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[Display omitted] • A wireless-energy green city concept integrating WPT, renewable energy, and infrastructure is proposed. • Security-electrification, digitization, and intelligence are bolstered by the incorporation of WPT into urban settings. • The SDGs are advanced by the wireless-energy green city's energy, environment, and social economy benefits. The significance of energy stability in urban development has increased as the use of intelligent devices continues to expand and extreme weather poses a threat to the integrity of electric networks. Wireless power transfer technology is well-known for its dependability, security, and adaptability, and has reached billions of market share in China alone in the cell phone and electric vehicle sectors over the past decade, with the electric vehicle wireless charging market expected to grow at a compound annual growth rate of over 30% by 2023. Combining WPT with renewable energy, electric vehicles, and recharge infrastructure is a promising new application for smart city development. This paper examines the history, characteristics, and six classifications of WPT technology through the lens of urban development, in addition to its successful implementations in seven contexts, such as portable devices and transportation, based on a survey of 161,425 papers. We propose a dependable and efficient research-to-application life cycle for high-power WPT operations, which is capable of achieving efficiencies of approximately 90 percent at approximately 50 percent of the original cost. In addition, the significance of incorporating WPT technology, renewable energy sources, and urban infrastructure into the design of sustainable cities is highlighted. This study determined that WPT is advantageous for promoting the construction of space and ground photovoltaic plants, as well as photovoltaic rooftops, and also serves to accelerate the promotion of electric vehicles, smart devices, and charging roads. The findings of this study cast light on three problem areas and six future prospects of WPT, as well as its multifaceted benefits in terms of energy, the environment, and the social economy of sustainable cities. [ABSTRACT FROM AUTHOR]

[Display omitted] • Incentive initiatives on energy-efficient renovation of existing buildings in China were analyzed. • The dynamic evolution of incentive initiatives was analyzed from different perspectives. • A critical analysis of representative initiatives in two batches of pilot cities was conducted. • Implementation barriers and limitations on energy-efficient renovation of existing buildings were summarized. • Recommendations and pathways of promoting related incentive initiatives were proposed. Under China's national strategy of carbon neutrality by 2060, it is urgently necessary and challenging for the governments to proactively explore policy tools to facilitate energy-efficient renovation of existing buildings. Currently, a considerable number of studies have been conducted on building energy-efficient renovation and its derivative topics, however, a comprehensive overview on incentive initiatives related to existing renovation practices in China is still scarce, such as a lack of critical correlation analysis between national and local initiatives, a lack of the synthesis and critique towards the latest policies and related achievements, and inadequate generalization of the diverse and multi-layered barriers and challenges in building energy-efficient renovation practices. To address these issues, this paper adopts a diversified policy segmentation approach to deeply analyze the dynamic evolution of the incentive initiatives from both national and local level perspectives, as well as to establish the related network of policy linkages between national to local, and between different localities. In addition, this paper presents a critical analysis on representative initiatives in two batches of pilot cities, and proposes good practices and valuable experiences for building energy-efficient renovation. Finally, this paper further summarizes and discusses the barriers to building energy-efficient renovation from four perspectives: governments, householders, enterprises and research institutions, and proposes a series of targeted and feasible pathways and strategies. This study can provide theoretical guidance and targeted recommendations for the formulation of policies, standards and regulations for building energy-efficient renovation in China. [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]

The objective of this paper is to optimize the passive design of newly-built residential buildings in hot summer and cold winter region of China for improving indoor thermal comfort while reducing building energy demand. In this respect, this paper investigates the performance of a representative apartment building in the city of Shanghai and evaluates the optimum solutions by using a developed optimization approach, which includes three major steps of 1) setting the model for multi-objective optimization, 2) sensitivity analysis for reducing the dimension of input variables, and 3) multi-objective optimization by using the Non-dominated Sorting Genetic Algorithm II (NSGA-II) coupled with the Artificial Neural Network (ANN), among which a novel indicator for evaluating the annual indoor thermal comfort of residential buildings of Shanghai named Comfort Time Ratio (CTR) is defined based on the modification of Szokolay’s theory in terms of bioclimatic analysis, and the impacts of passive design variables on the indoor thermal comfort and building energy demand in terms of different directions are comprehensively investigated. Results of the multi-objective optimization indicate that the residential buildings of Shanghai have a great potential in comfort-improvement and energy-saving. A series of novel optimal passive design tactics for residential buildings in Shanghai are derived accordingly which could be easily understood and conveniently carried out by the architects in practice. [ABSTRACT FROM AUTHOR]

As most promoted solution of climate change, green buildings become more popular and widely promoted in China recently. This paper compared the carbon emissions of green buildings with non-green buildings; therefore, a life cycle carbon emission assessment approach (LCA) was attempted. In the present paper, we have integrated existing database Building Environmental Load Evaluation System (BELES) developed by Tsinghua University and twenty-six real existing buildings (nine residential and seventeen commercial buildings). Buildings located in two major climate zones were selected, namely, zone II and III. Five phases were defined for a whole life cycle of building: Phase 1 Raw Materials, Phase 2 Transportation, Phase 3 Construction, Phase 4 Operation & Maintenance and Phase 5 Demolishment. In each phase, the emissions were calculated separately. It is found that whole life cycle CO 2 (LCCO 2 ) of green buildings are lower than that of non-green buildings, i.e., 10% for residential and 32% for commercial buildings, respectively. For both residential and commercial buildings, Operational & Maintenance phase contributes the majority of emissions in the whole life cycle, about 69.2–89.3%. Moreover, green buildings have slightly higher embodied CO 2 emissions than non-green buildings, but with much lower operational emissions, and this phenomenon is significant in residential buildings. This indicates that the LCCO 2 of green buildings start to match with LCCO 2 of non-green buildings after operating for certain years, which is the turning point. Furthermore, China implemented Standard for Energy Consumption of Buildings in December 2016, which listed two values for energy efficiency in operational phase, which represents requested and optional. It can be expected that the emissions in Operational & Maintenance phase of green buildings will be further reduced in the future. Consequently, in the future, the dynamic flow of turning point of residential buildings will be shifted downwards from existing 14 years found in this paper. [ABSTRACT FROM AUTHOR]

Recently there has been growing interest in regenerative evaporative coolers (REC), which can reduce the temperature of the supply air to below the wet-bulb of intake air and approach its dew-point. In this paper, we designed, fabricated and experimentally tested a counter-flow REC in laboratory. The REC’s core heat and mass exchanger was fabricated using stacked sheets composed of high wicking evaporation (wickability of available materials was measured) and waterproof aluminium materials. The developed REC system has a much higher cooling performance compared to conventional indirect evaporative cooler. However, the decision to use the REC for China buildings depends on a dedicated evaluation of the net energy saved against the capital expended. Such an evaluation requires the hourly-based data on the availability of cooling capacity provided by the REC for various climates. The paper used an experiment-based method to estimate the cooling capacity and energy savings provided by the proposed REC for China’s various climates. By using the experimental results and regional hourly-based weather data, the energy saving potential of the REC against an equivalent-sized mechanical air conditioner alone was analysed. The results indicate that, for all selected regions, the REC could reduce 53–100% of cooling load and 13–58% of electrical energy consumption annually. [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]

The acceleration of urbanization and the growth of population are considered to be the reasons of increasing demands for construction, life quality and energy consumption. This leads to more research in climate adaptive strategies such as traditional design methods, construction techniques and building materials. Traditional dwelling has been successful in achieving harmony between dwelling and climatic environment, which is one of the most important conditions for sustainability. Firstly, this paper focused on analyzing the characteristics of traditional dwellings in Qinba mountainous areas to adapt to the climatic environment. Secondly, two typical dwellings constructed respectively with brick and earth materials were selected for monitoring and simulating of its indoor thermal, luminous and ventilation environment in summer and winter. In addition, the research summarized the advantages and disadvantages of the dwelling's physical environment in response to climatic characteristics. It revealed that the traditional earth dwelling is well adapted to the local climate during summer, although the indoor thermal comfort is not fully satisfactory during winter. Finally, we prompted effective climate adaptive strategies of traditional earth dwelling, such as natural ventilation, thermal insulation and thermal buffer space. We want to provide guidance and reference for the development of traditional dwellings in the mountainous areas. [ABSTRACT FROM AUTHOR]

• The effects of green roofs and practical green façades within courtyard area on public buildings investigated for "Hot Summer, cold Winter" region of China. • Internal surface temperatures for areas with and without external greening monitored and compared. • Heating and cooling energy consumption before and after greening compared from computer simulation as well as from smart meter readings. • Actual heating and cooling energy consumption before and after greening compared using statistical analyses. T -statistics and p -values show significant reductions were achieved. The "Hot Summer Cold Winter" climate region of China is one of the most challenging regions for providing occupant comfort in buildings, with high demands for heating as well as cooling, together with high humidity levels. Although the performance of buildings has improved with the implementation of the new Chinese National Building Standards for the Zhejiang Province, it is believed that adding passive strategies could help to alleviate the problem even further. This paper aims to investigate the effects of adding horizontal greening (green roof) and vertical greening in the courtyard area to existing public buildings in the "Hot Summer Cold Winter" climate region of China. Using computer simulation and measurements from a monitored case in the city of Ningbo, the effects of green retrofitting on human comfort and energy consumption are analysed. Simulation results suggest that with partial horizontal and vertical greening, the cooling load could be reduced by 8.8% and heating load by 1.85%. Comparisons between actual energy use before and after greening on the case building showed significant reductions in both winter and summer, confirming the positive effects of vertical and horizontal greening of public buildings in this region. [ABSTRACT FROM AUTHOR]

• A new spray cooling system is proposed based on PV/T and heat recovery in sow houses. • A simulation model is developed to dimension the new system. • The maximum error is less than 7.2% for the key equipment models in the new system. • The optimal operating ranges of new system are determined in five climate regions. • The operating control suggestions of new system are obtained in five climate regions. In this paper, a new spray cooling system (NSCS) is proposed based on PV/T and heat recovery in sow houses. It contributes to improving system applicability in high-humidity areas and reducing system energy consumption due to solar dehumidification and heat recovery. Meanwhile, the simulation model of NSCS is established and the reliability is verified for the models of its key equipment. The results show that the maximum error is less than 7.2% for the models. The optimal control parameter ranges are further determined for NSCS in five climate regions in China through simulation. The results show that in hot-summer and warm-winter (HSWW) region or hot-summer and cold-winter (HSCW) region, the optimal operating ranges are 40–45 kW and 7245–9245 kg/h for spray power and mass flow rate of circulating water, respectively. However, they are 25–30 kW and 13245–15245 kg/h in other three climate regions, respectively. Finally, the annual performance parameters are compared for NSCS in five typical cities. The regional applicability and operating control suggestions are further obtained for NSCS in five climate regions. The results show that the heat recovery coefficient and energy efficiency ratio are the maximum when NSCS is operated in HSWW and HSCW regions. In high-temperature and arid regions, removing desiccant wheel from NSCS may be a good method to reduce system investment and energy consumption. Meanwhile, the surplus electric and thermal energy can be used for regional energy utilization in NSCS. The above conclusions can determine the regional applicability of NSCS and guide its operating control in different climate regions. [ABSTRACT FROM AUTHOR]

[Display omitted] • Carbon emissions are explored in China's building operations from provincial perspective. • GDIM is employed to factorize ten affecting factors of CO 2 emissions in building sub-sectors. • CO 2 emissions of building sub-sectors are predicted with dynamic simulation. • The contribution of provinces to the change and peak of national emissions are discussed. Carbon emissions from building operations have a critical impact on achieving carbon peaking goal in China. However, the provincial emission performance in building operations are quite different and it is still unidentified how they affect the national emission change and peaking target, making national emission reduction target hard to implement at the provincial level. This paper explores the driving factors leading to emission changes and examines the prospective emission peaks in China and China's provinces by adopting generalized Divisia index method (GDIM) and the combination of scenario analysis and Monte Carlo simulation. Furthermore, the regional emission heterogeneity and the contribution of provinces to the change and peak of national emissions are discussed to identify regions and provinces that should be focused on emission monitoring. Results show that in China and most Chinese provinces, energy consumption of commercial buildings, energy consumption and floor space of urban residential buildings besides income improvement, and the per capita CO 2 emissions of rural residential buildings contributed greatly to emission growth. Under current policies, commercial and urban residential buildings in most provinces would fail to reach their emission peaks ahead of schedule. The urban residential buildings in the northern region, commercial and rural residential buildings in the eastern region caused higher CO 2 emissions. At the provincial level, Shandong, Shanxi and Hebei made the top contribution to total emissions of commercial, urban residential and rural residential buildings, respectively. Shandong and the provinces in north China of urban residential buildings and four provinces including Shandong, Guangdong, Hebei and Zhejiang of commercial and rural residential buildings had the significant impact on the uncertainty of the peaking time of CO 2 emissions. These findings provide a strong decision-making reference for Chinese government to formulate targeted regional emission reduction policies in building operations. [ABSTRACT FROM AUTHOR]

With the rapid development of China's power industry and the improvement of residents' living standards, the electricity consumption of residents has increased significantly. With smart electrical household appliances are walking into resident's household, residents can change their appliance's usage behavior by using the built-in software to save electricity without sacrificing the electricity usage comfort a lot. This paper studied the influence of residents' smart electrical appliance usage behaviors. We establish a comprehensive theoretical framework model based on TPB and VBN theory, in addition, we considered external information influence, including resident's usage knowledge, policies, and so on. We design a questionnaire and employ structural equation model (SEM) model to analyze the influences, and we find that the attitude, social norm, and external information have a significant direct influence on residents' smart electricity usage behavior, altruism awareness, and personal norm have no direct significant influence on residents' smart electricity usage behavior, however, they work through the external information and then have an indirect influence on residents' smart electricity usage behavior. As a result, we put forward some specific policy suggestions to promote residents' behaviors for the government, smart electric household appliance manufacturers, and the power service department. [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]

• Ventilation rate and arrangement are crucial to prevent airborne disease in healthcare facilities. • Local ventilation is practical for supply fresh air and diluting contaminants in high-risk areas. • Microplastics emerged as potential virus carriers in indoor environments, warrant further investigations. The prevalence and transmission of airborne infections pose significant challenges to public health, leading to consequential negative impacts. Ventilation strategies are crucial in mitigating airborne infections in healthcare settings, preventing the spread of infectious diseases, thus protecting patients and healthcare workers. While individual studies have explored various aspects of ventilation in healthcare settings, a synthesized overview of the current state of knowledge is lacking. Therefore, this study attempts to bridge the gap by conducting a review and bibliometric analysis based on 198 papers published within the recent decades (1993–2022). The findings will provide a holistic understanding on the innovative interventions and identify areas for future research, thereby contributing to the development of effective guidelines for controlling airborne infections. The co-authorship analysis revealed that China emerged as the main contributor in the current research field due to the keen interest of researchers and the substantial financial support provided by funding agencies. The keyword co-occurrence analysis identified three primary research hotspots within the field, (i) the optimized ventilation strategies for combating airborne infection, (ii) the transition towards the application of computational fluid dynamics (CFD) in analyzing airflow patterns, and, (iii) the characteristics of airborne particles and their impact on infection transmission. The present review highlights the significance of local ventilation as an additional measure to the main ventilation system for enhanced dilution of contaminants in high-risk areas. The transition towards dynamic airflow analysis considered human movement's effect, allowing for more precise assessments and tailored ventilation strategies optimization. The review also underscores the emerging concern of microplastic as an indoor contaminant with potential implications as a virus carrier, emphasizing further research on its behavior and impact on airborne infection transmission. [ABSTRACT FROM AUTHOR]

In recent years, water-side free cooling has been broadly applied in data centers to lessen the high cost of energy consumption. The energy-saving opportunities of free cooling have been recognized by numerous studies across the world. In this paper, the field test and energy performance evaluation were performed in an operational data center with water-side free cooling, located in Chongqing, China. Existing problems were found during tests, including the insufficient cooling capacity of towers in wintertime and the inability to activate partial-free cooling. The results of the tests show that the reduction in Power Usage Effectiveness (PUE) is much lower than the expected. To understand the marked discrepancies, the performance of the cooling tower was discussed in terms of the approach temperature and actual cooling capacity. The maximum cooling capacity in winter is only about 50 % of the rated. With the consideration of the cooling tower configuration performance in different climate conditions, the conservative energy effects were calculated in 34 provincial cities of China. To prolong the hours available, optimized operation schemes of cooling towers are presented. The available hours for free cooling could be increased from 730 h to 1300 h when operating at 67 % of rated flow rate, resulting in a decrease in the energy saving of chillers between 8.44 % and 21.05 %. [ABSTRACT FROM AUTHOR]

Glued Laminated Bamboo (GluBam) has been innovated under the support of modern industrial technology, and this renewable material can drive the development of building structural system in a fashion of low carbon footprint. From the perspective of carbon emission, energy consumption and cost-based economy, this paper presents a comprehensive life cycle assessment (LCA) of steel-GluBam hybrid truss and virtually designed steel truss for a comparison. A steel-GluBam hybrid truss constructed at the Nanjing Tech University is used to carry on this study. The system boundary (i.e., production phase, transportation phase, construction phase, operation phase and disposal phase) of life cycle are fist determined. The mechanical properties of the truss structure are considered as the functional equivalence. The inventory of construction materials and the elements in each phase in the life cycle is compiled from the SimaPro and the available literature/specification. Based on the inventory analysis, the Monte Carlo method is employed to conduct the uncertainty analysis of carbon emission of the truss. The assessment results show that the life cycle carbon emission, energy consumption and cost of the steel-GluBam hybrid truss are equal to 4572.5 kgCO 2eq , 71.15 GJ and 15626.6 CNY, respectively. The production phase is the largest contributor to the carbon emission, energy consumption and cost, and the following one is the operation phase. Whereas the transportation phase, the construction phase and the disposal phase together contribute to only the small parts of emissions and cost. GluBam has the function of carbon sequestration leading to the reduction of carbon emission and energy consumption in the production phase, and other phases have no advantage on the emissions and cost of GluBam. The 95% confidence interval of life cycle carbon emission based on the Monte Carlo simulation is estimated as [4290,6370] kgCO 2eq for the steel-GluBam hybrid truss. With respect to the whole life cycle, using GluBam to replace the steel pipe in the upper chord pole and the diagonal web pole of the truss has a little larger cost but its environmental impact and energy consumption reduce a lot. The railway transportation of GluBam reduces 36.5 kgCO 2eq carbon emission, 0.68 GJ energy consumption and 83.7 CNY cost in the life cycle with reference to the road transportation. The steel-GluBam hybrid truss optimized based on the functional unit occurs in the case of reducing the cross-section of steel pipe from 42 mm × 4 mm to 32 mm × 2.5 mm. [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]

[Display omitted] • This paper summaries the present regulations and policies concerning M−TES (Mobilized thermal energy storage) in China. • The policies are analyzed based on the aspects including facility manufacture and operation, road transportation, and financial guidance. • The results can provide references for the government or policy makers to promote the development and safe operation of M−TES in China. Mobilized thermal energy storage (M−TES) is a promising technology to transport heat without the limitation of pipelines, therefore suitable for collecting distributed renewable or recovered resources. In particular, the M−TES can be flexibly used for the emergency heating in the COVID-19 era. Though the M−TES has been commercializing in China, there is not any specific regulation or standard for M−TES systems. Therefore, this paper summarizes and discusses the existing regulations and policies concerning M−TES in the aspects of facility manufacture and operation, road transportation, and financial support and guidance. Furthermore, the suggestions were presented including necessary consensus on the development of M−TES among different departments, consideration of local conditions when drafting or revising regulations and policies, sufficient investment, or subsidy on the R&D of M−TES, and qualification recognition of M−TES companies and staffs. [ABSTRACT FROM AUTHOR]

Energy efficiency standards for household appliances have been adopted in many countries to mitigate negative externalities, reduce emissions, and save energy. Using Chinese provincial-level panel data from 2008 to 2018, this paper builds a difference-in-difference model to examine the mechanism by which energy-efficiency upgrades in China's air conditioners affect urban household electricity usage. The results show that the upgrades have brought about an obvious reverse effect, with urban household electricity usage increasing rather than decreasing. Reducing the unit costs of energy service has enhanced residents' sensitivity to cooling demand. Driven by the substitution and income effects, urban residents may increase the intensity and frequency of their AC use. Additionally, this reverse effect is heterogeneously dependent on the family size and urban residents' age structure rather than their educational level. When families are larger and have more children, the reverse effect is more pronounced. This paper's findings provide useful recommendations for policy-makers to formulate policies that are synergistic with energy efficiency standards for household appliances. [ABSTRACT FROM AUTHOR]

[Display omitted] • A numerical model is proposed for seasonal thermal energy storage (STES) couple with solar collector. • The model is featured as relatively high computational speed and accuracy. • An analysis on technical planning and operational design for the STES is offered. • The key parameters for system design and control are investigated with instructive results. Seasonal thermal energy storage (STES) systems are a key component in expanding the share of renewables in energy programs because they provide schedulability and flexibility. However, such a large-scale system requires careful planning to avoid high investment costs. Therefore, numerical models are becoming increasingly important as an alternative. This paper develops a numerical model of STES coupled with solar collector. The model was verified based on the experimental data of the Huangdicheng Project in China. The results show that the relative error in the charging mode and discharging mode is only 1.57 % and 0.46 %, respectively. Then, the effects of different charging and discharging mode on the heat storage efficiency of the tank and the efficiency of solar collector systems in STES were studied. The study found that in the initial charging stage, the water temperature rise curve caused by different flow rates is very different. In the design of the collector-storage area ratio, the relatively economical collector-storage ratio of this model is around 3768 L/m2. The selection of different proportions of discharging energy in the discharge stage has a great impact on the heat storage efficiency of the system in the next year. Moreover, the influence of different depth-diameter ratios of the tank on the system heat storage efficiency is discussed in detail, which has important guiding significance for model application and system analysis. This paper provides some references for the scale design and operation optimization of cylindrical STES. [ABSTRACT FROM AUTHOR]

Abstract Heating energy conservation is an important part of China's energy conservation strategy. China's coal-fired heating is reducing and heating energy conservation policy is enhancing but not in a significant manner. This paper aims to figure out the actual realization of Chinese governments' ex ante expectations towards energy conservation policy in the heating industry. A trans-log production function is established incorporating asymmetric energy price decomposition and seemingly unrelated regression method is adopted to estimate the own-price and cross-price elasticity of factor input demands of the heating industry, then the direct energy rebound effect is estimated within China's heating industry. The results indicate that the actual energy-saving effect of the heating industry in China only realizes 60.04% of the theoretical energy-saving goal. Energy rebound in the heating industry in China is not only influenced by technical progress but also influenced by its state-owned monopoly status. [ABSTRACT FROM AUTHOR]

Abstract In the last two decades, a remarkable socio-economic transition has been witnessed in China. Existing studies have only shown that energy consumption of residents is influenced by economic growth and urbanization. It is unclear, however, how socio-economic transition influences the inequality of energy consumption among urban and rural residents. Focusing on the empirical investigation of two different regions (the eastern developed provinces with little energy resources and the western underdeveloped provinces with rich energy resources), this paper examined the major socioeconomic determinants of energy consumption inequality between urban and rural residents. The results of panel data analyses showed that there was a long-term relationship between socio-economic transition and changes in the inequality of energy consumption among residents. Meanwhile, the results revealed that the influence of socio-economic transition varied from regions to regions. Generally, the influence of urbanization on the inequality of both quantity and diversity was found to be the most profound and significant in all regions. The industrialization transition also exerted far-reaching effects, although its influence was determined by the growth of industry sectors. Moreover, the influence of economic transition was only significant in underdeveloped regions and such an influence fitted to a Kuznet's curve. For the transition of technology and education, its influence was significant in the developed provinces but was only effective in affecting the diversity of inequality. In summary, the findings of this research present policymakers a better understanding of the relationship between the socio-economic transition and inequality in energy consumption. [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]

Highlights • A multi-level building energy consumption benchmarking index system for cooling in large commercial buildings is presented. • The recommended index value is calculated based on real operation data of a commercial building in China. • Evaluation efficiency is improved by using a simplified calculation method. • The benchmarking method was validated using real data from eight large shopping centers in China. Abstract Urban development rapidly increases the total area and the energy consumption of large commercial buildings. Accordingly, the total energy consumption is the focus of numerous energy saving studies. An optimal benchmarking system provides a recommended energy consumption level for each building as well as identifying and prioritizing challenges to energy saving in each building. Based on detailed sub-metering system data and building operational data, this paper presents a simplified energy consumption benchmarking method for air-conditioning systems that cool large commercial buildings. Firstly, a multi-level benchmarking index system is established. Next, the energy performance data of eight large shopping centers in China validates the simplified benchmarking method and finally, the energy performance data of the participating shopping centers is analyzed under the present method. Our data focus on the energy saving potential, as well as informing improvement strategies for building energy performance, that can be used for efficient energy benchmarking process for cooling in large-scale commercial buildings. [ABSTRACT FROM AUTHOR]

In order to investigate the relationship between outdoor air pollution and sick building syndrome (SBS) symptoms, the CCHH (China, Children, Home, Health) group in Shanghai conducted a cross-sectional survey on the current incidence of SBS symptoms among residents in five districts of Shanghai during April 2011–April 2012. It also collected the related outdoor air pollutants data from Shanghai environmental monitoring center (SEMC), including nitrogen dioxide (NO 2 ), sulfur dioxide (SO 2 ) and particles with aerodynamic diameter less than 10 µm (PM 10 ). The logistic regression models were used in this paper to study the associations between air pollutants and SBS symptoms. Results were found that the daily mean concentrations of NO 2 and SO 2 met standard requirement, but that of PM 10 exceeded the limit values of the standard in China during this survey. The significant differences were found between the pollutants concentration in urban and suburban area. In addition, the incidences of three categories of SBS symptoms among residents were 79.1% for general symptoms (GS), 65.2% for mucous membrane symptoms (MS) and 35.7% for skin symptoms (SS), respectively. Multiple logistic regression analysis by two case studies illustrated that three outdoor air pollutants, both their concentration quartiles and equal increment, were all associated to and taken as the risk factors for SBS symptoms, for GS OR NO2  = 1.62 (1.18–2.22), MS OR NO2  = 1.58 (1.21–2.06) and SS OR PM10  = 1.21 (1.09–1.35). Furthermore, the new pollutants expressed as the mixtures of their combination were also significantly associated with part of the SBS symptoms. The synthetic air quality indexes of all surveyed residents were calculated as III-level, which represented mild pollution. Therefore, it would be an effective way to decrease the incidence of SBS symptoms in residence to reduce the outdoor air pollution and control the penetration from outdoor to indoor environment. [ABSTRACT FROM AUTHOR]

In this paper, an intelligent ensemble machine learning (EML) method - Bagging was developed for thermal perception prediction. Field data was collected in naturally ventilated (NV) and split air-conditioning (SAC) dormitory buildings in hot summer and cold winter (HSCW) area of China during the summer of 2016. The indoor physical measurement and subjective survey were conducted simultaneously during the field study. To determine the merit of the proposed Bagging approach, the performances of Bagging approach were compared against the artificial neural network (ANN) and support vector machine (SVM) regarding conventional statistical indicators, i.e., mean absolute error (MAE), root mean square error (RMSE), coefficient of determination (R 2 ) and Pearson correlation coefficient (r). Several thermal indices, i.e., thermal sensation (TS), effective temperature (ET*), standard effective temperature (SET*) and predicted mean vote (PMV), were adopted to access the occupants’ thermal comfort and evaluate the model prediction. In our case study, the Bagging model's R 2 for TS, PMV, ET* and SET* were 0.4986, 0.9892, 0.9920 and 0.9900, respectively. It shows higher accuracy than SVM and ANN models in thermal perception prediction and outperforms the classical PMV index in TS prediction. Results indicate the proposed Bagging model's prediction performance is reliable and is highly accurate to predict the thermal perception. [ABSTRACT FROM AUTHOR]

This paper investigates the climate change impact on cooling energy consumption of office buildings in four major architectural climate zones in China. The results show that there are apparent differences in the responses of monthly or yearly cooling loads to climatic change in different climates. Dominant factors affecting monthly cooling loads change from dry bulb temperature (DBT) to wet bulb temperature (WBT) with the climate zones changing from severe cold to hot. The yearly cooling load was mainly afftectd by DBT in severe cold climate, whereas the WBT had the dominant effect in the other climates. With the continuous warming climate, the yearly cooling load did not rise significantly for any climate zone except for severe cold climate zone where cooling load had a significant increase ( p  < 0.01). More importantly, the cooling load showed a weak decrease in Guangzhou. These results suggest that different measurements for buildings cooling energy conservation should be made in different climate zones. The humidity effect should be fully considered to improve buildings energy efficiency, especially in the hot climate zones. The continuous increase of temperature in the future does not necessarily increase cooling loads of buildings in the cold, hot summer & cold winter and hot summer & warm winter climate zones, and change trendency of humidity in the future need to be considered to predict cooling energy consumption. [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]

• Analyzed residents' thermal demand characteristics under the global climate change. • A new thermal comfort evaluation model of traditional dwellings was established. • The new thermal neutral temperature and comfort range of residents were proposed. • Different measures to improve the old and new types of dwellings were put forward. Global climate change has led to increased differences in the indoor thermal environment of traditional dwellings and residents' thermal adaptability, but quantitative research in this area needs to be updated and improved. In this paper, taking the old and new types of traditional dwellings of Guangfu Ancient City in Hebei province, China as the example, we first investigated the current situation of indoor thermal environment and thermal comfort characteristics of residents by means of subjective questionnaire survey and objective data measurement. The measured data showed that the average indoor temperature of old-type traditional dwellings in winter was far lower than the thermal comfort range of human body, and it was also higher than the relevant standard in summer. Secondly, we established a new thermal comfort evaluation model of traditional dwellings and proposed a new thermal neutral temperature of residents: old-type traditional dwellings (18.1 °C in winter and 27.1 °C in summer), new-type traditional dwellings (19.8 °C in winter and 25.7 °C in summer). Although the measured data showed that the thermal environment quality of the old-type traditional dwellings was poor, the residents had strong thermal adaptability. Finally, we put forward the different living performance improvement strategies of old and new types of traditional dwellings: The old-type traditional dwellings should focus on strengthening the thermal performance of the envelope structure, while the new-type traditional dwellings should solve the problem of low indoor humidity in winter. This research improves the evaluation system of human thermal comfort of dwellings in cold region of China, and provides a good case reference. [ABSTRACT FROM AUTHOR]

In China, the population is expected to continue to grow together with construction of new buildings. Consequently, the energy demand required by the building sector will inevitably rise. This paper focuses on the Chinese residential sector and describes the structure by using the EfB—energy for buildings model. Using this tool it is possible to simulate the trend of the energy demand until 2030. A range of different scenarios – at national and regional level – is presented and discussed, including government plans and the application of some proposed recommendations. The analysis suggests that the energy consumption in this sector will not stop its growth and in 2030 it will comprise between 9500 and 14,000 PJ. Meaningful energy savings can be achieved with the introduction of more aggressive policies and behavioural change. Many difficulties have been faced in this work because of the complexity and rapid evolution of the Country; anyway, it can be considered as a starting point for future research. Among further improvements, the paper suggests the introduction of a more complete description of the building types, the association of the floor area evolution to the construction sector activity and the inclusion of economic and environmental evaluations. [ABSTRACT FROM AUTHOR]

Electricity consumption of the Chinese building materials industry accounted for 8.4% of industrial and 6.2% of national electricity usage in 2011. The purpose of this paper is to estimate the future electricity intensity and conservation potential of the Chinese building materials industry. This paper adopts a cointegration method to establish a long-run equilibrium relationship between electricity intensity and factors including technology, power tariff, enterprise scale and value-added per worker. Electricity conservation potential in the Chinese building materials industry is predicted to be 90.5 billion kW h in 2020 under the moderate scenario, which is more than the total electricity consumption of Malaysia in 2007; and 150.9 billion kW h under the advanced scenario, which is more than the total electricity consumption of Saudi Arabia in 2005. Conserved electricity in building materials industry would account for 1.2% and 2.0% of national electricity consumption under the two scenarios, respectively. More importantly, we find that the electricity intensity gap between Chinese and the world's leading building materials industries could be significantly narrowed by 2020 if aggressive energy conservation policies were implemented. Finally, based on the results of our study, future policy priorities and directions are suggested. [ABSTRACT FROM AUTHOR]

Residential energy consumption level, structure, and potentiality are crucial indices reflecting economic and social development. In rural China, energy poverty is still prevalent, and economic poverty is a critical factor that deteriorates energy poverty. This paper combines income- and asset-based measures of wealth to provide a more dynamic perspective on the effects of economic poverty on energy poverty. Results show that for the household which in an average asset or income level, when its assets and income increase by 10%, the probability of a household choosing clean fuels increases by 0.007 and 0.002, respectively. Rural household prefers gas than electricity when household income and assets increase. To solve the energy poverty problem in rural areas, governments need to take measures to improve the accumulation of wealth, raise the infrastructure level and increase the employment rate. [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]

While urban form affects building energy consumption, the pathways, direction and magnitude of the effect are disputed in the literature. This paper uses a unique dataset to examine the effect of urban form on residential electricity consumption in Ningbo, China. Using survey and utility bill data of 534 households in 46 neighborhoods in the city, we model the electricity use of households using a multi-level regression model. We find that neighborhood street configuration and tree shade are important in controlling residential electricity consumption and, consequently, greenhouse gas emissions. Our results suggest that seasonality and dwelling type condition the effect of neighborhood densities on electricity consumption. Neighborhood density is associated with household electricity consumption in summer months, while there is no such association in winter months. As neighborhood density increases, households in slab and tower apartments in dense urban neighborhoods consume more electricity in summer months, which can be partly explained by exacerbated heat island effect. Interestingly, the neighborhood density is negatively associated with summer electricity consumption for single-family houses, suggesting that the effect of neighborhood density is different for different types of dwelling units. [ABSTRACT FROM AUTHOR]

Fully air-conditioned atria have become increasingly popular in architecture design due to their appealing aesthetic and iconic features to general public. In certain regions of China, climate diversities in winter (freezing-cold) and summer (warm-humid) are huge. Energy consumptions due to air-conditioning of atria in these regions are enormously high. Thus, their corresponding energy managements without compromising the indoor thermal comfort are extremely challenging. The geometric configuration of the atrium has preliminary and significant impacts on the indoor environment and further influences the energy consumption. The impacts of atria’s geometric configuration on indoor thermal condition and energy consumption under highly diversified climate conditions in China are studied in this paper. A fully air-conditioned enclosed atrium with square plane and cross-section is considered in this research. Atria with different section aspect ratio (SAR) and skylight sizes are investigated with a combination of (1) field measurements and computational fluid dynamics (CFD) simulations for temperature distribution and (2) energy simulations for the corresponding energy performance. Case studies for the temperature distribution profile for atria with different SAR and the quantitative correlations between atria’s SAR and its energy performance are presented. Optimum skylight size based on the objective function to minimize the annual energy consumption will also be reported. [ABSTRACT FROM AUTHOR]

• The data requirements of quota methods are summarized, and a city-scale database containing 670 credible government office buildings is established. • By comparing the processes, the results and applicability, the selection basis of quota methods under different conditions is refined. • A flow chart of the formulation process and method selection of city-level building energy consumption quotas is constructed. • It is proposed that special attention should be paid to the outliers, and the characteristics of outliers in Chongqing are summarized. Energy consumption quota policies are effective management measures to promote energy conservation and emission reduction in China. Cities need to choose an appropriate method to formulate local energy consumption quota standards. This paper is based on the data of 670 government office buildings in Chongqing and the selected quantile method (QM), quota-level method (QLM) and multiple linear regression (MLR) method, which are widely used in the formulation of city-level energy quotas. By comparing their interpretability, evaluation, consistency and stability, the application conditions and applicability of each method are summarized. MLR has the strongest explanatory power but the highest requirements for the technology and information dimensions. The QLM is more explanatory and stable than the QM and is more suitable for the initial stage of energy quota management. When using the QLM, we should consider scientific classifications and reasonable quota levels. Special attention should be given to "outliers" with abnormal evaluations of the quota results. The outliers in Chongqing are characterized as buildings that have been used for more than 10 years and have an area of less than 5000 m2. Finally, this paper constructed a flow chart of the formulation process and method selection to help policymakers better understand how to choose the most appropriate method and identify inefficient buildings. [ABSTRACT FROM AUTHOR]

Emission reduction in buildings is essential to combat climate change. However, current strategies failed to balance development and emissions reduction goals. This paper selects a public building in China and simulates its initial energy consumption and carbon emissions. Then it establishes a multi-objective optimization model to explore cost-effective and emission-reduction strategies, considering photovoltaic and ground-source-heat-pump (GSHP) systems. Finally, NSGA-Ⅱ is used to solve, and sensitivity analysis is carried out. Results show that: (1) Energy consumed by the air conditioning system is the largest in January for heating and in July for cooling, validating the accuracy of the energy simulation model. (2) Economic efficiency and emission reduction effect are better when photovoltaic and GSHP systems are implemented simultaneously. (3) Electricity price, initial investment cost, annual solar peak hours, and the proportion of shallow geothermal energy significantly impact carbon emissions and cost. (4) The photovoltaic and power grid substitution ratio will exceed 8% every five years, and all substitutions will be completed in 2050. After adopting the GSHP system, the complete replacement will be advanced to 2045. Setting subsidies significantly shortens the payback period of investment and ensures firms' economic benefits. In summary, using photovoltaic and shallow geothermal energy is conducive to reducing emissions and saving costs in the long term. [ABSTRACT FROM AUTHOR]

• A micro-holes radiant plate without adding dynamic and piping system was designed. • Micro-holes radiant plate combines orifice plate air supply and radiant heat transfer. • The deviation between indoor and set temperature was within 1 ℃ for all types. • The maximum ratio of the radiant heat transfer quantity was close to 70 %. In order to alleviate energy shortage and maintain comfortable indoor environment, radiant air conditioning system is widely used. This paper designs and produces a miniaturized micro-holes radiant plate, which has the characteristics of orifice plate air supply and radiant heat transfer. The micro-holes radiant plate can be installation on the ceiling or sidewall without adding dynamics system and piping system. In order to explore the heating performance of the micro-holes radiant plate under different installation types, an experimental bench of air source heat pump micro-holes radiant plate heating system was built in Harbin, China, for laboratory heating. The experimental results showed that the indoor average temperature under various installation types could basically meet the set requirements, and the deviation was within 1 °C. The indoor horizontal temperature distribution was relatively uniform, and the temperature difference of each measuring point was less than 2 °C. The indoor vertical temperature difference was the smallest under the installation type with sidewall 50 mm from the ground at only 2.68 °C in the sitting position and 3.14 °C in the standing position, which meet China and ASHRAE standards. The ratio of the radiant heat transfer quantity under the sidewall heating was about 60 %, while the ratio under the ceiling heating was only about 30 %. The maximum ratio of the radiant heat transfer quantity was close to 70 % under the installation type with sidewall 50 mm from the ground. The experimental results provide theoretical support for the design and operation of air conditioning systems in severe cold regions. [ABSTRACT FROM AUTHOR]

• A new urban building energy modeling tool-AutoBPS was developed. • AutoBPS calculated urban building energy demands, analyzed energy retrofit and rooftop PV potential via EnergyPlus. • AutoBPS automatically generated multi-zone models, considering shading from surrounding buildings. • A downtown district of 3633 buildings in Changsha, China, was simulated to demonstrate the tool's features. • All three energy conservation measures and PV installation could save 38.6% of total energy demand. China has promised to peak carbon emissions by 2030 and become carbon neutral before 2060. Achieving this target requires actions from all sectors, especially the building sector, which accounts for 33 % of the total energy consumption in China. Within this scenario, this paper introduces a new urban building energy modeling tool, Automated Building Performance Simulation (AutoBPS), to calculate urban building energy demands and to analyze energy retrofit and rooftop photovoltaic (PV) potential. AutoBPS uses a building-by-building approach to automatically generate multi-zone (one zone per floor) models based on the city building dataset, considering the shading effect by surrounding buildings. The tool simulates building energy use and PV generation via EnergyPlus. A downtown district of 3633 buildings in Changsha, China, was selected as a case study to demonstrate the features of the tool. Firstly, annual baseline energy uses of 1793 GWh were simulated by inputting Geographic Information System (GIS) data. Then, different energy conservation measures (covering envelope, lighting, cooling system upgrade, etc.) and roof PV generation systems were adopted to explore energy saving potential. The results showed that the window upgrade was the most energy-efficient individual measure for residential buildings, while the lighting upgrade was that one for commercial buildings. Altogether three measures could save 2.7 ∼ 30.7 % of annual site energy use intensity per building. The total energy demand could be reduced by 18.5 % by combining all measures and saved by 38.6 % when PV installation was added. AutoBPS can be easily applied to other cities, supporting urban energy efficiency plans for carbon reduction goal implementation. [ABSTRACT FROM AUTHOR]

Abstract: Reducing the energy consumption of air-conditioning systems is becoming increasingly important. This paper focuses on the air-conditioning system in Terminal 3 in Xi’an Xianyang International Airport, the first airport terminal to adopt radiant cooling in China. In the large spaces of this airport terminal, a temperature and humidity independent control (THIC) system has been adopted instead of a conventional nozzle air supply method, which significantly reduces the energy consumption of the air supply. The radiant floor is the main mechanism for indoor temperature control, while a liquid desiccant outdoor air processor combined with displacement ventilation is responsible for humidity control. Ice storage is adopted to reduce operating costs, and the supplied chilled water temperature can be as low as 3°C. This paper examines the performance of the THIC system in detail. The indoor environment is determined through measurements to be comfortable, and the on-site performances of key components in both the airport terminal and the cooling plant are investigated. The outdoor air processor supplies air of appropriate temperature and humidity ratio; two kinds of radiant floors are used for temperature control, both with measured cooling capacities of about 30–40W/m2; and the energy efficiency ratio (EER) of the cooling plant is 2.62. [Copyright &y& Elsevier]

Abstract: It is not feasible to apply the traditional prediction method to predict hourly building cooling load at the urban energy planning stage because of the limited building information and complexity of energy prediction. This paper presents a simplified prediction model: Hourly Cooling Load Factor Method (HCLFM) that can provide quick and fair estimate of building cooling load for large-scale urban energy planning. The paper introduces the assumptions and principles of the proposed method, as well as discussing the implication and limitation of the approach. As a verification and demonstration, the method is applied to an office building in Beijing. The predicted results show that the dynamical trend of the cooling load is reasonable. The study further analyzes the potential causes of prediction errors and the significance of various cooling load influence factors. [Copyright &y& Elsevier]

Abstract: With the development of urbanization in China, more and more high-rise residential buildings are constructed, mostly with 10–15 stories. Solar water heating system has been widely used in low-rise residential buildings in China, while its application in high-rise apartment is still in the initial stage. In this paper, the current application situation of solar water heating system in urban residential buildings of China is investigated. Additionally, demonstration projects of high-rise residential building are introduced, in which the application feasibility and limitation of solar water heating system are emphasized and some appropriate planning types of that are discussed. Finally, this paper analyzes the applicability of solar water heating systems integrated design in typical high-rise apartments from various aspects (such as architectural elevation, architectural plane and detailed construction) in the planning and designing phase. [Copyright &y& Elsevier]

Seasonal variation of thermal comfort demands directly affects the energy needs for heating or cooling purpose. In previous studies, the differences of neutral temperatures between summer and winter were revealed, but the studies on the difference of human thermal adaption in transitional seasons are insufficient. To clarify this, this paper presents a year-long survey which was carried out in 505 residential buildings in six cities located in the Hot Summer and Cold Winter (HSCW) zone of China involving 11,524 subjects. Results show a significant difference of adaptive responses in different seasons, and a lag of behavioral responses behind climate change in transitional seasons is observed. Occupants not only adjust clothing insulation according to air temperature in different seasons, but also actively control indoor air movement, including closing/opening windows and using fans. The seasonal, monthly and daily neutral temperatures are studied, implying that occupants’ thermal experience has significant effect on their thermal comfort by behavioral, physiological and psychological paths. According to the comparative study, the running mean air temperature method and aPMV model are recommended in free-running space. The findings provide scientific evidence to the concept that dynamic thermal comfort temperature range should be considered in evaluation of indoor thermal environment. [ABSTRACT FROM AUTHOR]

This paper presents a micro energy grid to a community and estimates the effect of the urban micro energy grid on the reduction of energy demand and carbon emissions. Micro energy grid enables to share various energy sources generated at local plants and renewable sources for multiple buildings with different energy profiles. A community in China was selected for the implementation of the micro energy grid. A number of key performance indicators(KPIs) were developed to act as a framework for the overall community micro energy grid design. Site-wide strategies were selected to meet the KPIs and minimize the capital cost of the project. Financial analysis on the community micro energy grid model was performed and different scenarios were set up in order to find the optimalconditions for the government incentive, the investment discount rate, system capacity and development (demand) size of the project. It was found that a community in China adopting micro energy grid can achieve 26% carbon emissions reduction and 25% energy consumption savings compared to the conventional building energy systems and its payback period is 51 years with 10% discount rate and a government incentive of $0.052 per kWh. [ABSTRACT FROM AUTHOR]

To ensure sufficient daylight in rooms, daylight performance metrics are the basic references to guide building design or to benchmark a building against another in terms of daylighting in a room. Daylight factor (DF) is the most commonly accepted daylight performance metric, but it has limitations in evaluating the daylighting of a room space in a real daylight climate, as defined under CIE standard overcast sky, while daylight autonomy (DA) is a climate-based performance metric which takes into consideration the regional daylight climate. Based on long-term continuous measurements of daylight illuminance in a test room under real climate, combined with scale model tests under an artificial sky and computational simulations, the quantitative relationship between monthly average daylight illuminance, DF and DA are holistically analyzed in this paper. The result shows that a monthly average daylight illuminance above 300 lx in a room located in Canton requires a DF of no less than 1.8% for north-facing space. Finally, the depth of DA 300lx [50%] daylit area for four cardinal directions was proposed in comparison with DF. [ABSTRACT FROM AUTHOR]

In the tourism industry, hotels and homestay facilities account for considerable amounts of energy consumption and CO 2 emissions. Unlike other types of buildings, occupancy has significant fluctuations over time, while mostly being ignored or using a simple assumption based on energy use intensity or setting the occupancy levels. Due to the lack of occupancy rate information, great uncertainties exist in hotel operations, which leads to erroneous estimates of energy consumption in existing hotel buildings. This paper examines hotel operation practices in China with real occupancy rate data which is critical for reducing the uncertainty of estimating energy consumption patterns. Specifically, this study proposes a two-stage comprehensive and quantitative performance assessment approach for the homestay hotel building considering the system's energy and economic performance simultaneously. Regarding energy performance, there are two key facets to consider: renewable energy penetration and grid impact performance. Additionally, the economic performance (annual income and extra annual investment) of various energy portfolios is evaluated using break-even analysis. The impacts of large fluctuation in occupancy rate on electrical loads are considered and assessed in typical homestay hotels. The proposed assessment approach can comprehensively quantify the impacts of the photovoltaics (PV) areas and battery capacities on the system performance in terms of energy and economics. According to the results of the occupancy-based assessment, the ideal PV area and battery capacity are 400 m2 and 16 kWh, respectively, as opposed to the optimal energy portfolios (PV area 600 m2 and battery capacity 24 kWh) determined from conventional assessment results. [ABSTRACT FROM AUTHOR]

• Nine human physiological markers and thermal sensation questionnaire in stable indoor thermal environment is collected. • The deviation analysis between thermal sensation vote and PMV standard is conducted. • Detailed correlation analysis of nine physiological information with thermal sensation is performed. • A data-driven thermal sensation predictive model based on multiple physiological information is designed. This paper investigates the correlation of human thermal sensation with multiple physiological information in stable indoor thermal environment. Fifteen young male subjects from East China participate in the experimental study. The thermal sensation votes (TSVs) are collected by subjective questionnaire, and six physiological information are measured simultaneously, i.e., wrist skin temperature, blood pressure, heart rate, heart rate variability (ECG), skin conductance and blood oxygen saturation. A total of nine different physiological markers including four ECG signals are recorded. The deviation analysis between TSV and PMV standard is conducted. A detailed correlation analysis of nine physiological markers with thermal sensation is performed. It is found that young males of East China prefer lower ambient temperature in summer than PMV's prediction. Two environmental and seven physiological variables have obvious correlations with TSV. Among them, wrist skin temperature, heart rate and ECG (pNN50) are three physiological markers that have high correlations with TSV. On this basis, a data-driven thermal sensation predictive model based on multiple physiological information is designed. The accuracy is better than that of skin temperature based predictive model or PMV evaluation. [ABSTRACT FROM AUTHOR]

With increasing concern for building energy efficiency, domestic hot water (DHW) supply systems, which have significant energy-saving potential, have drawn more attention from both practitioners and academia. In this study, we conducted a field study on seven centralized hot water supply systems in Beijing, measuring the water temperature and flow rate in primary or secondary pipes and collecting the operating records of hot water usage, gas consumption, and electricity consumption. In addition, we discuss the main problems existing in the current centralized DHW system. Based on measured data, this paper further analyzes energy losses from each link in the hot water supply system. A mathematical model is then proposed for simulating the energy consumption of hot water supply systems under various conditions such as various boiler efficiency, thermal insulation thickness, water pipe network structure, and hot water usage. The model is also used to explore the main factors that lead to low performance of centralized DHW systems in China. Finally, we analyze the applicability of diverse heat sources (e.g., electricity, gas, and heat pumps) in centralized DHW systems in China. [ABSTRACT FROM AUTHOR]

In China, more than 100 million people live in earth-based dwellings currently. However, there have been few studies on measures for improving indoor thermal environment and decreasing energy consumption of adobe buildings systematically. So, this paper studied the measures mentioned above. Firstly, parameters such as indoor thermal environment, PMV, thermal properties and thermodynamic disfigurement of building envelope were measured and analyzed on a quadrangle adobe dwelling in Gansu, China. Then, three optimization schemes (transforming layout only, transforming external walls only and changing the two simultaneously) were put forward. Finally, the thermal environment and energy consumption of the optimization schemes were analyzed by numerical simulation, and the cost benefit analysis of them was carried out. Among those schemes, scheme of changing layout and external walls simultaneously leads to the best performance in both the two respects mentioned above, while scheme of transforming layout only gives the worst performance. But, when both taking consideration of economy and energy saving, the preferred plan is scheme of changing layout only, and the worst is scheme of transforming layout and external walls simultaneously. This study has been conducted to give guidance when constructing or reconstructing quadrangle adobe dwelling, which is distinctive and historical in China. [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]