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One way to avoid ground congestion is to take to the sky, using vertical take-off and landing craft or 'VTOL'. This study examines opportunities, costs, and energy impacts for an eVTOL (electric VTOL) system across the Austin, Texas region. Using different demand levels and VTOL sizes (4 and 8 seaters), we estimate average minimum costs of $24.84 per person-trip and $0.98 per person-kilometer using 4-seaters, which is less than current ride-hailing costs in U.S. cities. However, ride-hailing is door-to-door, while eVTOLs rely on stations, with non-negligible access and egress costs. We find 4-seaters offer higher energy and greenhouse gas (GHG) savings, based on the Texas power grid's current feedstocks, with eVTOL GHG emissions similar to those of all-electric cars, in operation: about 70 grams per passenger-kilometer. But an eVTOL's lifetime emissions are estimated to be twice those of electric cars (per passenger-kilometer traveled). [ABSTRACT FROM AUTHOR]

The life-cycle duration (TLC) is typically assumed constant in pavement life-cycle analysis. The added scientific value of this paper is that (TLC) is considered a variable parameter to be estimated from the performance curve using a variable terminal condition rating. A variable (TLC) requires using the equivalent annual value (EAV) instead of the net present value for cost estimation. The life-cycle performance (LCP) curve is constructed using two routine maintenance cycles separated by one major rehabilitation action. The time parameters associated with LCP curve are estimated from the inverse performance function based on the initial, present and terminal condition ratings. The equivalent annual cost and performance associated with a particular LCP curve are used to compute cost/performance (C/P) ratio for optimal maintenance and rehabilitation (M&R) plan selection. The EAV represents the costs of two routine maintenance cycles and one major rehabilitation action. Sample results obtained from three case studies have indicated the reliability of the proposed LCA approach in yielding optimal M&R plans. At the project-level, the optimal M&R plan associated with 7 m/km terminal IRI value resulted in (0.949) minimal (C/P) value. However, the optimal M&R plan with 3.25 terminal PSI yielded (1.50) minimal (C/P) value. [ABSTRACT FROM AUTHOR]

The life-cycle duration (TLC) is typically assumed constant in pavement life-cycle analysis. The added scientific value of this paper is that (TLC) is considered a variable parameter to be estimated from the performance curve using a variable terminal condition rating. A variable (TLC) requires using the equivalent annual value (EAV) instead of the net present value for cost estimation. The life-cycle performance (LCP) curve is constructed using two routine maintenance cycles separated by one major rehabilitation action. The time parameters associated with LCP curve are estimated from the inverse performance function based on the initial, present and terminal condition ratings. The equivalent annual cost and performance associated with a particular LCP curve are used to compute cost/performance (C/P) ratio for optimal maintenance and rehabilitation (M&R) plan selection. The EAV represents the costs of two routine maintenance cycles and one major rehabilitation action. Sample results obtained from three case studies have indicated the reliability of the proposed LCA approach in yielding optimal M&R plans. At the project-level, the optimal M&R plan associated with 7 m/km terminal IRI value resulted in (0.949) minimal (C/P) value. However, the optimal M&R plan with 3.25 terminal PSI yielded (1.50) minimal (C/P) value.

While there is a strong cross-sectional association between social class and political attitudes, recent research—based on longitudinal data—finds that changes in class are, at most, weakly related to changes in such attitudes. One common explanation for this finding is that early life socialization affects both social class and political attitudes and that class has little, if any, direct effect on them. In this manuscript, we explore an alternative explanation that centers on the importance of cumulative class experiences for the long-term evolution of attitudes. To evaluate this perspective, we leverage data from the British Household Panel Survey, which contains measures of economic values that span up to 16 years, as well as complete work-life histories of respondents that allow us to track individual class experiences over people's life span. Our findings show that cumulative class experiences are strongly associated with the development of economic values. [ABSTRACT FROM AUTHOR]

Abstract In the strategy to combat climate change that has been caused by the world's overdependence on fossil fuels, current research is focusing on the decarbonisation of the energy sector through the production of renewable cleaner energy, such as biofuels. Spent coffee grounds (SCGs), the waste stream of the coffee brewing industry, are a potential feedstock for the production of valuable products, including biofuels. However, the environmental implications for the valorisation of this valuable waste need to be investigated. This study assesses the environmental impacts of six biomass‐to‐fuel processing technologies using SCGs as a feedstock, with the aim of identifying the most environmentally friendly technology. A cradle‐to‐gate life‐cycle assessment (LCA) was conducted on fast pyrolysis, fermentation, anaerobic digestion (AD), hydrothermal liquefaction (HTL), gasification, and biodiesel production. The mass and energy balances obtained from Aspen Plus simulations served as the life‐cycle inventory data. Using the ReCiPe 2016 midpoint (H) and Eco‐Indicator 99 as the assessment methods, potential environmental impacts were calculated in OpenLCA software. Electricity generation and carbon dioxide emissions were the biggest contributors of environmental impacts. For each category, the maximum result was set to 100% and the results of the other variants were displayed in relation to this result. AD, with the smallest total weighted score (160), was the most environmentally friendly biomass‐to‐fuel processing route, while HTL, with the biggest total weighted score (893), was the worst. A sensitivity analysis indicated that the environmental performance of biofuel production from SCGs was highly influenced by energy input flows and the source of energy generation.

Recent global policy initiatives aimed at reducing forest degradation require practical definitions of degradation that are readily monitored. However, consistent approaches for monitoring forest degradation over the long term and at broad scales are lacking. We quantified the long‐term effects of intensive wood harvest on above‐ground carbon and biodiversity at fine resolutions (30 m2) and broad scales (New Brunswick, Canada; 72,908 km2). Model predictions for above‐ground biomass were highly correlated with independent data (r = 0.77). After accounting for carbon stored in wood products, net CO2 emissions from forests for the region from 1985 to 2020 were 141 CO2e Tg (4.02 TgCO2e year−1; 32% of all reported emissions). We found strong positive correlations between locations with declines in above‐ground carbon and habitats for old‐forest bird species, which have lost > 20% habitat over 35 years. High congruence between biodiversity and forest carbon offers potential for policy incentives to conserve both objectives simultaneously and slow rates of forest degradation. These methods could be used to track forest degradation for managed forest regions worldwide. [ABSTRACT FROM AUTHOR]

In the strategy to combat climate change that has been caused by the world's overdependence on fossil fuels, current research is focusing on the decarbonisation of the energy sector through the production of renewable cleaner energy, such as biofuels. Spent coffee grounds (SCGs), the waste stream of the coffee brewing industry, are a potential feedstock for the production of valuable products, including biofuels. However, the environmental implications for the valorisation of this valuable waste need to be investigated. This study assesses the environmental impacts of six biomass‐to‐fuel processing technologies using SCGs as a feedstock, with the aim of identifying the most environmentally friendly technology. A cradle‐to‐gate life‐cycle assessment (LCA) was conducted on fast pyrolysis, fermentation, anaerobic digestion (AD), hydrothermal liquefaction (HTL), gasification, and biodiesel production. The mass and energy balances obtained from Aspen Plus simulations served as the life‐cycle inventory data. Using the ReCiPe 2016 midpoint (H) and Eco‐Indicator 99 as the assessment methods, potential environmental impacts were calculated in OpenLCA software. Electricity generation and carbon dioxide emissions were the biggest contributors of environmental impacts. For each category, the maximum result was set to 100% and the results of the other variants were displayed in relation to this result. AD, with the smallest total weighted score (160), was the most environmentally friendly biomass‐to‐fuel processing route, while HTL, with the biggest total weighted score (893), was the worst. A sensitivity analysis indicated that the environmental performance of biofuel production from SCGs was highly influenced by energy input flows and the source of energy generation. [ABSTRACT FROM AUTHOR]

Hydrogen is a zero-carbon energy carrier with potential to decarbonize industrial and transportation sectors, but its life-cycle greenhouse gas (GHG) emissions depend on its energy supply chain and carbon management measures (e.g., carbon capture and storage). Global support for clean hydrogen production and use has recently intensified. In the United States, Congress passed several laws that incentivize the production and use of renewable and low-carbon hydrogen, such as the Bipartisan Infrastructure Law (BIL) in 2021 and the Inflation Reduction Act (IRA) in 2022, which provides tax credits of up to $3/kg depending on the carbon intensity of the produced hydrogen. A comprehensive life-cycle accounting of GHG emissions associated with hydrogen production is needed to determine the carbon intensity of hydrogen throughout its value chain. In the United States, Argonne's R&D GREET® (Greenhouse Gases, Regulated emissions, and Energy use in Technologies) model has been widely used for hydrogen carbon intensity calculations. This paper describes the major hydrogen technology pathways considered in the United States and provides data sources and carbon intensity results for each of the hydrogen production and delivery pathways using consistent system boundaries and most recent technology performance and supply chain data. [ABSTRACT FROM AUTHOR]

Brazil is the major producer and exporter of orange juice in the world. Orange peel (OP) derived from juice processing, the main industrial by-product, is generally intended for animal feed without further revalorization. The frozen concentrated orange juice (FCOJ) productive chain presents high energy requirements. A possible route to revalue OP and to generate renewable energy is the anaerobic digestion (AD) technology, for which a previous assessment of the theoretical electricity generation from biogas combustion indicated that 0.017 MWh per ton of OP could be obtained. Aiming to support a clean and renewable energy transition for the citrus industry, a thorough literature search regarding OP revalorization routes was made to investigate the potential energy recovery from AD technology for the Brazilian's FCOJ scenario. The results indicated that the AD of the total OP amount derived from industry could be enough to supply from 71 to 111% of the total energy consumption in the FCOJ chain (from the initial step, i.e., permanent orange fields and their fertilization technologies—organic or conventional systems—until the industrial energy requirements). Despite the agricultural system (organic or conventional), a positive energy replacement can be achieved through the adoption of AD. Finally, the study concluded that FCOJ industry presents an opportunity to obtain energy savings. Moreover, for the Brazilian FCOJ production, OP revalorization could mitigate 9.74 tCO2eq/year of GHG. A decarbonization strategy and a healthy circular economy for the Brazilian citrus industry could flourish from AD adoption as an alternative route for OP disposal. [ABSTRACT FROM AUTHOR]

The United States' focus on decarbonization has spawned interest among policymakers in deploying water electrolysis technology for clean hydrogen production. However, water electrolyzers also raise concerns regarding their substantial use of carbon-intensive materials. Here, we conduct a comprehensive life-cycle analysis (LCA) of three prominent water electrolyzer technologies to investigate the environmental implications of their manufacturing and life cycles under different energy sources. All electrolyzer technologies employing low-carbon energy (nuclear, solar, or wind) exhibit life-cycle greenhouse gas (GHG) emissions of 0.3–2.4 kg-CO 2-eq /kg-H 2. This is significantly lower than the corresponding GHG emissions for hydrogen production via both conventional steam methane reforming and alternative autothermal reforming with carbon capture and storage (by > 50%). The well-to-gate GHG emissions of low-carbon electrolyzers (0–0.36 kg-CO 2-eq /kg-H 2) qualify for Tier I of the production tax credit in the U.S.' Inflation Reduction Act of 2022, indicating their suitability for producing decarbonized hydrogen under this program. • Compares the life-cycle environmental impacts of SOEC, PEM, and AEC electrolyzers • Ni, Ti, Si, steel, Cu, and energy use dominate electrolyzers' manufacturing impacts • Electricity generation-related impacts dictate electrolyzers' life-cycle impacts • Low-carbon electrolysis outperforms other H 2 -producing technologies over life-cycle • Decarbonized H 2 production requires clean material production and low-carbon energy [ABSTRACT FROM AUTHOR]

Although scholars have developed simulation models and analyzed bankability criteria in numerous papers to enhance the financial outcomes of Public-Private Partnerships (PPPs), the intersection between both fields considering alternatives to assess the financial impact of flexibility in both scope and financing, remains underdeveloped. To address this gap, this paper introduces a financial model that assesses the financial impact of suitable life-cycle flexibility alternatives while coexisting with revenue performance alterations in each project phase within toll road PPPs. This model serves as a tool to gain insight into the planning of strategic actions to implement flexibility in both scope and financing. Based on system dynamics and validated using financial data from two toll road PPPs in India and East Europe, simulation results suggest that two key drivers (capital expenditures and debt repayment period) have the greatest influence on financial performance. Findings support the implementation of flexible scopes to effectively address the most influential exogenous factor impacting the financial performance of PPPs, namely traffic shortfalls. This model provides a suitable tool for assessing the life-cycle economic sustainability of PPPs in uncertain and complex environments. [ABSTRACT FROM AUTHOR]

Approximately 11% of the world’s population lives within 10 km of an ocean coastline, a percentage that is likely to increase during the remainder of the 21st century due to urbanization and economic development. In the presence of climate change, coastal communities will be threatened by increasing damages due to sea-level rise (SLR), accompanied by hurricanes, storm surges and coastal inundation, shoreline erosion, and seawater intrusion into the soil. While the past decade has seen numerous proposals for coastal protection using adaptation methods to deal with the deep uncertainties associated with a changing climate, our review of the potential impact of SLR on the resilience of coastal communities reveals that these adaptation methods have not been informed by community resilience or recovery goals. Moreover, since SLR is likely to continue over the next century, periodic changes to these community goals may be necessary for public planning and risk mitigation. Finally, community policy development must be based on a quantitative risk-informed life-cycle basis to develop public support for the substantial public investments required. We propose potential research directions to identify effective adaptation methods based on the gaps identified in our review, culminating in a decision framework that is informed by community resilience goals and metrics and risk analysis over community infrastructure life cycles. [ABSTRACT FROM AUTHOR]

To address environmental challenges, the Architecture, Engineering, Construction, and Operations (AECO) industry, which is known for its high resource consumption and waste production, needs to switch to a circular economy (CE). This approach focuses on reducing, recycling, and reusing materials to narrow, slow, and close material loops. However, one of the main problems which the AECO industry is still facing is the lack of common, standardized, and automated procedures to consider the recyclability and presence of hazardous materials. To address this problem, this study focuses on extending the recyclability rate from the material to building scale, considering the presence of hazardous materials based on the European Waste Catalogue (EWC), hence defining a new KPI. It adopts Building Information Modelling (BIM) and Industry Foundation Classes (IFCs) and integrates them with bespoke programming in Python to develop a standardized and automated procedure that complies with Italian regulations. The new KPI will help clients and designers to rate the overall recyclability of a building and to choose the best combination of materials and components. The procedure includes data acquisition, transmission, and data/model integration, resulting in practical and trackable measures that could be globally scalable. Scenario analyses are also developed to consider the impact of maintenance attitude on waste production. [ABSTRACT FROM AUTHOR]

Hydrogen is a zero-carbon energy carrier with potential to decarbonize industrial and transportation sectors, but its life-cycle greenhouse gas (GHG) emissions depend on its energy supply chain and carbon management measures (e.g., carbon capture and storage). Global support for clean hydrogen production and use has recently intensified. In the United States, Congress passed several laws that incentivize the production and use of renewable and low-carbon hydrogen, such as the Bipartisan Infrastructure Law (BIL) in 2021 and the Inflation Reduction Act (IRA) in 2022, which provides tax credits of up to $3/kg depending on the carbon intensity of the produced hydrogen. A comprehensive life-cycle accounting of GHG emissions associated with hydrogen production is needed to determine the carbon intensity of hydrogen throughout its value chain. In the United States, Argonne’s R&D GREET® (Greenhouse Gases, Regulated emissions, and Energy use in Technologies) model has been widely used for hydrogen carbon intensity calculations. This paper describes the major hydrogen technology pathways considered in the United States and provides data sources and carbon intensity results for each of the hydrogen production and delivery pathways using consistent system boundaries and most recent technology performance and supply chain data.

Risk managers as corporate stewards are important gatekeepers in enterprises and they are essential to managing risks. Relatedly, a more accurate evaluation of the risk factors allows a well-founded decision-making process and reduces the number of surprising situations that could occur especially in volatile markets. Forward-looking risk management increases entrepreneurial resilience because risk factors are already estimated at an earlier stage in the corresponding risk analysis. Furthermore, the range of potential solutions can be estimated in a successive way. These aspects are relevant especially for products with follow-up effects. Such new product bundles are typical in current businesses. They require a more precise risk analysis, which allows an effective view of the life-cycles of the whole products and the customer relationships. Within well-founded risk decomposition, the existing risk can be managed appropriately. The following study presents a special life-cycle approach for evaluating products and customers in risky situations. Especially for important management decisions, such an approach is necessary, given that only a few products or customers can have a major influence on the success of the enterprise. Therefore, a systematic risk-oriented approach is essential that adequately identifies, assesses and controls the risk factors and enables agile adaptability for fast changes. Considering the risk management perspective, simulation techniques are a useful approach to solve sophisticated decision situations. The applicability of this concept is demonstrated using a computation example reflecting real-world circumstances. The presented approach is broadly defined. That is the reason why the approach can also be transferred to other sectors. [ABSTRACT FROM AUTHOR]

The sustainability of cement concrete is always a subject of concern and hence, less polluting concrete alternatives are being explored. Geopolymer concrete can be an alternative, which may be partly or fully cement-free. However, there exists a huge gap in the knowledge of quantification for ecological advancements that can be achieved. This study reports on the life cycle assessment (LCA) of five different geopolymer concrete mixes made up of ternary blends of sugarcane bagasse ash, blast furnace slag and fly ash. The results coupled with 28-day mechanical test results were compared with traditional cement concrete of similar grade. Correlation analysis was carried out among the obtained results to determine Pearson's coefficient and Spearman's rho factor. The aspect of cost and embodied energy was also studied simultaneously. The analyses showed that conventional concrete is more harmful in all ecological impact categories as compared to other alternative concretes except majorly Ozone layer depletion, Carcinogens and Mineral extraction. The sugarcane bagasse ash-based geopolymer concrete mixtures were also found to be cost and embodied energy-effective as compared to traditional concrete. [ABSTRACT FROM AUTHOR]

Hydrogen production via water electrolysis is a promising and evolving technology. The solid oxide electrolysis cell (SOEC) is one of the several technologies for this purpose. They are alternatives to the traditional hydrogen production from fossil fuels to enhance global energy decarbonization. However, in the bid for sustainability and a green economy, these technologies are not free from causing some environmental burdens. Using life cycle assessment (LCA), the greenhouse gas emission and degree of environmental impacts by these technologies can be identified and measured throughout their lifespan. This study addresses how to quantify these CO 2 emission impacts for an electrolytic system with different energy sources. The LCA of a novel integrated hydrogen production SOEC system with energy from solar photovoltaic and bituminous powerplant is performed using simaPro, the leading global LCA solution software. Measuring the environmental impact of the electrolytic operation in terms of weight, the bituminous powerplant poses damage which is, on average 700% more than solar PV. The thermal-to-hydrogen efficiency of the SOEC system is 56%, and a probable 28% reduction in carbon footprint with heat integration. The steam generation and the manufacturing of the SOEC have a very high environmental impact potential on the system. We recommend LCA and net energy analysis is carried out for every new hydrogen technology and adequate comparison to enhance sustainable and green economy. • Detailed cradle-to-gate life cycle assessment is carried out for an integrated solid oxide electrolytic cell (SOEC) system. • Carbon footprint can be reduced by 28% in the system with adequate heat integration. • Solar photovoltaic (PV) is an environmentally benign energy source for SOEC operations. • Bituminous powerplant poses environmental damage on average 700% more than solar PV. • Improved balance of plant (BoP) design is key to sustainable large-scale hydrogen production. [ABSTRACT FROM AUTHOR]

Hydrogen refueling stations (HRSs) are crucial infrastructures for the advancement of hydrogen energy. To promote and construct HRSs, a cost-benefit analysis is essential. Factors such as hydrogen transportation, storage, production technology, and subsidy policies can impact the costs. This paper aims to analyze the economics of HRSs under four operation modes, ie., on-site hydrogen production, off-site production with pipeline transportation, off-site production with tube trailer, and off-site production with liquid hydrogen tanker. Two life-cycle analysis models, an annualized cost model for hydrogen transportation and a levelized cost model for HRSs, are established for economic assessment. The study reveals that hydrogen supply costs account for over 50% of the LCOH for off-site station, and power costs drive up the LCOH for on-site station. Among the four operation modes, off-site station with pipeline is most economical, and the cost advantage increases as pipeline capacity utilization rate reaches 100%, but decreases as it drops to 20%. off-site station with long tubes is economical within 300 km, and off-site station with liquid hydrogen tankers is more economical within 300km∼1,000 km. On-site hydrogen production by water electrolysis is not economical at a cost of 35.24 CNY/kg. The optimal operation scheme under different hydrogen source distances is proposed. • An annualized cost model for hydrogen transportation modes and A levelized cost model for HRSs were established. • The comprehensive costs analysis throughout the full life cycle was conducted in four different operation modes of HRSs. • The factors affecting HRS costs were analyzed in depth:hydrogen source distance, pipeline utilization, and cost structure. • On-site hydrogen production in integrated station is not yet economically feasible. [ABSTRACT FROM AUTHOR]

Rotor and stator support structures of significant size and mass are required to withstand the considerable loads that direct-drive wind turbine electrical generators face to maintain an air-gap clearance that is open and stable. With the increase of scale, reducing the weight and environmental impact of these support structures is believed to be one of the key components to unlocking the true potential of direct-drive generators. An investigation on the electrical generator rotor structure of the IEA 15 MW offshore reference wind turbine was conducted. An integrated approach that considered the environmental impact, including the manufacturing energy usage and CO2 footprint, as well as the financial repercussions of structural parameter modifications as they are optimised was followed, making use of distinct commercial pieces of software. The rotor structure was parametrically optimised, and its operating loading conditions were evaluated at various size scales. The study determined that the effect of thermal loading is significant, which forces the designer to augment the mass to comply with the imposed structural requirements. The ensuing life-cycle assessment showed an increase in the environmental impact due to the consideration of this particular load, whose effect in structural deflection and stress has been typically underestimated.

The objective of this study was to evaluate the environmental performance of cow milk production in small and medium scale systems in Mexico, through life cycle analysis with a cradle to farm gate approach, for the period 2021-2030. The established functional unit was 1 kg of milk corrected for fat and protein. The impact assessment was carried out with the OpenLCA 1.11.0 software, using the ReCiPe method, considering seven impact categories: agricultural land occupation (ALO), marine ecotoxicity (ME), human toxicity (HT), climate change (CC), fossil depletion (FD), soil acidification (SA), and water depletion (WD). Among the main results of the research, the production of cattle feed was identified as the chief contributor to environmental loads in most of the categories with percentages above 71 %, while on-farm emissions contribute to the environmental loads for the CC (28 %), FD (26 %) and SA (59 %) categories. A comparison was made between pessimistic, base and optimistic scenarios for the years 2021 and 2030, which confirmed an improvement in environmental efficiency in the optimistic scenario, the increase in production volume represents a decrease of 6 % and 5 %, respectively, in the assessed impact categories. [ABSTRACT FROM AUTHOR]

Rotor and stator support structures of significant size and mass are required to withstand the considerable loads that direct-drive wind turbine electrical generators face to maintain an air-gap clearance that is open and stable. With the increase of scale, reducing the weight and environmental impact of these support structures is believed to be one of the key components to unlocking the true potential of direct-drive generators. An investigation on the electrical generator rotor structure of the IEA 15 MW offshore reference wind turbine was conducted. An integrated approach that considered the environmental impact, including the manufacturing energy usage and CO2 footprint, as well as the financial repercussions of structural parameter modifications as they are optimised was followed, making use of distinct commercial pieces of software. The rotor structure was parametrically optimised, and its operating loading conditions were evaluated at various size scales. The study determined that the effect of thermal loading is significant, which forces the designer to augment the mass to comply with the imposed structural requirements. The ensuing life-cycle assessment showed an increase in the environmental impact due to the consideration of this particular load, whose effect in structural deflection and stress has been typically underestimated. [ABSTRACT FROM AUTHOR]

Despite rapid advances in urban transit electrification, the progress of systematic planning and management of the electric bus (EB) fleet is falling behind. In this research, the fundamental issues affecting the nascent EB system are first reviewed, including charging station deployment, battery sizing, bus scheduling, and life-cycle analysis. At present, EB systems are planned and operated in a sequential manner, with bus scheduling occurring after the bus fleet and infrastructure have been deployed, resulting in low resource utilization or waste. We propose a mixed-integer programming model to consolidate charging station deployment and bus fleet management with the lowest possible life-cycle costs (LCCs), consisting of ownership, operation, maintenance, and emissions expenses, thereby narrowing the gap between optimal planning and operations. A tailored branch-and-price approach is further introduced to reduce the computational effort required for finding optimal solutions. Analytical results of a real-world case show that, compared with the current bus operational strategies and charging station layout, the LCC of one bus line can be decreased significantly by 30.4%. The proposed research not only performs life-cycle analysis but also provides transport authorities and operators with reliable charger deployment and bus schedules for single- and multi-line services, both of which are critical requirements for decision support in future transit systems with high electrification penetration, helping to accelerate the transition to sustainable mobility.

Design decisions normally consider the building's operational phase as the main criterion to reduce energy expenses in a building. In less efficient buildings, reducing the operational energy becomes the most important aspect to address in the design, construction and operational phases, for it represents the highest life cycle energy flow. However, energy-efficient solutions often reduce operational energy demand by increasing the building's embodied energy and greenhouse gas emissions, which have been overlooked in energy performance analyses. This work aims at investigating the operational energy and the consequent embodied impacts resulting from the retrofit of the window frame of mixed-mode office buildings located in a hot climate, with a focus on reducing the cooling energy demand. The method consists of an experimental study based on a case study, in which the EnergyPlus and the SimaPro software tools are used to evaluate the operational energy and the environmental impacts. Results showed that reducing the WWR and increasing the window opening factor conveyed operational energy savings but in some retrofit scenarios tested, these retrofit measures were counterproductive from the CED and GWP perspective. The main scientific contribution of this work is understanding the importance of the building analysis from a life-cycle approach. The results obtained can assist companies and designers to make their decisions from a broader environmental perspective.

Direct-drive generators are recognised for their low maintenance compared with conventional drivetrains, largely due to their fewer working parts. However, consequent to low-speed operation, these machines necessitate large diameters and are subject to rigorous stiffness requirements. Significant internal and external forces influence structural integrity, so to design them efficiently, consideration of all operating parameters is imperative. Therefore, through Finite Element Analysis, this paper sets out to quantify the influence of each operating parameter on the integrity of a parametrically optimised rotor structure under established operating conditions and introduces operating temperature to the current models. An environmental impact analysis of the optimised rotor structure and cost analyses of both the optimised and unaltered structures are carried out simultaneous to the design process. We find the use of parameter optimisation alone to be insufficient for rotor structures of this scale due to high increased mass and costs of manufacture. A significant finding from this study is that the thermal effects on large-scale direct-drive generator structures may be vastly underestimated and have a much greater influence on structural integrity than first thought. [ABSTRACT FROM AUTHOR]

To address environmental challenges, the Architecture, Engineering, Construction, and Operations (AECO) industry, which is known for its high resource consumption and waste production, needs to switch to a circular economy (CE). This approach focuses on reducing, recycling, and reusing materials to narrow, slow, and close material loops. However, one of the main problems which the AECO industry is still facing is the lack of common, standardized, and automated procedures to consider the recyclability and presence of hazardous materials. To address this problem, this study focuses on extending the recyclability rate from the material to building scale, considering the presence of hazardous materials based on the European Waste Catalogue (EWC), hence defining a new KPI. It adopts Building Information Modelling (BIM) and Industry Foundation Classes (IFCs) and integrates them with bespoke programming in Python to develop a standardized and automated procedure that complies with Italian regulations. The new KPI will help clients and designers to rate the overall recyclability of a building and to choose the best combination of materials and components. The procedure includes data acquisition, transmission, and data/model integration, resulting in practical and trackable measures that could be globally scalable. Scenario analyses are also developed to consider the impact of maintenance attitude on waste production.

This study presents a life‐cycle analysis (LCA) of the greenhouse gas (GHG) emissions of biodiesel (BD) and renewable diesel (RD) produced from soybean varieties with altered oil profiles and meal composition. The varieties evaluated include those with high oleic oil content (78% of oil being oleic oil vs. the current content of 25%), high lipid content (25% vs. the current content of 19%) or high protein content (45% vs. the current content of 35%). The results suggest that high‐oleic soybean oil could reduce GHG emissions of RD by 1 g CO2e/MJ by reducing hydrogen consumption in the hydro‐treating stage of RD production. With the default allocation method (mass‐based allocation between oil and meal), changes in lipid and protein contents have negligible impacts on GHG emissions of BD/RD pathways. Since high‐protein soybean meal has a higher nutrient value, we employed the market‐based allocation for sensitivity analysis. Assuming a market price of $1.17/dry kg and an average of two substitute feeds with similar protein contents (corn gluten and fish meal), the allocation factor for soybean meal increases from 63 to 81%. Compared with the results for the case with commodity soybean using mass allocation, GHG emissions could be 1.9 and 1.8 g CO2e/MJ lower for BD and RD, respectively. In addition to product‐level LCA, we employed a land‐based LCA to evaluate the effect of soybean properties on product slates with the same land area and the associated displacement of conventional products. The results suggest that high‐lipid soybeans may offer more GHG savings than other varieties as the higher BD/RD yield replaces more fossil diesel. © 2023 UChicago Argonne, LLC, Operator of Argonne National Laboratory and Northrup, Ag. Biofuels, Bioproducts and Biorefining published by Society of Industrial Chemistry and John Wiley & Sons Ltd. [ABSTRACT FROM AUTHOR]

Due to its superior mechanical and durability performance, ultrahigh performance concrete (UHPC) has gained increasing applications worldwide. While studies have suggested different strategies to design reinforced UHPC beams, their resulting structural behavior is not yet well understood, and their carbon footprint has not been given considerable attention. Based on nonlinear finite element simulations and cradle-to-gate life-cycle analyses, this study compares the performance of two steel-reinforced concrete beams to steel-reinforced UHPC (R/UHPC) beams with the same flexural load capacity but different design strategies. Results show that an R/UHPC beam of the same cross-section but lower reinforcing ratio of a conventional concrete beam could show 166% higher carbon emission and 64% less deformation capacity than a control steel-reinforced concrete beam. On the other hand, a well-designed R/UHPC beam can (1) maintain the carbon footprint; (2) reduce the section size and steel bar usage by 50% and 30%–53%, respectively; and (3) show equivalent or higher service-level stiffness and ultimate deformation capacity. [ABSTRACT FROM AUTHOR]

This paper conducts a comprehensive analysis of the environmental impacts and costs associated with a floating photovoltaic (FPV)-powered green hydrogen production system for a ferry line in Türkiye, utilizing life cycle assessment (LCA) and life cycle cost assessment (LCCA) methods. The methodology involves regridding daily data from 13 Global Climate Models (GCMs) to a consistent 1° × 1° grid, comparing this data with ERA5 datasets using various statistical methods, and identifying the top four GCMs. These models are then used to forecast ambient temperature, wind speed, and solar radiation for 2023–2052. Based on these forecasts, the FPV system's component sizes are determined. The LCA, based on the GREET 2022 database, reveals that green hydrogen is the most environmentally friendly option, reducing global warming potential (GWP) by 77.5 % compared to marine diesel oil (MDO 0.1 % S), with more than 62 % of GWP for the hydrogen-powered ferry attributed to PV production. LCCA results indicate that, without subsidies, green hydrogen is not economically feasible for the selected inland ferry line. Carbon taxes are insufficient to bridge cost differences, highlighting the need for financial incentives. Reducing corporate tax to 10 % is identified as the most effective incentive, and the Production Tax Credit (PTC) option maximizes internal rates of return for green hydrogen producers. This study provides valuable insights for sustainable energy choices in maritime transport, emphasizing the importance of both environmental and economic considerations. • The green hydrogen-powered ferry line causes 77.5 % less GWP compared to MDO. • More than 62 % of GWP comes from the PV production. • Green hydrogen is not a feasible option without any subsidy. • The LCOH is estimated between 6.99 and 6.66 $/kgH 2 based on the scenario. • Financial incentives are more powerful tools compared to carbon taxes. [ABSTRACT FROM AUTHOR]

Bridges are subject to a plethora of deterioration phenomena, such as corrosion, fatigue, and damaging events (e.g., truck impacts and earthquakes) that can affect their performance and compromise functionality and safety. These challenges, along with the expansion of physical infrastructures and limited economic resources, underscore the need for effective management systems to enhance the efficiency of maintenance activities. To address this need, bridge operators have developed Bridge Management Systems (BMSs), which assist in ensuring safe operations while optimizing budget allocation and intervention strategies. Existing state-of-the-art studies on BMSs, dating back several years, primarily focus on specific aspects of BMSs and do not provide exhaustive insight into the implemented processes. Consequently, a comprehensive analysis of the entire process is currently lacking. This review organizes and discusses the key features of existing BMSs and introduces a novel definition of BMS modules—data management, diagnosis, prognosis, and decision-making—where consensus is currently lacking. The paper covers the historical and current practices of the most common BMSs, outlining the main principles of each phase along with their critical aspects and future trends. • Novel insights into BMS: data management, diagnosis, prognosis, decision-making. • Review of historical and current BMS practices, key principles, future trends. • Advancements in data collection: from visual inspections to SHM. • Identification of BMS limitations, exploration of emerging technologies. • Emphasis on the evolving landscape of BMS towards digitalization and automation. [ABSTRACT FROM AUTHOR]

A recent focus on sustainable infrastructure has cast the use of concrete for construction of infrastructure in a negative light because of the relatively high amounts of carbon dioxide produced during the production of cement. In this work, the total greenhouse gas (GHG) emissions of a concrete dome structure (with and without soil covering) are compared to those of a typical code-compliant wooden-frame structure with respect to both production-related emissions and energy consumption over the life of the structure. This comparison was addressed through a combination of computational thermal modeling, validation of model results based on temperature measurements of a to-scale concrete dome structure, and a life-cycle analysis of GHG emissions during the product stage and the operational energy component of the use stage of the structures. While the concrete dome structure contains more embodied carbon than a typical wooden-frame structure of comparable footprint, the analysis performed in this research indicates that total GHG emissions over the life of the structure are significantly lower for the concrete dome structure. • Concrete dome structures are much less prone to temperature fluctuations than typical code-compliant wooden-frame structures. • Concrete dome structures may experience significantly less heat flux than typical code-compliant wooden-frame structures. • Concrete domes may have far lower greenhouse gas emissions than code-compliant wooden-frames over the lifetime of a building. • Earth-sheltering of a structure further reduces total energy consumption over the life of the structure. [ABSTRACT FROM AUTHOR]

With both global and national targets to reduce greenhouse gas (GHG) emissions the improvement of existing buildings will be key to realising these ambitions. How this can be achieved, and the impact of whole-life emissions from retrofit remains a key question. This paper investigates the potential of retrofit to reduce and limit lifecycle GHG emissions resulting from an existing house, typical of one of the predominant housing typologies in Northern Ireland. Through the use of lifecycle assessment a range of retrofit scenarios are considered for an early 20th century, solid wall, terraced house, to understand the impacts of retrofit on lifecycle emissions. A range of retrofit scenarios were modelled and simulated, considering both embodied and operational emissions over the building’s lifetime, to understand how net emissions can be reduced. The results show that although fabric and some technological measures can reduce emissions by over 60% when applied in isolation, a holistic approach is required to achieve the greatest reductions. Although operation remains the largest single source of emissions, the results also show the importance of taking a holistic approach to the assessment of retrofit with varying lifecycle stages responsible for considerable emissions. It is seen that emissions reductions of up to 99% may be possible when taking a holistic approach to retrofit and its assessment, considering whole-life emissions. This study highlights the potential benefits of retrofit and how it could be effectively applied to the existing housing stock in Northern Ireland creating low-emission or net-zero emission buildings.

Atmospheric carbon dioxide emanating from activities associated with the construction of buildings in the UK contributes approximately 16% of the uk's total emissions and will need to be reduced significantly to meet international agreements. Against this scenario, this paper presents a novel perspective for carbon accounting and trading that proposes the use of a platform for the uk construction industry as a possible solution. This suggestion assumes that taxation should be synchronised with phases of the entire life cycle of the building and that tax credits (or deficits) should remain an asset of the building itself. In this regard, a strategy is in place in the uk, but with gaps in how it will be implemented. To resolve these gaps, firstly, this paper explores and integrates three socio-technical components (i.e., carbon accounting, trading, and certification) that form an essential set of tools required for the management of taxes directed at property developers and construction companies. Then, it points out the need for a suite of computer-based systems to facilitate the recording of emissions information, the purchase of carbon offsets, and a way to access specialist financial services. As a result, a trading platform is conceptualised that makes use of blockchain technology as a foundation for future research. [ABSTRACT FROM AUTHOR]

Wall plaster production induces significant environmental impacts during its entire life as it consumes a high amount of cement and natural resources. Therefore, in sustainable development, industrial wastes are partially replaced to produce cementitious material to reduce environmental impacts. This study aims to identify the optimal environmental benefits from the waste-based cementitious materials that are used to produce wall plaster. Thus, this study involved conducting a comprehensive review of the mechanical and sustainable performance of industrial waste-based cementitious materials focused on wall construction. Then, an experimental test was conducted to ensure the appropriate mix design to enable the required compressive strength. A comparative analysis of mortar showed that it contained 15% (by weight) of fly ash, blast furnace slag, bottom ash, recycled glass, ferronickel slag, expanded polystyrene and wood ash using life-cycle assessment. The results show that mortar containing fly ash has lower environmental impacts in almost all impact categories (i.e., human health, the ecosystem and natural resources). Endpoint damage assessment of mortar mixtures expresses resource extraction cost as the most affected impact criteria. The replacement of globally consumed cement with 15% fly ash can contribute to monetary savings of up to USD 87.74 billion. The assessment clarifies the advantage of incorporating waste products in cement mortar, which allows policymakers to interpret the analysis for decision making. This study also found that the production of industrial wastes for mortar mixes has a significant impact on the environment. [ABSTRACT FROM AUTHOR]

In the present research work, the use of agro-industrial waste such as agave bagasse from the tequila industry was carried out. The agave bagasse was treated to obtain biosorbent and hydrochar materials. Direct Blue 86 was used as an adsorbate model to evaluate the performance of both materials. The adsorption studies showed an adsorption capacity of 6.49 mg g−1 in static and 17.7 mg g−1 in dynamic, associated with a physisorption process between functional groups of the material and the dye. The characterization of the biosorbent showed that the material was mainly composed of macroporous fibers with a surface area <5.0 m2 g−1. Elemental analysis showed a majority composition of C (57.19 wt%) and O (37.49 wt%). FTIR and XPS analyses showed that the material had C-O, C=O, -OH, O-C=O, and -NH2 surface groups. RAMAN and TGA were used to evaluate the composition, being cellulose (40.94%), lignin (20.15%), and hemicellulose (3.35%). Finally, the life-cycle assessment at a laboratory scale showed that the proposed biosorbent presents a 17% reduction in several environmental aspects compared to hydrochar, showing promise as an eco-friendly and highly efficient method for the remediation of water contaminated with dye, as well as being a promising alternative for the responsible management of solid waste generated by the tequila industry. [ABSTRACT FROM AUTHOR]