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• 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]

• POE was carried out to compare the design target and operational effect after use. • A Large Irregular Green Commercial Building was chosen for in-depth analysis. • We recommend the building energy saving and carbon emission reduction strategy. Commercial buildings, especially large irregular commercial buildings with complex space and dense occupation, have high energy consumption and carbon emissions. Moreover, the actual operating performance differs significantly from its design, in terms of energy conservation and carbon emissions. This study selected an irregular large-scale green commercial building in Dalian, a coastal city in the cold zone of China. The running energy consumption and indoor physical environment were investigated and analyzed, and a satisfaction survey was conducted using the Post-occupancy evaluation (POE) methods. The promotion strategies of holistic design were proposed by comparing the operational building performance with the design target. The research shows that the energy consumption of the building was 68.02 kWh/m2, which failed to meet the standard requirements. The carbon emission was 74.76 kgCO 2 /m2. Less than 10 % of humidity in summer fell in the expected range, and the lowest value of PM 2.5 concentration in winter was 28.3 %. The score of indoor environmental quality and service satisfaction was low. This paper identifies the problems and analyzes the differences between the operation stage and design phase. It provides recommendations and guidelines for optimizing the carbon emission and indoor environment based on the performance improvement of building operational conditions. [ABSTRACT FROM AUTHOR]

• This method integrates uncertainty analysis and cluster analysis methods. • Proposed novel zoning indicators are statistically significant. • Moves from traditional weather-based approaches to a performance-based approach. • Robust tool to tackle complex relation between climate and building energy efficiency. • Provide evidence for the rationality of decision making in energy policy. Climatic zoning is an important tool in building energy policy and regulations, smaller and more homogeneous climate zones could help enhance the rationality of energy policymaking. In most countries, climate zoning is based on simplified climate models, and it is difficult to accurately represent the energy demand characteristics of buildings. Therefore, this paper proposes a novel climate subdivision method that tackles the complex relations between climate and building energy-efficient, which move from traditional weather-based approaches to a performance-based approach. Integrate the uncertainty analysis method and the building dynamic performance simulation to extract a novel statistically significant index as the basis for classification. The K -means clustering method and discriminant analysis method are used to obtain and verify the clustering results, respectively. Furthermore, the comparison with clustering results based on degree days confirms the superiority of the new method proposed in this paper in identifying building energy demand. The method is applied to the cold climate zone of China as a showcase. The results show significant differences in building energy demand and the order of key features affecting building performance between each region in the climatic zones. The zone can be further sub-divided into four groups considering the climate factor and building feature uncertainty, and clustering results have been verified by several evaluation indicators. [ABSTRACT FROM AUTHOR]

Monitoring buildings' heat loss and quickly discovering high energy-consuming buildings in a certain area is of great significance for urban management departments to propose urban governance and management measures from the perspective of global optimization. Developing a 3D-infrared (3D-IR) model of a building or a complex created with infrared thermograph (IRT) obtained by unmanned aerial vehicle (UAV) technologies would greatly contribute to a comprehensive observation on the thermal performance of a study objective. In this paper, a procedure for high energy-consuming building screen based on the 3D infrared (IR) models of multiple buildings is proposed and demonstrated as an effective approach for regional evaluation comparing with measured heating energy data provided by the local municipal department. Firstly, the 3D-IR model of multiple buildings is established, where the single building models are built based on UAV-IRT technology respectively, and the modelling condition as well as the temperature-color mapping relationship of each building is unified. Secondly, the measuring schemes and the evaluation method of the building thermal performance based on the 3D-IR model is proposed. Thirdly, the energy-consuming performance of five buildings in Jining, a city in northern China, is measured and analyzed by using the above-mentioned methods. Finally, the proposed evaluation method of the building performance is applied to evaluate the tested buildings. By referencing to measured heat energy data, the proposed method can be taken as an efficient and reasonably accurate screen method. [ABSTRACT FROM AUTHOR]

Abstract: A liquid desiccant based independent humidity control (IHC) air-conditioning system driven by heat pumps is presented in this paper. The system consists of a liquid desiccant fresh air processor and a high-temperature chilled water system. The operating principles of the fresh air processor and the whole system are presented in detail. Based on the in situ system installed in an ecological building of Shanghai Research Institute of Building Sciences (SRIBS), a performance investigation was performed in summer, 2007. The measurement results show that (1) the indoor temperature and humidity both are in the specified range; (2) the supply water temperature of the high-temperature refrigerator is higher than the corresponding indoor air dew point temperature, so no condensed water would be formed on the fan-coil unit (FCU) surface; and (3) the average coefficients of performances (COPs) of the fresh air processor and the high-temperature refrigerator are 6.24 and 4.38, respectively, and the average COP of the whole IHC system is 5.28. [ABSTRACT FROM AUTHOR]

Abstract: The shading-type building-integrated photovoltaic (BIPV) claddings can act as power generators as well as external shading devices of a building, which reduce the energy consumption of the building. However, there is little information about energy impacts of different tilt angles of the shading-type BIPV claddings. By considering the typical meteorological conditions of Hong Kong, the energy performance of the shading-type BIPV claddings, in terms of the electricity generation and the cooling load reduction, is analyzed in this paper. The optimum tilt angle of PV modules for maximum electricity generation is found to be 20° instead of local latitude. Combining electricity generation and cooling load reduction, it can be concluded that the optimum tilt angles for the first type of the shading-type BIPV claddings vary from 30° to 50°, while the optimum tilt angle for the second type is 0°. [Copyright &y& Elsevier]

• Traditional Chinese kang systems are reviewed and compared. • Improved kang systems are summarized and compared. • Possible directions for further study of Chinese kang are suggested. Chinese kang, which serves as the main space heating equipment in rural residences of cold regions of China, has received increasing attention due to people's increasing requirements of thermal comfort and concerns about indoor air environment in recent years. Most of the existing studies focused on one specific type of Chinese kang by using experimental or numerical methods to investigate the system's energy performance and its effect on the indoor environment. Therefore, there is a lack of comprehensive review of all the existing types of Chinese kangs. This paper firstly classifies the traditional Chinese kangs into three categories according to their culture and ethnic background. Secondly, the detailed construction, flue modality and thermal performance of the three kang systems are reviewed and compared. Thirdly, some recently proposed improved kang systems are introduced and analyzed. Finally, based on the review results, several possible research opportunities are suggested to guide future research on Chinese kangs. [ABSTRACT FROM AUTHOR]

• Thermochromic coatings with five different colors were prepared. • Spectral reflectivity and color-changing properties of the samples were measured. • A three-step control method is used to simulate energy performance for an office building model. • Thermochromic coatings are most favorable in areas with uniformly distributed cooling and heating demands. Thermochromic coatings are promising in lowering air conditioning energy consumption of buildings. In this paper, thermochromic coatings with five different colors are prepared and their optical properties are measured. A two-story office building model is established and simulation is conducted to evaluate the energy performance of thermochromic coatings by using a three-step control method based on their dynamic color-changing properties. A comparative analysis is carried out for thermochromic coatings, cool coating and common coating. It is observed that when the building is located in Shanghai, average daily surface temperature of thermochromic coatings is lower than the common coating during cooling period and higher than the cool coating during heating period. Annual energy consumption results indicate that thermochromic coatings can avoid the penalty of increasing heating load for cool coatings. In particular, the annual energy consumption of the office building using thermochromic coatings can be reduced by 4.28–5.02 kWh/m2 compared to the common coating, and 0.73–1.47 kWh/ m2 compared to the cool coating. Simulation of other cities in different climate zones in China reveals that thermochromic coatings have better energy saving effects especially for the areas with hot summers and cold winters, and relatively uniform distribution of cooling and heating demands. [ABSTRACT FROM AUTHOR]

In the context of residential energy consumption, the top-down approach and bottom-up approach have been developed to model and predict residential energy demand, and the bottom-up engineering model is a promising choice and an effective tool for urban planners and policymakers. However, unlike the existing building stock databases in some developed countries or regions, China's Pearl River Delta (PRD) region lacks such building databases. Thus, the study established a database of 120 residential districts in the PRD region, and developed typical models through the data of the collection, quantification and classification. In this paper, three typical residential district models have been defined, which was a supplement to previously develop seven typical residential building models. Moreover, four common family patterns in the PRD region were determined by literature research, the corresponding schedules and basic settings were developed subsequently for them. Finally, the simulations of the energy consumption of the three residential districts were conducted, whose energy consumption intensities were 28.43 kWh/m2a, 28.41 kWh/m2a and 28.24 kWh/m2a, respectively. The results of the simulation are similar to the results of the actual energy audit, which is considered that the typical residential buildings are representative yet simple-to-use energy model. [ABSTRACT FROM AUTHOR]

• PMV overestimated the thermal sensation of students. • Students preferred cooler thermal environment. • A higher percentage of students felt local thermal discomfort. • The lower limit for 80% acceptability determined by TAV could be 19 ℃. • If indoor design temperature is 19 ℃, 3.46% of annual heating load can be saved. A classroom thermal environment directly not only influences students' thermal comfort but also energy-saving. Numerous studies indicate that students' actual thermal comfort is different from the PMV and adaptive model predictions, and the current thermal comfort standards could not be applicable for the classroom thermal environment design and evaluation. This paper aims to study the university students' general and local thermal comfort by a field survey conducted in a classroom during the heating season in Taiyuan, China. The results indicated that PMV overestimated the thermal sensation of students. Thermal acceptance vote (TAV) defined the widest acceptable temperature range, and the lower limit for 80% acceptability could be 19 ℃ in Taiyuan. Students preferred a cooler than a neutral environment. The indoor design temperature determined by the heating load duration curve (LDC) was about 21.85 ℃. If the indoor design temperature could decrease from 21.85 ℃ to 19 ℃, 3.46% of the annual heating load could be saved. Moreover, although a majority of students found the environment general thermal acceptable, a higher percentage of students felt local thermal discomfort. Local thermal comfort should be a critical issue for the classrooms' thermal environment improvement. [ABSTRACT FROM AUTHOR]