Search Results (545)

Though the European Commission has repeatedly stated that the necessary energy transition in Europe should leave “no one behind”, this paper describes a building refurbishment case that has entailed economic hardships for the low-income families involved. The project is located in the area of P. D. Orcasitas in southern Madrid, led by a grassroots neighbours’ movement, comprising one hundred and seven housing blocks, containing more than 2000 dwellings. The main source of funding for the operation consists of subsidies granted by the Madrid City Council; however, Spanish legislation requires the state Agency of Tax Administration to classify these subsidies as capital gains derived from lucrative transfers. Based on the tax data of vulnerable beneficiaries, the conclusion is that the recipients have ended up returning part of the subsidies to the State through their Income Tax Return. In addition, the Spanish Social Security Institute requires the return of social benefits associated with non-contributory retirement pensions and the Minimum Living Income. Apart from tax accounting, regulations are revised to draw conclusions. Unlike most actuations of this kind, in this case the negative effects are obvious. Although intended to alleviate fuel poverty, the initiative has exacerbated vulnerability due to the impact of the imposed penalties on household income. In conclusion, unless preventive measures are implemented, the mandatory refurbishment of inefficient buildings may place an undue burden on vulnerable low-income occupants and hinder the effective implementation of energy-efficiency regulations. Full article

The tragic fires at the Grenfell Tower (London, UK) in 2017 and the building in the Campanar neighbourhood (Valencia, Spain) in 2024, among other fires, occurring in existing high-rise residential buildings with combustible façades, have prompted a review on regulations and statutory procedures, as well as the development of new risk assessment methods, research reports, and expert studies in order to enhance fire safety in such buildings. Within this context, this article is aimed at providing a compilation, in the form of a preliminary state-of-the-art review, of various fire safety measures that can be adopted in these types of buildings, and to contrast the main measures identified with the requirements set out in Spanish national regulations. Full article

Asbestos-containing materials (ACMs) are among the most common types of hazardous building materials. Usually, ACMs are identified by laboratory methods, which can slow down and complicate the processes of demolition and refurbishment of old buildings. The hypothesis applied in this study is that ACMs, both in friable and non-friable forms, can be reliably identified in situ using a handheld Raman spectrometer (HHRS). A HHRS equipped with two temperature-controlled diode lasers (785 nm and 852 nm) was used. Two groups of ACMs were examined: one, consisting of ACMs with a known type of asbestos, previously determined by standardised tests used for the HHRS method’s validation, and the second, consisting of presumed ACMs, where HHRS was used for the identification of asbestos. Additional testing according to ISO 22262-1 was applied. The impact of several factors on the asbestos identification was evaluated. The results confirm that the identification by HHRS of all main types of asbestos minerals is possible with a certain level of probability, regardless of whether the fibres are in an unbound form (fabrics, ropes, wools) or bound within cementitious or polymer composites. Some processing (scaling, smoothing) of the reference spectra should be applied to increase the percentage of asbestos minerals’ identification. In conclusion, it has been proven that the majority of ACM in buildings may be identified in situ by HHRS in a rapid manner, thus accelerating the pre-demolition/pre-renovation audit (PDA/PRA), avoiding risks to demolition/refurbishment workers’ health due to asbestos unawareness, as well as preventing the contamination of other CDW and environmental pollution. Full article

Hydropower refurbishment is increasingly recognized as a key strategy for maintaining renewable electricity generation and minimizing the environmental and social impacts of developing new infrastructure. With much of the global hydropower fleet approaching or exceeding its original design life, refurbishment decisions must strike complex trade-offs between technical performance, environmental impacts, economic viability, and social acceptability. This review provides a comprehensive summary of the scientific and policy literature on sustainable hydropower refurbishment, with a particular focus on the integration of life cycle assessment (LCA) and multi-criteria decision analysis (MCDA) from a circular economy perspective. The study systematically reviews the latest results in the fields of environmental LCA, life cycle costing (LCC), social LCA (S-LCA), and integrated life cycle sustainability assessment (LCSA), highlighting their application in the refurbishment and modernization of hydropower plants. The results show that construction-related impacts, particularly those associated with concrete and steel, dominate the environmental load over the life cycle, making refurbishment and component recycling highly effective strategies for reducing embodied emissions. The integration of LCA and MCDA allows for the transparent prioritization of refurbishment alternatives by explicitly considering stakeholder preferences and trade-offs between environmental, economic, social, and technical criteria. Overall, the results support the use of integrated, multi-criteria life cycle frameworks as reliable decision-making tools for managing sustainable hydropower refurbishment and long-term energy system resilience. Full article

Movable guardrail systems are increasingly used in work zones, reversible lanes, and temporary traffic operations; however, evidence on their crashworthiness, material performance, and operational reliability remains dispersed across multiple design typologies and regulatory frameworks. This PRISMA-compliant systematic review synthesizes 78 studies involving full-scale crash tests, validated finite-element simulations, field performance evaluations, and compliance evaluations under MASH, EN 1317, NCHRP 350, and AS/NZS 3845.1. The findings indicate that modular rigid barriers reliably achieve TL-3/TL-4 performance when joint alignment and foundation conditions are properly controlled; semi-rigid steel systems provide a practical balance between containment capacity and redeployability, but remain sensitive to post spacing and connector detailing; and flexible polymer systems are best suited for short-duration, low-speed applications. Material-focused research highlights the advantages of UHPC section refinement, high-strength steels, and hybrid FRP–metal configurations in enhancing energy absorption without exceeding occupant-risk thresholds. Across studies, connection integrity consistently emerges as the dominant factor governing redirection stability and working-width performance. Field evaluations confirm satisfactory operational performance in constrained environments, while life-cycle assessments identify refurbishment intervals and mass-related logistics as major cost contributors. This review provides an integrated, evidence-based synthesis and a structured engineering foundation for advancing next-generation movable barrier designs, testing protocols, and deployment strategies. Full article

Hydropower plants remain strategic assets for grid stability and decarbonization, with hydraulic turbines governing conversion efficiency, reliability, and environmental performance. This systematic review synthesizes recent methodologies for evaluating and optimizing turbine operation and maintenance to enhance efficiency, reduce impacts, and extend service life. Following a PRISMA-aligned protocol, studies published between 2020 and 2025 were screened across Web of Science and Scopus, using predefined eligibility criteria and a two-stage selection process. The resulting evidence was thematically analyzed across three domains: lifecycle and circular-economy-oriented refurbishment strategies; digitalization and predictive maintenance approaches; and environmentally optimized operating regimes. Of the 115 screened records, 37 met the inclusion criteria. Findings indicate that predictive monitoring, data-driven maintenance, and turbine selection tailored to local hydrology can significantly improve energy performance while reducing operation and maintenance costs. The literature also highlights the importance of ecological flow compliance and reduced aquatic impacts. Complementary case studies from Nepal, Switzerland, Germany, Portugal, and Romania illustrate regional challenges and modernization pathways. Overall, the review underscores the need for integrated, multi-objective turbine management that aligns techno-economic, lifecycle, and ecological considerations to support hydropower competitiveness within the energy transition. Full article

Residential buildings in Erbil City are increasingly facing challenges due to climatic extremes, rapid urbanization, and inadequate insulation practices. This study investigates the effects of insulation material type and placement on the thermal performance of external walls in both newly constructed and refurbished houses under the hot semiarid climate (BSh). Using integrated environmental solutions virtual environment (IES-VE) simulations, various wall systems—concrete, brick, and lightweight block—were assessed with different insulation types (expanded polystyrene (EPS), extruded polystyrene (XPS), rock wool (RW), and mineral wool (MW)) applied either internally or externally. Field surveys combined with numerical simulations demonstrated that external insulation significantly enhances thermal mass without diminishing insulation effectiveness, leading to greater energy savings and improved indoor comfort. Among all configurations, externally applied XPS on concrete and lightweight block walls achieved the highest resistance values (R-values) and the greatest reductions in heating and cooling loads. The results indicate that prioritizing the placement of external insulation can support the development of more energy-efficient and climate-responsive housing policies in Erbil. This research offers evidence-based recommendations for optimizing building envelope design in similar climatic contexts. Full article

Extensive glazing is a common feature of modern buildings, intended to maximize daylight and strengthen visual connections with the outdoors. While this strategy can enhance energy performance, its effectiveness strongly depends on climate, orientation, and seasonal variations, and it often introduces challenges related to visual comfort, particularly glare. This paper proposes a refurbishment methodology that systematically integrates the view out, often neglected in current practice, into the decision-making framework, focusing on its relationship with daylight. The methodology follows a stepwise process encompassing the identification of discomfort conditions, evaluation of intervention feasibility, and design of targeted refurbishment strategies. Its main innovation lies in integrating and verifying a balance between view quality and daylight within a unified analytical framework. Validation through a university building in València confirmed that optimizing these parameters represents a significant design challenge, as enhancing one may compromise the other. The analysis also revealed limitations of current standards, such as EN 17037, whose static approach fails to capture the dynamic interactions among daylight, shading operation, and user perception. Furthermore, the proposed methodology introduces a scalable level of analytical granularity, enabling the assessment depth to be adapted to economic resources and time constraints, thereby supporting informed and sustainable decisions in building refurbishment. Full article

Despite the rapid expansion of green roof installations in the United States, little empirical evidence exists regarding their long-term persistence or post-installation management. This study evaluates post-installation outcomes for 46 green roofs across ten southeastern U.S. states using a structured survey and publicly available records. Roofs were classified by status (managed, abandoned, removed, mid-refurbishment, or unknown) and management intensity. Associations with ownership change, building type, and Leadership in Energy and Environmental Design (LEED) certification status were examined using Fisher’s Exact Tests and logistic regression. Only 47.8% of roofs were actively managed at the time of data collection, while 45.7% had been abandoned or removed. Ownership change was significantly associated with roof failure (Fisher’s Exact Test, p = 0.001), with no managed roofs experiencing post-installation ownership turnover. In contrast, LEED certification status was not associated with either roof persistence or management intensity. These findings indicate that institutional continuity and sustained management play a critical role in determining long-term green roof outcomes and suggest that installation-based incentives may overestimate the number of functioning green roofs. By shifting evaluation beyond ecological performance metrics alone, this study highlights governance and institutional stability as central factors shaping roof longevity. Full article

This paper presents an analysis of user preferences regarding the use and design of toilets in densely populated buildings. Toilets are a necessary utility in all buildings, but little is known about users’ preferences, which often leaves building designers relying on the simple application of design codes or manufacturers’ instructions. The opportunity for this research was offered by the renovation of the sanitary facilities taking place in a large university building at the Iuav University of Venice. When the research was carried out, only half of the toilets of the building had been renovated, offering a unique opportunity to compare the preferences of users between the refurbished and the old toilets. Students enrolled in the undergraduate architecture program hosted in the building were surveyed with a questionnaire to monitor their preferences for using the toilets, comparing the old and new layouts and technical characteristics of the bathrooms. Simultaneously, on-site observations were conducted to measure the occupation of toilet blocks and compare the performance of the new versus the old layout. The results offer novel and detailed information on the use of bathrooms by a homogeneous group of users and their preferences concerning the design features of lavatory spaces, highlighting user-centered design priorities. The results contradict some commonplaces, for instance about the longer time spent in public restrooms by females. Also, results highlight the limited usage of urinals by males but evidence how the minority of males that do use them create an advantage for the whole male population. Full article

In an increasingly volatile global financial environment, strong institutions and sound governance are essential for safeguarding banking stability and mitigating systemic risks in emerging economies. Across the 11 emerging economies examined, weaknesses in institutional quality and inconsistencies in governance frameworks continue to elevate credit risk and undermine financial resilience. This study investigates the effects of institutional quality (IQ) and corporate governance (CGG) on bank stability, drawing on the Financial Stability and Risk Management (FSRM) theory, which highlights robust institutions, effective risk oversight, and sound governance as core determinants of financial system strength. Using dynamic panel data from 2011–2024, the study applies the generalized method of moments (GMM) approach to assess bank performance through non-performing loans (NPLs) and Z-Score as key dependent variables. The model incorporates IQ, CGG, bank-specific characteristics (bank assets, capital adequacy, cost-to-income ratio), and macroeconomic indicators (GDP, inflation, exchange rate, real interest rate) as explanatory factors, addressing endogeneity, unobserved heterogeneity, and persistence in banking outcomes. The results reveal strong persistence in NPLs (lag = 0.965, p < 0.01) and Z-Score (lag = 0.920, p < 0.01), indicating notable path dependence in bank performance. Institutional quality significantly enhances bank stability (Z-Score coefficient = 0.073, p = 0.040), while BA shows a negative but insignificant effect (coefficient = 0.005, p = 0.432), implying that rapid asset growth without prudent risk management may weaken resilience. CGG shows negative but insignificant effects, while macroeconomic factors also appear insignificant, indicating limited short-term impact. Countries with stronger institutions, such as South Korea, display lower NPLs and higher stability, whereas weaker institutional environments like Iran, Pakistan, and Bangladesh face higher credit risk and reduced stability. Overall, the study highlights IQ and prudent balance sheet management as key to stronger bank stability, urging policymakers to reinforce institutional frameworks, tighten regulatory discipline, and ensure controlled asset growth to reduce systemic vulnerabilities. Full article

Cavitation erosion is a critical problem for many engineering components, such as ship propellers, diesel engine exhaust valves, cylinder liners, pump impeller blades, hydraulic turbines, and bearings, which are exposed to high-velocity flowing fluids or to vibratory fluid motion. It represents a mechanical degradation of the surface caused by the continuous collapse of bubbles in the surrounding liquid, which seriously affects flow efficiency and component service life, increasing maintenance frequency and refurbishment costs. The intensity and evolution of the cavitation erosion phenomenon depend on the hydrodynamic conditions to which the component surface is exposed, the properties of the liquid, and the judicious selection of the most suitable material. This paper aims to modify the microstructure of a Ni-based superalloy by applying recrystallization annealing heat treatment in order to obtain surfaces resistant to cavitation erosion for components that handle fluids under local pressure fluctuations. Experimental tests are carried out using a vibratory apparatus with piezoceramic crystals operating at a frequency of 20 kHz and an amplitude of 50 µm. The cavitation erosion performance of the Ni-based superalloy INCONEL 625, heat treated by recrystallization annealing, are compared with that of austenitic stainless steel AISI 316L subjected to solution treatment. For both metallic alloys, based on mass loss measurements, the characteristic time-dependent curves of the mean cumulative erosion penetration depth, MDE(t), and the mean erosion rate, MDER(t), are determined. The comparison of these curves and of the parameters defined and recommended by the ASTM G32 standard demonstrates that, for the Inconel 625 superalloy, resistance to cavitation erosion increases by 77–81% compared to that of AISI 316L austenitic stainless steel. X-ray diffraction analyses (XRD) show that, in the microstructure of the Inconel 625 superalloy, in addition to austenite, MC-type carbides, M₂₃C₆ carbides, and intermetallic phases γ″ = Ni₃(Nb, Al, Ti) and δ = Ni₃(Nb, Mo) are also present. Full article

This conceptual article examines the shift of circular business models from policy-driven sustainability initiatives to commercially viable strategies in fast-moving product categories, with particular attention to repair, refurbishment, remanufacturing, and end-of-life recovery. Drawing on a structured narrative review and theoretical synthesis, it argues that circular models seldom scale within a single firm because slowing and closing resource loops require ecosystems that integrate product design, reverse logistics, and secondary markets. The paper develops an analytical framework that combines ecosystem strategy, complex adaptive systems, and common agency theory to explain how distributed complementarities, feedback dynamics, and multi-principal incentives jointly shape ecosystem trajectories. Reinforcing and balancing loops can accelerate, stabilise, or lock ecosystems into low-value routines, while incomplete contracts and divergent metrics may fragment effort and produce measurement traps. To address these coordination externalities, the framework introduces the super-principal as a meta-governance role that aligns principals through shared performance indicators, pooled funding rules, and investments in enabling infrastructures such as traceability. The framework offers implications for circular economy policy and ecosystem strategy aimed at sustaining higher-value circular loops. Full article

Rising global electricity demand and the expansion of distribution networks require a critical assessment of component-level greenhouse gas contributions. Distribution transformers, although indispensable, have significant life-cycle carbon impacts due to the use of materials, manufacturing, and in-service losses. This study conducts a life-cycle assessment of a single-phase, 75 kVA oil-immersed distribution transformer manufactured in Newfoundland, one of the provinces with the cleanest, hydro-dominated grids in Canada, and evaluates it over a 40-year lifespan. Using a cradle-to-use boundary, the analysis quantifies embodied emissions from raw material extraction, manufacturing, and transportation, alongside operational emissions derived from empirically measured no-load and load losses. All the data are collected directly during the manufacturing process, ensuring high analytical fidelity. The energy efficiency of the transformer is analyzed in MATLAB version R2023b using measured no-load and load losses to generate efficiency, load characteristics under various operating conditions. Under varying load factor scenarios and based on Newfoundland’s 2025 grid intensity of 18 g CO₂e/kWh, the lifetime operational emissions are estimated to range from 0.19 t CO₂e under no-load operation to 4.4 t CO₂e under full-load conditions. A linear regression-based decarbonization model using Microsoft Excel projects grid intensity to reach net-zero around 2037, two years beyond the provincial target, indicating that post-2037 transformer losses will remain energetically relevant but carbon-neutral. Sensitivity analysis reveals that temporary overloading can substantially elevate lifetime emissions, emphasizing the value of smart-grid-enabled load management and optimal transformer sizing. Comparative assessment with fossil fuel-intensive provinces across Canada demonstrates the dominant influence of grid generation mix on life-cycle emissions. Additionally, refurbishment scenarios indicate up to 50% reduction in cradle-to-gate emissions through material reuse and oil reclamation. The findings establish a scalable framework for integrating grid decarbonization trajectories, life-cycle carbon modelling, and circular-economy strategies into sustainable distribution network planning and transformer asset management. Full article

This study investigates the integration of eco-design strategies in the energy renovation of mid-20th century heritage buildings, using the Antonio Rueda Residential Complex in Valencia (Spain) as a representative case study. The research addresses the reconciliation between heritage conservation and contemporary environmental objectives by evaluating the building in terms of its construction and current performance. The multidisciplinary working methodology consists of creating a BIM-based workflow (Revit + Autodesk Insight) to generate an analytical energy model, quantify Operational Carbon, and evaluate the impact of lighting inside the homes to simulate the impacts of the intervention strategies. This is justified as existing buildings are energy intensive and heavily dependent on fossil fuels, largely due to insufficient façade insulation, obsolete window systems, and limited solar protection. Nine refurbishment scenarios were developed, ranging from reversible improvements to the building envelope to volumetric extensions inspired by the principles of eco-design and circularity. Comparative simulations suggest that specific improvements could significantly reduce energy demand while remaining compatible with the architectural identity of the complex. Full article