish climatic conditions in order to meet the requirements for improving the energy efficiency of multi-family buildings. The multi-criteria analyses presented in this article provide a voice in the discussion of the issues related to the achievement of the energy performance of buildings with almost zero primary energy demand (nZEB). Based on the conclusions of the research conducted, it was possible to develop general recommendations for investors and designers of multi-family residential buildings characterized by energy efficiency and reduced environmental impact. [ABSTRACT FROM AUTHOR]

The building envelope is the interface between the external atmospheric conditions and the indoor environment. It contributes to approximately 60%-70% of the heating and cooling load. The building envelope constitutes walls, fenestrations, and roofs from which thermal transfer from the roof is significantly very high compared to walls in low-rise buildings. This research paper aims to provide recommendations for energy-efficient roof design considering roof form, material, and external coating suitable for various climate conditions of India. The paper's methodology consists of a literature review of related research papers, learnings from the roofing system of energy-efficient building case studies, and all possible energy-efficient roofing systems that would be simulated for energy efficiency and thermal comfort in five climate types of India. The expected outcome of this paper would be in the form of recommendations for roofing systems in different climate type and their potential for energy saving from the highest to the lowest. This research would be done in three stages viz, Step-1: Literature Review and case study of best practices: A review of the related literature and best practices examples would be done to formulate the maximum possible cases for the simulation. Step-2: The roofing systems, including building form, material (Thermal and insulation), and finishes (reflectance), would be simulated one by one for various climate types of India (composite, hot & dry, warm and humid, moderate and cold) to optimize energy efficiency and payback period. Step-3: Special roof types like Green roofs, cool roofs, Photovoltaic roofs, roof ponds, and the like are simulated and compared for their effectiveness in selected climate types. Based on the literature review, simulation results, and analysis, the recommendations are framed for energy-efficient roofing systems in the selected climate type with respect to heat transfer through the roof and thermal comfort. [ABSTRACT FROM AUTHOR]

Electrochromic (EC) smart window can dynamically alter optical property under the electric field, showing great potential in building energy conservation. Nickel oxide (NiO) acts as one of the most promising EC candidates while suffering insufficient reaction sites and low electrical conductivity. Herein, we introduced Mn2+ ions into NiO for the heteroatom doping towards improved EC performance. As expected, NiO–Mn–3 film exhibited optimal transmittance modulation (81.8 %) and fast coloring/bleaching time (3.5/5.1 s), which were considerably related to the improved specific surface area and increased electronic conductivity. Electrochemical characterization confirmed that the enhanced ions diffusion coefficient and lowered resistance delivered a positive impact on boosting the EC property. Mott–Schottky study also confirmed that the heteroatom doping effectively increased the carrier concentration. Our results not only provided important insight into a promising electrode material for EC energy–saving application, but also offered an economic and effective synthetic strategy for other doped metal oxide films. [Display omitted] • Mn2+ was introduced into NiO for the heteroatom doping by a CBD method. • The doped sample with reserved porous structure exhibited enhanced conductivity. • The heteroatom doping delivered a positive impact on boosting the EC property. • Mott–Schottky study confirmed that doping increased the carrier concentration. [ABSTRACT FROM AUTHOR]

The built environment is a significant contributor to global energy consumption and greenhouse gas emissions. Advancements in the adoption of environmentally friendly building technology have become crucial in promoting sustainable development. These advancements play a crucial role in conserving energy. The aim is to achieve an optimal design by balancing various interrelated factors. The emergence of innovative techniques to address energy conservation have been witnessed in the built environment. This review examines existing research articles that explore different metaheuristic optimization techniques (MOTs) for energy conservation in buildings. The focus is on evaluating the simplicity and stochastic nature of these optimization techniques. The findings of the review present theoretical and mathematical models for each algorithm and assess their effectiveness in problem solving. A systematic analysis of selected algorithms using MOT is conducted, considering factors that influence wellbeing, occupant health, and indoor environmental quality. The study examines the variations among swarm intelligence MOTs based on complexity, advantages, and disadvantages. The algorithms' performances are based on the concept of uncertainty in consistently providing optimal solutions. The paper highlights the application of each technique in achieving energy conservation in buildings. [ABSTRACT FROM AUTHOR]

As the impact of climate change intensifies, meeting the energy demand of buildings in China's cold regions is becoming increasingly challenging, particularly in terms of cooling energy consumption. The effectiveness of integrating phase change material (PCM) into building envelopes for energy saving in China's cold regions is unclear. The aim of this study is to assess the effectiveness of PCM integration in building enclosures for energy efficiency in these regions. The research monitored and recorded indoor temperature data from typical residential cases from May to September. This measured data was then used to validate the accuracy of EnergyPlus22-1 software simulation models. Subsequently, the calibrated model was utilized to conduct a comparative analysis on the effects of PCM on indoor temperatures and cooling energy consumption across these regions. The results of these comparative analyses indicated that PCM can alleviate indoor overheating to varying degrees in severe cold regions of China. Focusing on north-facing bedrooms, applying PCMs reduced the duration of overheating in non-air-conditioned buildings in severe cold regions of China by 136 h (Yichun), 340 h (Harbin), 356 h (Shenyang), and 153 h (Dalian). In terms of cooling energy consumption, the energy saved by applying PCMs ranged from 1.48 to 13.83 kWh/m2. These results emphasize that the performance of PCM varies with climate change, with the most significant energy-saving effects observed in severe cold regions. In north-facing bedrooms in Harbin, the energy-saving rate was as high as 60.30%. Based on these results, the study offers guidance and recommendations for feasible passive energy-saving strategies for buildings in severe cold and cold regions of China in the face of climate change. Additionally, it provides practical guidance for applying PCMs in different climatic zones in China. [ABSTRACT FROM AUTHOR]

In order to understand the energy-saving system of building cooling and heating integration, the author proposes a research on an energy-saving system of building cooling and heating integration based on building information modelling (BIM) technology. The author first analyzed the energy-saving performance of the system by establishing models for each module based on meteorological data simulated on the DeST software platform. Secondly, in order to analyze the energy consumption of the integrated system, it is necessary to establish a residential building model, and select the building model in the cold winter and hot summer areas of a city for analysis. The results show that due to the system's heat storage function, there is no need to consume electricity in spring and autumn. Compared to the electric heating hot water mode, the integrated system can save 1198.85 kWh of electricity in non-cooling and heating seasons, with a 100% energy-saving rate. Compared to not using an integrated system, it can achieve an energy-saving rate of 81.9% throughout the entire refrigeration and heating season, with significant energy-saving effects. The integrated heating, cooling and hot water system of BIM technology adopts the technology of cool storage and heat storage coupled with solar energy and heat pump technology. The system has simple structure, obvious energy-saving effect, good environmental protection, and can adapt to various climates throughout the year. The introduction of underfloor heating also increases the comfort of buildings and residences. [ABSTRACT FROM AUTHOR]

Aiming at energy saving and consumption reduction, this project applies the technology of combined heating and cooling heat pump to ecological building design. The combined hot and cold system is an integrated control system, which utilizes the solar system and heat pump technology (air source heat pump, water source heat pump) to complement each other based on changes in the outdoor environment, thus providing users with hot water heating and cold water cooling in winter. After installing a new heating and cooling system, coupled with well-equipped automatic control equipment, the heating coal consumption has been significantly reduced, and the emissions of CO2, SO2 dust, and other pollutants have also been correspondingly reduced. Compared with the cold and hot split supply system using electric refrigeration and thermal heating, the winter and summer sharing of the cold and hot combined supply device not only improves energy utilization efficiency, but also saves investment in heat source construction, thereby reducing costs and environmental pollution. [ABSTRACT FROM AUTHOR]

It is a well-known issue that the 2050 target of carbon emissions neutrality will be reached only with the co-operation of all the interested sectors, and the construction sector could be one of the main contributors to this change. With the built environment globally responsible for about 40% of annual global energy-related CO2 emissions, the construction sector offers an important opportunity to drive transformative change and presents the most challenging mitigation potential among all industrial sectors, which also brings opportunities for adopting sustainability practices and increasing resilience. This paper presents a systematic literature review of those two pivotal concepts to reach the decarbonization goal: sustainability and resilience. Starting from an extensive literature review (2536 scientific documents) based on the PRISMA statement, the definitions and assessment methodologies of those concepts for the construction sector have been studied. The methodological approach followed for their analysis has been conducted on a first selection of 42 documents, further reduced to 12 by using clear inclusion criteria to identify the integrated assessment procedures. The main goal of this study is to clarify the correlation between sustainability and resilience concepts for constructions and their integrated assessment, in line with the latest regulations and market needs. The results show that, currently, sustainability and resilience are mainly evaluated in a distinct way to obtain building energy performance certificates, as well as to quantify the building market value and its complementary contribution to the 'energy efficiency first' principle and energy-saving targets towards the emergent issue of climate change. Few works focus on the integrated assessment of both concepts considering the construction industries' point of view about materials and/or systems for buildings. The novelty of this study is the critical review of the current sustainability and resilience integrated assessment methods used for the construction value chain, declined for four main target groups. Researchers, policymakers, industries, and professionals could gain dedicated insights and practical suggestions to put in practice the elements of circular economy, ecological innovation, and cleaner production, which are essential in order to drive the decarbonization of the built environment. [ABSTRACT FROM AUTHOR]

This study aims to theoretically explore the technological systems of tropical island zero-carbon building (TIZCB) to scientifically understand the characteristics of these buildings in terms of energy utilization, energy conservation, energy production, and intelligent system mechanisms. The purpose is to address the inefficiencies and resource wastage caused by the traditional segmented approach to building energy consumption management. Thus, it seeks to achieve a comprehensive understanding and application of the zero-carbon building (ZCB) technology system. This article focuses on the demands for energy-efficient comfort and innovative industrialization in construction. Through an analysis of the characteristics of TIZCB and an explanation of their concepts, it establishes a theoretical framework for examining the system mechanisms of these buildings. Additionally, it delves into the energy utilization, energy conservation, energy production, and intelligent system from macro, meso, and micro perspectives. This approach results in the development of an implementation strategy for studying the mechanisms of energy usage, conservation, and intelligent production systems in TIZCB. The results show that: (1) this study delves into the theoretical underpinnings of TIZCB, emphasizing their evolution from a foundation of low-carbon and near-zero energy consumption. The primary goal is to achieve zero carbon emissions during building operation, with reliance on renewable energy sources. Design considerations prioritize adaptation to high-temperature and high-humidity conditions, integrating regional culture along with the utilization of new materials and technologies. (2) A comprehensive technical framework for TIZCB is proposed, encompassing energy utilization, conservation, production capacity, and intelligent systems. Drawing from systems theory, control theory, and synergy theory, the research employs a macro–meso–micro analytical framework, offering extensive theoretical support for the practical aspects of design and optimization. (3) The research implementation plan establishes parameterized models, unveiling the intricate relationships with building performance. It provides optimized intelligent system design parameters for economically viable zero-carbon operations. This study contributes theoretical and practical support for the sustainable development of TIZCB and aligns with the dual carbon strategy in China and the clean energy free trade zone construction in Hainan. [ABSTRACT FROM AUTHOR]

It is of great significance to analyze the calorific value and carbon dioxide emission level of coal with different degrees of coalification for energy conservation and emission reduction in coal-fired power plants, and elemental carbon and fixed carbon are closely related to the carbon dioxide emission level and calorific value. Due to the complexity of matrix effects and differences in regression tasks, modeling only all coal samples will limit the quantitative performance of laser-induced breakdown spectroscopy (LIBS). In this work, we combine a dual-cycle variable selection mechanism with competitive adaptive reweighted sampling to optimize partial least squares regression (PLSR). According to the difference between coal samples in coal quality characteristics and prediction tasks, the matrix correction of elemental carbon and fixed carbon is realized by qualitative classification and by using generalized spectra (GS), respectively. The coefficient of determination (R2) of the training set and test set of elemental carbon was improved from 0.7178 and 0.7095 to 0.9534 and 0.9515, respectively. The root-mean-square error of cross-validation (RMSECV) and the root-mean-square error of prediction (RMSEP) decreased from 1.1723 wt% and 1.2488 wt% to 0.4504 wt% and 0.4871 wt%, respectively. The R2 of the training set and test set of fixed carbon was also improved from 0.8252 and 0.8236 to 0.9814 and 0.9749. The RMSECV and RMSEP decreased from 1.2274 wt% and 1.3548 wt% to 0.4421 wt% and 0.4711 wt%, respectively. According to Chinese national standards and IPCC guidelines, the maximum error in CO2 emission factors for all coal samples during the accounting period is 1.7581%. Taking into account the level of CO2 emissions and the net calorific value, the selection of coal with different degrees of coalification can guide the combustion of mixed coal in power plants to achieve high efficiency and clean power generation. This work demonstrates the great potential of in situ LIBS for online applications in coal-fired power plants. [ABSTRACT FROM AUTHOR]

Addressing Europe's decarbonisation challenge involves widespread deployment of nearly zero-energy buildings, deep energy renovations and renewable energy integration in the building sector. Enhancing energy efficiency in public buildings necessitates tailored solutions and strategic planning involving Local Public Administration. This work focuses on advancing insights into the application of the PrioritEE Decision Support Tool in Portuguese public buildings, highlighting the energy and financial savings and carbon dioxide emission reduction potential. Using detailed building characterisation data from energy performance certificates, we applied the tool across 22 public buildings of diverse typologies in three distinct regions of Portugal, representing various public entities. Results demonstrate the tool's adaptability, enabling a comprehensive assessment of energy performance and facilitating the exploration of customised energy efficiency and renewable energy solutions. The research emphasises the critical role of user-friendly tools in aiding policymakers and local administration technicians in meeting national renovation targets and contributing to the broader energy transition objectives. [ABSTRACT FROM AUTHOR]

Electrochromic devices have important applications in building energy conservation, next‐generation displaying, and security encryption, while durable and high‐performance electrochromic materials are highly desirable. Herein, a Zn‐based electrochromic smart window by using 3D ordered macroporous amorphous WO3 (a‐WO3) arrays as cathode is reported. Benefiting from a 3D ordered macroporous structure with a high specific surface area that accelerates the ion diffusion and migration, and the oxygen vacancy modulated a‐WO3 providing abundant zinc ion insertion channels, the as‐fabricated zinc‐based a‐WO3 inverse opal (a‐WO3‐IO) device exhibits excellent electrochromic properties, including large light modulation (83% optical contrast at 700 nm), fast response time (5.3 s for coloring and 3.2 s for bleaching), and robust cycling stability. Moreover, a solid‐state a‐WO3‐IO prototype electrochromic smart window is demonstrated for light modulation, electronic display, and power supply. Furthermore, experimental results and theoretical calculations reveal that 3D macroporous amorphous WO3 with rich oxygen vacancies can enhance the zinc ion absorption and diffusion, leading to the enhancement of electrochromic performance. [ABSTRACT FROM AUTHOR]

In the wake of increasing global concern over environmental change and energy consumption, building energy conservation has emerged as a pivotal issue worldwide. The primary energy consumption in buildings stems largely from air conditioning and heating systems. The efficiency of these systems is significantly influenced by the thermal performance of the building's exterior wall insulation layers. In-depth research and optimized design of these insulation layers' thermal performance are thus critical topics in the field of building energy conservation. However, current research methods encounter limitations in addressing these issues, notably neglecting the impact of thermal bridges on the insulation layers' thermal performance and focusing solely on single parameters in insulation optimization design. This study addresses these challenges by conducting a comprehensive analysis and optimization design of the thermal performance of building exterior wall insulation layers. It includes an analysis of heat transfer through thermal bridges and the optimization of insulation parameters, aiming to provide a more holistic and systematic approach to optimizing the thermal performance of building exterior wall insulation layers. Specifically, this study uses thermal simulation software to conduct three-dimensional simulation of thermal bridges, analyzing the temperature distribution and heat flow in the thermal bridge area. According to international or domestic standards, the linear heat transfer coefficient of the thermal bridge is determined through calculation. By using optimization algorithms, the thermal performance parameters of the insulation layer are optimized in design. Through experiments, specific linear heat transfer coefficient and equivalent heat transfer coefficient of thermal bridges are obtained, as well as the extent of the impact of thermal bridges on overall thermal performance. Meanwhile, based on optimization algorithms, a set of materials and structural parameters that enable the building's external wall insulation layer to achieve higher thermal efficiency is obtained. After optimization, a lower heat transfer coefficient of the external wall insulation layer is achieved, improving the insulation performance of the wall. This paper provides a technical method for the analysis of heat transfer in thermal bridges and the optimization of insulation parameters. It helps architects more accurately assess and improve the thermal performance of building exteriors, which is significant for reducing energy loss and lowering operational costs of buildings. The research results can provide scientific basis for the formulation of building energy-saving standards, especially in terms of thermal bridge effects and external wall insulation performance. These standards are crucial in driving the industry towards higher energy-saving goals. [ABSTRACT FROM AUTHOR]

To accurately describe the thermal comfort of indoor occupant used to regulate heating, ventilation and air conditioning (HVAC) system is a key goal to reduce energy consumption in intelligent buildings. In this paper, we propose a noncontact measurement of occupant thermal discomfort behavior as an index of thermal comfort. The method takes the existing monitoring image data in the building as the input to infer the occupant thermal discomfort directly, which saves the cost because there is no need to install new sensors in the building and the occupant does not need to wear additional equipment. The framework combined three channels of body posture, motion and performance information to infer occupant thermal discomfort behavior, it consists of a human detection and crop module, a posture analysis module, an optical flow extraction module and a 3D convolutional neural network module. The three channels describe the actions from different perspectives, and the proposed method makes full use of the complementarity of the three modalities to identify the occupant's thermal discomfort behaviors. Sixteen postures related to thermal discomfort were identified through a questionnaire, and 14,800 video clips containing these postures were collected for experimental evaluation. The results demonstrate the superior performances of our approach to the state-of-the-art techniques. The framework achieves noninvasive, cost-effective thermal comfort evaluation, and has potential value in improving energy efficiency of HVAC systems. [ABSTRACT FROM AUTHOR]

This study presents an in-depth analysis of 69 case studies focusing on the energy retrofit of historic buildings, uncovering challenges, best practices, and lessons learned to balance energy efficiency improvements with heritage preservation. The findings highlight several challenges encountered during renovations, such as complex heritage evaluations, restrictions on alterations, coordination issues with authorities, technical limitations, higher investment costs, and knowledge gaps. On the other hand, identifying factors promoting renovation, including demonstrating energy savings while respecting heritage, early collaboration between planners and authorities, and quantifying investments, could incentivize owners and authorities. The limitations of a still-limited sample size, occasional incomplete data, and potential sample bias call for cautious interpretation of the presented analysis. Despite these, the study provides valuable insights into successful projects, emphasizing the need for scalability, knowledge transfer from innovative policies, and targeted policy-making for successful replication. The study concludes with a call for further development of the HiBERatlas (Historic Building Energy Retrofit atlas), an extensive resource for historic building renovation, expanding its database, collaborating with agencies, and tailoring guidance for stakeholders to foster energy retrofits in heritage buildings. [ABSTRACT FROM AUTHOR]

The traditional way of designing the parameters of university buildings is to base designs on the experience of designers after surveying the local environment, but this approach is time consuming and laborious. The research problem addressed by this paper is the quick optimisation of the parameters of university buildings with the goal of energy saving. First, a model of energy consumption and lighting of university buildings was constructed; then, a particle swarm optimisation (PSO) algorithm modified by a genetic algorithm was used to optimise the building parameters; this was compared with the traditional PSO algorithm in a case study. The results were that the PSO algorithm improved by the genetic algorithm converged the building parameter scheme to stability faster, the scheme fitness value at stability was lower than that of the traditional PSO algorithm and the improved PSO algorithm required less computation time in optimising the building parameter scheme. [ABSTRACT FROM AUTHOR]

According to the latest energy efficiency European directive (EED 2023/1791/EU), the expected energy renovation rate of at least 3% of the buildings' floor area each year towards nearly zero-energy buildings (nZEBs) is extended to include public buildings not only of the central government (as per the first EED 2012/27/EU) but also of regional and local authorities. This poses a great challenge, especially for Municipalities that often manage large building stocks with high energy demands. In response to this challenge, this paper presents the application of the so-called "typology approach" for conducting public buildings' energy renovation plans at the local level. A computational survey is initially introduced to decide the optimal set of building-stock clustering criteria among all possible combinations, involving the minimization of the RMSE index regarding the primary energy consumption of each building. For a representative building from each identified typology, the key performance indicators (KPIs) are computed for alternative energy-upgrading scenarios. Exploiting the IMPULSE Interreg-MED project tools, the KPIs from each representative building are at first extrapolated to all buildings of the examined stock and, finally, a gradual energy renovation plan is automatically produced based on user-defined decision parameters including the required annual renovation rate. The methodology is applied for the case of the Municipality of Hersonissos in Greece. For the specific 44-buildings' stock it was found that the optimal clustering set included four criteria, building use, construction year, heating, and a cooling system, leading to 15 building typologies. Finally, assuming a 7% renovation rate per year, a 12-year gradual renovation (nZEB transformation) plan is obtained foreseeing an 85% CO2 emissions' reduction. [ABSTRACT FROM AUTHOR]

Phase‐change material (PCM) has great thermal energy ability, which has been used as building material for energy conservation. While the most widely used solid–liquid PCM usually appeared leakage during the phase change transition. In order to overcome the leakage of solid–liquid PCM and prepare a viable building energy‐saving materials for indoor temperature regulation, thermal energy storage composites were prepared by utilizing cellulose grafted PEG as phase change material (PCM) and high‐density polyethylene (HDPE) as the substrate. The liquid leakage of PEG was solved after graft to fabricate solid–solid PCM. HDPE is beneficial for solving the leakage and improving the mechanical property by its secondary encapsulation. The synthesized Cellulose‐PEG was characterized by scanning electron microscopy (SEM), X‐ray diffractometer (XRD), and differential scanning calorimetry (DSC). Thermal and mechanical characteristics of the composite were explored. The outcomes revealed that: (1) PEG was successfully grafted to the surface of cellulose and Cellulose‐PEG showed solid–solid phase change behavior. (2) Both the melting‐cooling temperatures and the thermal stability of solid–solid wood plastic composite (SSWPC) had the potential as thermal energy storage material for temperature regulating. (3) The addition of Cellulose‐PEG adversely affected moisture resistance, flexural property, and impact strength due to the weak interface bonding. The physical and mechanical degradation was tolerable for applying situation where mechanical performance is less crucial. Highlights: Cellulose‐PEG showed solid–solid phase change behavior without liquid leakage.High‐density polyethylene (HDPE) was used as the matrix to realize the second encapsulation of PCM.Cellulose‐PEG negatively influenced the physical and mechanical property of HDPE.Solid–solid wood plastic composite presented great thermal storage capacity for indoor temperature regulating. [ABSTRACT FROM AUTHOR]

Smart photovoltaic windows (SPWs) are an emerging green technology presenting energy‐saving by combining solar irradiance regulation and solar energy harvesting. The SPWs integrating extraordinary energy‐saving performance, stable and controllable operational mode, and diverse functionality are essential for devising high efficiency energy‐saving buildings (ESBs). However, the attainment of such features has yet to be realized in current iterations of SPWs. Herein, a conceptual demonstration of a split‐type broadband modulation, self‐driven, and self‐cleaning SPWs is presented by coupling a silicon solar cell with a multifunctional chromogenic unit (MCU) for creating highly efficient ESBs. Within the multilayer structured MCU, thermal‐responsive polymer stabilized liquid crystal (PSLC) and VO2@SiO2 nanoparticles act as chromic component, enabling broadband light modulation. Thanks to the excellent electrothermal effect of indium tin oxide (ITO), the phase transition of PSLC and VO2@SiO2 nanoparticles can be induced by the electrical power output generated by the silicon solar cell. Therefore, the transparency of SPWs can be manipulated according to the occupant's preference during the daytime. Moreover, a superhydrophobic SiO2 coating provides SPWs with self‐cleaning capability which effectively reduces water resource consumption and eliminates the inconvenience of window cleaning, while providing occupants with a clear view even in complex weather conditions. [ABSTRACT FROM AUTHOR]

In order to reduce the energy consumption of buildings, an air source heat pump assisted rooftop photovoltaic-thermal integration system is designed. The installation area of photovoltaic modules and collectors will not only affect the power side, but also affect the thermal side. Therefore, the basic architecture of the photovoltaic photothermal integration system is first established, and then the improved whale algorithm is used to optimize the photovoltaic photothermal integration system with the daily operating cost as the optimization goal. At the same time, the influence of the installation area of the photovoltaic photothermal module on the comprehensive performance of the system is analyzed, and the environmental and economic benefits of the photovoltaic photothermal system are analyzed. The results of the example show that the roof of the building has significant benefits in environmental protection and investment recovery period when the photovoltaic photothermal system with the optimal area ratio is installed on the roof of the building. The solar photovoltaic power generation system can reduce carbon dioxide emissions by 147.11 t within 25 years, and the solar collector system can save 170.5 thousand yuan in 1 year. It has achieved the purpose of saving energy, reducing carbon dioxide emissions and protecting the environment. [ABSTRACT FROM AUTHOR]

Energy conservation in buildings is paramount, especially considering that glass accounts for 50% of energy consumption. The solar heat gain coefficient (SHGC) of glass is a critical energy-saving index for transparent structures. However, the fixed SHGC of ordinary glass makes it difficult to provide both summer shading and winter heating. In this study, we synthesized a hydrogel with a thermosensitive scattering (TS) property using triblock polyether and acrylamide. This hydrogel can realize the transition of clearness and atomization based on the temperature. When sealed within a glass cavity, it exhibits a high SHGC of 0.682 in its transparent state and a low SHGC of less than 0.31 when atomized. The lower critical solution temperature (LCST) of the TS glass can be adjusted from 0 to 70 °C to suit different regions. The photothermal properties of the material remained stable after 200 hot and cold cycles and 200 h of ultraviolet irradiation. This glass can prevent solar radiation from entering the room in summer, thereby reducing air conditioning usage and power consumption. In winter, it allows solar heat radiation to enter the room, minimizing the need for artificial heating. Its adaptable temperature design makes it an excellent solution for designers to create energy-efficient building exteriors. [ABSTRACT FROM AUTHOR]

This article discusses the main concept of sustainable tourism to comprehend the terminology on definition, aspects, and main concept. Furthermore, the discussion continues on how architecture plays an important part in achieving the sustainability of tourist attraction areas, and the practical ways that have been done from an architectural perspective. The discussion in the architecture subject is divided into 2 parts: the heritage building and new building, and how the architectural decision in those areas plays part in supporting sustainable tourism. In heritage building tourism, it is important to maintain the building is in good condition physically and also functional. Adaptive re-use is mainly being used to revitalize heritage buildings. In new buildings, there are several ways that can be done to support sustainability in tourism and its usually by designing an environmentally low negative impact building's design. If these strategies applied in buildings design, it is possible to develop a tourism area that emphasizes the concept of sustainability. [ABSTRACT FROM AUTHOR]

As people put forward higher demand for the effect and quality of building interior decoration, the attention to building energy-saving materials has become higher and higher. In recent years, there have been many researches on green building energy-saving technology, green building evaluation and other aspects, but there are relatively few researches on applying the concept of full life cycle cost to the performance analysis of new materials for building energy conservation and environmental protection. Considering the economic performance of buildings will help to save resources in the construction industry and reduce energy consumption. The so-called full life cycle optimization of energy-saving design of green buildings is to take the concept of full life cycle optimization as the most reference, fully coordinate all elements in the portfolio project, and ensure that the full life cycle cost of the building can be greatly reduced. To realize the energy-saving optimization of green buildings, it is necessary to ensure that it runs through the whole life cycle of the building, fully combine the life cycle cost with the building function, and systematically do the optimization work. The performance analysis model of building decoration energy-saving and environmental protection new materials based on the whole life cycle proposed in this paper can be used to analyse the various properties of various new materials. The experimental results show that the maximum error of the test results is 9.6%, the minimum error is 1.3%, and the average error is only 6.43%. This shows that the model built in this paper is reliable, and the calculated results are in good agreement with the experimental results, which can be used to analyse the performance of new building decoration energy-saving and environmental protection materials. The ideas and methods of solving the model established in this paper have important guiding significance, and can be used as a powerful reference tool for studying other solving methods. [ABSTRACT FROM AUTHOR]

Strengthening the thermal response of Phase-Change Materials (PCMs) is an essential and active field of research with promising potential for advanced applications such as solar energy storage, building energy conservation, and thermal management in electronic devices. This article evaluates the efficacy of a new arc-shaped fin array in shell-and-tube heat storage systems to enhance the PCM response during the discharge mode. Different fin geometric parameters including the fin curvature angle, the fin spacing, and the nonuniform angle between fins in the top and bottom sections of the PCM domain were considered to identify the best-performing layout. The analysis shows that increasing the curvature of arc-shaped fins between 60° and 180° and increasing the fin spacing between 5 and 15 mm can significantly reduce solidifying time and improve heat recovery rates. Moreover, the arc-shaped fins are more efficient than conventional longitudinal (+-shaped) fins, which are commonly employed in thermal energy storage applications. Arc-shaped fins can also save discharge time by more than half and improve the rate of heat recovery by almost four times than that of+-shaped fins. The present findings suggest that arc-shaped fins represent a promising design for enhancing the heat-recovery aspects in PCM-based energy storage systems. [ABSTRACT FROM AUTHOR]

The current applications in the energy sector are based largely on fossil fuels which release greenhouse gas emissions to the atmosphere. To face the issue of global warming, the energy sector has to transfer to and develop sustainable energy solutions that do not release carbon emissions. This is one of the primary motivators for the SDEWES conference as well as for this review, and previous ones, examining the most recent works based on sustainable and green energy production in such fields. The 17th Conference on the Sustainable Development of Energy, Water, and Environment Systems (SDEWES) was held on 6–10 November 2022 in Paphos, Cyprus. The SDEWES conference aims at solving complex and ongoing concerns that approach a long-term perspective and supporting innovative solutions and continuous monitoring and evaluation. This review paper aims at collecting the main presented papers focused on the following hot topics: low-carbon technologies based on renewable and clean-energy systems, including mainly biomass, solar, and wind energy applications; energy storage systems; hydrogen-based systems; energy-saving strategies in buildings; and the adoption of smart management strategies using renewable energy systems. These topics are investigated in order to propose solutions to address the issues of climate change, water scarcity, and energy saving. From the analyzed works, we note that some key issues for sustainable development remain to be further addressed: such as novel and advanced energy storage systems, green hydrogen production, novel low-temperature district heating and cooling networks, novel solar technologies for the simultaneous production of power and high temperature heat, solar desalination for hydrogen production systems, and agrivoltaic systems for the production of power and food. [ABSTRACT FROM AUTHOR]

The continuous growth of residential buildings has led to increasing attention on energy consumption and emission reduction. Taking an old residential building in Zhengzhou as an example, this article used Dest-h to simulate and calculate its energy-savings. A nine-factor, three-level orthogonal table was designed to analyze factors such as external wall heat transfer coefficient and building orientation, to understand the impact of different factors on energy savings. The results showed that among the 27 orthogonal experiments, the cooling consumption of experiment 23 was the lowest (21,236 kWh); the heating consumption of experiment 20 was the lowest (11,376 kWh); experiment 25 had the lowest total energy consumption (37,416 kWh). The comprehensive energy-saving rate was 36.12%, 43.29%, and 49.02%, respectively, in experiments 23, 20, and 25 as compared to the existing building. The annual energy-saving benefits were 6.57 yuan/m², 7.87 yuan/m², and 8.91 yuan/m², respectively. Among the nine factors studied, the heat transfer coefficients of the external wall and window had the greatest impact on the energy savings of this building. In the case of minimum total energy consumption, the heat transfer coefficient of the external wall was 0.6 W/(m²·K), and that of the external window was 0.8 W/(m²·K). The results prove the reliability of Dest-h in building energy conservation research, and it can be applied to practical research on energy consumption and emission reduction. [ABSTRACT FROM AUTHOR]

Summary: This manuscript provides an in‐depth exploration of metaverses, charting their historical development, technological foundations, and potential multifarious applications. It critically assesses the prevailing challenges and explores potential pathways for the evolution of these expansive, virtual environments. In shedding light on the wide‐ranging implications of metaverses, it navigates societal, cultural, regulatory, and economic landscapes. It further elucidates the symbiosis between the Internet of Things (IoT) and metaverses, presenting empirical evidence derived from purpose‐built IoT frameworks for metaverse applications. A series of experiments were conducted to affirm the hypothesis that the integration of IoT into metaverse utilities, including advanced concepts such as smart buildings, the intricate task of power grid management, and the precision‐centric domain of agriculture, can drive significant progress. Quantitative findings provide compelling evidence of marked improvements in energy conservation, cost‐efficiency, and operational effectiveness arising from the incorporation of IoT into metaverse use cases. With observed mean improvements of 25% in energy conservation, 17% in cost reduction, and an impressive 22% increase in operational efficiency, specifically in the realms of smart building applications and power grid management, this study underscores the pressing need for sustained research and development initiatives in this emerging. [ABSTRACT FROM AUTHOR]

Demand Reduction is a strategy with the potential to make a significant contribution to the energy supply/demand balance. Its two major themes are improving the energy efficiency of devices (appliances and processes) and changing people's behaviour towards using less energy. In our analysis of a nation's energy security, we treat Demand Reduction as an additional fuel which delivers 'negafuel', allowing a particular level of energy services to be met at a lower volume of supply than would be possible in its absence. In common with other fuels, negafuel is delivered by a supply chain with linked stages, all encountering risks of various types. A comprehensive survey of these risks in a case study of the UK shows that Demand Reduction belongs to a middle-ranking group of fuels in terms of overall risk. High-level risks encountered include the difficulty of assessing and delivering potential energy savings, the rate of building construction at the highest energy efficiency standards, optimism bias, changing policy and regulation, and operational failure (both of technology and policy). Assessing the risk of Demand Reduction as a supplied negafuel focuses attention on specific risks requiring mitigation, facilitating design of better policy, and more effective commercial products. [ABSTRACT FROM AUTHOR]

Viologen‐based electrochromic devices have attracted great attention because of their tremendous potential in building energy conservation and low power display. However, the unsatisfactory performance at lower voltage limits their application, while the high driving voltage increases the energy consumption as well as safety risk. Herein, an electrocatalytic strategy is proposed for high‐performance viologen‐based electrochromic devices. Copper oxide (CuOx) nanoparticles are uniformly deposited on the F‐doped Tin Oxide (FTO) glass for enhancing the catalytic activity of Br−/Br3− redox couple, thereby promoting the interfacial charge transfer. The driving voltage can be reduced by ≈30% without sacrificing its high transparency (up to 80%) and the cycling stability can be significantly improved within 200 cycles. Large‐area smart windows and electrochromic displays are fabricated, which can be driven by the 1.5 V dry battery. This work opens up a new path to optimize the electrochromic performance of viologens and also lays the foundation for the application of catalysis in optoelectronic devices. [ABSTRACT FROM AUTHOR]

This study investigates the properties of light transmission and distribution, examining how incident light angles impact illuminance distribution and daylight factor. Light tubes are acknowledged as promising tools to enhance lighting conditions and reduce energy consumption in building design. The study involved installing horizontal hollow light tubes, each measuring 0.5 m in length and 0.30 m in diameter, on a wooden test model. A 20-watt LED lamp was employed as the light source, and an illuminance meter recorded the values at various horizontal and elevation angles. The study's assessment included calculating the average illuminance and daylight factor to obtain light transmission efficiency and energy-saving potential. The findings revealed that both aluminum alloy and zinc alloy tubes experienced a decrease in illuminance as incident elevation angles increased, with the most effective light transmission occurring at a horizontal angle of 90°. Notably, the aluminum alloy tube outperformed the zinc alloy tube, demonstrating more than a 15% increase in light transmission efficiency. Furthermore, the daylight factor values from both types of tubes aligned with established standards for residential and office activities, underscoring their potential as energy-efficient lighting solutions for spaces lacking natural light or with limited illumination. [ABSTRACT FROM AUTHOR]

Novel core-shell nanostructures containing renewable capric acid (CA) core (as a high potential phase change material) and TiO2 (as a highly stable shell) were synthesized using a solgel method for thermal energy storage. Remarkably, CA, a fatty acid available in some vegetable oils, is a renewable phase change material with no undesired environmental impacts. A central composite design of response surface methodology was implemented to determine the effect of the mass ratio of CA/TNBT and the pH value on the encapsulation ratio. As the quadratic mathematical model was used to optimize the process parameters, the maximum encapsulation ratio of 56.67% was achieved, where the CA/TNBT mass ratio was 8.10, and the pH value was 2.65. The measured thermal properties indicated that NEPCMs melt at 31.1 °C with a latent heat of 88.8 J g−1 and solidify at 28.9 °C with a latent heat of 84.23 J g−1. The chemical structure and crystalline phase were measured using Fourier transformation infrared spectroscope and X-ray diffractometer. The thermal stability of the NEPCMs was analyzed by a thermogravimetric analyzer. According to the morphological images, the nanocapsules showed almost spherical shapes with an average size of 100–500 nm. The thermal cycling tests show the high thermal reliability of NEPCMs after the 50th melting/solidifying cycle. The results indicated that the prepared NEPCMs have good thermal stability and reliability for thermal energy storage; hence, they can be applied in building energy conservation and air-conditioning systems. [ABSTRACT FROM AUTHOR]

Urban environments can be turned greener and more sustainable by letting in vegetation. Applying green facades on buildings' vertical surfaces is a viable option that brings various advantages. This study focuses on the energy benefit provided by an evergreen green facade in Mediterranean climate conditions. The results came from a long experimental campaign, heat fluxes evaluation, and statistical analyses. The thermal behaviour of the experimental green facade was analysed all year round, highlighting differences between warm and cold periods and the time of the day. The main advantage was assessed in terms of energy saving, defined as heat flux reduction through the wall covered with vegetation compared to an unvegetated wall. The study pointed out that energy saving was achieved throughout the year, but at different times of the day based on the season. A daytime energy saving was obtained in warm periods due to the shading effect and the plants' evapotranspiration. A night-time benefit was reached in cold periods mainly thanks to the green layer's thermal and wind barrier action. The results showed daily mean energy saving values equal to 11.47 W m-2 for a warm period and 3.23 W m-2 for a cold period. The statistical analysis highlighted that the energy saving was positively influenced by external air temperature, especially in the daytime. Overall, higher energy saving was provided by the green facade when higher external air temperature values were recorded. This research contributes to filling existing literature gaps on the yearly behaviour of green facades and on the energy benefits these provide. [ABSTRACT FROM AUTHOR]

This paper presents the concept of an innovative control of a central heating system in a multifamily building based on the original thermodynamic model, the resulting architecture of the control system, and the originally designed and manufactured wireless temperature sensors for thermal zones. The novelty of this solution is the developed layers of the control system: distributed measurement and correction analysis, which is based on the existing infrastructure and the local HVAC controller. This approach allows for the effective use of the measured temperature data from thermal zones and finally sending the value of the calculated correction of settings to the controller. Moreover, in the analytical layer, a model was also implemented that calculates the necessary amount of energy based on data from the subsystem of temperature sensors located in the thermal zones of the building. The use of the algorithmic strategy presented in this paper extends the functionality and significantly improves the energy efficiency of the existing, classic, reference heating control algorithm by implementing additional control loops. Additionally, it enables integration with demand-side response systems. The presented concept was successfully tested, achieving real energy savings for heating by 12%. These results are described in a case-study format. The authors believe that this concept can be used in other buildings and thus will have a positive impact on the energy savings used to maintain thermal comfort in buildings and significantly reduce CO2 emissions. [ABSTRACT FROM AUTHOR]

In this study, the waste heat loss of flue gases from the boilers of Kafkas University district heating system has been calculated between 6-8% according to the combustion analysis and the annual cost of this heat loss has been found as $58,658.79. In terms of energy efficiency and the national economy, we think that this lost energy should be recovered as much as possible and fuel and energy savings should be achieved. In the paper, the effects of variants such as air excess coefficient, flue gas temperature, boiler capacity and fuel consumption on the heat recovery from flue gas have been presented in detail. The heat recovery scenarios have been presented for reusing this waste energy for space heating, domestic hot water, and preheating combustion air and the applicability of these scenarios has been investigated in terms of thermodynamics and economics. According to the results of the study, in the second scenario examined to cover the domestic hot water need of the guest house building, the energy savings of the scenario can be provided during 20 years of economic life is $122,820.83, and it has the highest savings income among the scenarios. In addition, it is possible to recover approximately 50% of the flue gas loss with thanks to the scenario. On the other hand, the third scenario of heating the boiler combustion air with waste heat is the easiest and most economical scenario because its payback period is only one year, and there are no extra excavation and pipe costs. [ABSTRACT FROM AUTHOR]

Phase change materials (PCMs) are prospective energy materials that are widely applied in building energy conservation, waste heat recovery, infrared stealth technology and solar dynamic power system. The enhancement of heat transfer and leak-proof performance are critical to PCMs. Although geopolymers have been applied in thermal energy storage, meanwhile, hierarchically porous geopolymers have already shown superb performance in various functional applications, to the authors' knowledge, no report concerning the application of hierarchical porous ones have been issued. This paper concerns the preparation of a shape-stabilized composite PCMs, consisting of hierarchically porous kaolinite-based geopolymer (PKG) embedding polyethylene glycol 4000 (PEG4000), which shows promising prospects in thermal energy storage. Optimized porous geopolymer matrices feature high porosity (>83%), combined with high specific surface area (4.7 m2/g) and thermal conductivity (TC, 1.324 W·m−1·K−1). Furthermore, the shape-stabilized composite PCMs show excellent thermal energy storage properties: loading rate of 80.93 wt%, latent heat of 168.80 J g−1 and TC of ∼0.36 W·m−1·K−1 at 20–30 °C, which is 1.64 times of the TC of pure PEG4000. Finally, the photothermal conversion performances of the shape-stabilized composite PCMs were also simulated. [Display omitted] • A hierarchical porous PKG structure was proposed to carry PCMs. • The hierarchical PKG displayed excellent encapsulation properties. • The PKG/PEG shape-stabilized composite PCMs show prominent thermal energy storage properties. • The photothermal conversion effects of shape-stabilized composite PCMs weresimulated. [ABSTRACT FROM AUTHOR]

This research proposes a novel Trombe wall system using direct absorption solar collector based on phase change slurry (DPTW). The dynamic coupling model of the DPTW system is established, and its accuracy is verified. The indoor temperature of the room under heating conditions in January is simulated. Simulation results indicate that the DPTW system has higher indoor thermal comfort. The indoor personnel activity area temperature was within the range of 18.5–24 °C for 148.4 h, which was 167% longer than that of the traditional Trombe wall system (TW). The indoor thermal comfort index PMV is in the range of −0.5∼0.5 for 119.2 h, an increase of 121% compared with the TW system. In addition, the DPTW system reduces the heat load in winter, which is 39% less than that of the TW system in January. The proportion of solar energy utilization is higher, and the solar fraction of the DPTW system can be increased by 45% at lower temperatures. According to the performance of January, the DPTW system is more robust. Therefore, the TW system can be substituted by the DPTW system because the DPTW system can better maintain the indoor temperature and reduce heating energy consumption. [ABSTRACT FROM AUTHOR]

Buildings use a significant percentage of the total energy consumed worldwide. Striving for energy conservation within buildings is of prime concern for researchers. Hence, scientists are aggressively exploring new energy storage and supply methods to reduce exorbitantly fluctuating energy demands and increase the share of renewable energy in building energy consumption. Solar systems that incorporate phase change materials (PCMs) for thermal storage have significant potential to serve in this context. These systems are not yet able to endure the significant energy demands, but they are being continually improved. The aim of this paper is to explore the existing solar PCM systems that are being studied or that are installed for use in indoor heating/cooling. As per the outcome of this systematic review, it has been observed that when coupled with solar thermal energy, the configuration of PCMs can either use passive or active techniques. Passive techniques are usually less efficient and more costly to implement in a building structure, resulting in active heat exchangers being widely implemented with better technical and economic results. At the same time, it has been observed that for most domestic buildings, organic PCMs with phase change temperatures of up to 42 °C and thermal conductivities of up to 0.56 W/m.K are most suitable for integration in solar thermal energy production. Hybrid systems are also commonly used for larger commercial buildings, in which the solar PCM system (SPCMS) provides a fraction of the total load. Additionally, the Stefan number is the most common technical parameter that is used to assess this performance, along with the effective thermal conductivity of the PCM after using enhancement techniques. The key economic indicator is annual savings per year, with most SPCMSs having a payback period of between 6 to 30 years. This review provides designers and researchers with key insights in terms of formulating a basis in the domain of coupling PCMs with solar thermal energy, especially within non-industrial buildings. [ABSTRACT FROM AUTHOR]

Silica aerogel is a nano-porous ultra-light weight aggregate, and its excellent thermal insulation performance has attracted much attention in building energy conservation. However, the hygrothermal properties parameters such as thermal conductivity, water absorption characteristics, moisture distribution, and pore structure of aerogel incorporated cementitious composites (AICs) are unclear and lack for experimental data. The effects of different aerogel contents on the microstructure and thermophysical parameters of cementitious composites were systematically studied based on traditional characterization methods (Fourier transform infrared, scanning electron microscope) and low field NMR technology was used to study the distribution and migration of water of AICs in the pore structure. The result shows that the microstructure, thermal insulation performance, and hydrophobicity of AICs are affected by aerogel content enormously. The water migration in the pore structure of AICs can be divided into four stages: rapid rise stage (0–15 min), slow growth stage (15 min − 1 h), uniform growth stage (1 – 12 h), and stable stage (12 − 24 h). The thermal conductivity decreases significantly (52.72%) with the increase in aerogel. However, the thermal conductivity of AICs increases after seven days of water absorption. [ABSTRACT FROM AUTHOR]