Search Results (87)

As a densely populated area, college student dormitories consume a large amount of electricity every year to heat the domestic hot water used by students. Applying solar energy to hot water systems can effectively alleviate this situation. This paper first conducts a simulation of the hot water load and the calculation of the available area of the solar roof in a dormitory building of a certain university. Then, different solar-coupled air source heat pump systems were designed, and simulation models of the two systems were established. The thermal performance parameters and solar energy utilization of the two systems were discussed, and the energy efficiency, economy, and environmental protection of the two systems were analyzed. The results show that after coupling with the solar collector, the system operation time is shortened by 26.2%, the annual performance coefficient is 3.4, which is 0.8 higher than that of the original system, and the annual heating energy consumption is reduced by 24.4%. In contrast, the annual energy self-sufficiency rate of the photovoltaic coupled with air source heat pump system is 94.6%, achieving nearly zero energy consumption for heating. Full article

Driven by the global energy transition and China’s dual-carbon targets, Passive ultra-low-energy buildings are a key route for carbon reduction in the construction sector. This study addresses the high energy demand of office buildings and the limited suitability of current efficiency codes in the hot-summer/cold-winter, high-humidity zone of central and southern Anhui. Using multi-year climate records and energy-use surveys from five cities and one scenic area (2013–2024), we systematically investigate climate-adaptive passive-design strategies. Climate-Consultant simulations identify composite envelopes, external shading, and natural ventilation as the three most effective measures. Empirical evidence confirms that optimized envelope thermal properties significantly curb heating and cooling loads; a Huangshan office-building case validates the performance of the proposed passive measures, while analysis of a near-zero-energy demonstration project in Chuzhou yields a coordinated insulation-and-heat-rejection scheme. The results demonstrate that region-specific passive design can provide a comprehensive technical framework for ultra-low-energy buildings in transitional climates and thereby supporting China’s carbon-neutrality targets. Full article

This study evaluates the performance degradation of spray rigid polyurethane foam (RPUF) insulation on reservoir dam structures under multi-physics coupling conditions. Focusing on characteristic environmental exposures in Hot Summer and Cold Winter (HSCW) climate zones, accelerated aging tests simulating coupled temperature–humidity effects were conducted to comparatively analyze the thermal resistance and durability evolution between unprotected and encapsulated RPUF configurations. Scanning electron microscopy (SEM), infrared spectroscopy (IR), and other methods were used to characterize and analyze the structure of RPUF. Research has shown that in HSCW climate zones, the thermal conductivity of RPUF gradually increases with the number of degradation cycles, and the insulation performance decreases, mainly due to the damage of the pore structure caused by temperature aging and the combined effect of moisture absorption aging. In comparison, the RPUF after protection can effectively slow down the rate and degree of decline of its insulation performance. On this basis, a time-varying prediction model for the thermal conductivity of RPUF under long-term service in HSCW climate environments was fitted, providing a scientific basis for the durability evaluation of reservoir dam insulation. Full article

In the context of global energy challenges, adaptive shading systems have emerged as pivotal components in building energy efficiency research. This study systematically evaluates critical performance factors influencing energy efficiency in adaptive shading systems for buildings located in hot summer and cold winter climate zones, with a focus on parametric optimization of shading panel configurations. Through field measurements, orthogonal experimental design, and numerical simulations, this investigation centers on the adaptive shading system of a nearly zero energy building (NZEB). Four critical parameters—shading panel width, panel-to-window clearance, window-to-wall ratio (WWR), and surface reflectance—were rigorously analyzed through orthogonal experimental methodology and DesignBuilder^® simulations. This study identifies WWR and shading panel reflectance as the key factors for optimizing adaptive shading systems. Among the scenarios evaluated, the highest energy efficiency was achieved with horizontal shading devices on the south façade, featuring a panel width of 500 mm, a minimum clearance of 150 mm, a WWR of 55%, and a surface reflectance of 0.4. Under this configuration, the annual energy consumption was reduced to 8312.37 kWh, corresponding to a 2.1% decrease (8.31 MWh) in total site energy consumption (TSEC). This research provides valuable insights for energy-efficient building design in hot summer and cold winter regions, and supports the broader adoption of adaptive shading systems. Full article

This study investigated the synergistic effects of vegetation configurations and microclimate factors on seasonal thermal comfort in a semi-enclosed university courtyard in Wuhan, located in China’s Hot Summer and Cold Winter climate zone (Köppen: Cfa, humid subtropical). By adopting a field measurement–simulation–validation framework, spatial parameters and annual microclimate data were collected using laser distance meters and multifunctional environmental sensors. A validated ENVI-met model (grid resolution: 2 m × 2 m × 2 m, verified by field measurements for microclimate parameters) simulated 15 vegetation scenarios with varying planting patterns, evergreen–deciduous ratios (0–100%), and ground covers. The Physiological Equivalent Temperature (PET) index quantified thermal comfort improvements relative to the baseline. The optimal grid-based mixed planting configuration (40% evergreen trees + 60% deciduous trees) significantly improved winter thermal comfort by raising the PET from 9.24 °C to 15.42 °C (66.98% increase) through windbreak effects while maintaining summer thermal stability with only a 1.94% PET increase (34.60 °C to 35.27 °C) via enhanced transpiration and airflow regulation. This study provides actionable guidelines for climate-responsive courtyard design, emphasizing adaptive vegetation ratios and spatial geometry alignment. Full article

With the intensification of climate challenges driven by rapid urbanization, the microclimate and thermal comfort of residential blocks have attracted increasing attention. Current research predominantly focuses on isolated morphological factors—such as building orientation, layout patterns, and height-to-width ratios—while neglecting the synergistic effects of multifactorial spatial configurations on outdoor thermal comfort. This study addresses this gap by analyzing 36 residential block samples in Wuhan, a representative city in a hot-summer and cold-winter (HSCW) region. Utilizing the Honeybee plugin in Grasshopper (GH) alongside the Universal Thermal Climate Index (UTCI), we simulate outdoor thermal environments to identify critical influencing elements. The results reveal how multifactor interactions shape thermal performance, providing evidence-based design strategies to optimize microclimate resilience in high-density urban contexts. This work advances the understanding of spatial morphology–thermal dynamics and offers practical insights for sustainable residential planning. This study systematically investigates the thermal performance of residential blocks through parametric prototyping and seasonal simulations. Sixteen morphological prototypes were developed by combining four building layout typologies (arrayed, staggered, enclosed, and hybrid) with three critical variables: the height-to-width ratio (HWR), building orientation deviation angle (θ), and sky visibility factor (SVF). Key findings reveal the following: (1) the hybrid layout demonstrates superior annual thermal adaptability when integrating fixed orientation (θ = 0°), moderate H/W = 1, and SVF = 0.4; (2) increased H/W ratios enhance thermal comfort levels across all layout configurations, particularly in winter wind protection; and (3) moderate orientation deviations (15° < θ < 30°) significantly improve microclimate performance in modular layouts by optimizing solar penetration and aerodynamic patterns. These evidence-based insights provide actionable guidelines for climate-responsive residential design in transitional climate zones, effectively balancing summer heat mitigation and winter cold prevention through spatial configuration optimization. Full article

Condensation assessment of a residential building in Changsha, China-located in the hot summer and cold winter climate zone-was conducted during the Plum Rain Season (PRS) using Energy Plus simulations and field measurements. Window-opening behaviour significantly influences indoor air quality and thermal comfort. This study specifically examines how window-opening patterns, including opening duration and opening degree, affect interior surface condensation risk in a rural residential building during PRS. Results indicate that window operational status (open/closed) exerts a dominant influence on condensation risk, while varying window opening degrees during identical opening duration showed negligible differential impacts. Critical temporal patterns emerged: morning window openings during PRS should be avoided, whereas afternoon (15:00–18:00) and nighttime (18:00–06:00) ventilation proves advantageous. Optimisation analysis revealed that implementing combined afternoon and nighttime ventilation windows (15:00–18:00 + 18:00–06:00) achieved the lowest condensation risk of 0.112 among evaluated scenarios. Furthermore, monthly-adjusted window operation strategies yielded eight recommended ventilation modes, maintaining condensation risks below 0.11 and providing occupant-tailored solutions for Changsha’s PRS conditions. These findings establish evidence-based guidelines for moisture control through optimised window operation in climate-responsive building management. Full article

Tree-lined spaces as informal communication areas and important pathways for pedestrians are the second largest zones on university campuses, and they have a large impact on the microclimate. At present, the effects of the spatial form for tree-lined boulevards on microclimates have not been investigated. Thus, this study applied experimental and simulation methods to investigate the effects of tree-lined boulevards on microclimates in hot summer and cold winter regions. The main meteorological parameters including air temperature, relative humidity, wind speed, and solar radiation of the boulevard were obtained by experiments. Furthermore, the experimental data as a boundary condition were input into ENVI-met software to investigate the effects of the aspect ratio and canopy diameter of double-row open-canopy boulevards on microclimate regulation. The results showed that when the aspect ratio was reduced from 1.5 to 0.9, the temperature and UTCI increased by 0.047 °C and 0.21 °C, while relative humidity decreased by 0.227%. Decreasing the aspect ratio can effectively improve the microenvironment. As the canopy diameter increased from 7 m to 11 m, the temperature and UTCI of the boulevard space decreased by 0.064 °C and 0.45 °C, while relative humidity increased by 0.245%. An increase in canopy diameter is unfavorable to the improvement of microclimates. This study aims to provide a scientific basis for the design and improvement of tree-lined boulevards on university campuses. Full article

Older people are the most vulnerable to extreme heat and cold events, and understanding their thermal comfort requirements is an important component for the design of healthy buildings. There are, however, very few predictive thermal comfort models for older populations. The aim of this paper was to validate the newly developed MPMV model for older people using thermal sensation data collected in climatic chambers and field studies in urban and rural buildings under various climate zones. Besides the six customary physical parameters governing thermal perception, the model accounts for additional factors covering heat retrieval from or heat addition to the body core and adjustment constants for regulatory sweating rate and non-shivering thermogenesis, which are important for the thermal adaptation of people in real settings. The model predictions show good agreement with measurement in climate chambers, with an overall RMSE = 0.44. Similarly, the model reproduces field measurement with a high degree of accuracy in 71% of the studies, with RMSE = 0.52. The major differences were observed in urban and rural residences during the winter of cold climates and summer of hot climates. These discrepancies could be attributed to unreported factors, such as the transient effects, misestimation of personal input data, and seasonal adaptation of residents. Full article

In order to assess the spatial and temporal characteristics of the urban thermal environment in Zhengzhou City to supplement climate adaptation design work, based on the Landsat 8–9 OLI/TIRS C2 L2 data for 12 periods from 2019–2023, combined with the lLocal climate zone (LCZ) classification of the urban subsurface classification, in this study, we used the statistical mono-window (SMW) algorithm to invert the land surface temperature (LST) and to classify the urban heat island (UHI) effect, to analyze the differences in the spatial distribution of thermal environments in urban areas and the aggregation characteristics, and to explore the influence of LCZ landscape distribution pattern on surface temperature. The results show that the proportions of built and natural landscape types in Zhengzhou’s main metropolitan area are 79.23% and 21.77%, respectively. The most common types of landscapes are wide mid-rise (LCZ 5) structures and large-ground-floor (LCZ 8) structures, which make up 21.92% and 20.04% of the study area’s total area, respectively. The main urban area’s heat island varies with the seasons, pooling in the urban area during the summer and peaking in the winter, with strong or extremely strong heat islands centered in the suburbs and a distribution of hot and cold spots aggregated with observable features. As building heights increase, the UHI of common built landscapes (LCZ 1–6) increases and then reduces in spring, summer, and autumn and then decreases in winter as building heights increase. Water bodies (LCZ G) and dense woods (LCZ A) have the lowest UHI effects among natural settings. Building size is no longer the primary element affecting LST as buildings become taller; instead, building connectivity and clustering take center stage. Seasonal variations, variations in LCZ types, and variations in the spatial distribution pattern of LCZ are responsible for the spatial differences in the thermal environment in the study area. In summer, urban areas should see an increase in vegetation cover, and in winter, building gaps must be appropriately increased. Full article

Localized heating systems are an effective approach to improve thermal comfort while reducing energy consumption in a cold indoor environment. Furthermore, localized heating devices have found widespread application in the hot-summer and cold-winter zones of China. This study investigates the heating characteristics of the local heating device in a low-temperature environment, as well as its effects on subjective perception and physiological responses, and develops a personalized control system for the device based on the experimental findings. We conducted experimental tests and questionnaires in a test room with air temperature set at 12 °C and 14 °C and a relative humidity of 55%. A total of six experimental conditions were designed using five types of heating equipment (heating wrist straps, heating insoles, heating leg straps, warm air blower, electric radiant heater), each employing different heat transfer methods. The results demonstrate that the head, hands, legs, and feet are susceptible to feeling cold in a low-temperature environment, and the use of a warm air blower and electric radiant heater can significantly enhance the thermal sensation of these parts, improve thermal acceptability, and raise local skin temperature. The electrocardiogram data indicate that heart rate variability can be utilized to assess thermal sensation in a cold environment with localized heating. Additionally, the relationship between thermal response and skin temperature was investigated, leading to the development of a control strategy for the local heating device in a low-temperature conditions. Full article

Residential buildings consume significant amounts of energy worldwide. Traditional courtyard houses have substantial energy-saving potential due to their low energy consumption and high climate adaptability, which has heightened interest in their climate-responsive design. In recent years, extensive research on traditional houses has been conducted in China, indicating significant variations in energy performances among traditional courtyards within hot-summer and cold-winter climate zones. Therefore, this study, based on research conducted on traditional courtyard houses in the Xuzhou area and utilizing Ecotect and Phoenics ecotechnology software for simulation analysis, comparatively examines the factors influencing energy consumption to assess the energy-saving potential of these houses in hot-summer and cold-winter climate zones. Research has indicated that when traditional Xuzhou courtyard houses meet certain criteria—including an orientation of 20° east of south for the main building, width-to-depth ratio of 2:1, roof slope of 35°, courtyard width-to-depth ratio of 1.7:1, use of branch pick windows, building height of 4.5 m, and a specific window-to-wall ratio—they achieve optimal climate adaptability. This study proposes dimensions for traditional residential buildings suited to the Xuzhou climate and explores their practical application, providing targeted optimization and retrofitting suggestions to support sustainable architectural and ecological development. Full article

In the conditions of growing anthropogenic pressure, aquatic ecosystems all over the world are subject to transformation, expressed in the growth of eutrophication, increase in acidity, changes in water exchange, etc. In the region of Eastern Siberia we studied, located in Yakutia in the middle reaches of the Lena River basin, there is a significant population growth accompanied by advancements in agriculture and public utilities. The region is rich in small lakes, which have been under pressure from human activities for the past few decades. The studied region is located in the permafrost zone and is characterized by severe climatic conditions, cold long winters, short hot summers, and a short ice-free period on reservoirs. We studied 17 lakes of various genesis, with varying degrees of anthropogenic pressure, located in the largest city of the region, small villages, and at different distances from them. Previous studies have established that cyanobacteria constitute the phytoplankton main group in these lakes during the summer period. Therefore, we selected them as the focus for our bioindication analysis. An integrated assessment of the bioindication properties of cyanobacteria, along with chemical water parameters, was undertaken using statistical mapping methods, JASP, and Redundancy Analysis (RDA). This analysis revealed the impact of urbanized areas, characterized by a decrease in pH, runoff of nitrogen compounds, and an increase in organic matter. Despite the cryolithozone harsh conditions, in small lakes of urbanized areas, cyanobacteria exhibit their competitive advantages within the plankton community. The prospect of continuing our work is associated with the need to determine the risk of cyanoHAB development since potentially toxic cyanobacteria have a mass development in a number of lakes. Full article

With the implementation of the rural revitalization strategy, rural residences have become an essential component of China’s building energy conservation efforts. However, most existing research has focused more on urban buildings, with less attention given to rural residences. This study, taking rural residential buildings (RRBs) in the hot summer and cold winter zones in China as an example, proposes a more precise, two-stage optimization design framework using Rhino-Grasshopper for the overall optimization of RRBs. First, field surveys and numerical analysis of collected rural residential design drawings were conducted to clarify spatial characteristics and air conditioning usage. The parametric optimization design of RRBs was then conducted in two steps. The first step involves room function positioning, where spatial geometric models are established. Annual dynamic simulation analyses of AC (air conditioning) and AL (artificial lighting) energy consumption are performed to obtain energy intensity distribution maps. Based on the principle that “space with higher energy consumption is set in the location with lower energy consumption intensity” and the habit of functional space distribution, room function positioning, and adjustments are made. In the second step, the SPEA-2 genetic algorithm was applied for multi-objective optimization of room width, depth, WWR (window-to-wall ratio), SHGC (solar heat gain coefficient), and VLT (visible light transmittance), all based on the logical relationships of the building structure. The final Pareto front solution sets were obtained by multi-objective optimization simulation (MOO). A typical three-bay RRB was selected for application in this study, and the optimized design led to a total energy savings rate of 11% in annual AC and AL energy consumption. Full article

Traditional concrete buildings exhibit low energy consumption and high heat loss, which results in a larger environmental problem. Precast insulation walls are proposed for strengthening thermal insulation efficiency and mitigating heat loss. Numerous studies have investigated the thermal performance of insulation walls over the past decades. However, gaps remain in practical engineering applications. This study aims to bridge these gaps by providing practical design recommendations based on experimental research. Nine different types of precast insulation walls were tested to examine the thermal performance, and the parameters of the insulation material, insulation form, insulation layer thickness, and concrete rib width were investigated. Then, numerical models of these walls were developed for simulating the thermal performance of the tested specimens. Finally, a six-story student apartment model using designed walls was developed to assess energy consumption in two distinct climate zones: the hot summer and cold winter zone of Changsha City, and the cold zone of Harbin City. The results indicate that the precast insulation wall with external insulation form shows better thermal performance than the sandwich insulation form. It is recommended to use precast insulation walls with 50 mm extruded polystyrene (XPS) external thermal insulation form in Changsha City and 80 mm XPS external thermal insulation form in Harbin City. Furthermore, buildings using precast insulation walls can significantly reduce energy consumption by 49.25% in Changsha and 49.38% in Harbin compared to traditional concrete wall buildings. Based on these findings, suitable design suggestions for this precast concrete wall panel building composed of insulation walls are given. Full article