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Passive daytime radiative cooling (PRDC) is a promising technology providing a cooling strategy that radiates heat directly into outer space without additional energy consumption, a crucial consideration in controlling construction energy consumption. However, the preparation of PRDC materials with controlled radiative properties is still challenging because the radiative interface must be maintained in a clean environment. Herein, a densely distributed porous hybrid aerogel with controlled radiative properties was fabricated using the wollastonite and cellulose as building blocks for building energy-saving applications. To do this, the cellulose pulp was obtained by using waste paper as raw material. Then, the hybrid aerogels, comprising paper cellulose and wollastonite particles, were fabricated by combining the acrylic acid polymers (PAA) bonding, freeze drying and vapor deposition modification. The radiative cooling hybrid aerogel exhibits high solar reflectivity (94.6%) and high atmospheric emissivity (95.1%), due to the laminated design of wollastonite randomly dispersed in the radiative hybrid aerogel. The excellent PRDC capability is also proven by outdoor tests where practical temperature difference is ~ 6.3 ℃ and the maximum cooling power of 147.4 Wm−2 under direct sun irradiance. Wettability test infers that the hybrid aerogel has a static water contact angle of 144.07° ± 2°, thereby indicating its hydrophobicity. In addition, based on the Energyplus simulation, the hybrid aerogel exhibits an average annual cooling energy saving of 8% in buildings across China. The excellent radiative cooling and self-cleaning properties of hybrid aerogel make it durable for long-term outdoor PRDC applications. [ABSTRACT FROM AUTHOR]

To promote sustainable economic development in the Belt and Road region of China, reducing carbon emissions is essential. The construction industry is a major contributor to carbon emissions in China. Therefore, studying the dynamic evolution of carbon emissions from the construction industry in this region and its driving factors is of great significance for effectively controlling emissions and achieving China’s carbon peak and carbon neutrality targets. This paper first employs the Slope model, Moran’s I index, and standard deviation ellipse to reveal the spatial-temporal characteristics of carbon emissions from the construction industry, and then applies the geographical detector model to identify the main driving factors of carbon emissions. The results indicate that: (1) From 2006 to 2021, the total carbon emissions showed a fluctuating growth trend, and there were significant differences in emissions among different regions. (2) Carbon emissions in most provinces exhibited a moderate growth trend, and there was significant spatial correlation and aggregation of inter-provincial emissions. Regional carbon emissions from 2006 to 2021 showed a spatial distribution pattern from northeast to southwest, with a weakening trend, and the center of gravity mainly distributed in the east of the region. (3) Labor input, urbanization rate, total output value of the construction industry, degree of opening up, and energy intensity are the main factors influencing the spatial heterogeneity of carbon emissions from the construction industry, and the majority of the interaction types between factors were bivariate enhancement. This study aims to provide theoretical support for policymakers to formulate appropriate policies for building energy conservation and emission reduction. [ABSTRACT FROM AUTHOR]

With the rapid development of the economy, the scale of construction projects in China is gradually expanding. In terms of construction technology, continuous innovation is being made to meet the needs of sustainable development strategies, and green energy conservation technologies have emerged. It has a brand new design concept, and advocates for maximum energy conservation and environmental protection, fundamentally promoting the rational use of resources and space, and preventing the expansion of air and land pollution. First of all, a brief explanation is given on the current development status of green energy conservation technology in this paper. Secondly, through the introduction and analysis of energy conservation technologies and related building cases, the in-depth research on energy conservation measures of buildings is conducted. Finally, the prospects of green energy conservation technologies are proposed based on the current development status in China. This paper has certain reference value for its related engineering and theoretical research. [ABSTRACT FROM AUTHOR]

Nowadays, China's urbanized buildings are prominent, and the building area continues to grow. The study of keeping the temperature of the building walls constant has become an indispensable key standard for building energy conservation. The purpose of this paper is to simulate and study the thermal energy performance of nanomaterial modified fly ash lightweight energy-saving model in prefabricated buildings. In this paper, in the selection of nanomaterial modified fly ash technology, the finite element simulation technology is adopted to study the thermal insulation effect of nanomaterial modified fly ash in building materials, and it also plays a guiding role in the actual work. In the experiment of improving fly ash lightweight and energy-saving wallboard with nanomaterials, we set up two groups of controlled experiments, namely modifying fly ash with traditional materials and modifying fly ash with nanomaterials. By comparing the heat preservation and heat insulation performance of modified energy-saving wall panels in prefabricated buildings. The results show that the nano-material modified fly ash foamed concrete, as 140 mm thick fabricated wall panel, has a good inhibitory effect on temperature transfer in the simulation of heat transfer. Under the condition of air-conditioning heating in winter and cooling in summer, the temperature difference between the inner surface temperature of the wall envelope (16.32 °C in winter and 23.25 °C in summer) and the indoor temperature (15 °C in winter and 23 °C in summer) is less than 3 °C. Therefore, the flyash lightweight energy-saving wallboard modified by nanomaterials can play a role in heat insulation and show good heat insulation characteristics in prefabricated buildings. [ABSTRACT FROM AUTHOR]

Copyright of New Building Materials / Xinxing Jianzhu Cailiao is the property of New Building Materials Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Engineering Management / Gongcheng Guanli Xuebao is the property of Journal of Engineering Management Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Coal‐fired thermal power must be flexible to enable the grid absorption of inconsistent photovoltaic (PV) and wind power. Combined heat and power (CHP) coal‐fired plants are the primary source for district heating systems. This paper uses a 330 MW subcritical CHP unit as an example to carry out the study. With the promotion of building energy efficiency, when the thermal index is reduced to below 20 W/m2, the low‐load operation of CHP can meet the wind power and PV feed‐in demand and guarantee residential heating without the need for flexibility modification. Meanwhile, more renewable energy generation can reduce carbon emissions from the power supply, further contributing to reducing carbon emissions from buildings. The impacts of different envelope parameters and supplementary heat sources on building carbon emissions are also studied. The conclusion shows that the degree of their impact on carbon emissions ranks as ESMs (energy supply modes) > Factor D (infiltration N50) > Factor A (external wall heat transfer coefficient) > Factor C (window heat transfer coefficient) > Factor B (roof heat transfer coefficient). When the building's heating energy consumption gradually decreases, the distributed heat pump unit can replace the coal‐fired boiler to supply the peak heat load demand. In the future, China's district heating systems can be gradually changed from the current CHP and coal‐fired boilers to CHP and distributed heat pumps. [ABSTRACT FROM AUTHOR]

Prefabrication is undergoing significant growth in the building and construction sector in China. Meanwhile, the integrated measurement and reduction solution for energy consumption is quickly becoming an important target of scientific efforts and research, especially in prefabricated buildings. Embedded energy consumption requirements can potentially be reduced during the manufacturing process of prefabricated components: the opportunity for its reduction can be significant. This paper aims to propose a BIM and LCA integrated approach that enables the energy consumption of prefabricated components in the manufacturing stage to be extracted and calculated in order to obtain a clear, precise understanding of the energy consumption management in prefabrication. To enhance the energy consumption description of prefabricated components, this paper clarifies the contents of energy consumption inventory and related calculation formula in raw material extraction and production, material transportation, and factorized production of prefabricated components, respectively. Specifically, considering that current Industry Foundation Classes (IFC) standard does not accommodate entities with energy consumption information or relationships, it applies the IFC extension method to connect the energy consumption inventory with the BIM model. The proposed approach is applied and verified in a case study from China. This study reveals that energy consumption control should be investigated in the element level considering the differences of various prefabricated components' requirements in the manufacturing stage. [ABSTRACT FROM AUTHOR]

Occupant behavior has an important impact on building energy consumption, and the accuracy of an occupant behavior model directly affects the reliability of energy consumption simulation results. Ultra-low energy buildings are crucial to achieving building energy conservation and carbon dioxide reduction in China. In order to effectively promote the development of ultra-low energy buildings in Hot Summer and Cold Winter Climate Zones. where most residents adopt a "part-time, part-space" pattern of intermittent energy use behavior, and to solve the problem of poor indoor thermal environments and the high incremental cost of ultra-low energy, the study described in this paper takes Changsha as an example to carry out a multi-objective optimization study on ultra-low energy housing using a probabilistic behavioral model. On the basis of a probability model representing the residents' actual behavior in Changsha, the optimization objective indicators, key variables and the technology benchmarks for ultra-low energy building were determined, then multi-objective optimization was carried out for a range of energy efficient technologies to obtain the Pareto optimal solutions. The results showed that the set of optimal solutions could reduce energy demand by 50.2 to 60.2% and reduce indoor thermal discomfort time by 3.52–11.09% compared with those of a reference base case, which just meets the requirements of the current design standard for energy efficient domestic buildings. An optimum solution for energy savings and indoor thermal comfort, along with economic costs, was identified, which can assist in decision-making by providing different preferences and provide useful reference for the design of ultra-low energy buildings in Hot Summer and Cold Winter Climate regions. [ABSTRACT FROM AUTHOR]

Global climate crises are forcing the world to behave sustainably. The building energy service industry (BESI) emerged and promoted building energy conservation by providing a market-oriented mechanism for initial investment. However, the BESI lacks scientific and rational planning, lagging far behind the energy service in the industrial sector. This paper attempts to analyze BESI from the perspective of order parameter-based analysis by adopting the DEMATEL (Decision-Making and Trial Evaluation Laboratory) method, thereby revealing the characteristics of industrial evolution and ascertaining the main order parameters. Consequently, the results show that the evolution of the BESI industry relies on synergistic interaction in the corporate operation, industry-standard, production factor-related, and external environmental industry subsystems. The synergy of the BESI consists of synergy in subsystems, between subsystems, and between the system and the external environment. Three main order parameters dominating the evolution of the BESIs system are determined, namely, "financial support", "industry standard", and "technology innovation". Financial support and industry standard drove the development of the BESI in China over the last few years, while technological innovation will lead its evolution in the coming years. Based on these results, policy suggestions can be proposed to foster BESI development, especially regarding technological innovation. [ABSTRACT FROM AUTHOR]

ICT has significantly transformed the traditional energy production and service methods, changed the correlation characteristics of energy consumption network, and contributed to the establishment of cross-regional, open, and synergistic energy ecological networks. In this paper, social network analysis (SNA), dynamic SYS-GMM model, and mediating effects model are employed to deliberate on the mechanism of ICT capital's influence on the spatial correlation of energy consumption from 2000 to 2019. Firstly, this study employs an enhanced gravity model to precisely delineate the spatial correlation network of energy consumption in China, further applies the SNA to analyze the network structural characteristics, and then uses the econometric model to investigate the influence mechanism and heterogeneity of ICT capital on the spatial correlation of energy consumption. The study demonstrates a progressive spatial correlation in energy consumption in China, with eastern provinces emerge as the center of the network, assuming the position of the "dominant player." Conversely, the central provinces act as the "bridge," and western provinces are positioned at the periphery, referred to as the "edge" of the network. ICT capital contributes to improving the energy consumption spatial correlation, mainly by stimulating green technology innovation, promoting industrial structure optimization, accelerating human capital accumulation, and reducing income inequality. As ICT capital expands, the eastern region becomes more preeminent as a network hub for energy consumption, the central region increases its dominance slightly, and the western region's marginal position does not change significantly. Furthermore, the presence of ICT capital significantly enhances the intensity of energy consumption spatial correlation more prominently for low-carbon pilot areas and high Internet level areas. This study guides provinces to fully utilize ICT capital to reach collaborative energy-saving goals, and promotes the breaking down of regional competitive barriers in energy systems to build cooperative energy conservation ecological networks. [ABSTRACT FROM AUTHOR]

LVDC buildings use a low-voltage direct current (LVDC) distribution system for energy transmission and integrate photovoltaic (PV), battery energy storage (BES) and the utility grid as building energy resources. This technology can reduce energy loss in conversion to a certain extent and increase renewable energy compared with traditional AC distribution systems. Under the national goal of carbon peaking and carbon neutrality, LVDC buildings have been proven to be a new approach to energy conservation and emission reductions, and have been applied in engineering in China. However, the construction methods and integrated technologies of those projects are not clear, and technical barriers and policy constraints for the engineering application of LVDC buildings are not systematically discussed yet. This paper presents the latest study of LVDC building engineering applications the advantages and drawbacks of LVDC development in China. First, relevant policies and standards which support the development of LVDC building industries are summarized. More than 60 practical LVDC projects are investigated, and the application characteristics and the technology status of building types, and their capacity and design methods, etc., are analyzed. The attitudes of stakeholders toward LVDC buildings are surveyed to determine the policy direction according to the demands of this technology, with reference to building practitioners who intend to engage in LVDC projects. [ABSTRACT FROM AUTHOR]

In order to achieve China's energy conservation and emission reduction goal of peaking carbon dioxide emissions around 2030, it is of great significance. An important means of building energy conservation and emission reduction is the fine management of building energy consumption, which is based on the accurate prediction of building energy consumption, so as to support the optimal management of building operation and achieve the goal of energy conservation and emission reduction. This paper puts forward the evaluation indexes of the results of the building energy consumption prediction model, uses MAPE and RMSE indexes to evaluate the accuracy of the prediction results of the model, and uses the prediction time and input parameter dimensions to evaluate the time cost of the prediction model. Then, using the three building energy consumption prediction models based on machine learning algorithm established above, the prediction of energy consumption of four types of public buildings in different seasons is completed, and the prediction results are evaluated and analyzed. According to the prediction results and the requirements of related work on the accuracy of building energy consumption prediction model, the adaptation relationship between different types of buildings and different machine learning algorithm prediction models is summarized. [ABSTRACT FROM AUTHOR]

Under the requirement of energy savings and emission reduction in China, building energy consumption, which occupies a rising proportion of the total energy consumption in society, has become the focus of energy conservation research. Public buildings with a high-energy consumption level have become the most important part of energy conservation research. It is of great practical significance and social value to study energy conservation in large public buildings. In this paper, a large office building is taken as an example. First, a simulation model is constructed by using the energy consumption simulation analysis method, and the reliability of the model is verified by a comparison with the actual energy consumption. Second, based on the model, the thermal design parameters of six building envelope structures, including the external wall heat transfer coefficient, are analyzed in the order of energy-saving sensitivity. Based on the results of the sensitivity analysis, suggestions for each factor are presented. Finally, considering the mutual influence of each parameter on the building energy consumption, the orthogonal design method is used to arrange the test, and the optimal scheme combination of the energy-saving effect is analyzed, which can provide decision support for the energy saving of public building envelopes. [ABSTRACT FROM AUTHOR]

Copyright of South Architecture / Nanfang Jianzhu is the property of South Architecture Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Energy consumption monitoring technology plays a very important role in the realization of intelligent building energy saving, but it is not accepted widely in China. The main reasons for this are the low public energy-saving awareness and incomplete informational policy instruments; thus, studying how informational policy instruments affect the adoption of energy consumption monitoring technology and the impact of energy-saving awareness is of great significance to the widespread acceptance of energy consumption monitoring technology and its role in the realization of intelligent building energy saving. This paper introduces informational policy instruments and energy-saving awareness into technology acceptance model and builds an extended technology acceptance model. A questionnaire survey of 298 respondents who related to the operation and management of public buildings was used to explore the effect mechanism of informational policy instruments on adopting energy consumption monitoring technology. The results show that (1) informational policy instruments have no direct impact on the acceptance of energy consumption monitoring technology (2) and energy-saving awareness, attitudes, perceived usefulness, and perceived ease of use can mediate the relationship between informational policy instruments and behavioral intention of adopting energy consumption monitoring technology, namely, informational policy instruments can affect behavioral intention through six paths which are informational policy instruments ➔ energy-saving awareness ➔ behavioral intention, informational policy instruments ➔ energy-saving awareness ➔ attitudes ➔ behavioral intention, informational policy instruments ➔ attitudes ➔ behavioral intention, informational policy instruments ➔ perceived ease of use ➔ behavioral intention, informational policy instruments ➔ perceived ease of use ➔ perceived usefulness ➔ behavioral intention, informational policy instruments ➔ perceived usefulness ➔ behavioral intention. Finally, relevant policies and suggestions are put forward based on the results. [ABSTRACT FROM AUTHOR]

China is facing the challenge of high building energy consumption, especially for rural housing, because of the backward construction technology. This issue could be solved by net-zero energy rural housing. Therefore, the passive energy-saving procedures and energy-efficient building service systems of rural housing are needed to be studied apart from renewable energy adoption. Older people with unique thermal acceptability and adaptability become the primary residents in Chinese rural buildings, which calls for the redefinition of the indoor environment. This paper firstly conducted an overall questionnaire about the indoor environment sensation and expectations of the rural elderly in Sichuan province. Field surveys and measurements were carried out in a typical self-built rural house to investigate the thermal comfort of the local order people and the indoor thermal environment variations. Furthermore, the fuzzy analytic hierarchy process was used to propose a three-layer assessment model for the rural elderly living environment to find retrofit strategies. Results showed that: (1) the thermal environment of rural buildings could not meet the thermal comfort range of older people in summer. (2) The adaptive coefficient (λ) in the adaptive Predicted Mean Vote model was 0.065 for the rural elderly, which was lower than the value of 0.21 in the Chinese standard, indicating their poor thermal adaptability. (3) The summer living environment evaluation was "A little bad", and the most effective optimization method was to decrease the indoor temperature. (4) Based on the thermal comfort of older people, architectural and construction optimizations were proposed, which could achieve an energy-saving of 52.15 %, contributing to net-zero energy rural housing. • Environment improvement and energy saving of rural housing were studied. • The age-based metabolic rate of the elderly was proposed in aPMV. • The adaptive coefficient for the rural elderly was 0.065. • The evaluation model of rural living environment satisfaction was built by FAHP. • Passive retrofit procedures were proposed to achieve NZERH. [ABSTRACT FROM AUTHOR]

An enormous amount of investment has been spent towards informatization for the construction industrialization engineering, procurement, and construction (EPC) enterprises in China; however, the performance output remains uncertain. This paper aims to evaluate the informatization performance of the construction industrialization enterprises in China based on a proposed evaluation framework. The proposed framework entails a hierarchical input and output structure; the input metrics include 4 first-level and 17 second-level indicators, and the outputs include 6 first-level and 27 second-level indicators as the metrics, respectively. Survey and interview are utilized to collect data, with effective responses from thirty construction industrialization EPC enterprises. The informatization performance of these enterprises is evaluated using an improved D-FCA method, which incorporates the analytic hierarchy process (AHP), data envelopment analysis (DEA), and fuzzy comprehensive evaluation analysis (FCA). The research results indicate that all the surveyed enterprises meet the performance requirement, and 60% of the thirty enterprises show excellent performance, reaching A level, AA level, and AAA level. Furthermore, for those enterprises with DEA scores less than 1, which indicates inefficient use of the resources during the informatization process, strategies are proposed to improve the performance of these enterprises. This study contributes a comprehensive framework to evaluate the informatization performance of construction industrialization enterprises in China. The enterprises studied currently mainly come from some developed areas, and the overall situation for construction industrialization needs to be further studied in future research. [ABSTRACT FROM AUTHOR]

The construction industry of China is characterized by its huge consumption and carbon emissions, thereby making this industry one of the most important areas that require energy conservation efforts. Identifying those factors that affect carbon emissions in the construction industry carries great significance in reducing building carbon emissions, promoting low-carbon cities, and achieving China’s emission reduction goals. This paper firstly reviews the literature on those factors that affect the carbon emissions in the construction industries of developed countries. Second, by using Henan Province as an example, those factors that influence carbon emissions are measured by using the classical STIRPAT (Stochastic Impacts by Regression on Population, Affluence and Technology) model. Third, some measures for reducing carbon emissions in the construction industry are developed. Those factors that influence the carbon emissions of buildings are multi-dimensional and diversified. Resident population, urbanization rate, building carbon emission intensity, per capita GDP (Gross Domestic Product), and per capita added value of the tertiary industry all have significant effects on the carbon emissions of buildings in Henan Province. Some policy suggestions can be derived from the findings of this work, such as encouraging building energy conservation, improving the energy efficiency of the construction industry, adjusting the use of building materials, and improving the extant policies for building emission reduction. The results also provide a theoretical basis for identifying those factors that affect the carbon emissions in the construction industry and for formulating and implementing strategies for the low-carbon development of this industry. [ABSTRACT FROM AUTHOR]

Copyright of Guangdong Architecture Civil Engineering is the property of Guangdong Architecture Civil Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Harbin Institute of Technology. Social Sciences Edition / Haerbin Gongye Daxue Xuebao. Shehui Kexue Ban is the property of Harbin Institute of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this paper, the green roof of the California Academy of Sciences was selected for example to illustrate the role of green roofs in sustainable urban planning from three aspects: landscape connection, building energy conservation and urban environment and elaborate the innovative design elements of the California Academy of Sciences, and the enlightenment of green roofs on the construction of sponge cities in China and the guiding role for future urban design were analyzed combined with the current urban problems in China and the research status of green roofs at home and abroad. [ABSTRACT FROM AUTHOR]

When modeling the energy performance of existing buildings, model calibration always serves as an essential and necessary step to ensure the accuracy and applicability of building models. Model calibration for detailed energy models, which is also known as calibrated simulation (CS), refers to the process of tuning model's input parameters to narrow down the mismatch between the simulation result and the real-monitored data of building energy consumptions. Two major problems of current CS are: (1) a successful calibration requires HVAC domain knowledge of modelers. (2) Traditional building calibration process is labor-intensive and time-consuming. To solve these problems, a normative energy modeling based quick auto-calibration approach is proposed in this study. This approach is able to reduce the modeling time and simplify the calibration procedures. Firstly, this paper demonstrates the working principles and the credibility of Normative Energy Modeling (NEM). Then, the methodology of the proposed quick auto-calibration approach is elaborated. The energy performance model of a large hotel located in Shanghai, China with NEM is used as a case study to investigate the effectiveness of the proposed quick auto-calibration approach. The simulation result of the case study suggests that the proposed approach can significantly simplify the procedures of model calibrations while still achieve a good accuracy specified by ASHRAE Guideline 14 [1]. Besides, the results further confirm that such method requires much less time and computational power for modeling, compared with other counterparts (e.g., “Autotune” calibration [2]). With the advantage of speed and accuracy, the auto-calibration proposed in this paper is promising to be applied in both engineering and research field. [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]

• The low-carbon technologies (LCT) in realizing urban carbon neutrality are reviewed. • More than 150 papers with high citation rates are selected for specific analysis. • Three main aspects are investigated: LCT, ECER and CCSU. • Building energy consumption is a huge carbon emitter and poses a challenge for SUD. This work aims to study the role and current situation of Low-Carbon Technology (LCT) in realizing urban Carbon Neutrality goals and Sustainable Urban Development (SUD). This work focuses on the three main aspects of Carbon Neutrality by means of investigation: the new energy-supported LCTs, building-oriented Energy Conservation and Emission Reduction (ECER), and Carbon Capture, Storage, and Utilization (CCSU) technology. The research of the past ten years (2013–2022) is reviewed from the Web of Science, Google Academic, and other literature databases. Over 20,000 articles are selected by using the keywords "Carbon Neutrality Technology," such as "IEEE," "Elsevier," and other journal documents. Finally, more than 150 papers with high citation rates and relatively novel research results are selected for specific analysis. This work also establishes a case study of urban green development with multiple co-governance and a case study of building energy conservation and carbon reduction solutions. Finally, suggestions are put forward for achieving SUD. China's energy consumption and Carbon Dioxide (CO 2) emissions have increased year by year, but the Carbon Peak has not yet been reached. About 85% of CCUS technologies extract CO 2 from the air and use it for other emission reduction processes. In addition, the carbon storage time and storage efficiency need to be improved, and the general level can only reach about 60% of the storage efficiency. The secondary use of CO 2 by technology is of practical significance to many industries and must be fully implemented from the perspective of the whole life cycle. Especially building energy consumption is a huge carbon emitter and poses a challenge for SUD. How to take effective measures to control emissions is still an arduous task [ABSTRACT FROM AUTHOR]

Ground source heat pump system has been widely utilized in office buildings in China. Its application in nearly zero energy office building pioneers an innovation in China. This paper focuses on real operation introduction and performance analysis of a Ground Source Heat Pump (GSHP) system in a nearly zero energy building (NZEB) with different HVAC terminal for the first time. The paper introduces the nearly zero energy building with a general presentation of its energy system, then analyzes GSHP system operation and soil temperature variation from November 2014 to September 2015 based on real operation data. The analyses manifests that the HP2# worked under an average COP of about 5.4 and 5.0 in summer and winter, respectively and HP1# worked under an average COP of 3.9 and 3.0 in winter and summer respectively. In the winter season floor and ceiling radiation system has a relatively higher performance than radiator system due to low supply water temperature going into the room. Room temperature keeps above 20 °C in the winter season and fluctuated around 26 °C in the summer season. Good room temperature and COP proves the GSHP system functions excellently. Soil temperature could recover in one year operation. [ABSTRACT FROM AUTHOR]

In this paper, a saving to investment ratio (SIR) method was used to determine the key prescriptive parameters for upgrading the building energy code with different energy reduction ratio requirements, including the U value of walls, roofs and windows; as well as a consideration of the efficiency of boilers and coefficient of performance of water chillers. An economic model for single typical energy saving technologies was established and the relationship between the incremental cost and the payback period of the different technologies was analysed; then the baseline building model was optimized by these measures in descending order according to the SIR methodology. The model method (SIR) was then applied to case studies in four climate regions of China. A large office reference building situated in Harbin, Beijing, Shanghai and Guangzhou in climate zones from north to south of China was analysed as examples to showcase the relationship between the building energy saving ratio and the incremental cost. The key prescriptive parameter requirements of walls, roofs, windows, chillers and boilers with 5% and 10% energy saving ratios were defined separately for these buildings. [ABSTRACT FROM AUTHOR]

Facing the challage of energy conservation and emission reduction in the building sector, most energy saving strategies of central heating only focus on the performance improvement of building envelope, ignoring the impact of energy use behavior. This paper proposed a building energy conservation strategy based on energy use behavior analysis, which provides a perspective for in-depth exploration of building energy conservation. After investigating a typical university in the northern China, the energy use behaviors were characterized and two different DeST energy consumption models before or after considering energy use behavior were established. By comparing the results calculated by these two models, the impact of energy use behavior analysis on building energy consumption was quantitatively analyzed. The results show that the heating energy consumption and carbon emission can be reduced by 23.28% and 23% respectively through the proposed strategy based on energy use behavior. Therefore, the analysis of energy use behavior can provide a theoretical basis for heating operators to make decisions on energy supply regulation. With central cooling and heating further popularizing in the future, the research methodology of this paper has more extensive reference value for energy conservation and emission reduction strategies in the building sector. [ABSTRACT FROM AUTHOR]

Abstracts Energy conservation and emission reduction issues in the construction phase of buildings are increasingly important to meet the challenges of sustainable building. Technological advancement is considered as one of the essential driving forces for green and sustainable construction. But, it is not as effective as expected because the anticipated energy conservation from efficiency improvement would be partially or even totally offset if energy rebound effect exists. This paper fills the research gap by quantitatively investigating the impacts of technological advancement on energy consumption in China’s building construction industry by incorporating direct rebound effect. First, technological advancement rate in terms of energy efficiency is measured by constructing an energy-environmental non-radial directional distance function (ENNDF), which provides a strong support for the Porter hypothesis. Second, by incorporating asymmetric energy price decomposition into a framework of translog cost function, it is estimated that 21.8% energy savings from energy efficiency improvement in China’s construction industry are offset due to rebound effect. Based on the measured results of technological advancement rate and rebound effect, further counterfactual analyses find that technological advancement contributes 27.11 million tons of standard coal equivalent (Mtce) of energy conservation for the construction industry over the period 2003–2012, and 7.57 Mtce of energy would have been saved in the sector if there were no rebound effect. Empirical findings in this paper reveal that technological innovation as well as energy pricing reforms, tax policies and other environmental regulations should be further implemented to achieve effective energy conservation for green building construction. [ABSTRACT FROM AUTHOR]

At this critical junction of industrialization, China is facing an increasingly prominent imbalance between energy supply and demand. It is of great social significance to study the energy-saving of buildings that consume a huge amount of energy. For most heating systems, energy waste mainly arises from inefficient operations of boilers, low efficiency of pipe transmission, and poor quality of heat supply. This paper researches and evaluates the energy-saving reconstruction of intelligent community heating (ICH) system based on the Internet of things (IoT). Firstly, the energy-saving reconstruction of the ICH system was analyzed, and a hydraulic regime model was derived from the simplified model of the water supply and return pipe networks. Then, the system pipe network was investigated in three aspects, namely, node flow balance, pipeline pressure drop balance, and loop pressure drop balance. On this basis, the authors presented the balance equation and finalized the hydraulic regime model of the system. After that, the energy consumption of the system was evaluated before and after the reconstruction, and the energy-saving benefit was predicted. The effectiveness of the proposed method was proved through experiments. [ABSTRACT FROM AUTHOR]

Construction of conserving campus is necessary to achieve sustainable development. Taking North China University Of Science and Technology for example, this paper proposes systematically how to launch subjects of actual measurement and simulation of energy consumption and the analysis of energy-saving for the energy consumption of campus. On the basis of analysis of the college typical building energy consumption, this paper tests the illumination, noise and formaldehyde concentration of Yifu Library, gives a detailed analysis of the measurement data, and provides the basis for energy saving transformation, operation management and updating equipment.By using a building energy consumption simulation software-eQUEST to simulate and research the energy consumption of Yifu Library, and collecting and collating the 2012-2013 annual water, electricity and gas usage to analyze the above energy data, and obtain the current status and characteristics of campus energy consumption. Finally, by comparing the measured and simulated results, it shows that universities present tremendous potential for energy savings. Therefore, from energy conservation of the technology, management and behavior, the reasonable energy-saving reconstruction measures are put forward. [ABSTRACT FROM AUTHOR]

• Proposed hybrid system incorporates a fresh air conditioner with refrigerant system. • Fresh air conditioner has a heat-exchanger network for two-stage energy recovery. • Four independent affecting parameters are included for parametric analysis. • Optimum air-water heat capacity ratio of packed tower is found to be between 0.4–0.6. • Average energy-saving rate of the proposed hybrid system is 44.0%. Energy recovery technologies can effectively improve the energy efficiency of air-conditioning systems and significantly reduce building energy consumption. In this paper, a parametric analysis and energy-saving potential evaluation for a new hybrid air conditioning system (HAC) is carried out theoretically based on developed models. The proposed HAC incorporates into a conventional mechanical vapor compression air conditioning system with an independent fresh air conditioner which is composed of a network of heat exchangers, including a packed bed and three air-water finned coils. Under cold winter climate, in the fresh air conditioner, a packed bed is coupled with a water-air heat exchange coil to form a total energy recovery loop. A run-around sensible energy recovery loop is also integrated in the system to produce a two-stage energy recovery effect. Moreover, a sprayer is installed upstream of the two-stage energy recovery process for fresh air humidification, and a fresh air recirculation duct is equipped for frost-free operation. In the parametric analysis, four independent affecting parameters are included: the air-to-water heat capacity ratio, the indoor temperature, the ambient temperature, and the ratio of recirculation fresh air. The energy-saving potential of the HAC is also evaluated for applications in seven typical cities located in middle-lower Yangtze River region of China over the winter period (December, January and February). The results show that compared with the conventional system with electric humidification, the HAC has an average energy saving rate of 44.0%, and its average power saving per hour is 13.41 W m−2. [ABSTRACT FROM AUTHOR]

The ultra-low-energy (ULE) passive buildings are an important trend of building energy conservation. China has been steadily pushing forward energy-saving policies for buildings, and started to promote the ULE passive buildings. Solar heating has a great application potential in the ULE passive buildings, which are required to consume a very low amount of energy. This paper establishes a simplified model of slab-type residential unit in cold regions of northern China, and correlates the areas of solar heating available on the south wall and the roof with the heating loss of the building, according to the change law of solar radiation. In addition, the calculation formulas for wall and roof heating factors were proposed under the ULE condition, and applied to compute the heating factors of major cities in northern China. The calculation results verify the effectiveness of the formulas. Through statistical analysis, it is learned that wall and roof heating factors are closely correlated with the regional latitude. Hence, the relationship between them were fitted, and verified by a case study in Shijiazhuang, China. The fitted relationship was proved correct, laying the basis for fast and accurate evaluation of solar heating potential in cold regions. [ABSTRACT FROM AUTHOR]

• Obtaining the optimal interpolation method for adjacent sites. • Proposing the method for revising meteorological data at city scale. • Verifying the accuracy of the method by energy consumption simulation. In the development process of building energy conservation design, the correct provision of local Typical Meteorological Year (TMY) data is a prerequisite and basic work to evaluate building energy consumption, which directly affects the fine use of outdoor data for building energy conservation. Based on the recorded and observed data of meteorological stations in China, the acquisition and correction methods of TMY were studied by mathematical statistics and target searching, and the building energy consumption simulation of urban office buildings was conducted to verify the accuracy of the method, including:(1) Reviewed the generation method for TMY and the acquisition of data.(2) Based on the existing TMY data, the best spatial interpolation method of adjacent stations is studied by using the standard deviation method, and the selection method of the best number of stations on a large regional scale is given.(3) An improved method of urban environment TMY is proposed. The dry bulb temperature and relative humidity of the building site are corrected to generate TMY under Urban Heat Island (UHI) effect. The research in this paper improves the coverage and accuracy of urban TMY data and supplies basic research support for building energy-saving designs. [ABSTRACT FROM AUTHOR]

The environmental and energy crisis has become a problem that can not be ignored in today's world and improving the proportion of renewable energy utilization is an important way to alleviate the problem. China has begun to vigorously develop rooftop photovoltaic systems, and it is urgent to analyze the photovoltaic potential of the country. In this paper, GIS technology is used to calculate the available area of a PV system on the roof of urban buildings in China. The installed capacity and annual power generation of a PV system on the roof of urban buildings in China are further calculated, and the investment cost analysis of the buildings with a PV system is carried out. The results show that Chinese mainland city rooftop photovoltaic area has reached 3.35 billion m2. If urban roofs are used for photovoltaic power generation in China, the annual photovoltaic power generation capacity will be 672 billion kWh, which is about 61% of the total annual electricity consumption of the whole society in 2020. On the other hand, the initial investment in the construction of an urban photovoltaic system is large, but most of them can realize the return of investment in a short period of 8–10 years. Moreover, in the effective life of the follow-up photovoltaic system, it will bring greater economic benefits, which is more than two times the initial investment. To further promote the process of social carbon peak and carbon neutrality in China, the construction of an urban photovoltaic system is very feasible. [ABSTRACT FROM AUTHOR]

Highlights • The first city-level building energy efficiency benchmarking system for China. • A model considering the influence of operation parameters on energy consumption. • A systematic methodology of building energy benchmarking is proposed. • The model is a valuable analysis support tool for building energy managers. Abstract The city-level public building energy efficiency benchmarking system has an important guiding value for building energy-saving work, especially for Beijing, with its high energy-consumption density and both long heating and air-conditioning periods. This paper analyzed the characteristics of large-scale office buildings in Beijing and gives a detailed description of the process of establishing a public building energy efficiency benchmarking system for large-scale office buildings in Beijing, China, including data investigation and verification, Energy Usage Intensity(EUI) calculation, determining independent and dependent variables, developing and testing the benchmarking model, and deriving the benchmarking rating table. Then the first city-level public office building energy efficiency benchmarking system in China is established based on 88 large-scale office buildings in Beijing. The results showed that the model's performance index R2 is 0.667 and gives a good representation. The process has a strong potential for replication for other cities in China and even for a national energy-consumption evaluation system. [ABSTRACT FROM AUTHOR]

The aims of the paper were to clarify whether office buildings in the severe cold and cold regions are overheating, especially those with natural ventilation, and whether potential overheating is related to the building materials. The severe cold and cold regions of China were considered to be cool regions during summer. However, with global warming, improvements in the thermal performance of the building envelope and the urban heat island effect, office buildings in these regions are showing different degrees of overheating during summer. Two office building materials commonly used in this area, cross laminated timber (CLT) and concrete block, were simulated in this study. With reference to the overheating standard, the degree of overheating in six cities in the severe cold and cold regions was quantitatively analysed and the extent of overheating for the two building materials was compared. Finally, the influence of thermal insulation on building overheating is discussed, and some suggestions are put forward to improve the relevant national regulations in China. The results show that office buildings in the severe cold and cold regions experience overheating during summer, and CLT buildings are more prone to overheating than concrete buildings during summer. This is attributable to the different thermal mass of the materials. Thick insulation does increase the risk of building overheating, and the effect on concrete buildings is more pronounced. Concrete buildings with an insulation layer can experience overheating for 27–71 h more than buildings without an insulation layer. Insulation on CLT buildings only results in an increase of 11–37 h. When considering the current situation with summer overheating in the severe cold and cold regions, relevant codes should also be modified and improved accordingly to guide building design, so as to achieve low-carbon and energy-saving goals. [ABSTRACT FROM AUTHOR]

• In recent years, China's economy has continued to grow rapidly, but the consequent shortage of resources has become more and more serious, and the natural environment problems have become increasingly prominent. Solving the contradiction between people and the environment and realizing the sustainable development of the economy has become an urgent problem to be solved. • The purpose of this article is to study an integrated energy pipeline system based on the Internet of Things technology. Based on the actual data of a university, this paper establishes a predictive model to predict energy consumption, so as to better plan for energy conservation. Based on the theoretical foundation of the Internet of Things technology, combined with the current mainstream technology, Windows + Apache + MySQL + PHP is the development environment, the ThinkPHP framework is the development framework, and an integrated energy data query and energy trend analysis management system. The platform integrates system login, energy consumption data query, historical energy consumption and energy consumption trend analysis, energy saving report, and provides security and expandable functions. • The research results show that although the integrated energy management system studied in this paper has the functions of energy consumption data collection and energy consumption data analysis, it still needs to further optimize the system functions. The research and development of this system has laid the foundation for the field of campus building energy conservation. To achieve more comprehensive functions, better performance and can be applied to the management system of various buildings, the research work needs to be further improved. In recent years, China's economy continues to develop at a high speed, but also faces the enormous pressure of energy shortage and environmental deterioration. As an energy-saving discipline, we should actively adopt advanced energy-saving management methods and technologies for energy utilization management. The purpose of this paper is to study an integrated energy pipeline system based on Internet of things technology. In this paper, the actual data of a university is used to establish a prediction model to predict energy consumption, so as to better carry out energy-saving planning. Based on the theoretical basis of Internet of things technology, combined with the current mainstream technology, windows + Apache + MySQL + PHP as the development environment, ThinkPHP framework as the development framework, and a set of integrated energy data query and energy trend analysis management system. The platform integrates system login, energy consumption data query, historical energy consumption and energy consumption trend analysis, Energy saving report, and provide security and scalable features. The system test shows that the performance of the system designed in this paper is stable and can meet the actual needs. In this paper, four groups of different number of users are simulated. The average response time is less than 5S, and the CPU utilization is less than 70 %. [ABSTRACT FROM AUTHOR]

In order to resolve the contradiction between the lack of building energy data and the need of more detailed information about energy performance, this paper presents a simplified building energy performance diagnosis method which can assess the energy performance from building level to system level with only limited information. Based on multiple-parameter regression between the whole building energy bills and outdoor weather data, the proposed diagnosis method uses the regression coefficients to identify the energy use of main systems (i.e., lighting-plug system and cooling/heating system), as well as other detailed information about physical properties of the building and cooling/heating system (i.e., cooling or heating load, the operation of cooling/heating system and the efficiency of cooling/heating system). One case study was conducted in an office building in China to test the application of this diagnosis method. In addition, the regression result of simulated energy consumption served as benchmark data to further diagnose the performance gap between the operation stage and the design stage and help locate the poor performance and key points of energy-saving. Finally, all diagnosis results have been verified by the performance data from advanced energy consumption monitoring system together with field surveys and measurements. [ABSTRACT FROM AUTHOR]

Building Information Modeling (BIM) is regarded as a potential vehicle to tremendously improve the information flow throughout the life cycle of a building. The integration of BIM and Life Cycle Assessment (LCA) has potential to reduce the time for life cycle inventory, and at the same time, substantially improve the representativeness of the LCA results for the specific building design. The latter merit is not trivial. For instance, due to time limit, most building LCA studies estimate the building materials and fuels consumed in construction phase quite roughly, which excludes the choices on a wide range of construction techniques, materials, specialties and machines, no need to mention the energy consumption in operation phase, which is usually estimated in an even bolder manner. The roughness of the LCA practice undermines its credibility and hinders its application as a decision supporting tool for low carbon design. Currently, China's Architecture, Engineering and Construction (AEC) sector is undergoing a smart transformation, steered by the increased use of BIM. This paper presents a BIM-enabled LCA method and illustrates how the method can be used to facilitate the low carbon design under the circumstance of the smart AEC transition in China. A case study on carbon footprint accounting for a residential building is conducted. In this study, various software tools and data sources are combined to enhance the data flow and interoperability between BIM models and LCA models. BIM tools are used to create the BIM model, calculate the inputs (materials, construction machines, energies, water and so on) of on-site construction process and simulate the energy consumption of building operation. The eBalance, a China's local LCA software tool is applied to build the LCA model. The Chinese Life Cycle Database is used as the main data source (72.73%) to calculate the carbon footprint of the given building while the Ecoinvent database and European Life Cycle Database act as supplementary. The results show that the carbon footprint of the building is 2993 kg CO 2 eq/m 2 . The operation phase contributes to 69% of the total greenhouse gas (GHG) emission, while the building material production contributes to 24%. Concrete is the most used building material, which accounts for 82% of mass but contributes to only 44% of the material related GHG emission. Although steel and aluminum account for only 2.6% and 1.4% of mass, they contribute to 28% and 17% GHG emission, respectively. Through BIM-enable LCA modeling, the potential life cycle environmental performance of the buildings can be assessed in detail. This makes the LCA not only more accessible but also more credible for the AEC professionals to use it as a guide for the low carbon design of buildings. [ABSTRACT FROM AUTHOR]

Vertical greening system(VGS) for buildings is drawing more and more research, because that it provides passive cooling for both indoors and outdoors without occupying valuable urban land, and thus can be a remedy for the deteriorating thermal environment of today’s high density urban areas. This paper reports an investigation on the summertime cooling performance of double-skin green facade (DSGF) of a recently-renovated 5-storey administrative building in a university campus in Shanghai. The results show that, the VGS created a distinctive microclimate in the cavity: air temperature T a averagely dropped by about 0.4 °C in a daily circle, and maximally 5.5 °C for the Southern facade; and by 0.2 °C in average and 3.3 °C maximally for the Northern facade. The mean exterior surface temperature T s reduction of the Southern facade by the VGS is 1.5 °C and maximally ∼9 °C, whereas the mean interior T s reduction is 1.2 °C and maximally 2 °C. The corresponding figures of the Northern facade is 0.5 °C, 4.2 °C, 0.5 °C and 1.3 °C, respectively. The indoor thermal improvement by the VGS, evaluated by operative temperature (T op ), is 1.1 °C averagely and 2.7 °C maximally on the South-facing office, and 0.6 °C averagely and 1.9 °C maximally on the North-facing office. The initial findings suggest clear potential of VGS in thermal comfort improvement and cooling energy saving, further study is needed to evaluate the yearly energy and comfort effects of VGS on radiation, convective and conduction heat transfer and on daylighting through building envelop, for comprehensive energy assessment considering cooling, heating and artificial lighting. [ABSTRACT FROM AUTHOR]

This paper proposed a hybrid Logarithmic Mean Divisia Index (LMDI) model that decomposes the change of total energy consumption (TEC) in the building sector to three different dimensions: 1) key influencing effects that include area effect, structure effect, population intensity, value intensity, and energy intensity; 2) three phases that include material production, construction, and operation; and 3) geographically distributed regions. Then, the model was validated in China's building sector based on the data collected from 30 provinces during 2007–2015. The key findings show that: (1) the increased final energy consumption in the building industry accounted for 53.3% of that in China. (2) Building material production contributed the most (69.2%) to the energy changes, followed by building operation (29.6%) and construction (1.2%). (3) The change of TEC was attributed the most to the area effect (90.4%) and the energy intensity effect (42.4%). (4) Zhejiang, Jiangsu, Hubei, Hebei, Fujian and Shandong contributed the most (47%) to the increase of China's building energy use. These findings provide an insightful understanding of the building energy changes and also a quantifiable justification for making building-specific energy policies, which are discussed at the end of the study. [ABSTRACT FROM AUTHOR]

Low-concentration PV (CPV, concentrating photovoltaic) technology is a promising concept because it can work with the fixed installation. However, besides the economic consideration, the environmental impacts of the CPV module throughout its life cycle should be addressed as compared with the flat PV technology. Thus, in this paper, a novel high optical performance low-concentration concentrator namely asymmetric compound parabolic concentrator (aCPC) for building south wall integration is proposed. And based on the proposed aCPC-PV module, a life cycle assessment (LCA) has been performed for the low-concentration PV in China to make a scientific comparison with the PV module with the same output level environmentally. Several environmental indicators are calculated for Beijing, Hefei, Lhasa, Lanzhou, Harbin. The primary energy demand, energy payback time and environmental impacts are considered over the entire life cycle of the aCPC-PV module. The results show that the primary energy demand, energy payback time and environmental impacts of the aCPC-PV module are all relatively lower than that of the PV module with the same output. It is confirmed by the LCA study that the aCPC-PV module on behalf of the low-concentration PV technology is still a feasible and effective way for actual engineering because it’s more economic and more environmental friendly than the PV technology although the PV is experiencing continuous decrease in price and increase in efficiency. [ABSTRACT FROM AUTHOR]

Solar photovoltaic (PV) modules can not only generate electricity but also act as external shading devices of buildings. Solar PV shadings can effectively reduce the solar heat gain through windows, but might have a negative impact on the indoor daylight performance. Therefore, it is worth investigating the optimum design of solar PV shadings since the thermal, daylighting and power generation performance are closely integrated. In this paper, a numerical simulation model was utilized on the basis of EnergyPlus to investigate the energy saving potential of solar PV shadings with various tilt angles and orientations in Hong Kong. The results indicate that the optimum installation position for solar PV shadings is south facade with 30° tilt angle in order to maximize the electricity generation. However, considering the electricity savings from air-conditioning system and the increased electricity consumption for artificial lighting, it is recommended that solar PV shadings should be installed on a south facade with 20° tilt angle. Furthermore, the annual overall electricity benefits of solar PV shadings were compared with the widely used interior blinds. The results show that the well-designed solar PV shadings can achieve much more annual overall electricity benefits than interior blinds. [ABSTRACT FROM AUTHOR]

China's iron and steel sector has met many obstacles, such as high energy consumption and huge CO2 emissions. In order to deal with these problems, the Chinese government has launched a series of corresponding policies. With the assistance of Long-Range Energy Alternatives Planning System (LEAP) software, this paper established the LEAP policy model to explore performances of industry policies formulated by the government. The model consists of a baseline scenario and three policy scenarios based on different policies. Three policy scenarios in the LEAP policy model are based on policies of phasing out backward production capacity, promotion energy saving technologies, and establishment of a carbon emissions trading market. Results indicate that there is great potential for the CO2 emissions mitigation in the iron and steel sector. The effects of four scenarios are ranked as follows: emissions trade scenario (ET) > cut excessive capacity scenario (CEC) > technology improvement scenario (TI) > business-as-usual scenario (BAU). From the point of view of the iron and steel industry, this research tries to cast light on the future performances of industrial policies, and the results reveal that CO2 emissions would be abated significantly if those policies were successfully implemented. [ABSTRACT FROM AUTHOR]

A key strategy for lowering emissions and reducing the effects of climate change is to execute energy-saving retrofits in residential buildings. Despite extensive research on different retrofit pathways for building energy efficiency, the current retrofitting of the aged housing stock in China is still constrained by several factors, including occupant willingness, government financial situation, and low energy prices, so retrofitting projects are almost entirely government-led and most of the solutions of existing studies are not applicable. Therefore, a comprehensive optimization framework for low-budget compliance retrofit strategies in the Chinese context is urgently needed. In order to fill this gap, this study established a set of procedures for developing an optimal energy-saving retrofit scheme in old residential buildings in Nanjing city. The results showed that the optimal scheme can reduce 18.52% of residential building energy consumption in five central districts of Nanjing City, and the total energy saving is about 260.43 GW h. The study also showed that improving wall insulation and heating, ventilation, and air conditioning systems were the most efficient retrofit measures but came at a high cost. Setting a reasonable air conditioning target temperature was further identified as the most cost-effective retrofit measure. This study provided a mechanism for district-level retrofit planners to formulate a strategy that may take the performance of retrofitting on the environment and the economy into account while still adhering to code requirements. [ABSTRACT FROM AUTHOR]

Zero-energy buildings have attracted interest worldwide as they consume less energy and can alleviate energy shortages caused by rapid economic development. This paper presents a review of the research and development regarding zero-energy buildings in China. First, it briefly introduces the evolution of the definition of zero-energy buildings and discusses the key influencing factors of such buildings in China. Then, envelope design, selection of mechanical and electrical equipment, and solar energy utilization aspects of zero-energy buildings are examined. Additionally, this paper discusses the development and application of zero-energy buildings in China, including project types, design methods, energy resources allocation, and energy operation management. Finally, this paper analyzes China's policies for zero-energy buildings, including incentive mechanisms, laws and regulations, and problems encountered, and provides suggestions for promoting zero-energy buildings in China. We expect this review to identify gaps and future directions for research and development, which will lead to new technologies, methods, policies, and standards that can be applied to zero-energy buildings. • Research and development of zero energy building in China is comprehensively reviewed. • Influencing factors and relevant zero-energy building design components are examined. • Development and application of zero-energy buildings in China are examined. • Zero energy policies in China are analyzed and suggestions for the promotion of zero-energy buildings are provided. [ABSTRACT FROM AUTHOR]

A novel wallboard with double layers shape-stabilized phase change materials (SSPCMs) for year round energy management was proposed. Its energy saving potential in five typical climate regions of China was studied. One office room integrated with double layers SSPCMs wallboard was used for simulation platform. The other normal office room with the same envelope and just without double layers SSPCMs wallboard was used as reference room. Studies were conducted to investigate the energy saving potential of double layers SSPCMs wallboard in five cities representing five typical climate regions of China, including severe cold region, cold region, hot summer and cold winter region, hot summer and warm winter region, mild region. The optimal melting temperature and corresponding thickness of SSPCMs wallboard in five representative cities were given when the energy saving potential reached maximal value. It concluded that the optimal melting temperature of internal SSPCM layer was effected by indoor air temperature and the optimal melting temperature of external SSPCM layer was effected by outdoor air temperature. The characteristic of optimal values in the five representative cities were given for reference in this paper. [ABSTRACT FROM AUTHOR]

Maximizing energy efficiency within HHFs (hospitals and healthcare facilities) is a major challenge in the field of energy conservation. This paper studies the key barriers to the implementation of energy-efficient technologies in China's public HHFs. For this purpose, a preliminary survey was conducted at the Beijing Municipal Health Bureau in order to assess the energy conservation efforts being made at 20 public HHFs. In the survey, a list of specific barriers to energy efficiency was created and HHF staffs were asked to rank these barriers in the order of importance. The results show that the economic incentives, appropriate technology, as well as enforceable laws and regulations are insufficiently supported by the government, have become the most significant obstacles to the improvement of energy efficiency. To remedy this, policymakers should take a multipronged approach which addresses the hospitals, projects, and technical and operating procedures in order to encourage the full participation and support of all stakeholders involved. Specifically, the government should offer multilevel economic incentives and reward policies; establish practical mandatory targets for building energy efficiency; provide demonstrable best practices in terms of the project, techniques, and operating procedures; and promote awareness of the importance of property risk management. [ABSTRACT FROM AUTHOR]

Building sector accounts for a large percentage of the total national energy consumption in most of the countries, thus it is critical to formulate and implement appropriate energy saving policies in the building sector. This paper focuses on energy saving policies in the building sector by conducting a comparative study between Japan and China. The exiting Building Energy Saving (BES) policies, actual effectiveness of policy implementation and obstacles to the effective policy implementation are compared in sequence. Related policies are categorized into four groups: control and regulatory instruments; economic/market-based instruments; fiscal instruments and information and voluntary actions. Policy effect analysis identifies that BES policies have promoted building energy saving in both Japan and China. Obstacles comparison reveals that Japan and China shared many obstacles including high transaction costs and lack of applicable methodology. Compared with Japan, China is suffering more obstacles such as inefficient enforcement, insufficient levels of information and awareness and immature financial regulation system. Based on the previous findings, common suggestions for overcoming these obstacles of BES policies in Japan and China are presented, such as the accurate methods of baseline identification and emission accountings, innovative incentives, and more capacity building activities. Distinct suggestions for Japan and China are also added by considering their own situations so that both countries can further improve their BES policies. [ABSTRACT FROM AUTHOR]