Search Results (263)

Hybrid-electric powertrains offer a solution to significantly reduce aircraft emissions in flight. This study presents a method that couples the generative design of hybrid-electric architectures with reinforcement learning for the optimization of their control parameters. The application proposed is the retrofitting of an ATR-72 with the objective of identifying an optimal green architecture. The results show that a promising candidate is a dual fuel powertrain combining a gas turbine and fuel cells. Compared with a conventional architecture, this concept reduces ${\mathrm{CO}}_2$ and ${\mathrm{NO}}_x$ emissions by up to 74% and 86%, respectively, incurring a payload mass penalty of only 24%. Full article

Building Information Modelling (BIM) and Life Cycle Assessment (LCA) are increasingly integrated to support environmental assessment in the built environment. However, applications to existing and heritage buildings remain fragmented, and the contribution of Heritage Building Information Modelling (HBIM) to Life Cycle Assessment is still poorly defined. This study presents a systematic review of 41 peer-reviewed publications retrieved from Scopus and reported according to the PRISMA 2020 guidelines, combining bibliometric, thematic and workflow-oriented analyses. Studies were selected according to predefined eligibility criteria based on relevance to HBIM-LCA integration. Three main BIM–LCA workflow typologies are identified: manual/export-based, plug-in-based and IFC-enabled interoperability approaches. While these workflows have progressively improved automation and data exchange, their application to existing and heritage buildings remains largely scenario-driven and focused on comparing refurbishment, retrofit, adaptive reuse and reconstruction alternatives. The review shows that HBIM distinctive contribution does not lie in environmental calculation methods, but in its ability to structure knowledge related to existing assets, including conservation state, intervention history, information provenance, uncertainty and life cycle transformations. However, current HBIM information structures remain only partially aligned with LCA requirements, particularly regarding service life, end-of-life scenarios and knowledge management. Semantic technologies emerge as a promising pathway towards knowledge-level interoperability. Limitations are related to the heterogeneity of the reviewed studies and the predominance of qualitative evidence. Digital-Green Heritage Workflows integrating HBIM, LCA and semantic technologies enable more transparent, life cycle-oriented and sustainable heritage conservation. Full article

Community-scale sustainable built-environment practices are increasingly important for linking urban sustainability policy with everyday spatial transformation, yet the evidence base remains fragmented across nature-based solutions, housing retrofit, settlement upgrading, public-space transformation, digital mapping, circular infrastructure, and governance-oriented planning. This scoping review, reported in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews (PRISMA-ScR), maps and synthesizes peer-reviewed evidence on community-scale sustainable built-environment practices, with publication years from 2015 to 2026 and indexed by the final search date of 13 June 2026. Searches were conducted in Scopus and the Web of Science Core Collection, yielding 3506 records. After duplicate removal, title-and-abstract screening, and full-text eligibility assessment, 130 studies were included for Spatial–Social–Governance (SSG) coding and thematic synthesis. This review identified eight thematic clusters, led by nature-based and green–blue infrastructure practices, followed by housing, retrofit, and settlement upgrading; neighborhood sustainability assessment and planning; public-space transformation and placemaking; digital tools and mapping; circular neighborhood infrastructures; mobility-related practices; and heritage-led regeneration. The largest concentration of evidence was found in nature-based and green–blue infrastructure practices, followed by housing, retrofit, and settlement upgrading; smaller clusters extended the field towards neighborhood assessment, public-space transformation, digital evidence systems, circular infrastructures, mobility, and heritage-led regeneration. As a review-derived synthesis output, the Spatial–Social–Governance Mechanism Framework does not introduce spatial, social, and governance as new analytical dimensions. Instead, it operationalizes these established concerns as a common comparison structure for heterogeneous community-scale built-environment practices, linking spatial intervention, social embedding, and governance enablement. The framework is neither a general theory nor an effectiveness model; its contribution is an integrative and review-specific analytical instrument. Full article

Nature-based solutions (NBSs) are central to urban climate-neutrality strategies, but their implementation still lags behind policy ambition. One reason is that most NBS benefits are public goods and rarely generate direct revenue, so we know far less about the institutional and financial conditions needed to deliver them than about their ecological performance. This paper develops a business model framework linking NBS interventions to financing and governance configurations, applying established NBS typologies and the Pestoff Triangle of state, market, and community provision to thirteen interventions across eleven sites in the Railway District of Thessaloniki, Greece. The interventions are organised into five business model categories: public space greening, private space upgrades, public–private hybrids, building retrofits, and renewable energy. Their financing logic is shaped less by intervention type than by ownership structure and stakeholder configuration. To address this gap, we followed category-specific blended finance strategies combining grants, private investment, regulatory incentives, and community resources, underpinned by stewardship-oriented governance. The findings suggest that scaling NBSs depends less on technical readiness than on institutional capacity to match financing and governance to local ownership and stakeholder contexts, offering a pathway from climate-neutrality strategy to implementable urban regeneration. Full article

Educational buildings account for approximately 17% of the building sector’s energy consumption, making them critical for zero-emission building (ZEB) strategies. With students spending over 50% of their time indoors, life-cycle carbon assessments and targeted retrofitting are essential for realizing UN sustainability goals on campuses. This study develops a comprehensive life-cycle carbon assessment framework using a Calibrated Building Energy Simulation to simultaneously evaluate embodied and operational carbon emissions in campus facilities. This research evaluates two distinct university buildings for analysis: a historical 1970 educational building in Cosenza, Italy (Mediterranean climate) and a modern 2009 building in Ankara, Türkiye (semi-arid/continental climate). To minimize the total carbon footprint, seven distinct retrofitting scenarios are systematically simulated and compared: adding photovoltaic (PV) panels, integrating solar films on windows, applying internal and external insulations, implementing green wall applications, applying psychological-adaptive HVAC control and decreasing the heating set-point temperature. Results indicate that psychological-adaptive HVAC control is the most effective, achieving approximately 19.3% operational carbon savings across both cases with a low embodied carbon penalty. Conversely, the green wall application was the least effective, with a carbon payback period of 53.55 years. Ultimately, this study provides actionable engineering pathways for transforming campus buildings into net-zero emission educational facilities. Full article

In response to issues such as disordered airflow distribution and prominent local hotspots in campus non-standard data centers, this study took a non-standard raised-floor air-supply data center at a university in Hangzhou as the research object, and used a combination of on-site measurements and computational fluid dynamics (CFD) numerical simulation to investigate the optimization of the thermal environment. The temperature and air velocity of the data center were measured using a handheld hot-wire anemometer, and a standard k-ε turbulence model was established on the 6SigmaDC platform (now Cadence Reality DC Design Pro, version 2024.1). Model accuracy was confirmed through grid independence verification with three mesh levels and statistical error metrics (MAE, MBE, RMSE) across multiple measurement zones. The results show that the mean absolute error of temperature does not exceed 0.9 °C in all zones and the mean absolute error of air velocity does not exceed 0.20 m/s, indicating that the model effectively reproduces the airflow distribution and thermal environment of the data center. On this basis, to address the uneven airflow distribution in the underfloor plenum, an optimization strategy was proposed that involved the installation of composite baffles and the coordinated adjustment of variable floor tile openings. Eight representative simulation scenarios were designed, with the coefficient of variation and air supply uniformity index as evaluation indicators. Results indicate that the combined effect of perforated baffles and variable floor tile openings is the optimal strategy, reducing the range of net airflow among air supply outlets from 0.100 to 0.077 m³/s, decreasing the coefficient of variation from 12.8% to 10.8%, and increasing the air supply uniformity index by 10.7%. Whole-room thermal environment verification shows that the optimal scheme reduces the supply heat index (SHI) from 0.42 to 0.35, with an estimated PUE reduction of about 0.03, achieving both airflow uniformity improvement and energy-saving benefits. By improving the cooling efficiency and reducing the PUE, this retrofit strategy contributes to the sustainable operation of small-to-medium-sized campus data centers, supporting energy efficiency and carbon footprint reduction goals under green campus and low-carbon initiatives. Full article

Simulation-dependent energy analysis has long dominated building retrofit research, yet this paradigm presents substantial barriers for non-expert building owners who lack technical software proficiency and detailed building documentation-a challenge compounded by the “curse of dimensionality” when multivariate analysis requires thousands of samples beyond available empirical records. Leveraging retrofit data accumulated through Korea’s Green Remodeling programs since 2017, this study proposes a Copula-Genetic Algorithm (Copula-GA) integrated framework that enables rational retrofit decision-making with minimal user inputs (construction year, floor area, structural type). From 178 documented retrofit cases, Gaussian copula-based multivariate sampling generated 10,000 synthetic records while preserving inter-variable dependency structures. Building physics constraints addressing vintage-thermal performance and capacity-efficiency relationships filtered implausible combinations, yielding 9898 valid cases with correlation matrix fidelity confirmed by a Frobenius norm deviation of 0.043. Evolutionary clustering employing a composite fitness function of Silhouette coefficient (0.68) and Davies-Bouldin Index (0.52) identified K = 16 as the optimal partition, categorizing outcomes into four reference model archetypes: Lightweight Structure (Type A, 27.0% reduction, 15.7-year payback), Masonry Structure (Type B, 29.0%, 14.8 years), RC Structure (Type C, 30.7%, 13.4 years), and Mixed Structure (Type D, 30.9%, 13.1 years). The proposed Copula-GA framework bridges the gap between advanced energy optimization methodologies and practical accessibility for non-expert building owners. By transforming limited empirical samples into reliable reference models, this research supports building-sector decarbonization. Using three minimal inputs, a building can be matched to one of the 16 standard models to obtain its expected saving rate, payback period, and recommended measures without detailed simulation. Full article

Under China’s “carbon peaking before 2030 and carbon neutrality before 2060” targets, the low-carbon transformation of the ironmaking stage—which contributes approximately 70% of the CO₂ emitted per ton of steel in the dominant blast furnace–basic oxygen furnace (BF–BOF) route—is decisive for decarbonizing the steel industry. In contrast to earlier reviews that describe individual technologies in isolation, this review provides a structured, cross-technology synthesis: the main routes are classified into short-/medium-term low-carbon blast furnace technologies (hydrogen-rich carbon-recycling oxygen blast furnace, hydrogen-rich injection, biomass char injection and ultimate energy-efficiency measures) and medium-/long-term non-blast furnace technologies (hydrogen-based shaft furnace direct reduction, smelting reduction, rotary hearth furnace, fluidized-bed reduction and electric smelting reduction) and are then compared on a common set of quantitative indicators—CO₂ mitigation, specific energy and hydrogen demand, technology readiness level (TRL) and relative cost. On this basis, emerging hydrogen-based flash ironmaking, developed from the interdisciplinary integration of “iron and steel–non-ferrous metallurgy–hydrogen metallurgy–plasma”, is critically assessed, with a clear separation between laboratory/pilot feasibility and industrial readiness. We conclude that low-carbon blast furnace technologies, owing to low retrofit cost and high maturity, will dominate near-term mitigation, whereas hydrogen-based shaft furnaces and, in the longer term, hydrogen-based flash ironmaking define the pathway toward near-zero-carbon ironmaking—conditional on the availability of green hydrogen and low-carbon electricity and on overcoming key engineering barriers. Full article

Green remodeling projects for public buildings in South Korea aim to improve the energy performance of aging facilities, with a policy target of achieving at least 30% energy savings. Because the 30% saving rate functions as a key policy benchmark, it is necessary to identify why some projects achieve higher savings while others remain below the target. This requires a comparative analysis of energy-saving levels in relation to baseline energy-use composition and retrofit measure applications. This study analyzes the 1954 preliminary investigation and ECO2-OD-based assessment cases of public building green remodeling projects to examine energy-saving levels, baseline energy-use composition, end-use contributions, and retrofit measure applications. Pre- and post-retrofit primary energy demand for heating, cooling, domestic hot water, and lighting were used to calculate energy-saving rates. Based on the 30% policy target, the cases were classified into Low-saving, Target-achieving, High-saving, and Very-high-saving levels. The average energy-saving rate was 36.02%, but 39.61% of cases remained below the 30% target. Higher-saving groups showed greater baseline heating energy shares, increasing from 53.38% in the Low-saving group to 66.18% in the Very-high-saving group, suggesting an association between pre-retrofit energy-use structure and predicted retrofit potential under the ECO2-OD assessment framework. Heating was also the dominant contributor to total savings, with its contribution rising from 17.07 to 44.94 percentage points. Higher-saving cases tended to involve more comprehensive retrofit packages combining envelope, system, and lighting improvements. These findings suggest that energy-saving targets and retrofit strategies should consider baseline end-use energy composition and establish differentiated saving targets according to building characteristics, rather than relying only on uniform policy targets and average project performance. Full article

Urban Building Energy Modelling (UBEM) is increasingly recognised as a key tool for bridging building-scale analysis and city-level planning, supporting the decarbonisation of urban areas. It enables the assessment of building performance and the exploration of retrofit strategies, policy scenarios, and renewable integration. Over the past decade, UBEM has continuously evolved, encompassing physics-based, data-driven, and hybrid approaches, often supported by archetype generation and GIS workflows. Recent research also integrates microclimate, mobility, and green infrastructure. While this enriches analysis outcomes, it also leads to fragmentation, limiting tools’ comparability, transparency, and practical use by policymakers. This perspective paper provides a critical interpretation of the recent evolution in UBEM and proposes a goal-oriented classification of modelling approaches based on their final objectives rather than on calculation methodology. The paper also identifies three key gaps: the lack of scalable and consistent data frameworks, the absence of a shared terminology, and the need for criteria to assess whether models are “fit for purpose.” Addressing these issues through improved data infrastructures, conceptual clarity, and reliability assessment can support convergence without limiting innovation, fostering more robust and decision-relevant UBEM applications to support the energy transition. Full article

With the intensifying global climate change and the full implementation of China’s “dual-carbon” strategy, the green and low-carbon transition in rural areas has become a core issue in urban and rural construction. As China’s most economically developed and highly urbanized region, the Yangtze River Delta (YRD) holds typical demonstrative significance in the research and practice of green and low-carbon rural construction. This study retrieves 4166 core documents from the China National Knowledge Infrastructure (CNKI), Web of Science (WoS), and Scopus published between 1997 and 2025 to perform multi-database bibliometric analysis and knowledge mapping analysis. CiteSpace and VOSviewer are employed to conduct a comparative analysis of domestic and international literature and to delineate the knowledge evolutionary trends, core research hotspots, and research trajectories in this field. The findings reveal that the research on green and low-carbon rural construction in the YRD has experienced three stages. The first stage involves the introduction of foundational low-carbon concepts, the second stage centers around green transition and policy response, and the third stage is driven by the national rural revitalization and “dual-carbon” strategies. Moreover, five principal research directions have been determined, including spatial planning based on “low-carbon control units”, excavation of green wisdom from traditional villages, discussion of passive green strategies, retrofitting of existing rural residences and integration of low-carbon technologies, and precision rural construction based on industry–space synergy. Consequently, by constructing a dual-thread evolutionary framework integrating the natural ecosystem with the social system, this study systematically extracts the theoretical contributions, paradigm characteristics, and transferable empirical models from the research on green and low-carbon rural construction in the YRD, and proposes a future agenda to facilitate the shift in research paradigm from “problem solving” to “forward planning”. Ultimately, this study aims to offer a demonstrative “YRD solution” for the sustainable development of rural areas in China and beyond. Full article

Historic residential buildings in Lingnan are affected by hot–humid and disaster-prone weather conditions, including high temperature, high humidity, intense solar radiation, monsoon winds, and typhoon-related climate stress, which challenge indoor thermal comfort, daylighting, natural ventilation, and adaptive reuse. Taking Jingzu Jiashu, a historic Chaoshan residence associated with overseas remittance culture, as a case study, this study develops a simulation workflow for climate-adaptive green retrofit. Digital documentation, architectural survey, material investigation, and climate data were integrated to establish a baseline model. PMV, DA300, and ACH/ACR were used to evaluate thermal comfort, daylighting, and natural ventilation. The baseline results show summer overheating, insufficient daylighting in deep rooms, and inadequate ventilation in representative rooms. Comfortable hours accounted for only 7.29–7.78%, thermally uncomfortable hours reached 42.84–51.53%, and the maximum PMV reached 4.65 in the rear hall and 3.54–3.65 in representative rooms. The effective daylight areas of the front and rear rooms were approximately 40% and 31%, while baseline ACH values ranged from 1.06 to 1.89 h⁻¹. An integrated retrofit strategy was proposed, including functional reorganization, envelope optimization, opening adjustment, ventilation-path organization, and courtyard/transitional-space improvement. After retrofit, comfortable hours increased to 32.00–42.45%, thermally uncomfortable hours decreased to 17.25–21.28%, maximum PMV values decreased to 1.82–1.86, daylight areas increased to 81% and 74%, and ACH values rose to 2.97–4.49 h⁻¹. The results indicate that building performance simulation can provide quantitative support for climate-adaptive green retrofit of historic Chaoshan residences in Lingnan, offering a methodological reference for healthier, lower-carbon, and more resilient reuse of similar historic dwellings. Full article

Urban combined sewer systems are increasingly challenged by climate-intensified rainfall, combined sewer overflows, and receiving-water degradation. This study presents a retrospective evaluation of a hybrid green-gray retrofit program implemented in the Zhenjiang Sponge City pilot watershed, China, where green stormwater infrastructure, drainage network upgrades, and a centralized deep tunnel system were integrated within a densely developed watershed constrained by limited space, low native-soil permeability, shallow groundwater, and aging infrastructure. System performance was evaluated using long-term operational observations, representative hydraulic and water-quality monitoring, municipal operational records, and supporting engineering analyses at both facility and watershed scales. The results demonstrated sustained hydraulic functionality after 7–10 years of operation, with approximately 90% of the monitored bioretention systems maintaining effective infiltration rates greater than 80 mm h⁻¹. Event-based monitoring indicated substantial reductions in runoff volume and pollutant loads, including TSS, COD, NH₃–N, and TP. Following implementation, annual combined sewer overflow occurrence at major outfalls decreased from 318 to 24 events, representing a 92.5% reduction. Supporting engineering analyses indicated that green stormwater infrastructure retrofits alone reduced overflow frequency by approximately 41.8% and overflow volume by approximately 61.1%, while integration with deep tunnels increased reductions to approximately 58.8% and 85.3%, respectively. Official receiving-water monitoring records further indicated that Class III or better water-quality conditions were maintained during approximately 74.7% of the monitored days between 2021 and 2026. These findings provide long-term watershed-scale evidence that hybrid green-gray retrofit strategies can integrate green stormwater infrastructure with centralized overflow regulation to achieve sustained overflow reduction and receiving-water improvement in highly constrained urban watersheds. Full article

Industrial process systems must reduce energy use and carbon emissions while maintaining productivity under binding constraints. Energy-use rights trading (EURT), also referred to as energy-consuming rights trading, energy quota trading, or energy-consumption permit trading, converts administrative energy-consumption control into tradable entitlements. This narrative and integrative review uses a transparent search-and-screening audit and reframes EURT primarily through the Chinese pilot experience, while using international energy-efficiency certificate and obligation schemes as comparative context. The review examines how quota scarcity, quota prices, monitoring, reporting and verification, trading liquidity and policy coordination may influence process-level energy management, production scheduling, heat integration, waste-heat recovery, equipment renewal, fuel substitution, electrification, digital monitoring and low-carbon retrofit decisions. It compares EURT with carbon-emissions trading, pollution-permit trading, white-certificate or energy-efficiency-obligation schemes, water-rights trading and renewable-energy certificates. Evidence suggests that EURT can support pollution reduction, carbon mitigation, and green productivity improvement when quota scarcity is binding, markets are liquid, monitoring is reliable, and policy coordination is credible, but findings remain heterogeneous and vulnerable to contamination from overlapping policies. A stylized process-system illustration shows how quota prices can alter the ranking of retrofit investments. Future research should integrate transaction records, equipment-level energy data, process simulation and multi-policy identification strategies. Full article

Green retrofit of existing residential communities (GRERC) is critical for upgrading aging building stocks, but their true value extends far beyond physical improvements. A successful retrofit must simultaneously deliver economic, social, and ecological benefits. However, in practice, the value realization is often constrained by a complex network of interdependent factors. This study maps these underlying structures. We first extracted a preliminary set of variables from existing literature and case studies, validating them through survey data. By applying Decision-Making Trial and Evaluation Laboratory (DEMATEL) and Interpretive Structural Modeling (ISM) techniques, subsequently, the reciprocal influences and the multi-level structural organization within the identified system were mapped. Our analysis isolates three foundational drivers: government evaluation standards, policy incentives, and ecological awareness. Crucially, these elements do more than exert direct pressure—they dictate the systemic transmission pathways that enable value realization. To bridge the gap between policy and practice, regulators must prioritize making evaluation standards practically actionable. Furthermore, scaling GRERC effectively will require redesigning incentive mechanisms to attract broader social participation and dramatically improving public access to retrofit information. Full article