Search Results (476)

The growing need for sustainable and flexible automation solutions has led to the exploration of transforming traditional industrial robots into collaborative robots (cobots). This paper presents a framework for the conversion of conventional industrial robots into safe, intelligent, and sustainable cobots, leveraging advancements in artificial intelligence and computer vision and the principles of the circular economy. The proposed modular framework contains key components such as visual perception, cognitive adaptability, safe human–robot interactions, and reinforcement learning-based decision-making. Our methodology includes a comprehensive analysis of safety standards (e.g., ISO/TS 15066), robot typologies suitable for retrofitting, and sustainability strategies, including remanufacturing and lifecycle extension. A multi-phase implementation approach is laid out for a theoretical design to contribute to the development of cost-effective and environmentally responsible robotic systems, offering a scalable solution for extending the usability and social acceptance of legacy robotic platforms in collaborative settings. Full article

Efficient cooling and heat recovery systems are becoming increasingly critical in large-scale commercial and industrial facilities, especially with the rising demand for sustainable energy solutions. Traditional air-conditioning and refrigeration systems often dissipate significant amounts of waste heat, which remains underutilized. This study addresses the challenge of harnessing low-potential waste heat from such systems to support fifth-generation district heating and cooling (5GDHC) networks, particularly in moderate-temperate regions like Flanders, Belgium. To evaluate the technical and economic feasibility of waste heat recovery, a methodology is developed that integrates established performance metrics—such as the energy efficiency ratio (EER), power usage effectiveness (PUE), and specific cooling demand (kW/t)—with capital (CapEx) and operational expenditure (OpEx) assessments. Empirical correlations, including regression analysis based on manufacturer data and operational case studies, are used to estimate equipment sizing and system performance across three operational modes. The study includes detailed modeling of data centers, cold storage facilities, and large supermarkets, taking into account climatic conditions, load factors, and thermal capacities. Results indicate that average cooling loads typically reach 58% of peak demand, with seasonal coefficient of performance (SCOP) values ranging from 6.1 to a maximum of 10.3. Waste heat recovery potential varies significantly across building types, with conversion rates from 33% to 68%, averaging at 59%. In data centers using water-to-water heat pumps, energy production reaches 10.1 GWh/year in heat pump mode and 8.6 GWh/year in heat exchanger mode. Despite variations in system complexity and building characteristics, OpEx and CapEx values converge closely (within 2.5%), demonstrating a well-balanced configuration. Simulations also confirm that large buildings operating above a 55% capacity factor provide the most favorable conditions for integrating waste heat into 5GDHC systems. In conclusion, the proposed approach enables the scalable and efficient integration of low-grade waste heat into district energy networks. While climatic and technical constraints exist, especially concerning temperature thresholds and equipment design, the results show strong potential for energy savings up to 40% in well-optimized systems. This highlights the viability of retrofitting large-scale cooling systems for dual-purpose operation, offering both environmental and economic benefits. Full article

In the context of global decarbonization goals and increasing urban electricity demand, the green transformation of power industry buildings to enhance the utilization of renewable energy represents a significant contribution to sustainable social development. Rooftop photovoltaic (PV) systems can reduce unnecessary radiative heat gain and generate clean electricity to support this transition; however, they also alter the rooftop wind environment. Deploying rooftop PV systems requires well-planned design strategies to optimize renewable energy production while ensuring adequate natural ventilation, particularly for semi-outdoor main transformer rooms where ventilation and heat dissipation are crucial for safe substation operations. This concept was tested at a 220 kV substation in Guangzhou, China, using Computational Fluid Dynamics (CFD) and PVSYST to assess the impact of different rooftop PV systems on natural ventilation and power generation. The analysis showed that while the horizontal PV system achieved the highest energy output, it also resulted in a wind speed reduction of 13.2% or 11.8%. In contrast, the 10° symmetrical PV system offers the most balanced solution, with only a 0.6% decrease in ventilation performance but at the cost of a 13.87% reduction in PV output. The unilateral pitched PV system results in ventilation losses of less than 4%, and the power generation loss is also kept below 4%. However, this configuration may lead to increased wind loads. This approach can be developed into a practical design tool to further support the integration of PV systems in substation green retrofitting projects. Full article

China is the world’s leading producer of molybdenum–copper concentrates, an industry noted for its high energy demand and considerable environmental burdens. This study applies a cradle-to-gate life cycle assessment to the production of molybdenum–copper concentrate in the Lesser Khingan Mountains, utilizing the ReCiPe 2016 midpoint method coupled with Monte Carlo uncertainty analysis. The results indicate that human carcinogenic toxicity represents the greatest environmental risk, followed by marine and freshwater ecotoxicity. Contribution analysis reveals that the grinding stage is the dominant impact driver—particularly due to hexavalent chromium emissions—affecting carcinogenic risk, climate change potential, and fossil resource depletion. Scenario testing demonstrates that upgrading grinding technology, enhancing electricity efficiency, and substituting conventional energy with renewable sources can markedly mitigate these impacts. However, because of implementation barriers, such as high capital costs, retrofit downtime, and uncertainties in the supply chain, a pilot phase is necessary before deployment at full scale. Quantitatively, the production of one tonne of molybdenum–copper concentrate corresponds to 0.05 DALYs of human health damage, 1.11 × 10⁻⁴ species.year of ecological loss, and USD 3488.82 of resource depletion. These results provide constructive references for the sustainable development of the mining industry and contribute to achieving China’s dual carbon targets through energy transformation and low-carbon technological innovation. Full article

This study presents a comprehensive review of various advanced methodologies that have been used to enhance the structural and thermal performance of masonry walls through innovative and sustainable retrofitting/upgrading techniques. Focusing on three primary approaches—mechanical/structural retrofitting, thermal retrofitting, and integrated (structural and thermal) retrofitting, this paper critically examines various masonry-strengthening strategies. Retrofitting techniques are categorized by material use and objectives. Fiber-based solutions include insulation materials, fiber composite mortar for strength, FRP for high-strength reinforcement, and TRM for durability. According to the relevant objectives, retrofitting can enhance structural stability (FRP, TRM), improve thermal insulation, or combine both for integrated performance. Particular emphasis is placed on the effectiveness of TRM systems, with a comparative analysis of man-made (glass, steel textile) and natural fiber-based TRM solutions. Regarding integrating natural fibers into TRM systems, this study highlights their potential as eco-friendly alternatives that reduce environmental impact while maintaining or improving structural integrity. Furthermore, it highlights and examines techniques for testing masonry walls. In this context, this review highlights the applicability of natural fiber as a sustainable building material in various retrofitting/upgrading solutions. Full article

Post-earthquake fires are typically of great concern for fire protection services, which are expected to be in high demand immediately after a strong earthquake. The post-earthquake functionality of fire stations is necessary after strong earthquakes to reduce potential fire damage and improve emergency services. A reliable assessment of the seismic vulnerability and expected damage for fire stations is therefore a necessary step towards the identification of the most vulnerable structures and the prioritization of seismic retrofit activities. This article presents the development of a methodology for the damage assessment of fire stations based on earthquakes scenarios. The framework is based on four models: seismic hazard, inventory, fragility and impact. The seismic hazard model represents ground shaking in terms of intensity measure at each station using a ground motion prediction equation for Eastern Canada. The inventory model categorizes all the fire stations in building classes based on construction material and seismic code level. The fragility model associates building classes with fragility functions that provide the relationship between intensity measure and expected damage probabilities. The impact model converts damage probabilities into a mean damage state. All Montreal fire stations were selected as case study demonstrations. Simulations were conducted by varying the epicenter location and magnitude for a total number of 345 scenarios. Simplified relationships that correlate the earthquake magnitude and expected damage were developed. The study showed that, for magnitude 6 earthquakes, 45% of stations on average would sustain at least moderate damage. The methodology is particularly useful for emergency planning and prioritization of seismic retrofit activities. Full article

Streets, as critical public space nexuses, require synergistic quality–utilization alignment—where quality without use signifies institutional inefficiency, and use without quality denotes operational ineffectiveness. Focusing on high-frequency pedestrian commuting streets (HFPCSs) that not only crucially mediate metropolitan mobility patterns but also shape citizens’ daily urban experiences and satisfaction, this study proposes a data-driven diagnostic framework for street quality–utilization assessment, integrating multi-source urban big data through a case study of Shenzhen. By integrating multi-source urban big data, we identify HFPCSs using LBS data and develop a multi-dimensional evaluation system that incorporates 1.07 million Points of Interest (POIs) for assessing convenience, utilizes DeepLabv3+ for the semantic segmentation of street view imagery to evaluate comfort, and leverages 15,374 km of road network data for accessibility analysis. The results expose dual mismatches: merely 2.15% of HFPCSs achieve balanced comfort–convenience–accessibility benchmarks, while over 70% of these are clustered in northern districts, exhibiting systematically inferior quality metrics across dimensions. Diagnostic analysis reveals specific planning and spatial configurations contributing to these disparities, informing targeted retrofitting strategies for priority street typologies. This approach establishes a replicable model for megacity street renewal, deploying supply–demand diagnostics to synchronize infrastructure upgrades with pedestrian flow realities. By bridging data insights with human-centric urban improvements, this framework demonstrates how smart city technologies can concretely address the quality–utilization paradox—advancing sustainable urbanism through evidence-based street transformations. Full article

The growing imperative for sustainable building retrofits has spurred significant interest in advanced photovoltaic (PV) solutions. This study evaluates the feasibility and competitiveness of incorporating CIGS thin-film photovoltaic (PV) modules into retrofit projects for aging buildings. By combining qualitative analyses of market and environmental factors with a quantitative multi-criteria index model, this research assesses CIGS performance across five critical dimensions: aesthetic, economic, safety, energy saving, and innovation. The weights assigned to each criterion were determined through expert evaluations derived from structured focus group discussions. The results demonstrate that CIGS exhibits substantial strengths in aesthetic, economic, safety, energy saving, and innovation while maintaining reasonable economic feasibility. The quantitative assessment demonstrated that CIGS thin-film solar cells received the highest overall score (88.92), surpassing silicon-based photovoltaics (86.03), window retrofitting (88.83), and facade cladding (82.21) in all five key metrics of aesthetics, economic feasibility, safety, energy efficiency, and innovation. The findings indicate that CIGS technology exhibits not only exceptional visual adaptability but also attains balanced performance with regard to environmental and structural metrics. This renders it a highly competitive and comprehensive solution for sustainable building retrofits. Full article

This paper introduces an innovative, environmentally sustainable, and climatic study analysing the impact of overhang depths on heating and cooling building energy demands in the Mediterranean Basin via dynamic energy simulations of a south-oriented reference residential building zone. The adopted bioclimatic approach aims at increasing building sustainability and suggests, for representative Köppen–Geiger climate subtypes, optimal overhang depths and climate-correlated depth domains. The definition of a large geoclimatic study based on 80 locations and the classification of results based on climate subtypes are two novelties introduced in this work. From the energy point of view, overhangs can reduce local building cooling needs by, on average, 27%, while decreasing the total final energy needs (Q_TOT) by 17%. A new approach is also introduced: comparing the energy reduction due to the addition of an overhang to commonly applied envelope retrofitting solutions, such as wall insulation or window substitutions. Overhangs show great potential in sites with arid climate subtypes and are more effective than other solutions in several locations. This study underlines the need to increase the adoption of passive cooling solutions by local retrofitting regulations in places with a Mediterranean climate, following a bio-regionalist approach able to increase the local buildings’ sustainable development. Full article

The building sector significantly contributes to global resource depletion and greenhouse gas emissions, necessitating integrated approaches to evaluate both environmental and economic performance. This study developed a sustainability-oriented assessment framework—applied in a Chinese context—that integrates life cycle assessment (LCA), life cycle costing (LCC), and carbon financial optimization to evaluate the life cycle performance of prefabricated steel buildings. Using publicly available databases (CEADs, Ecoinvent, and the Chinese Life Cycle Database), the framework quantified cradle-to-grave environmental impacts across raw material extraction, prefabrication, transport, on-site assembly, operation, and end-of-life stages. Emissions were monetized using standardized emission factors and official cost coefficients, enabling environmental costs to be expressed in financial terms. A dynamic financial simulation module was incorporated to assess the effects of carbon price fluctuations and quota allocation schemes. Sensitivity analyses were performed to examine the influence of key variables such as retrofit investment costs, emission reduction efficiency, and carbon policy scenarios on financial returns. The results show that material production and operational energy use dominate life cycle carbon emissions, jointly contributing more than 90% of the total impacts. Moderate decarbonization investments—such as HVAC upgrades and improved insulation—can achieve positive net economic returns under baseline carbon pricing. This integrated, data-driven framework serves as a practical decision-support tool for policymakers and industry stakeholders. It is adaptable across different regions and material systems, supporting the global transition toward low-carbon and financially viable construction practices. Full article

This study proposes a sustainable multi-criteria optimization framework for the energy retrofit of collective residential buildings in Algeria, particularly those constructed between the 1970s and 1980s. Through on-site surveys, energy consumption analysis, and seasonal temperature measurements, the high energy demand of these buildings was confirmed. Using EnergyPlus simulations based on Meteoblue weather data, 16 retrofit strategies were assessed—incorporating various insulating materials applied internally or externally (via rendering or cladding). The ELECTRE III decision-making tool was employed, supported by the Simos Revised Framework (SRF) for weighting environmental, economic, and social criteria. Results demonstrate that all strategies significantly reduce energy demand—by up to 72.5%, with reductions reaching 94.4% in winter and 43.5% in summer, depending on insulation type and placement. Improvements in indoor thermal comfort were also observed, with exterior insulation beneath cladding offering the best performance during winter, while exterior rendering also proved effective in the summer. The ELECTRE III analysis identified rock wool and polyurethane with fiber cement cladding as optimal insulation solutions. The proposed approach supports national energy policies and aligns with the Sustainable Development Goals (SDGs), offering a replicable model for large-scale building retrofits in similar climatic and architectural contexts. Full article

The hybridization of ADM-Type Rail Service Cars aims to enhance energy efficiency, environmental sustainability, and cost-effectiveness within Uzbekistan’s railway network. Diesel-powered service cars currently contribute to high fuel consumption, elevated emissions, and costly maintenance, necessitating a transition to hybrid technology. This study introduces an innovative “sequence of linear sets–torsion electric motor–wheel pairs” design, optimizing torque distribution and power efficiency for improved operational reliability. Through system modeling, performance simulations, and real-world field trials, the hybrid system demonstrates a 15% reduction in energy consumption, a 25% decrease in CO₂ emissions, and up to 30% lower maintenance costs compared to conventional diesel models. Additionally, the hybrid technology enhances operational flexibility, allowing seamless functionality on both electrified and non-electrified railway lines. From an economic perspective, retrofitting existing service cars instead of full fleet replacement provides a cost-effective alternative, offering an estimated 10-year return on investment (ROI) through fuel savings and reduced downtime. This initiative directly supports Uzbekistan’s Green Development Strategy and railway modernization plans while holding significant commercialization potential in Central Asia and other regions with aging railway infrastructure. By addressing technical scalability, regulatory compliance, and economic feasibility, this study proposes a practical and timely hybrid retrofit solution for sustainable railway operations, aligning current industry needs with long-term environmental and financial benefits. Full article

Livestock buildings in rural areas are increasingly recognized for their environmental impact, yet few studies provide applied, scenario-based evaluations to guide retrofit interventions. While the existing literature acknowledges the environmental burden of livestock facilities, it often lacks operationally grounded analyses applicable to real-world agricultural contexts. This paper proposes an original integration of experimental climatic monitoring and life cycle assessment (LCA) to evaluate retrofit scenarios for energy efficiency in real poultry farming contexts. Based on an accurate climatic monitoring campaign conducted on-site during the spring and summer periods, relevant data were collected on air temperature, humidity, wind speed, and solar radiation affecting two poultry tunnels in central Italy, highlighting the need for thermal mitigation. The comparison between the observed operational scenario and the hypothesized improved scenario, involving energy supply from photovoltaic sources, evaluated using the PVGIS tool, demonstrated a significant reduction in environmental impact, with a 33.4% decrease in global warming potential and a 26.1% reduction in energy consumption. This study combines experimental on-site climatic data collection with comparative environmental evaluation using LCA methodology. The LCA approach, which guided the entire study, highlighted how the energy efficiency gained through solar panels adequately offsets their production and maintenance costs over the long term. These findings offer a replicable model for energy retrofits in rural livestock facilities, contributing to both environmental goals and rural resilience. Full article

Combustion and hydrolysis of lignocellulosic biomass generate renewable energy and biofuels, but also yield by-products, such as biomass combustion ash (BCA) and waste lignin (WL). This study investigates the reuse of these by-products in cement mortars, promoting circular economy principles and sustainable construction practices. The addition of BCA at 1–10% improved mortar consistency, homogeneity, and adhesion—most notably, formulations with 5–10% BCA increased adhesion to EPS by up to 4.3%, and compressive strength remained above the 20 MPa threshold. WL additions of 0.5–1% enhanced viscosity and adhesion to both mineral and EPS substrates, with a 0.2% WL dosage improving adhesion to EPS by 9.4% compared to the control sample. Life Cycle Assessment (LCA) confirmed a reduction in the carbon footprint by up to 14% (from 1509.5 to 1297.5 Mg CO₂/year), while VOC emissions remained within acceptable limits. Leachability tests confirmed safe environmental performance. The results validate BCA and WL as functional and eco-efficient additives in cementitious composites suitable for thermal retrofitting. Full article

Dutch housing associations, being semi-public construction clients, have been assigned an important role in helping to realize the national goal of a CO₂-neutral housing stock by 2050. To achieve this goal, a growing number of housing associations have added sustainable retrofit projects into multi-year programs. Those programs are being implemented by entering into strategic partnerships with retrofit contractors. The aim of this paper is to explore the rationale behind this asset and property management approach, the process, and the organizational conditions and consequences for the partners involved. To do so, a cumulative case study for research, including seven cases, was conducted. The findings show that the rationale is primarily about improving and accelerating the retrofit process by using the knowledge, competencies, and resources of the supply-side partners as effectively and efficiently as possible. This novel approach increases the retrofit rates and tenant satisfaction with the process. Trust is key in the collaboration between housing associations and contractors. For this, partner selection is an intensive and careful process. The factor hindering the upscaling of the approach is the cultural and organizational changes needed on both the demand and supply side. Full article