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Current international waste policy promotes the reduction and re-use of waste materials, and in some cases, specifically calls for the use of recycled materials in pavements. Consequently, there is a need to understand the performance of recycled materials in airport pavements, as well as the overall sustainability benefit. This paper reviews several recycled materials and their applications to asphalt concrete, cement concrete, and bound and unbound granular materials in the context of airport pavements. Additionally, it reviews sustainability quantification methods, as well as implementation challenges for using recycled materials in airport pavements. For comparing pavements with and without recycled materials, a triple bottom line approach is appropriate. The triple bottom line approach should use life cycle cost assessment and life cycle assessment for the financial and environmental impacts, respectively, as best-practice, with frameworks and guidelines already established. For social impacts, it is recommended to quantify the reduction in virgin material use which relates to intergenerational equity by ensuring access to materials by future generations. Because there are still implementation challenges for the airport pavement industry, principles are developed that aim to promote uptake of recycled materials. These principles include sorting and processing, minimising haulage distances, and ensuring performance of pavement layers through performance testing and performance-related specifications. [ABSTRACT FROM AUTHOR]

This article presents an active fault detection kit, applicable to low voltage single-phase electrical installations, in the prospect of the Zero Energy Building concept, integrating on-site renewable energy generation and energy storage. This simple, flexible, self-powered and compact kit is capable of detecting faults, such as power theft (meter tampering), unintentional islanding and neutral conductor loss. Its operation is based on harmonic voltage injection, in series with the electrical installation, through a low-power H-bridge inverter and a current transformer, along with the corresponding harmonic current measurement, to estimate the impedance and effectively detect faulty conditions; the fast and robust Goertzel algorithm is utilized. Moreover, it features IoT communication capabilities, employing the ESP32 microcontroller, to exchange data and information with the installation meters. The functionality and effective fault detection of the proposed device are validated, through experimental tests on a custom-developed hardware prototype; IoT connectivity and data uploading are experimentally tested and verified, too. Finally, a sustainability assessment study is performed, using the Life Cycle Cost Analysis tool.

Abstract Carbon-based nanodots have garnered recent interest for their simple synthesis and versatile utility, ranging from biomedical to (opto) electronic applications, evolving into a tunable and biocompatible material. Here, for the first time, a biochar (lotus leaf) derived carbon nanodots was synthesized through hydrothermal carbonization. The synthesized hollow spherical biochar was engineered via functionalization by grafting –SO3H active sites. The attained catalyst was broadly analyzed by XRD, FTIR, TGA, BET, SEM–EDX, TEM, and XPS analysis after which it was applied for the acetalization reaction of crude glycerol (a biodiesel by-product) to form solketal, a potential fuel additive to valorize the large waste stream generated from biodiesel industry. Employing the RSM-CCD methodology, the experimental matrix was executed, and subsequent data were scrutinized through multiple regressions to model a quadratic equation. Under specific reaction parameters—a reaction duration of 14 min, a molar ratio of 7.5:1, and a catalyst loading of 5.7 wt.%, maximum solketal yield (95.7%) was attained through the ultrasonication method. Finally, to conclude, life cycle cost analysis (LCCA) for solketal production was studied here which determined the overall cost of solketal production per kilogram to be 0.719 USD ($), indicating high commercial applicability.

Commercial Buildings release large volumes of greenhouse gases, expediting global warming. The commercial building industry accounts for 37% of global CO2 emissions. Geothermal energy technologies are an intriguing solution that provides a low-impact, emission-free, and cost-effective thermal fuel source for baseload energy production. Geothermal energy systems offer a potential solution to dramatically halt global warming and facilitate the transition to a carbon-neutral civilization. This study develops a framework for assessing the geothermal power capabilities of innovative house and district heating systems. The energy requirements are first assessed, and then the spatial evaluation of district heating infrastructure is carried out using a Python-based program. Economic comparisons between geothermal energy and fossil fuels are made using LCC analysis. Environmental impacts are measured by Life Cycle Analysis (LCA). This study compares geothermal energy to fossil fuels, and the LCA results show that geothermal energy has a low environmental impact. With a Net Present Value (NPV) of 34.81 USD, it displays economic viability as well as a satisfactory financial return. The study's findings show that geothermal energy has the ability to compete with fossil fuels in commercial heating applications while still being environmentally beneficial.

Carbon-based nanodots have garnered recent interest for their simple synthesis and versatile utility, ranging from biomedical to (opto) electronic applications, evolving into a tunable and biocompatible material. Here, for the first time, a biochar (lotus leaf) derived carbon nanodots was synthesized through hydrothermal carbonization. The synthesized hollow spherical biochar was engineered via functionalization by grafting –SO3H active sites. The attained catalyst was broadly analyzed by XRD, FTIR, TGA, BET, SEM–EDX, TEM, and XPS analysis after which it was applied for the acetalization reaction of crude glycerol (a biodiesel by-product) to form solketal, a potential fuel additive to valorize the large waste stream generated from biodiesel industry. Employing the RSM-CCD methodology, the experimental matrix was executed, and subsequent data were scrutinized through multiple regressions to model a quadratic equation. Under specific reaction parameters—a reaction duration of 14 min, a molar ratio of 7.5:1, and a catalyst loading of 5.7 wt.%, maximum solketal yield (95.7%) was attained through the ultrasonication method. Finally, to conclude, life cycle cost analysis (LCCA) for solketal production was studied here which determined the overall cost of solketal production per kilogram to be 0.719 USD ($), indicating high commercial applicability. [ABSTRACT FROM AUTHOR]

Different approaches continue to be used to evaluate the environmental and financial impacts of road pavements throughout their life cycle. This paper aims to provide a methodological review of published studies of asphalt pavement Life Cycle Assessment (LCA) and Life Cycle Cost Analysis (LCCA) and make recommendations for future studies. The results indicate that LCA studies limitations are related to functional units (FUs), chosen life cycle phases, maintenance schedules decision, and uncertainty. In comparison, the use of LCCA is limited to assessing maintenance strategies, is largely focused on agency cost, and usually ignores the possibility of current or future uncertainty. Accordingly, it is recommended to incorporate both LCA and LCCA, define a standard set of FUs, include the complete life cycle (including for new materials), consider pavement performance predictions in determining realistic maintenance schedules, include both short- and long-term costs and environmental impacts, and emphasise on probabilistic analysis of uncertainty. [ABSTRACT FROM AUTHOR]

Due to the high cost and complex challenges faced by offshore wind power transmission, economic research into offshore wind power transmission can provide a scientific basis for optimal decision-making on offshore wind power projects. Based on the analysis of the topology structure and characteristics of typical wind power transmission schemes, this paper compares the economic benefits of five different transmission schemes with a 3.6 GW sizeable onshore wind farm as the primary case. Research includes traditional high voltage alternating current (HVAC), voltage source converter high voltage direct current transmission (VSC-HVDC), a fractional frequency transmission system (FFTS), and two hybrid DC (MMC-LCC and DR-MMC) transmission scenarios. The entire life cycle cost analysis model (LCCA) is employed to thoroughly assess the cumulative impact of initial investment costs, operational expenses, and eventual scrap costs on top of the overall transmission scheme's total cost. This comprehensive evaluation ensures a nuanced understanding of the financial implications across the project's entire lifespan. In this example, HVAC has an economic advantage over VSC-HVDC in the transmission distance range of 78 km, and the financial range of a FFTS is 78–117 km. DR-MMC is better than the flexible DC delivery scheme in terms of transmission capacity, scalability, and offshore working platform construction costs in the DC delivery scheme. Therefore, the hybrid DC delivery scheme of offshore wind power composed of multi-type converters has excellent application prospects. [ABSTRACT FROM AUTHOR]

Line planning and timetabling play important roles in the design of urban rail transportation services. Due to the complexity of the integrated optimization of entire transportation plans, previous studies have generally considered line planning and timetabling design independently, which cannot ensure the global optimality of transportation services. In this study, the integrated design problem of line planning and timetabling was characterized as an equilibrium space–time network design problem and solved with a bi-objective nonlinear integer programming model. The model, in which train overtaking and passenger path choice behavior were considered, adjusted the network topology and link attributes (time and capacity) of the travel space–time network by optimizing the train service frequency, operation zone, stopping pattern, train formation, and train order to minimize the system life cycle cost and total passenger travel time perception. An algorithm was constructed using the non-dominated sorting genetic algorithm II combined with the self-adaptive gradient projection algorithm to solve the model. A real-world case was considered to evaluate the effectiveness of the proposed model and algorithm. The results showed that the model not only performed well in the trade-off between system cost and passenger travel efficiency, but it could also reduce the imbalance of train and station loads. Pareto front analysis of the model with different parameters showed that more types of trains did not correlate with a better performance, some line-planning strategies had a combination effect, and multi-strategy line planning was more suitable for scenarios with a high imbalance in the temporal and spatial distributions of passenger flow. [ABSTRACT FROM AUTHOR]

This study presents a comprehensive Life Cycle Cost Assessment (LCCA) of geothermal-assisted hydrogen liquefaction, explicitly focusing on the Afyon Geothermal Power Plant (AGPP) as a case study. The study evaluates the economic viability and sustainability of integrating geothermal energy into hydrogen liquefaction. The results of the LCCA contribute to the ongoing discourse on sustainable energy solutions, offering a nuanced understanding of the economic considerations associated with geothermal-assisted hydrogen liquefaction. The study serves as a model for assessing the economic feasibility of similar systems, fostering informed decision-making in the pursuit of cleaner and more economically sustainable energy pathways. This study has conducted a technical and economic investigation of liquid hydrogen production using geothermal heat and electricity effects. Geothermal water pre-cools the hydrogen by providing heat to the absorption system. Then, the electricity generated in the geothermal plant is used to work in the liquefaction cycle. The generated electricity is used to liquefy hydrogen in the liquefaction cycle. The capacity of the electricity generated from the AGPP produced here is 2621 kW. The proposed system can be achieved by pre-cooling unit H 2 up to −30 °C at 120 °C and 150 kg/s geothermal source. In the liquefaction cycle, 0.84 kg/s H 2 can be liquefied. As a result, the total energy efficiency of the proposed system can be calculated as 32.4% and exergy efficiency as 15.4%. The system's net present value (NPV) was calculated as 65,320,000 $. When life cycle cost analysis was performed using the levelized annual cost (LAC) method, the project's levelized cost was calculated as 7,673,000 $/yr. The unit cost of the liquid hydrogen produced is 1.252 $/kg. This system's discounted payback period (N dpp) is calculated as 3.48. Configuration of geothermal assisted hydrogen generation system. [Display omitted] • A techno-economic evaluation of a hydrogen liquefaction system is introduced. • The Life Cycle Cost Assessment of liquefied hydrogen is conducted. • Using geothermal water in an absorption system, H 2 gas can be pre-cooled to −30 °C. • In the liquefaction cycle, using geothermal energy, 0.84 kg/h H 2 can be liquefied. • Liquefied hydrogen market cost and system payback period are calculated as 1.252 $/kg and 3.48 years, respectively. [ABSTRACT FROM AUTHOR]

Commercial Buildings release large volumes of greenhouse gases, expediting global warming. The commercial building industry accounts for 37% of global CO2 emissions. Geothermal energy technologies are an intriguing solution that provides a low-impact, emission-free, and cost-effective thermal fuel source for baseload energy production. Geothermal energy systems offer a potential solution to dramatically halt global warming and facilitate the transition to a carbon-neutral civilization. This study develops a framework for assessing the geothermal power capabilities of innovative house and district heating systems. The energy requirements are first assessed, and then the spatial evaluation of district heating infrastructure is carried out using a Python-based program. Economic comparisons between geothermal energy and fossil fuels are made using LCC analysis. Environmental impacts are measured by Life Cycle Analysis (LCA). This study compares geothermal energy to fossil fuels, and the LCA results show that geothermal energy has a low environmental impact. With a Net Present Value (NPV) of 34.81 USD, it displays economic viability as well as a satisfactory financial return. The study's findings show that geothermal energy has the ability to compete with fossil fuels in commercial heating applications while still being environmentally beneficial. [ABSTRACT FROM AUTHOR]

Abstract Bridge components are subject to both structural loads and environmental stressors, rendering them susceptible to accelerated deterioration and potential collapse in the absence of effective maintenance and rehabilitation strategies. Moreover, the phenomenon of wet-dry cycling, coupled with elevated chloride concentrations prevalent in coastal regions, further expedites the degradation process of bridges, thereby escalating maintenance frequency and repair costs. In response to this challenge, the integration of innovative materials such as Ultra High-Performance Concrete (UHPC) is being explored for the development and implementation of maintenance and rehabilitation strategies. This study presents a comparative analysis between conventional methods and UHPC applications for bridge repairs, utilizing Life Cycle Cost Analysis (LCCA) to encompass both agency and user costs, and applies Monte Carlo simulation to account for the variability of the modeling factors. A practical case study illustrates the applicability of the LCCA methodology, revealing that the utilization of UHPC contributes to a reduction in the total life cycle cost for bridge maintenance and rehabilitation. Life expectancy, Average Daily Traffic (ADT), and the duration of construction activities during rehabilitation emerge as the most influential factors affecting life cycle costs. The main contributions of the study are the development of the life-expectancy model and step-by-step Life-Cycle Cost Analysis (LCCA) methodology. Findings from this study aim to identify cost-effective retrofitting techniques for maintaining bridges in a “State of Good Repair.”

The increasing demand for sustainable air mobility has led to the development of innovative aircraft designs, necessitating a balance between environmental responsibility and profitability. However, despite technological advancements, there is still limited understanding of the maintenance implications for hydrogen systems in aviation. The aim of this study is to estimate the maintenance costs of replacing the hydrogen storage system in an aircraft as part of its life cycle costs. To achieve this, we compared conventional and hydrogen-powered aircraft. As there is insufficient data for new aircraft concepts, typical probabilistic methods are not applicable. However, by combining global sensitivity analysis with Dempster–Shafer Theory of Evidence and discrete event simulation, it is possible to identify key uncertainties that impact maintenance costs and economic efficiency. This innovative framework offers an early estimate of maintenance costs under uncertainty, enhancing understanding and assisting in decision-making when integrating hydrogen storage systems and new aviation technologies. • Examining hydrogen storage exchange necessity in an aircraft's life cycle. • Pioneering use of evidence theory and global sensitivity analysis amid data scarcity. • Identifying maintenance impact on hydrogen aircraft life cycle costs. • Uncertainties in maintenance events have a high economic impact. [ABSTRACT FROM AUTHOR]

A Life Cycle Assessment (LCA) quantifies the environmental impacts during the life of a product from cradle to grave. It evaluates energy use, material flow, and emissions at each stage of life. This report addresses the challenges and potential solutions related to the surge in electric vehicle (EV) batteries in the United States amidst the EV market's exponential growth. It focuses on the environmental and economic implications of disposal as well as the recycling of lithium-ion batteries (LIBs). With millions of EVs sold in the past decade, this research highlights the necessity of efficient recycling methods to mitigate environmental damage from battery production and disposal. Utilizing a Life Cycle Assessment (LCA) and Life Cycle Cost Assessment (LCCA), this research compares emissions and costs between new and recycled batteries by employing software tools such as SimaPro V7 and GREET V2. The findings indicate that recycling batteries produces a significantly lower environmental impact than manufacturing new units from new materials and is economically viable as well. This research also emphasizes the importance of preparing for the upcoming influx of used EV batteries and provides suggestions for future research to optimize the disposal and recycling of EV batteries. [ABSTRACT FROM AUTHOR]

This study examines the strategic use of life cycle cost analyses (LCCAs) in the management and conservation of heritage sites, emphasizing the need for comprehensive financial planning. With an increasing number of heritage sites showing signs of deterioration, our aim was to improve the sustainability and effectiveness of restoration practices. We used dynamic life cycle costing methods and developed the MONUREV software V2 to simulate different restoration scenarios, providing accurate, data-driven projections for maintaining structural, functional and aesthetic integrity. The field research involved testing these methods through case studies of heritage buildings in the Czech Republic, focusing on holistic cost management from initial analysis to practical application. The results showed that LCC analysis can significantly assist in making informed decisions, balancing economic and cultural values, and ensuring long-term conservation outcomes. This study concludes that the integration of a detailed LCC analysis into heritage conservation strategies represents a methodological advance that can significantly improve the economic and operational planning of the maintenance of heritage buildings, thereby ensuring their preservation for future generations. [ABSTRACT FROM AUTHOR]

This study conducts a comprehensive life cycle cost analysis (LCC) of green retrofitting in mosque buildings, assessing its financial feasibility and performance. The research involves a risk assessment of three crucial stages: pre-, construction, and post-construction. A Likert scale is employed for the validation process based on responses from 51 experts involved in green building retrofit projects. Results indicate that the highest risk occurs during construction, impacting investment performance. Sensitivity analysis reveals the potential longevity of investments, with pre-construction risks affecting the Net Present Value (NPV) in the 18th year and post-construction risks proving feasible by the 17th year. The study introduces benchmarks such as NPV, Internal Rate of Return (IRR), Benefit-Cost Ratio (BCR), and Break Even Point (BEP) for investment evaluation. The financial feasibility of green retrofit items, including solar panels and energy-efficient utilities, is confirmed with an NPV of IDR 140,797,698, IRR of 10.26%, and BCR of 2.21, with feasibility realized in the 17th year. Risk visualization through a Tornado Chart emphasizes the significance of each risk stage on NPV values. In conclusion, the study recommends broader case studies involving multiple certified green mosques for more accurate risk identification. This research provides valuable insights for informed investment decisions in mosque building green items, emphasizing the importance of risk management for long-term sustainability. [ABSTRACT FROM AUTHOR]

Bridge components are subject to both structural loads and environmental stressors, rendering them susceptible to accelerated deterioration and potential collapse in the absence of effective maintenance and rehabilitation strategies. Moreover, the phenomenon of wet-dry cycling, coupled with elevated chloride concentrations prevalent in coastal regions, further expedites the degradation process of bridges, thereby escalating maintenance frequency and repair costs. In response to this challenge, the integration of innovative materials such as Ultra High-Performance Concrete (UHPC) is being explored for the development and implementation of maintenance and rehabilitation strategies. This study presents a comparative analysis between conventional methods and UHPC applications for bridge repairs, utilizing Life Cycle Cost Analysis (LCCA) to encompass both agency and user costs, and applies Monte Carlo simulation to account for the variability of the modeling factors. A practical case study illustrates the applicability of the LCCA methodology, revealing that the utilization of UHPC contributes to a reduction in the total life cycle cost for bridge maintenance and rehabilitation. Life expectancy, Average Daily Traffic (ADT), and the duration of construction activities during rehabilitation emerge as the most influential factors affecting life cycle costs. The main contributions of the study are the development of the life-expectancy model and step-by-step Life-Cycle Cost Analysis (LCCA) methodology. Findings from this study aim to identify cost-effective retrofitting techniques for maintaining bridges in a "State of Good Repair." [ABSTRACT FROM AUTHOR]

This paper aims to investigate potential strategies to reduce energy consumption and environmental impacts of a recently converted rural complex into an agri-spa in a high environmental value area within the province of Viterbo (Italy). Actual operational data on appliances, climate, and energy consumption are employed for the energy audit. While this analysis generally provides energy-saving solutions, such options are not examined for their life cycle environmental impacts. The current article is based on the experimentation of a consolidated methodological approach in the scientific literature, integrating the energy audit, life cycle assessment (LCA), and economic analysis (Life Cycle Cost) to assess a series of energy-efficiency measures designed for the new wellness centre function. The combined use of these well-established procedures provides a comprehensive assessment of intervention scenarios for a particularly energy-intensive type of case study, not yet widely documented in the literature. The results reveal that energy consumption related to heating/cooling is marginal compared to the actual electrical consumption in the specific case study. Therefore, the most efficient scenarios involve installing photovoltaic systems and replacing gas boilers with high-efficiency heat pumps, especially with economically advantageous insulation. This leads to a 51% reduction in energy consumption and an 81% decrease in heating, DHW, and electricity costs. [ABSTRACT FROM AUTHOR]

Over the last decade, restructuring of railway systems has resulted in infrastructure management assets demanding increased performance and reliability while adopting budget limits and reduced time available for maintenance. In fact, the current routine and major programmed maintenances are such capital-intensive activities that transport operating companies always attempt to optimise the operational procedures and related assets' performances towards minimising the costs. Characteristically, the use of macro synthetic fibre reinforcement is proposed to improve the structural performances and service life of the sleeper component. Accordingly, this study addresses the economic feasibility of implementing macro synthetic fibre reinforced concrete (MSFRC) as an alternative material for railway sleeper applications. Through a life cycle costing (LCC) approach, the study evaluates the impact of different asset phases such as acquisition, operation and maintenance, and end-of-life towards a cost comparison of MSFRC with conventional sleeper materials. Hence, the most financially viable option is identified, although key economic parameters are varied to simulate future market values. [ABSTRACT FROM AUTHOR]

Currently, due to the insufficient resources of renewable natural gas, the development of renewable pathways to integrate into the natural gas-industry portfolio can reduce many concerns about the reserves depletion and the environmental crises. In the present article a structure-oriented framework for gas networks is developed to compare and prioritize different investment scenarios for renewable natural gas production projects. In this regard, different pathways to produce renewable natural gas through the waste-to-natural gas process were discussed and compared based on different waste feedstocks. To discuss and compare different pathways, a decision-making structure and framework under life cycle cost analysis (LCCA) and life cycle environmental analysis (LCEA) is employed to choose the appropriate pathway for the waste-to-natural gas process. The optimal pathway is identified through different multi-variable decision-making scenarios (under different geographical conditions, access to different feedstocks, and different interests of stakeholders). From the outcomes, under the neutral and Pro-economic scenarios, the renewable natural gas production pathway driven by landfill gas integrated with the pressure swing adsorption- biogas upgrading unit is the optimal and desirable option. While under an Eco-friendly scenario, the pathway driven by animal manure integrated with the pressure swing adsorption-upgrading unit is an optimal and desirable pathway. [Display omitted] [ABSTRACT FROM AUTHOR]

This article presents and describes a dataset for the bills of materials for the buildings constructed with mass timber (MT), structural steel (SS), and reinforced concrete (RC), which are generated using Athena's Impact Estimator for Buildings (IE4B) software to conduct a whole building life-cycle assessment (WBLCA). These data are associated with the research article Environmental Impact Assessment of Mass Timber, Structural Steel, and Reinforced Concrete Buildings Based on the 2021 International Building Code Provisions [1]. This dataset was utilized to estimate their environmental impacts but can be used to estimate the costs of buildings constructed with MT, SS, and RC building materials. These data could be replicated using the same layout, system boundaries, reference study period (RSP), and building assemblies’ information as used in the published work [1]. This dataset is related to conceptual design of a building with 11 apartment units per floor. However, a detailed design that includes the analysis of interior architectural finishes such as internal partitions within the units, kitchen and washroom fixtures, internal doors, flooring, and so on, could be developed and analyzed to obtain a more comprehensive estimates of life cycle assessment. This dataset was originally developed to compare the environmental impacts of structural materials selection for three common framing typologies.

The adoption of sustainable building policies and the society’s increasing emphasis on sustainability underscore the urgent need to evaluate the environmental and economic impact of construction materials. This study examines the effects of incorporating polyurethane foam waste into gypsum-based ceiling tiles. It compares its economic performance and eco-efficiency with conventional alternatives. Methodologically, Life Cycle Cost Analysis (LCCA) quantifies total life cycle costs, followed by Eco-Efficiency Assessment (EE), considering results from both Life Cycle Assessment (LCA) and LCCA. Our findings reveal a compelling 5.91% cost advantage for the novel precast, driven by enhanced production capacity resulting from shorter drying times. The economic benefits of this approach are underscored by a detailed breakdown of cost savings in production phases. Furthermore, the EE remarks a substantial 7.5% boost, emphasizing the positive environmental impact achieved through reduced resource consumption and lower emissions combined with lower life-cycle costs. These results highlight the economic viability and eco-efficiency of polymeric waste-integrated gypsum ceiling tiles for environmental sustainability. The specific percentage improvements in cost and eco-efficiency provide a quantitative basis for understanding the advantages of adopting these innovative materials.

Climate change and urbanization have led to an increase in the amount of water flowing into traditional drainage systems, which results in frequent urban flooding. Low–Impact Development (LID) facilities, with their distributed feature, are one of the important means to mitigate flooding and have been widely used. In this paper, based on integrated catchment management (ICM), we compare the abatement of runoff, flooding, and ponding under two durations of rainfall and eight different return periods with runoff as the control objective (RACO) and flooding as the control objective (FACO) for the deployment of LID facilities. The waterlogged area of FACO is higher by a range of 92.462 m2 to 24,124.39 m2 compared to RACO. Both percentage reduction of overflow volume and runoff volume tend to decrease gradually with the increase in the return period. For the percentage reduction of runoff volume per unit area, sometimes RACO is greater than FACO, and sometimes vice versa, while for the percentage reduction of overflow volume per unit area, the range where FACO exceeds RACO is between 0.29 to 10.95 (%/ha). The cost of FACO has decreased by 4.94% to 46.20% compared to RACO. This shows that FACO's LID deployment method can fully utilize the capacity of LID facilities to mitigate inundation, reducing the cost of LID facilities to a certain extent. [ABSTRACT FROM AUTHOR]

Road infrastructure serves as a foundational driver of a nation's economic and cultural growth. Incorporating life cycle cost analysis (LCCA), as well as considerations of availability and environmental impact, enables policymakers to make strategic decisions that not only enhance fiscal efficiency but also support sustainable progress. This paper centers on an in-depth examination of two prevalent pavement technologies: continuously reinforced concrete pavements (CRCP) and jointed plain concrete pavements (JPCP). It specifically delineates the application of these methods to a hypothetical one-kilometer motorway construction in Germany. Employing LCCA for concrete pavements, the paper evaluates long-term fiscal prudence among alternative investment opportunities, factoring in resource utilization—both materials and machinery—and long-term care and upkeep obligations over the pavements' operational lifespans. The analysis extends to appraise agency expenditures associated with the pair of pavement strategies and estimates the concomitant delay durations and costs relevant to the exemplar project. Central to this research is the investigation of road availability and its quantifiable influence on traffic efficacy, parsing through metrics such as the tally of days roads are out of service and the subsequent repercussions on vehicular flow. The investigation also proposes strategies for the reduction of embodied carbon in CRCP and JPCP systems. While accounting for variances in functional performance and vehicular comfort levels, this study contributes scientifically by tackling pragmatic engineering dilemmas involved in pavement selection, with a spotlight on minimizing costs, curtailing traffic interruptions, and mitigating ecological impacts for the duration of the pavement's life cycle. [ABSTRACT FROM AUTHOR]

Optimizing the multilayer thermal insulation of pipelines transporting liquids and gases at higher than ambient temperatures is crucial for heat energy conservation and cost optimization. This study utilizes a multi-objective genetic algorithm to optimize the multilayer thermal insulation thickness around a pipe carrying fluid to minimize heat loss and associated costs. The model adopted mathematical associations between design variables and the overall installation cost of layers over a pipe from the available literature. The proposed model considered one or more insulation layers of rock wool and calcium silicate to oil pipelines containing steam, furfural, reduced crude or 300-distillate oil. All calculations considered fixed-charge rates as a fraction of 1 or 0.15. The results were compared with standard values and those predicted by other researchers in the literature. For the steam line, the standard insulation thickness was 50 mm, jumping to 327 mm for rock wool and 232 mm for calcium silicate. However, it decreased to 38 mm for double-layer calcium silicate and 138 mm for double-layer rock wool. For furfural, the insulation thickness was 40 mm, which rose to 159 mm for rock wool and 112 mm for calcium silicate. In general, for all four cases, the results show that using normal insulation thickness is inadequate and not economical. For example, for 300-distillate oil, the present practice puts the cost function at 54 USD/m, which drops to 20 USD/m for rock wool and 24 USD/m each for single-layer silicate and double-layer insulation. This amounts to almost 60% cost savings. Similar trends are observed for the other three cases. This model can provide up to 60% savings in cost and a 92% reduction in heat loss at optimum insulation thickness compared to other models. [ABSTRACT FROM AUTHOR]

This study verified the technological and economic feasibility of converting urban air mobility (UAM) to a fuel cell–battery hybrid propulsion system from an existing battery–only propulsion system. The battery–fuel cell hybrid propulsion UAM was conceptually designed through reverse engineering and redesigned of the existing battery–only propulsion UAM. Under various design conditions, the economic feasibility of the hybrid propulsion system was verified through life cycle cost (LCC) analysis. Hybrid propulsion UAMs designed with appropriate hybridization ratios had 10% lower life cycle costs than battery-only propulsion UAMs. In particular, this cost–saving effect was more noticeable when UAM's flight distance became longer. The life cycle cost increased proportionally as the number of UAM passengers increased, but was relatively unrelated to energy storage technology improvements. Considering the current electricity and hydrogen price changes, the economic feasibility of fuel cell–battery hybrid UAM is expected to continue to improve in the future compared to batteries alone. • The technical and economic feasibility of the fuel cell-battery hybrid propulsion UAM was verified. • The fuel cell-battery hybrid propulsion UAM was conceptually designed through reverse engineering technology. • A properly designed hybrid propulsion UAM had a 10% lower life cycle cost than a battery-only propulsion UAM. • Considering energy price trends, the economics of hybrid UAM are expected to continue to improve. [ABSTRACT FROM AUTHOR]

1960s Europe saw a large number of residential neighborhoods built to house those migrating from the countryside. Today, more than 50 years later, these neighborhoods suffer high levels of functional, social, and technical obsolescence. In response to this, the University of Seville developed the Aura Strategy as an intervention methodology to find global solutions to issues in outdated neighborhoods. To provide visibility to this aspect of the Aura Strategy, the retrofit proposal presented in this article provides a solution to improve the roofing of buildings in a case study neighborhood (Polígono de San Pablo, Seville) and an analysis of the results in terms of energy and financial savings for local residents. The results show that for a population of roughly 18,000 (in 2018), net savings, including energy and retrofitting costs, ranging from nearly € 6.5 to over € 8.6 million can be made over the 20-year life-cycle span. Likewise, the results obtained on the reduction of thermal loads indicate a 72% decrease in energy consumption, equivalent to a saving of close to 4500 tons of greenhouse gas emissions for the district and the entire life-cycle time period, with the consequent benefits on the impact on air quality and the fight against climate change. [ABSTRACT FROM AUTHOR]

Owing to the unavailability of electricity in many remote areas in Peninsular and East Malaysia, these areas do not have access to telephone signals. In remote areas, a diesel generator is used as the power source for the telecommunications base station. Hence, the continuous supply of diesel (which is a fossil fuel) is necessary in these remote areas. In this study, an attempt is made to assess the potential of replacing diesel-generated electricity with wind energy, which is renewable energy. Life cycle cost analysis is carried out, and the payback period of a wind energy system is determined for a remote telecommunications base station in Malaysia. The load characteristics and wind data are obtained from the Mersing Meteorological Station, Malaysia, and it was found that the annual load and base load are 12 kW. Hence, a 12-kW wind turbine is selected for the life cycle cost analysis at the site. The results show that the total specific cost of the 12-kW wind turbine is MYR 0.27/kWh based on a discount rate of 5% and electricity tariff in Malaysia of MYR 0.28/kWh. The payback period and discounted payback period of the 12-kW wind turbine are estimated to be 11.8 and 18.2 yr, respectively. Based on the load characteristics in Mersing, Malaysia, the 12-kW wind turbine is economically viable for the remote telecommunications base station. Nonetheless, the 12-kW wind turbine is not financially feasible because the simple payback period is greater than 1/3 of the wind turbine's lifetime, which is 20 years. The 12-kW wind turbine, on the other hand, is suitable for use as a remote telecommunications base station.

Line planning and timetabling play important roles in the design of urban rail transportation services. Due to the complexity of the integrated optimization of entire transportation plans, previous studies have generally considered line planning and timetabling design independently, which cannot ensure the global optimality of transportation services. In this study, the integrated design problem of line planning and timetabling was characterized as an equilibrium space–time network design problem and solved with a bi-objective nonlinear integer programming model. The model, in which train overtaking and passenger path choice behavior were considered, adjusted the network topology and link attributes (time and capacity) of the travel space–time network by optimizing the train service frequency, operation zone, stopping pattern, train formation, and train order to minimize the system life cycle cost and total passenger travel time perception. An algorithm was constructed using the non-dominated sorting genetic algorithm II combined with the self-adaptive gradient projection algorithm to solve the model. A real-world case was considered to evaluate the effectiveness of the proposed model and algorithm. The results showed that the model not only performed well in the trade-off between system cost and passenger travel efficiency, but it could also reduce the imbalance of train and station loads. Pareto front analysis of the model with different parameters showed that more types of trains did not correlate with a better performance, some line-planning strategies had a combination effect, and multi-strategy line planning was more suitable for scenarios with a high imbalance in the temporal and spatial distributions of passenger flow.

This paper focuses on quantifying the economic and financial viability of NB-IoT and LoRaWAN technologies, two low-power wide-area network (LPWAN) technologies with unique characteristics that make them suitable for IoT applications. The purpose of this study is to propose a “pragmatic” artifact for performing life cycle cost analysis and demonstrate its application to these technologies. The methodology uses pragmatic computational tools to facilitate the analysis and considers all relevant economic and financial factors, such as operating costs, equipment costs, and revenue potential. The main finding of this study is that Narrow Band-Internet of Things (NB-IoT) and Long Range Wide Area Network (LoRaWAN) technologies have different cost structures and revenue potentials, which may affect their economic and financial viability for different IoT applications. Ultimately, the study concludes that a comprehensive life cycle cost analysis is critical to making informed decisions about technology adoption, and that the proposed methodology can be applied to other IoT technologies to gain insight into their economic and financial viability.

The global excessive demand for concrete has resulted in a significant depletion of concrete natural resources and substantial release of carbon emissions in the environment. To tackle such challenges, treated wastewater (TWW), recycled concrete aggregates (RCA), and fly ash (FA) have recently been proposed as sustainable concrete constituents. From a management perspective, it is necessary to evaluate the cost-saving potential of incorporating TWW, RCA, and FA simultaneously in concrete applications. Accordingly, this study conducted a life cycle cost analysis over 60 years on 12 multi-story buildings with TWW, RCA, and FA. Various parameters were investigated, including the number of floors (20–70 floors), discount rate (0–10%), RCA-to-natural aggregate price ratio (50–200%), and construction-to-material price ratio (50–250%). Test results highlighted that buildings incorporating TWW, RCA, and FA showed 60.18% and 19.21% lower maintenance and life cycle costs compared to conventional buildings, respectively. Furthermore, the study showed that the highest cost savings are achieved with a discount rate of 2% or less. The achieved cost saving reveals the importance of utilizing eco-friendly alternatives to natural concrete ingredients. On the other hand, the number of floors, RCA-to-natural aggregate price ratio, and construction-to-material price ratio have negligible effects on the life cycle cost of the buildings.

This study investigated the applicability of a tracking photovoltaic (PV) system installed in the roof area of a commercial building. Because PVWatts is the only PV module with a tracking feature in EnergyPlus, its electricity generation was validated through comparisons with detailed PV modules in EnergyPlus. The tracking PV system generated 26.8–35.5% more electricity annually than a fixed system in the climate of Incheon (S. Korea). The load coverage analysis of the tracking PV system was conducted with the reference commercial building model in EnergyPlus. Approximately 14% of the total building electric demand, including heating, ventilation, and air-conditioning; lighting; and equipment, was met by one PV array. Finally, the life cycle cost analysis of the tracking PV system was conducted by considering the net present value, which includes the initial installation and operation costs. The initial investment was returned after approximately 8 years, assuming between two and six tracking PV arrays were installed. Moreover, up to 26.8% cost savings were achieved in 15 years compared to the case without any PV arrays. [ABSTRACT FROM AUTHOR]

All the modern gadgets and space conditioning in buildings consume lots of energy. Energy consumption can be optimized using Composite Insulation External Walls (CIEW) built from mortar plaster and structural and insulation layers. This study aimed to improve the overall performance of CIEW by optimizing the structural and insulation layer thickness. The objective was to minimize the Life Cycle Cost (LCC) and maximize the Life Cycle Savings (LCS) of CIEW. The nonlinear Least Squares Estimation (LSE) optimization technique for optimizing LCC and LCS of CIEW was used in the study. The study considered three insulation materials—Extruded Polystyrene (XPS), Rock Wool (RW), and Glass Wool (GW)—across three heat sources, including Circulating Fluidized Bed (CFB), Grate-Fired Boiler (GFB), and Air-Source Heat Pump (ASHP). The Life Cycle Cost Analysis (LCCA) methodology suggested by Huang using a traditional optimization technique was used as a basis for mathematical formulations and result comparison. The payback period of CIEW with optimal structural and insulation layer thickness was computed. The findings revealed that applying the LSE method enabled greater economic efficiency than the LCCA method, with an up to 9.12% increase in LCS value and an up to 7.41% decrease in LCC value. The research also revealed significant correlations between insulation and structural layer thicknesses and economic parameters. [ABSTRACT FROM AUTHOR]

Construction industry projects play a significant role in the sustainable economic growth of all other industries. To achieve a sustainable economy, the future associated costs act as a barrier that must be addressed in the initial stages of a construction project. To evaluate the future costs, Life Cycle Cost Analysis (LCCA) is found to be an effective technique that determines the present worth of future costs. This study focuses on reviewing the conducted research in the field of optimising cost during the project life cycle via LCCA to sustain economic sustainability and associating the environmental and social cost factors to enhance sustainability. A systematic literature review strategy is developed to extract relevant literature from Scopus, Web of Science, Science Direct, Emerald and American Society of Civil Engineering from the year 2009 to 2020. Adopting the PRISMA statement, a total of 83 articles are reviewed systematically in detail. Many construction sections are explored with the impact of LCCA on them. The LCCA impact the performance of construction projects during certain practices such as structural designing, energy cost optimisation, building envelope efficiency in energy demand and utilisation optimisation and earthquake engineering. Moreover, this study highlights the influence of LCCA in optimising the environmental impact of a new or existing construction project to avail economic sustainability along with the social and environmental. A conceptual framework has been proposed that shows the influence of LCCA on the construction industry, which directly impacts economic sustainability and indirectly environmental sustainability. [ABSTRACT FROM AUTHOR]

This study aims to present the life cycle cost (LCC) for 1 kg of pear produced using organic technology in Southern Romania. Two principal stages were depicted: production stage costs (PC) and Transport costs (TC). For each stage, investment and operational costs were determined. Pear orchard establishment (POE), the first I-III years of orchard management (without harvest) (OM.I-III), and IV-XX years of orchard management (OM.IV-XX) were analyzed considering the elemental activities included. Three scenarios were applied for fertilization: (S1) compost produced at the farm level using a composter Oklin GG-50S combined with the one produced on outdoor platform in the farm, mainly from vegetable sources. (S2) compost from the outdoor platform for organic residues, and (S3) acquisition of a commercial organic fertilizer. The total LCC for 1 kg of pear ranged between 0.400 € (S2), 0.481 € (S3), and 0.496 € (S1). Details regarding the LCC components and optimization were presented. [ABSTRACT FROM AUTHOR]

This paper focuses on quantifying the economic and financial viability of NB-IoT and LoRaWAN technologies, two low-power wide-area network (LPWAN) technologies with unique characteristics that make them suitable for IoT applications. The purpose of this study is to propose a "pragmatic" artifact for performing life cycle cost analysis and demonstrate its application to these technologies. The methodology uses pragmatic computational tools to facilitate the analysis and considers all relevant economic and financial factors, such as operating costs, equipment costs, and revenue potential. The main finding of this study is that Narrow Band-Internet of Things (NB-IoT) and Long Range Wide Area Network (LoRaWAN) technologies have different cost structures and revenue potentials, which may affect their economic and financial viability for different IoT applications. Ultimately, the study concludes that a comprehensive life cycle cost analysis is critical to making informed decisions about technology adoption, and that the proposed methodology can be applied to other IoT technologies to gain insight into their economic and financial viability. [ABSTRACT FROM AUTHOR]