Search Results (464)

This study investigates an integrated ecological strategy to reduce electricity consumption in semi-collective housing located in the hot–arid climate of Biskra, Algeria, a region with high solar potential. The research combines photovoltaic (PV) electricity generation with passive thermal insulation using a locally sourced bio-based material derived from date palm fibers. The case study includes 104 dwellings within a residential complex of 350 units. Results show that monocrystalline PV panels (350 W) can produce approximately 479 kWh/panel/year. To meet the total annual electricity demand (504,712 kWh), around 1052 panels are required, corresponding to 1714 m² (13.8%) of the available building envelope. This installation area demonstrates the significant photovoltaic potential of the residential complex under hot–arid climatic conditions. Thermal analysis indicates that integrating a 5 cm palm fiber insulation layer increases thermal resistance from 2.06 to 2.62 m²·°C/W and reduces heat flux from 2.18 to 1.72 W/m². This improvement decreases conductive heat transfer through the envelope by approximately 21%, while numerical simulations indicate indoor temperature reductions of 4–8 °C during summer conditions. These findings demonstrate that combining PV systems with bio-based insulation significantly enhances energy efficiency and thermal comfort in residential buildings under desert climatic conditions. Full article

This paper investigates the potential of localized air-curtain microclimate control to reduce HVAC energy consumption in electric vehicles while maintaining occupant thermal comfort. The study compares conventional full-cabin cooling with driver-focused and passenger-focused air-curtain configurations under controlled ambient conditions of 32 °C. The experimental framework combines analytical airflow and heat-transfer modeling with comparative HVAC performance evaluation using power consumption, time to reach thermal comfort, and Predicted Mean Vote (PMV) analysis. The results show that the air-curtain configurations reduce HVAC power consumption from 3.2 kW for conventional cooling to 2.3 kW and 2.5 kW for the driver- and passenger-focused configurations, corresponding to energy savings of approximately 22–28%. In addition, localized airflow significantly accelerates thermal comfort attainment, reducing stabilization time from 8 min to 4–5 min while maintaining PMV values within acceptable comfort limits. The findings demonstrate that occupant-centered air-curtain microclimate strategies can improve HVAC energy efficiency, reduce auxiliary energy demand, and support more sustainable and range-efficient operation of next-generation electric vehicles. Full article

Textile membrane systems are increasingly used in sports halls because of their low structural weight, rapid assembly, and ability to span large areas. Their operational performance, however, is strongly affected by local climate conditions, envelope configuration and the limited thermal inertia of membrane materials. This study presents a comparative EnergyPlus-based assessment of textile membrane sports halls in six representative climate contexts: Helsinki, Berlin, Niš, Barcelona, Dawadmi and Bangkok. A conventional masonry hall was used as the reference case and compared with a single-layer PVC-coated polyester membrane system and double-layer membrane systems with air gaps of 0.4, 0.5 and 0.6 m, including mechanically ventilated air-cavity variants. The assessment combines four performance indicators: annual operational energy demand, carbon emissions, indicative global cost and thermal comfort expressed through Fanger’s Predicted Percentage of Dissatisfied (PPD) index. The results show that the dominant energy demand is climate-dependent, with heating prevailing in cold climates and cooling becoming decisive in hot-arid and hot-humid climates. Double-layer cases usually show lower operational energy demand and lower associated carbon dioxide emissions than the single-layer membrane case. This improvement, however, is not uniform; it depends on the climatic setting and on the width of the air gap. The comfort results lead to a similar but more limited conclusion. Although PPD is reduced in the double-layer configurations, the values remain above conventional comfort acceptance levels in all tested cases. The double-layer membrane should therefore be understood as a measure that reduces thermal dissatisfaction, not as a complete comfort solution. The economic assessment indicates that membrane systems have substantially lower initial capital costs than masonry construction, while their long-term performance depends on operational energy costs, membrane replacement assumptions and the selected analysis horizon. The study provides a climate-specific comparative framework for early-stage envelope selection in textile membrane sports halls, emphasizing that energy demand, carbon emissions, cost and thermal comfort should be considered together rather than as separate outputs. Full article

This paper presents a comprehensive evaluation of control strategies for a highly energy-efficient plus-energy terraced housing complex equipped with photovoltaic generation, modulating ground-source heat pumps, electrical and thermal energy storage systems, and activation of building thermal mass. The study combines long-term monitoring data, annual simulations, and hardware-in-the-loop (HiL) experiments to assess modulating heat-controlled operation (HC), PV-controlled (PVC), and predictive control strategies, including simple predictive control (SPC) and model predictive control (MPC). The simulation results show that the baseline HC operation already achieves a high load cover factor (LCF), defined as the fraction of total electrical demand covered by local PV generation (direct use + battery discharge) of 65.6% and a seasonal performance factor (SPF) of the central heat pumps of 5.8. PVC increases LCF (71.0%) by shifting heat pump operation toward PV-rich periods but leads to elevated storage temperatures up to 5 K and a reduced SPF of 4.8. MPC further enhances LCF by 4–7 percentage points in simulated and HiL environments. However, its real-world performance is strongly influenced by forecast quality and the limited controllability of the heat pump system. In addition, building thermal mass activation is investigated as a complementary flexibility option. Simulation and monitoring results demonstrate that moderate room temperature set-point (2 K) increases during PV availability significantly improve LCF from 20% to 55% while maintaining thermal comfort. Overall, the findings indicate that in highly efficient plus-energy buildings, robust rule-based strategies combined with thermal mass activation can achieve a large share of the attainable benefits, while the added complexity of MPC must be carefully weighed against practical limitations. Full article

Conventional full-space heating systems waste massive fossil-derived energy on unoccupied indoor areas and cause uncomfortable “warm head, cold feet” issues against sustainable building targets. To fill this gap and advance low-carbon indoor heating solutions for sustainable office development, this study proposes an innovative localized heating terminal combining radiant panels and downward laminar air supply. An experimental platform was established, with twelve testing cases covering varied supply air velocity, supply air temperature and radiant panel temperature to explore its thermal comfort and energy-saving sustainability performance. Experimental results demonstrate that, under the optimal operating condition (0.55 m/s airflow, 23.5 °C supply air, 36 °C radiant panel), the vertical head–foot temperature difference reduces to merely 1.2 °C, far below the 3–5 °C threshold of conventional heating equipment; the draught rate approaches zero to eliminate cold draft discomfort. Critically, 65–75% of total supplied heat concentrates within human-occupied zones, drastically cutting redundant heat loss and advancing building heating sustainability. The terminal features dual working modes: convection contributes 78.7–94.4% of total heat for rapid warm-up while radiant heat maintains stable long-term comfortable surroundings. Such flexible dual-mode design supports sustainable part-load operation matching intermittent office occupancy, making this terminal a feasible low-carbon option for modern sustainable office buildings prioritizing energy efficiency and a healthy indoor environment. Full article

Traditional evaluation indicators, including average air temperature, flow field distribution, and breathing-zone temperature, fail to fully characterize the actual effect of solar radiation on passenger thermal comfort. Therefore, based on the Fiala human physiological thermoregulation model and the Berkeley–Zhang thermal comfort evaluation criterion, this study develops a coupled simulation method for the objective evaluation of passenger thermal comfort. On this basis, the influence of front windshield solar radiation transmittance on passenger thermal comfort is preliminarily investigated. The results reveal that when the glass transmittance decreases from 0.52 to 0.37, the steady-state average cabin air temperature declines by approximately 0.5 °C, and the overall thermal comfort value increases from 0.67 to 1.2. In addition, the left crus receives the maximum solar radiation intensity, resulting in the poorest local thermal comfort. This verifies the feasibility and effectiveness of the method and provides a basis for the thermal comfort research of the vehicle cabin. Full article

Amid rapid urbanization and the expansion of higher education campuses, the physical and psychological well-being of college students has garnered increasing scientific attention. Although outdoor activities are crucial for student health, participation rates are heavily constrained by outdoor thermal comfort (OTC). This study investigates the OTC of university students in Xi’an, China, utilizing the Universal Thermal Climate Index (UTCI) to assess thermal perceptions across four distinct open spaces and to propose localized bioclimatic design interventions. The results reveal four key findings: (1) The meteorological correlates of thermal sensation vary significantly by spatial typology; relative humidity (RH) and air temperature (Ta) dominate in sunken spaces (HB), whereas solar radiation (G), globe temperature (Tg), and wind velocity (Va) are the primary correlates in sports squares (CS) and activity squares (SH). (2) Thermal benchmarks exhibit remarkable spatial heterogeneity during summer. The Neutral UTCI (NUTCI) varied widely from 17.11 °C in hard-paved squares (SH) to 26.13 °C in shaded bridge areas (JG), with the corresponding neutral zones (NUTCIR) shifting accordingly. (3) Significant variations in thermal adaptation exist even within identical macro-climates, underscoring the necessity of microclimate-specific design. (4) Targeted bioclimatic strategies—including optimized vegetation deployment, shading structures, localized sprinkler systems, and permeable paving—are proposed. These findings provide actionable guidelines for urban planners and landscape architects to optimize campus environments, thereby encouraging outdoor engagement and enhancing student well-being. Full article

In coastal residential areas, the combined effects of high temperature, high humidity, and weak wind conditions during summer intensify outdoor heat exposure and reduce pedestrian thermal comfort. To investigate the influence mechanisms of tree height and spatial layout on pedestrian-level thermal comfort, this study selected a typical residential community in Chengyang District, Qingdao, as the research site. Based on field meteorological observations, an ENVI-met model was established and validated. Using the existing composite greening scenario as the baseline, three tree layout types (row, cluster, and free layouts) and four height scenarios (4 m, 6 m, 8 m, and 10 m) were configured to quantitatively compare variations in physiological equivalent temperature (PET) under different planting schemes. The results indicate that tree configuration significantly affects summer thermal comfort. Its regulatory mechanism is governed not only by air temperature reduction but also by shortwave radiation interception, longwave radiation accumulation, and shading continuity. Although low-to-medium height trees can reduce local air temperature through transpiration, their limited canopy height and shading continuity restrict their ability to effectively attenuate direct shortwave radiation at pedestrian level, and in some cases may even increase mean radiant temperature (Tmrt) and PET. In contrast, 10 m tall trees arranged in row and cluster layouts can form continuous shaded cores, with the 10 m cluster layout demonstrating the best overall performance by significantly reducing Tmrt and PET. The free layout, characterized by dispersed canopies and fragmented shading, provides relatively limited thermal comfort improvement. The findings suggest that residential greening optimization should strengthen the coordination between tree height, canopy structure, and activity spaces. Tall trees should be prioritized in children’s play areas, elderly resting areas, residential entrances, main pedestrian pathways, and west-facing sun-exposed zones, while integrating building shadows and road orientation to create a continuous yet not overly enclosed shading network, thereby enhancing summer thermal adaptability in residential areas. Full article

Urban green spaces (UGSs) are increasingly recognised as critical infrastructure for mitigating climate extremes and promoting public health; indeed, the microclimatic mechanisms through which vegetation structure translates into measurable improvements in human comfort at the neighbourhood scale are of significant interest, particularly in the context of new urban developments. This study examines the cooling effects of an urban redevelopment project in the Marconi district of Imola, Italy, using ENVI-met (Version 6.0.0, ENVI-met GmbH, Essen, Germany) simulations to compare ex ante (current) and ex post (planned) scenarios under extreme heat conditions. Physiological Equivalent Temperature (PET) was computed at the pedestrian level for both standard adult and elderly models to assess spatial patterns of thermal comfort. The results demonstrate that tree canopies are the primary determinant of local cooling, with newly planted trees reducing PET by up to 3.5 °C at the core of the regenerated block and by 1–2 °C along adjacent pavements, while grass and low vegetation provided negligible mitigation. However, new buildings generated localised warming bands of 0.5–2 °C along façades, revealing a trade-off between densification and outdoor liveability. Elderly populations experienced slightly stronger thermal stress near buildings, highlighting spatial concentrations of vulnerability. These findings reinforce the need to prioritise tree planting and canopy management as core climate adaptation strategies, while simultaneously addressing near-building heat accumulation through integrated design approaches such as façade greening and ventilation preservation. The study demonstrates the value of spatially explicit microclimate simulation for evidence-based urban planning, contributing to the development of sustainable and liveable urban environments. Full article

(1) Background: The global expansion of teleworking has increased concern regarding musculoskeletal pain associated with home-based working conditions. This study quantified the prevalence of musculoskeletal pain among Brazilian teleworkers and explored ergonomic and environmental factors associated with the distribution of physical symptoms and the multisite pain burden. (2) Methods: A cross-sectional survey was conducted between June and August 2024, analyzing 184 valid responses from teleworkers across various professional sectors. Data were collected via an online questionnaire assessing sociodemographic characteristics, workstation ergonomics, and musculoskeletal symptoms using the Nordic Musculoskeletal Questionnaire (NMQ). Statistical analyses included Pearson’s chi-square tests, logistic regression, and exploratory Random Forest modeling to prioritize predictors. (3) Results: Musculoskeletal pain was reported by 74% of participants, with the lower back (40.8%), neck (36.4%), and upper back (30.4%) being the most frequently affected anatomical regions. The primary ergonomic and environmental factors associated with pain reports included discomfort with the desk and mouse, suboptimal thermal comfort, and prolonged sitting. Odds ratios demonstrated strong statistical co-occurrence between recent and 12-month pain reports, particularly for the shoulders, reflecting overlapping recall indicators rather than temporal symptom progression. (4) Conclusions: Musculoskeletal pain is highly prevalent among Brazilian teleworkers, showing clear links to localized workstation inadequacies and overlapping short- and long-term symptom reporting. These findings highlight the need for targeted institutional occupational health policies, such as ergonomics training and adjustable furniture provision, while future longitudinal research remains essential to confirm causal pathways. Full article

Urban street canyons exert a critical influence on local microclimates; however, the dynamics of mixed convective airflow under unsteady wind and thermal forcing remain poorly quantified. This study systematically investigates the spatiotemporal characteristics of airflow within symmetric and asymmetric street canyons through integrated long-term field measurements and complementary CFD simulations. Field data collected over 120 monitoring days at the Weishui Campus of Chang’an University were analyzed using the Levenberg–Marquardt nonlinear curve-fitting algorithm. The analysis demonstrates that sine functions accurately represent diurnal surface temperature variations during consecutive clear sky periods, whereas polynomial functions of varying orders are required to characterize meteorologically complex episodes, including cold-wave cooling and seasonal transitions. Ambient wind patterns outside the canyon were further classified into two characteristic variation modes: stepwise and gradual. Complementary unsteady RANS simulations, with wall boundary conditions derived directly from the fitted field data, reveal that canyon geometry and meteorological forcing jointly govern the evolution of airflow structures and thermal distributions across seasons. In the symmetric canyon, the flow transitions from complex multi-vortex activity in spring and summer to a more stable regime in autumn, with two well-defined counter-rotating vortices emerging during winter cold-wave events. In the asymmetric canyon, strong summer solar heating sustains a dominant leeward vortex with a strengthening secondary structure, whereas winter cold wave intrusion generates a hierarchically nested vortex system in which secondary and tertiary vortices progressively develop and detach. By coupling empirical surface temperature functions with CFD boundary conditions, this study advances the precision of predictive microclimate models and provides an evidence-based framework for optimizing street canyon geometry to enhance ventilation performance, energy efficiency, and outdoor thermal comfort. Full article

Vernacular settlements in hot–humid regions preserve climate-responsive spatial knowledge, yet evidence on how linked outdoor, transitional, and indoor spaces jointly shape microclimate and thermal comfort remains limited. This study investigates a compact Hakka settlement in southern Jiangxi, China, by integrating field measurements, calibrated simulation, PET-based thermal-comfort assessment, and parametric scenario comparison to examine microclimatic differentiation across cold alleys, patios, halls, semi-open interfaces, and interior rooms. The results reveal clear microclimatic gradients across the linked vernacular spatial sequence. During the summer afternoon peak, cold alleys reduced air temperature by approximately 2.5 °C and PET by approximately 8.5 °C relative to ordinary streets, while semi-enclosed spaces adjacent to patios reduced air temperature by approximately 4.0 °C but increased relative humidity by 8–12%, indicating a cooling–moisture trade-off. Measured and simulated air temperature and wind speed showed satisfactory agreement and reproduced the main thermal and ventilation hierarchy across the connected spaces. Parametric comparison further identified case-based geometry-performance tendencies under the tested boundary conditions: within the tested cold-alley scenarios, widths of approximately 0.8–1.4 m combined with an H/W ratio close to 3:1 showed relatively favorable airflow-temperature performance in terms of shading continuity, moderated airflow, and reduced summer thermal exposure. The findings suggest that thermal comfort in compact hot–humid vernacular settlements depends on radiant-load reduction, moderated ventilation, and thermal buffering rather than on ventilation enhancement alone. Beyond the case-specific evidence, this study contributes a sequence-based, locally calibratable approach for preliminary retrofit appraisal in comparable compact hot–humid vernacular settlements. Full article

Indoor temperature time series in district-heating buildings are often contaminated by anomalies embedded in nonstationary, multiscale thermal dynamics. This study proposes a hybrid Empirical Wavelet Transform and Long Short-Term Memory (EWT-LSTM) framework for adaptive anomaly detection and localized reconstruction. Evaluated on 15 min interval data from 45 residential units over a 112-day heating season, the framework operates via a highest-frequency branch for anomaly detection and a full-modal branch for signal repair. Quantitative results show that the EWT Highest-Frequency LSTM (EWT(HF)-LSTM) achieved the best anomaly discrimination among decomposition variants with an average F1-score of 0.531. For anomaly repair, the full EWT-LSTM produced the highest fidelity with a localized Root Mean Square Error ($RMS{E}_a$) of 0.818 °C. Furthermore, thermal comfort validation demonstrated that EWT-LSTM successfully prevented the severe comfort degradation of up to −82% in Exceeded Degree-Hours caused by unstable Empirical Mode Decomposition (EMD)-based reconstructions. These concrete results confirm that the proposed framework effectively provides clean, physically coherent temperature data for downstream district heating operations. Full article

The construction sector accounts for approximately 36% of global final energy consumption and close to 40% of total CO₂ emissions, making it a primary target of international climate policy. Despite this growing attention, the indigenous building traditions of the Ecuadorian Andes remain virtually absent from the international scientific literature on vernacular sustainability. This study presents a systematic field documentation and bioclimatic assessment of vernacular bahareque dwellings in the Kichwa-Saraguro community of Ilincho, canton of Saraguro, province of Loja, Ecuador (2700 m a.s.l.). A field survey of 30 dwellings identified five morphological typologies—I-1P, I-2P, 2B, L, and C—with typology C, a compact C-shaped block with a three-sided portal, accounting for 53.3% of the sample. A structured multi-criteria framework of 48 bioclimatic indicators distributed across eight categories, adapted to the cold-temperate mountain climate of the study area, was applied to quantify each typology’s bioclimatic performance. All typologies exceeded 75% overall compliance on the global Bioclimatic Performance Index (BPI), with typology C achieving the highest value (88.5%). Categories F (Materials and construction) and H (Cultural and social aspects) scored 100% across all typologies, reflecting system-level properties of the bahareque constructive system rather than morphological differences between typological variants; a supplementary morphological BPI restricted to Categories A–E and G is reported. An exploratory, uncalibrated energy simulation of typology C provided indicative evidence consistent with the expected thermal behavior of a high-thermal-mass bahareque envelope, with simulated minimum temperatures in the sleeping area within the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) 55-2013 comfort range (T-min 18.80 °C). Collectively, these findings contribute quantified bioclimatic documentation of vernacular bahareque architecture in Ilincho, identifying attributes—encompassing solar control, spatial compactness, high-thermal-mass envelope performance, and use of locally sourced low-embodied-energy materials—that may inform sustainable rural housing discussions in the Ecuadorian Andes and comparable high-altitude mountain contexts. Its documentation in the indexed scientific literature constitutes a step toward recognizing this constructive heritage as a practical resource for low-carbon building policy. Full article

Prefabricated buildings offer high industrialization, construction efficiency, and sustainability benefits, making them particularly well suited for adverse construction conditions. As railway networks expand into western China’s high-altitude regions, prefabricated structures have been increasingly adopted for living quarters along railway lines in cold, high-altitude areas. This study proposes a method that accounts for thermal-bridge effects by using the average thermal transmittance coefficient K_m and the linear thermal transmittance ψ calculated via two-dimensional steady-state simulations with PTemp software. The approach was validated against 48 h field measurements from a prefabricated building in Weinan: the model incorporating thermal bridges reduced the mean temperature error from 15.6% to 7.74%, confirming its accuracy. Using DeST software, the indoor thermal environment of a railway living-quarter building in the Ganzi region was simulated. Results show that south-facing rooms have an average temperature 2.3 °C higher than north-facing rooms and a 17.74% lower annual discomfort time. Building orientation, south-facing window-to-wall ratio, and envelope thermal transmittance significantly affect overall indoor temperature and energy consumption. The optimal orientation range is 15–45° west of south, and the least favorable range is 135–165°. A south-facing WWR of 0.35–0.45 and an exterior wall insulation thickness of 60–120 mm are recommended. For the typical high-altitude locations Litang, Batang, Qamdo, Nyingchi, Lhasa, and Ganzi, region-specific optimal parameters are provided: exterior wall K_m values range from 0.10 to 0.65 W/(m²·K) and window K values from 1.0 to 3.0 W/(m²·K), depending on the local solar radiation and altitude. These findings offer quantitative design guidance for improving indoor thermal comfort and reducing energy use in prefabricated railway buildings on the western Sichuan and Tibetan plateaus. Full article