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• A novel application mode of CSP with HEHP technology is proposed. • The flexible operation benefits of CSP with HEHP technology in the IES are analysed and quantified. • The carbon emission trajectory of the IES containing CSP with an HEHP device is depicted. • CSP with HEHP technology increases the utilization of solar energy. • A rational combination of the hydrogen and thermal energy storage capacities are necessary. The efficient integration of renewable energy with hydrogen storage is an important means for China to achieve carbon neutrality. Concentrated solar power (CSP) is an emerging technology for solar energy utilization that combines the advantages of power generation and energy storage. However, CSP has not been fully exploited because of the high generation cost and an incomplete market mechanism in China. The heat collected by CSP can be utilized for high-temperature electrolytic hydrogen production (HEHP), which is an efficient technology for hydrogen production and storage, and reducing carbon emission. Thus, a low-carbon operating mode for an integrated energy system (IES) consisting of wind, solar and hydrogen energy is proposed in this paper. First, an optimal operation model of electricity-heat-hydrogen coupling for an IES containing CSP and HEHP is established. Second, the effect of CSP with HEHP on the total operation performance of the system is evaluated from the aspects of the system economy, renewable energy utilization, and carbon emission. Finally, the model is validated by a case study of an island IES, and an optimal sizing for hydrogen energy storage and thermal energy storage of CSP is determined. The results show that CSP with HEHP can effectively improve the utilization rate of solar energy and reduce the carbon emissions of the system, offering an approach for carbon reduction planning and the operation of CSP in electric-hydrogen energy systems. [ABSTRACT FROM AUTHOR]

• The solar potential in different residential blocks is simulated. • The influences of block morphological parameters on solar potential are varified. • Four parameters that impact on the block solar potential more than 70% are verified. • The facade PV capacity in high-rise and hybrid residential blocks is more than 66%. • The average PV installation rate of roof, south and west facade is 96%, 32% and 39%. Block-scale application of photovoltaic technology in city is becoming a viable solution for renewable energy utilization. Rapid urbanization process has made urban buildings have huge development potential for solar energy in China, especially in residential areas that occupy large parts of the city. However, the residential blocks in China show differences in the morphological layout and parameters, which means they have diverse potential for solar energy development. This paper studies the effect of quantified morphological parameters on solar potential for residential blocks in Wuhan, China. The distribution characteristics of solar potential in different block environments are discussed. Various strategies are evaluated in terms of the installation position and height of PV modules. The results showed that floor area ratio, building density, average building height and building interval have significant impact on solar potential for residential block, and their correlation can reach 75%, 71%, 78% and 72% respectively. The average PV installation ratio of roof, south facade and west facade can reach 96%, 32% and 39% respectively. The results of this paper not only provide a reference to the block-scale application of PV technology in urban environment, but also stimulate the implementation of photovoltaic policies on various residential blocks in China. [ABSTRACT FROM AUTHOR]

• Bibliometrics overview of ZEB publications. • Draw of the collaboration networks from ZEB research publications. • Brought out thematic trend of the development ZEB over the time. • Discussions of the main challenges and solutions for ZEB studies. Zero Energy Building (ZEB) is gaining more attention as a solution to significantly mitigate the environment concerns. However, a bibliometric analysis of the topic, a very useful method to analyze the database of published publications and reviews, is lacking. Especially, to provide when and how this concept has been brought out, insights into the state-of-art technology, the findings of the collaboration networks and the challenges of ZEB. To address this gap, in this paper, ZEB studies have been reviewed using multiple perspectives and analytical tools, such as VOSviewer and Biblioshiny to analyze the collaboration networks and the thematic trends of ZEB publications. The original data was retrieved in Scopus, a total of 1051 documents including research articles and reviews published from 1976 to 2020. The analysis of the number of publications over the years shows that the development of Zero energy building research has gone through three stages: a slow development period from 1076 to 1999, followed by a development from 2000 to 2010 and finally a rapid development from 2011 to 2020. The study also reveals different rankings, including the most widely collaborated scholars, the most cited scholars, the most published countries, etc. Therein, the United State, United Kingdom and China have the most research on ZEB. Based on the analysis of co-occurrence network and evolution of thematic keywords, it is found that energy efficiency and life cycle assessment (LCA) are the main challenges for the achievement of ZEB target. Finally, these challenges have been discussed and solutions provided. [ABSTRACT FROM AUTHOR]

• Experiences from SWH systems mandatory installation in China were summarized. • The interaction of seven stakeholders in SWH building application was analyzed. • Three key factors for the successful mandatory installation of SWH were summarized. • Recommendations were given for using the mandatory installation policy effectively. • The government should regularly evaluate the effectiveness of policy implementation. The paper summarizes the implementation experiences and lessons learned from the solar water heating (SWH) system mandatory installation policy in China. In-depth interviews, questionnaire surveys and field investigation were conducted to understand the prevailing attitudes of the stakeholders associated with the application of SWH in buildings. Scenario analysis was used to analyze the effect of expanding the coverage of mandatory installation policies. The results show that due to the strong market externalities of SWH building applications, the government must provide inducements to stakeholders through mandatory policies or fiscal incentives to create an impetus for them to use SWH extensively. For China, it is necessary to strengthen and support the utilization of renewable energy policies and extend the mandatory installation policy of SWH systems to taller buildings to fulfill the national renewable energy application goals. The most reasonable technical route, full process control, and attention to system operation and maintenance are the three key factors for the successful implementation of a mandatory installation policy for SWH systems. The policy recommendations presented in this paper can not only be applied to China but also other developing countries as well. [ABSTRACT FROM AUTHOR]

• Optimal Window-to-Wall Ratios were recommended for various building orientation. • Integrated models with different glazing area and orientation combinations were proposed. • Daylight factor, air temperature and air velocity were computed for each test scenario. • Three optimal intervals of Window-to-Wall Ratio were determined respectively. • Intersection interval of the three subsets is the optimal interval of Window-to-Wall Ratio. Since the ratio of glazing and opaque areas on building facade has significant impact on the indoor visual and thermal comforts as well as energy consumption, the optimal Window-to-Wall Ratio is necessary to be explored for the rural residences with a large quantity in China. Due to the traditional dwellings has been representative of housing samples among rural residences, Sizhai traditional dwellings situated in Zhejiang Province were chosen as the study buildings in this paper. The building model is rotated to 20° increments clockwise to create 18 building orientation intervals. Furthermore, the Window-to-Wall Ratio of front facade for the building model was divided into 8 intervals at increments of 0.1, from [0.1–0.2] to [0.8–0.9]. Through indoor environment simulation, the daylight factor, air temperature and air velocity were computed for the test scenarios with different building orientation and Window-to-Wall Ratio combinations. Three optimal intervals of Window-to-Wall Ratios at a series of building orientations corresponding to the daylight factor, mean maximum indoor temperature and mean indoor air velocity are determined respectively, based on the criteria of national codes and thermal comfort ranges. The intersection interval of the three subsets is the optimal interval of Window-to-Wall Ratio for the study building. In addition, for verifying the accuracy of research results, two validation techniques (i.e., comparison of experimental measurement data, and comparison of computational results from other simulation tools) were adopted in this paper. [ABSTRACT FROM AUTHOR]

• The use of GB techniques based on 106 projects was examined for future upgrading. • Water-saving and site planning categories exhibited the highest achievement. • This study identifies four main barriers limiting GB quality upgrading. • This study presents recommendations in four aspects for GB quality upgrading. • Upgrading GB projects for urban heat mitigation and urban flooding management. Building sector is one of the primary culprits of environmental deterioration and energy consumption. Green building (GB) can be an effective solution to these challenges and has been prioritised by many nations, while the quality of most GBs was still low. Therefore, this paper aims to examine the application of GB techniques. In specific, an empirical study was conducted among 106 GBs in China. Results indicate that both water-saving and site planning categories received the highest achievements, followed by indoor environmental quality and energy-saving, and the material-saving and innovation categories were the most difficult to achieve. The items in site planning, energy-saving and indoor environmental quality clusters that depended more on design techniques could be realised evenly, while the water-saving and material-saving clusters that relied more on materials and equipment witnessed two extremes: one approaching to 100% and one close to zero. There could be an increase in technique achievement from low-quality GBs to high-quality GBs. Nevertheless, the achievements of many items were extremely in both one-star, and two- and three-star groups. Some even witnessed the reduction from the low-quality GBs to the high-quality GBs. A further investigation indicated that the unavailability of GB technique checklist, the impact of economic cost, low technological operability and the unavailability of GB products constrained the GB technique application. The combining impacts of them could further lower the GB technique application. To unlock these barriers, efforts should be made from the perspective of (1) revision and localisation of GB standard, (2) extensive technical support, (3) government regulations and support, and (4) the co-benefits: integration with other programmes. Overall, this paper is of value to improve GB technique application and facilitate the transitions towards higher quality GB agenda. [ABSTRACT FROM AUTHOR]

• The method of combining DesignBuilder and jEplus + EA is proposed. • The best configuration form of windows and shading system is investigated. • Four-objective optimization about energy consumption and thermal comfort is solved. • A typical high-rise office building with large area glass is used as case study. • The research is conducted in four typical climatic regions of China. As a large energy-consuming part of the envelope, windows and shading system play a significant role in building savings. Once established in the primary design stage, it is difficult to make changes later, especially for high-rise buildings with large areas of glass. Moreover, strongly influenced by solar radiation, the configuration of windows and shading system conflicts with each other in terms of energy consumption and indoor comfort, the optimal configuration of windows and shading system under different climatic regions has not been well solved at yet. This paper proposes an easy-operation, useful, and efficient multi-objective optimization method, using a smart optimization algorithm NSGA-II in combination with DesignBuilder energy simulation software, especially beneficial for non-programming designers. In this research, a typical high-rise office building with a large area window has been selected as a case study. Building orientation, the configuration of windows and shading system, including materials for each layer of the double-layer window, installation angle and depth of overhangs have been taken into consideration, aiming to minimize the heating, cooling, lighting energy consumption and discomfort hours, and to find the mutual relationship between each other. A set of Pareto solutions can be obtained after optimization, and the most recommended variable parameters of windows and shading system in four cities representing severe cold climate, cold climate, hot summer and cold winter climate, and hot summer and warm winter climate can be identified, respectively. Besides, Pareto optimal solutions can give designers different scheme choices based on preferences, which are of great significance to provide guidance and suggestion for designers in the early design of buildings. [ABSTRACT FROM AUTHOR]

Abstract: The paper investigates a single-sided naturally ventilated buildings potential model considering number of factors in China. This model can be used to estimate potential of natural ventilation via local climate data and building parameters. The main goal of the model is to predict natural ventilation hours and hourly ventilation flow rate. In fluid model, formula of single-sided natural ventilation by coupling wind pressure and temperature difference was used to calculate air flow rate. Accordingly, the paper analyzed four typical cities in different climate region in China and calculated pressure difference Pascal hours (PDPH). The results show that single-sided ventilation has fewer adaptive comfort hours than two-sided ventilation and much less ventilation volume. This model provided quantitative information for early stage architectural natural ventilation design and building energy efficiency evaluation. [ABSTRACT FROM AUTHOR]