Search Results (1,666)

This study developed a calibrated, data-supported energy simulation model for the Arrivals Terminal of Cluj-Napoca International Airport (Romania), addressing challenges in modelling complex building typologies. The objective is to improve the accuracy of predicting energy savings and CO₂ emission reductions, supporting renovation and decarbonization strategies aligned with the 2050 targets. The hourly multizone simulations over one year integrated measured operational data, building documentation, and two types of climate datasets (AMY and TMY). The calibration methodology introduces a “Miscellaneous equipment” variable, representing unmonitored indoor electricity consumption, which is incorporated as an internal heat gain in the thermal balance. Validation against real energy measurements showed high agreement (AMY-based RMSE: 3.13 kWh/m²·yr for thermal energy and 1.57 kWh/m²·yr for electricity; relative errors: 2.3% and 0.5%, respectively). The results demonstrate that calibrated modelling reduces the performance gap and provides a robust alternative to standard design-condition energy assessments, which are inadequate for airport terminals but mandatory for several countries, including Romania. The developed model enhances predictive reliability and can guide energy efficiency measures and investment decisions for similar complex buildings. Full article

The pursuit of carbon neutrality demands advanced low-carbon energy processes and their effective integration into building systems. Ground-source heat pumps (GSHPs) offer a key pathway for decarbonizing heating, yet their cold-climate application is compromised by soil thermal imbalance, which degrades their long-term efficiency. This study proposes and evaluates an innovative air-assisted GSHP system that integrates a vegetable greenhouse with a zoned borehole configuration for seasonal thermal storage to achieve carbon neutrality. The system segregates boreholes into core and peripheral zones to establish a controlled soil temperature gradient, enabling cascaded heat storage and thermal optimization. A comprehensive year-long field test was conducted on a residential building in Harbin, China. The results demonstrate that the system reliably maintains comfortable indoor conditions during severe winters, achieving average seasonal COPs of 3.82 for the heat pump unit and 2.85 for the overall system. The zoned operation strategy successfully generated a significant intra-field soil temperature gradient, with a maximum differential of 5.9 °C between the core and peripheral boreholes during charging. The measured heat extraction-to-storage ratio was 0.598, confirming effective cascaded utilization. From an environmental perspective aligned with low-carbon energy technologies, the system achieves annual savings of 8.66 tons of standard coal and a net CO₂ reduction of 1.3 tons when accounting for regional grid carbon intensity. This research provides empirical validation and practical design guidance for implementing efficient GSHP systems in severely cold regions, thereby contributing substantively to building sector decarbonization. Full article

This study investigated energy-efficient renovation strategies for traditional Thai wooden houses through constructing a demo building and computational assessments. The study addresses the challenges posed by climate change and increasing comfort demands, which have led to increasing use of air conditioning in these historically significant structures. A demo building, designed to replicate a traditional Thai house, was constructed, featuring two rooms: one insulated with magnesium-bonded Typha boards and the other uninsulated. The effectiveness of the insulation was evaluated through hygrothermal simulations and real-time temperature and humidity measurements. The frequently occurring problem of missing measurement data was solved by approximately determining unknown variables through iterative adjustment and comparison of simulation results with measured data. The results indicate that the Typha-insulated room maintained a stable indoor climate, with significantly lower energy consumption from air conditioning than the uninsulated room. Since the air conditioning system was insufficiently powerful in the uninsulated room, it is not possible to quantify the energy savings precisely using measurement technology. However, subsequent hygrothermal simulations enabled a comparative assessment of the energy-saving potential of various measures. Depending on insulation measures and manner of room use, savings of 75–80% could be achieved. Such computational and practical studies can contribute to the preservation of historic buildings. Full article

To meet the energy-saving requirements of user equipment (UE) operating in Radio Resource Control idle/inactive states (RRC_IDLE/RRC_INACTIVE) in the 3rd-Generation Partnership Project (3GPP) 5G-Advanced (5G-A) networks, the New Radio (NR) downlink paging procedure relies on periodic monitoring and frequent synchronization signal block (SSB) measurements, which wastes energy when no paging arrivals occur. Meanwhile, heterogeneous Quality of Service (QoS) constraints make it difficult for fixed-parameter Idle Discontinuous Reception and Paging Early Indication mechanisms (IDRX/PEI) to balance energy, delay, and reliability. This paper develops a UAV-assisted 5G-A paging control framework that maps services into multiple QoS classes and models QoS violation risk and system energy consumption under unified accounting, including UE monitoring/reception energy and unmanned aerial vehicle (UAV) forwarding energy. We then propose a QoS-aware risk-driven paging strategy: an offline Long Short-Term Memory (LSTM) predictor is trained to estimate the time-to-next-arrival (TTNA) of paging events and produce a bounded urgency/risk signal to initialize class-dependent thresholds, while online triggering and QoS-feedback-based threshold adaptation regulate the empirical violation rate toward target constraints under varying loads, enabling a controllable energy–delay trade-off. A simulation-based evaluation is conducted to compare the proposed method with representative baselines (Enhanced Paging Monitoring (EPM), Split Paging Occasion (SPOP), and Predicted Paging Early Indication (PPEI)) and to examine the impact of SSB overhead and UAV relaying on the energy–delay–reliability trade-offs. Full article

Aiming at the problems of high energy consumption and insufficient utilization potential of clean energy in expressway service areas in severe cold and arid desert areas, this paper takes the Xinjiang Kelameili Service Area as the research object to explore the optimal configuration scheme and comprehensive benefits of a photovoltaic system in this specific scenario, providing a technical reference for the energy transformation of transportation buildings in desert areas. The field research method was used to collect measured data of energy consumption and photovoltaic operation in the service area in 2022–2024. The photovoltaic simulation model was constructed using PVsyst 7.3.1 software. The inclination and azimuth parameters were optimized by the control variable method, and the energy savings, carbon emission reductions and economic benefits of the system were calculated by the whole life cycle analysis method. The study found that the total power consumption of the service area in 2024 was 3.661 million kWh, and the actual annual power generation of the existing photovoltaic system was 438 million Wh, accounting for only 12% of the total power consumption. After optimization, the optimal inclination angle of the photovoltaic panel was determined to be 14°, and the azimuth angle was 89°/−89°. Additionally, the maximum annual power generation of the system reached 579 MWh. Throughout the whole life cycle of the photovoltaic system, it is expected to save 1692 tons of standard coal, reduce CO₂ emissions by about 10,311.98 tons, reduce carbon revenue by about 524,800 yuan, and reduce comprehensive income by about 8,097,000 yuan. The static investment recovery period is about 22 years. Reasonable optimization of photovoltaic system configuration can effectively improve the self-sufficiency rate of clean energy in desert expressway service areas. The research results have reference significance for photovoltaic applications in service areas in similar alpine arid areas. Full article

Central business district (CBD) hospitals must sustain reliable pressure relationships in critical rooms while reducing whole-facility carbon under tight space and disruption constraints. We developed an ontology-grounded semantic digital twin that normalizes building automation system (BAS) and building management system (BMS) telemetry into a unified semantic store consistent with Brick Schema, enabling portable asset discovery via query and thereby supporting forecasting, anomaly detection, and multi-objective optimization without dependence on vendor point naming conventions. Whole-facility impacts were verified using International Performance Measurement and Verification Protocol Option C–style measurement and verification with an S0-calibrated baseline model and residual-based savings attribution. Relative to the baseline (S0), the intervention (S3) produced a step increase in the critical-room pressure-compliance pass rate, tighter room-to-corridor differential-pressure (ΔP) control across airborne infection isolation and open room strata, and intent-aligned ventilation delivery (air changes per hour ratio distribution concentrated near unity; p < 0.05 where letter groups differ). Operational-state discrimination improved (AUC 0.649→0.696) and issue-resolution times shortened (left-shifted cumulative distribution function), indicating reduced service burden. Option C verification showed energy residuals shifting negative under S3, consistent with net savings versus baseline expectations. Across progressive maturity (S0→S3), time-to-value and burden fractions decreased, carbon intensity (tCO₂e m⁻²) decreased, long-tail exposure compressed (log-scale horizon), and composite performance indices increased (p < 0.05). These results demonstrate a verifiable pathway to pressure-reliable, decarbonized hospital operations at the whole-facility boundary while making the semantic layer’s utility explicit through query-driven, ontology-grounded asset discovery. We present an IPMVP Option-C–verifiable semantic digital-twin governance framework that links audited operational evidence (telemetry → actions → verification) to whole-facility energy and carbon outcomes while maintaining critical-room pressure-relationship reliability. Optimization benchmarking (including quantum annealing) is used as supporting decision-support evaluation, rather than as the central contribution. Full article

With the increasing integration of low-temperature waste heat systems in aviation, large areas are needed for heat dissipation without causing significant pressure losses. Large-area skin heat exchangers (SHXs) are coming into focus as a possible solution. SHXs based on composite materials offer a promising approach due to their weight-saving potential. This article presents a structure-integrated SHX with a folded core using modern materials and design strategies. An analytical 1D heat transfer model, validated by measurements with temperature-sensitive paints (TSPs), was derived to efficiently identify the optimal parameter set in the design process of an SHX. The model focuses on transverse heat conduction effects in the facesheet for lateral heat distribution and uses these specifically for the overall mass-optimized configuration of the SHX. It is shown that with an optimally selected distance between the cooling channels in the case considered here, up to 12% more energy can be dissipated in relation to the total mass of the SHX. This article concludes with a sensitivity analysis of the analytical model. The influence of heat transfer, thermal conductivity in two spatial directions, and facesheet thickness on the optimal channel spacing is examined. Full article

The technological revolution and industrial transformation led by digital technologies are driving the shift from global value chains (GVCs) to digital global value chains (DGVCs). To address the challenge of global climate change while achieving economic growth, many countries are prioritizing practical energy-saving and emission reduction measures, while simultaneously seeking greater trade gains through participation in digital GVCs and the international division of labor. This study examines whether participation in DGVCs reduces carbon emissions. Using balanced panel data covering 62 countries from 2007 to 2021, we employ a Panel Smooth Transition Regression (PSTR) model to investigate the nonlinear relationship between DGVC participation and CO₂ emissions embodied in digital exports (EEDE). The empirical results reveal an inverted U-shaped relationship, indicating that DGVC participation increases emissions below a digitalization threshold but reduces emissions beyond this threshold. These findings provide new evidence for the dual role of digitalization in shaping trade-related emissions and highlight the importance of stage-specific strategies. Policy implications emphasize that less-digitized economies must prioritize breaking free from carbon lock-in by pursuing green transformation alongside digital expansion. The study deepens the understanding of the trade–environment nexus in the digital era and provides actionable insights for aligning digital economic development with global climate goals. Full article

Traffic congestion not only severely impacts residents’ daily travel quality and increases travel costs, but also triggers traffic accidents, causes environmental pollution, and leads to resource waste. There is a practical need to implement engineering measures simultaneously across multiple intersections to mitigate urban road traffic congestion, which necessitates in-depth research into selecting critical intersection clusters. Based on existing research, the relationship between vehicle emissions and the degree of saturation was derived. The network efficiency evaluation metric was refined using the degree of saturation, and a model linking vehicle emissions to network efficiency was established. A validation experiment was designed using the core road network of Xining City, Qinghai Province, as an example. The results indicate that vehicular exhaust emissions per kilometer are proportional to the saturation degree metric value. The network efficiency metric is inversely proportional to the network’s overall (or average) saturation degree. Vehicular exhaust emissions exhibit an inverse relationship with network efficiency. As the road traffic operational state shifts from congestion to free-flow conditions, for every 1-unit increase in network efficiency value, the average exhaust emissions per vehicle per kilometer decrease by 3.976 kg. Different congestion mitigation node selection schemes correspond to varying total emission reductions during the morning peak. When ranked by the magnitude of increase in network efficiency (from the largest increase to the smallest), the corresponding total morning peak emission reductions gradually decrease in a stepwise manner. According to the $C_{60}^2$ and $C_{60}^3$ experimental results, compared to the worst node cluster selection scheme, the optimal node cluster selection scheme can reduce vehicular exhaust emissions by 4441 kg and 6616 kg, respectively. These findings provide valuable theoretical and practical insights for implementing energy-saving and emission reduction strategies in urban traffic management. Full article

This paper investigates the integration of on-site photovoltaic (PV) systems in the industrial sector under a zero feed-in configuration, where all generated electricity is consumed locally without export to the grid. The analysis follows the current Greek regulatory framework and uses real operating data from an insulation materials manufacturing plant. Twelve months of measured electricity demand were combined with Typical Meteorological Year (TMY) solar data to simulate PV systems of 500, 1000, 1500, and 2000 kWp. Annual PV production ranges from approximately 739 MWh (500 kWp) to 2970 MWh (2000 kWp), and it is all fully self-consumed by the factory due to its high and continuous load. However, given the plant’s large annual electricity use, the PV systems offset 1.0–2.8% of total consumption. The avoided grid purchases correspond to 40–160 MWh/year of net energy savings, delivering positive Net Present Value (NPV) when electricity tariffs exceed EUR 0.15/kWh. The results confirm that zero feed-in PV deployment is technically feasible and economically attractive for industrial facilities facing high electricity prices, while also enhancing sustainability by reducing dependency on the public grid. Full article

Precision field measurements were conducted to evaluate the mechanism of organic basin mulching on water and thermal dynamics in arid date palm orchards in central Saudi Arabia. Partly mulched zones (20 m radius) and fully mulched basins were compared with adjacent bare soil using micrometeorological sensors and microlysimeters. In partly mulched areas, soil heat flux (G) decreased by 68.3% while sensible heat flux (H) increased up to 86.9% during late spring, indicating enhanced energy redistribution. Bare soil exhibited slightly negative latent heat flux (λE) in early spring, reflecting vapor adsorption, whereas fully mulched basins substantially reduced evaporation, with Water Conservation Efficiency Index (WCEĪ) values of 0.33 in spring and 0.27 in summer, corresponding to 33% and 27% water savings, respectively. Root-zone thermal moderation, quantified by the Root-Zone Thermal Moderation Index (RTMI), confirmed effective buffering of subsurface temperatures by 6–7 °C across 2–10 cm depths, despite slightly elevated surface temperatures. These results demonstrate that basin mulching stabilizes soil moisture, moderates diurnal thermal fluctuations, and optimizes soil–atmosphere energy partitioning under arid conditions. By integrating direct lysimeter measurements with continuous energy flux observations and index-based analysis, this study provides novel, field-based insights into the dual role of organic mulching in enhancing water conservation and thermal regulation in arid date palm orchards. Full article

Nowadays, the building sector is responsible for 30% of the global final energy demand and 37% of global energy and process emissions. In this context, industrial buildings account for 33% of global final energy consumption, representing one of the most energy-intensive sectors. The challenging European goal of achieving a carbon-free economy by 2050 is not reachable without intervening on the existing building stock. This research study aims to propose several retrofitting measures implemented in existing Italian industrial facilities to ameliorate energy and environmental performance, as well as to guarantee better indoor thermal conditions for workers. These interventions deal with both external envelope interventions and conditioning system improvements, along with their possible combination, to identify the most cost-effective solutions. A life cycle cost (LCC) analysis is performed to assess and compare the different redevelopment measures to identify the advisable ones considering the initial investment expenditure and operational and maintenance costs during a life span of 20 years. To define the cost-effective solution, different synthetic indexes are considered in the analysis. A sensitivity analysis is conducted on the discount rate and the operational life of the building (20 years). Redevelopment measures concerning conditioning systems seem to be the most advantageous ones in terms of operational energy savings and payback period evaluation if renewables are installed. The latter possibly makes industrial buildings carbon-neutral. The interventions on the external envelope allow buildings to meet the current Italian regulations in terms of thermodynamic properties, even if they affect the operational cost to a lesser extent. Full article

Promoting sustainability in the building sector requires greater attention to household energy-saving behavior alongside technical efficiency measures. This exploratory longitudinal study investigates how an educational intervention influences residents’ environmental awareness, knowledge, energy-saving behaviors, and motivation, while examining psychological barriers to behavioral change—specifically procrastination and comfort prioritization. The study was conducted in two residential building types in Sétif, Algeria (high-end and mid-range housing), using a pre–post questionnaire design to assess changes before and after the intervention. Findings indicate measurable improvements across all examined determinants: mean awareness scores increased from 2.10 to 3.75, knowledge from 1.75 to 2.66, reported energy-saving behavior from 2.53 to 3.36, and motivation from 2.27 to 3.83 following the educational phase. Nonlinear regression analysis further suggests that procrastination and comfort prioritization explain 40.8% of the variance in reported energy-saving behavior, underscoring the importance of psychological determinants in residential energy use. Overall, the results point to the potential of educational and behavioral strategies to complement technical measures in promoting household energy saving. Given the exploratory and context-specific design, this study offers initial empirical insights and establishes a foundation for future research involving larger and more representative samples, a broader range of building types, and diverse sociocultural settings. Full article

Water systems experience increasing sustainability challenges from climate variability, aging infrastructure, and energy and chemical intensity demands, but AI has typically been assessed against prediction accuracy rather than demonstrated operational success. This PRISMA 2020 systematic review analyzed the role of AI solutions on sustainability in distribution, treatment, and basin management. The database search identified 920 records; after deduplication (n = 185), screening was conducted on n = 735 titles/abstracts and examination of the full text for n = 85, providing a total of n = 41 included peer-reviewed studies for qualitative synthesis and n = 38 for quantitative/bibliometric synthesis with the additional analysis of seven grey-literature sources. Evidence mapping reveals high growth post-2020, and distribution and wastewater operations are dominated by a few companies. The most deployable evidence is found with monitoring, anomaly/leak detection, and short-term forecasting, while optimization and reinforcement-learning control are primarily simulation validated with limited field applications. While accuracy metrics are often reported, transformation into water saved, kWh/m³, chemicals, compliance/reliability/resilience/equity measures are inconsistently and less frequently operationalized. In general, AI is most believable when it is part of analysis-ready workflows, bounded decision support, and measurement-and-verification. Full article

Buildings account for nearly 40% of global energy use and 36% of CO₂ emissions, positioning Net-Zero Energy Buildings (NZEBs) as vital for climate mitigation. However, large-scale adoption remains limited by technical, economic, and policy barriers. This study systematically reviews 1285 peer-reviewed articles (2015–2025) from Scopus and Web of Science, following PRISMA guidelines and thematic analysis to assess renewable energy integration and efficiency strategies. Results indicate that 70% of studies highlight emissions reduction and cost savings as key NZEB benefits, while 60% cite high storage costs and 45% report grid integration challenges. Only 30% of studies address policy dependency, revealing a research gap. Effective measures include passive solar design (up to 25% heating load reduction), high-performance envelopes (15–40% energy savings), and smart energy management (10–20% efficiency gains). Persistent obstacles involve high upfront costs, renewable variability, and rapid technological obsolescence. Achieving NZEB viability requires integrating energy-efficient design, affordable renewables, advanced storage, and coherent policy frameworks to accelerate the transition toward a sustainable, NZEB-built environment. Full article