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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]

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]

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 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]

The literature statistics unmistakably highlight the critical need to enhance the construction industry's sustainability to lower environmental damage and conserve natural resources. This study aims to evaluate the life cycle performance of mortar by assessing its ecological impacts, economic performance, and social feasibility, alongside a thorough technical performance evaluation. The technical performance evaluation performed through physio-mechanical performance revealed that 20% natural sand replaced by granite cutting waste (GCW) is best suitable for rendering application. The compatibility of GCW as natural sand is advocated by SEM and FTIR analysis. The three pillars of sustainability are evaluated as life cycle environmental impacts assessment (LCIA), life cycle cost analysis (LCCA) and social feasibility assessment (SLCA). For LCIA purposes, nine environmental impact (EI) categories have been studied. For LCCA, raw material procurement, transportation, repair, and maintenance have been utilized to obtain the life cycle costing. Social LCA (SLCA) was performed qualitatively through a five-point Likert scale-based questionnaire survey, and responses from 125 stakeholders were analysed using mean item score (MIS). The finding revealed that for GP20 mortar, all the nine EI categories had shown 10–13% lower environmental impacts and 7.2% lower cost than the GP0 mortar mix. The SLCA, comprising five subcategories, i.e., access to material resources, social acceptance, employment creations, safe and healthy living conditions, and community engagement, has positively impacted society when 20% GCW is utilized in rendering mortar as sand. The consolidated index calculation with higher ECM values for the GP20 mortar mix strongly endorsed a sustainable and viable alternative. [Display omitted] [ABSTRACT FROM AUTHOR]

Biowaste-to-biogas processes have been introduced to design a valuable and green renewable plant to achieve a sustainable society and environment. The biomethane production process through biogas upgrading instead of designing a combined heat and power (CHP) system can be more attractive. This study presents a life cycle analysis (LCA) from both cost and environmental standpoints for four biowaste-to-biogas/biomethane process scenarios. Biogas production is achieved through anaerobic co-digestion of the organic fraction of municipal solid waste (OF-MSW) and secondary sewage sludge (S-SS), incorporating a pre-treatment process based on the dark co-fermentation process (DCFP). Each scenario offers distinct methods for utilizing the hydrogen-rich gas and biogas, with varying degrees of energy recovery and efficiency. Two sensitivity studies were conducted under various utilizations of the recovered biomethane and the anticipated electricity mix. Scenario SC-1 (CHP-from-biogas) was found to be the most co-friendly favorable in eight out of eleven impact categories (under the CML/IA technique). Further, biogas upgrading-integrated options exhibited lower impacts. Replacing biomethane instead of petrol in scenarios with upgraded biogas was identified as the most effective approach against climate change. Financial analysis indicated that all layouts are economically viable, each demonstrating a positive NPV over a 20-year period (up to $11.57 million). • Life cycle analysis for different biowaste-to-biogas/biomethane scenarios. • Anaerobic co-digestion process of MSW organic fraction and secondary sewage sludge. • Different method for utilizing the hydrogen-rich gas stream and biogas. • Biogas upgrading-integrated options exhibited less impact in the respective items. • Economically viable, all option demonstrating a positive NPV over a 20-year period. [ABSTRACT FROM AUTHOR]

[Display omitted] • The study is conducted to supply a multi-zone complex via a renewable energy cycle. • A hybrid PV/T–GSHP system has been opted as the source. • Overall COP of the system for the main scenario of the cycle is 2.866. • Winter holidays raise the COP by 16.85% and reduce the LCC by 3.67%. This paper introduces a novel cycle to supply the demands of a huge case study incorporating eight thermal zones with sports and administrative applications for space heating, space cooling, domestic hot water, and electricity. Choosing this complex is one of the most important innovations of the current study. A combination of photovoltaic/thermals and ground-source heat pumps are connected to the storage tanks, heaters, heat exchangers, and some other elements to provide energy for the mentioned buildings. This cycle is simulated numerically using TRNSYS 16, and the amounts of heating and cooling loads of the buildings are estimated via TRNBuild 3.0. The cycle is then discussed to investigate its capability of supplying the demands over the period of 20 years; reaching the coefficient of performance and life cycle cost of 2.866 and 164,451 €, respectively, with less than 0.03 °C drop in ground temperature at the end of the given period. In addition, as an important novelty, defining a number of scenarios provides a thorough examination of the important parameters of the cycle, including environmental, operational, and economic features under different conditions. This comprehensive analysis shows that adding winter holidays or insulating the walls of the buildings are the best ways of improving the system's performance. Lastly, the operation of the system in Iran is also compared with some other countries; showing that installing this system is not economically suitable in Iran. Portugal with a payback time of 3.84 years is the best country to install the designed cycle. [ABSTRACT FROM AUTHOR]

This paper aims to make recommendations about the convenience of using low-noise pavements to mitigate traffic noise under different traffic and population scenarios. To do so, a life cycle approach has been applied by performing a Life-cycle Assessment (LCA) and Life-cycle Cost Analysis (LCCA). To account for the noise mitigation achieved by the road surfaces, which is the main benefit compared to conventional road surfaces, the damage effect of traffic noise has been incorporated in both analyses. Thus, open source noise emission and propagation modelling and Geographical Information System (GIS) tools have been used to determine the noise level at which residents are exposed. The impact of noise emissions on human health is estimated and expressed in disability-adjusted life years (DALYs) and the related external cost have been calculated by monetarizing the environmental impacts and by integrating them within the cost assessment. The methodology followed allowed the comparison of different scenarios and the results show a huge potential for reducing environmental impacts and costs when using low-noise road surfaces although accurate information about the acoustic aging of the materials is key in order to ensure that benefits are obtained. [Display omitted] • The feasibility of low-noise road surfaces has been evaluated combining LCA and LCCA. • Noise exposure is assessed using open-source GIS and noise modelling tools. • Population and traffic density influence low-noise surfaces viability. • Traffic noise impacts significantly outweigh other LCA/LCCA categories. • Acoustic ageing estimates of low-noise surfaces affect low-noise surfaces viability. [ABSTRACT FROM AUTHOR]

• Climate change accelerates pavement deterioration, increasing maintenance and fuel use. • Significant pavement deterioration is expected to occur in Southeast China. • Preventative maintenance strategies can reduce fuel use, GHG emissions, and costs. Pavements are susceptible to accelerated deterioration due to changing climate conditions, leading to increased maintenance and excess fuel consumption through pavement-vehicle interaction. China's diverse climates raise concerns about the environmental and economic sustainability of flexible pavements amid climate change and the effectiveness of preventative maintenance strategies. This study examines climate change's potential impacts on long-term pavement performance, greenhouse gas (GHG) emissions, and costs, employing the Mechanistic-Empirical Pavement Design Guide method. The calibrated World Bank's Highway Development and Management Model 4 assesses the impacts of surface characteristics on vehicle fuel consumption. Life cycle assessment and life cycle cost analysis quantify GHG emissions and costs. Results reveal significant pavement deterioration in Southeast and Central China. Preventative maintenance strategies reduce fuel consumption, with GHG emissions and cost savings from smoother driving conditions outweighing those from maintenance. These insights stress the importance of proactive maintenance strategies for mitigating climate-induced deterioration and enhancing sustainability. [ABSTRACT FROM AUTHOR]

Oil-Based Drill Cuttings (OBDC) are one of the hazardous wastes of the oil and gas industry. In this study, Reclaimed Asphalt Pavement (RAP), OBDC and Fly Ash (FA) geopolymer were used in Cold Central Plant Recycling (CCPR) mixtures. The dynamic modulus test was used to appraise the viscoelastic properties of CCPR mixtures. The Toxicity Characteristic Leaching Procedure (TCLP) test was also utilized to investigate the long-term contaminants leaching. In addition, a cradle-to-grave Life Cycle Assessment (LCA) and Life Cycle Cost Analysis (LCCA) were conducted to evaluate the potential environmental burdens and economic costs of pavement structures containing CCPR mixtures. Moreover, Multi-Criteria Decision-Making (MCDM) analysis using four different methods was performed to determine the optimal sample. The results revealed that the recycling of OBDC and RAP in stabilized CCPR mixtures with FA geopolymer can improve the viscoelastic properties and prevent the leaching of contaminants from these waste materials. Furthermore, recycling of the mentioned waste materials in CCPR mixtures has caused a significant reduction in global warming, acidification, eutrophication, smog, respiratory effects, Human toxicity, ecotoxicity, and cumulative energy demand up to 41%, 36.6%, 73%, 43%, 47%, 34%, 73%, and 13%, respectively. Additionally, using CCPR mixtures containing the OBCD, RAP, and FA geopolymer in the pavement structure has led to economic benefits of up to 31% compared to the conventional pavement system. [Display omitted] • OBDC and RAP were recycled as alternative aggregates in CCPR mixtures. • Replacing RAP with OBDC enhanced the viscoelastic performance of CCPR mixtures. • Recycling OBDC and RAP in CCPR-stabilized mixtures with geopolymer lowers leaching. • LCA and LCCA reveal benefits from recycling OBDC and RAP compared to landfilling. • MCDM analysis was performed in order to determine the optimal mixture. [ABSTRACT FROM AUTHOR]

• A special rejuvenation strategy of incorporating extra rubber is proposed. • Incorporating extra rubber could better improve the cracking and aging resistances. • The recycling of reclaimed asphalt rubber pavement reduces GHG emission and cost. Asphalt rubber (AR) is a prevailing sustainable paving material, but the recycling of reclaimed asphalt rubber pavement (RARP) faces the lack of proper rejuvenation strategies and the uncertainties in its economic and environmental values. To fill these gaps, this study assesses the comprehensive performance of RARP-included mixtures using different rejuvenation schemes through mechanical tests, life cycle cost analysis (LCCA), and life cycle assessment. The addition of rejuvenators increased the rutting depth of RARP mixture but their effects on the cracking resistance varied from different types of rejuvenators. The supplement of swollen rubber content was more effective in improving the cracking and aging resistances. Recycling 40 % of RARP into new AR mixture can save 24.5 % of greenhouse gas (GHG) emissions and 35 % of cost within the geographic scope of Hong Kong. The use of rejuvenator increased the GHG emission and cost, while incorporating extra rubber could further reduce the cost. [ABSTRACT FROM AUTHOR]

Ground source heat pumps (GSHPs) in tropical regions require a large-scale ground heat exchanger (GHE) owing to the excessive cooling load and high subsurface temperatures, resulting in increased initial costs and greenhouse gas (GHG) emissions in all phases, excluding the operation phase. However, investigations of the compatibility of GSHPs in tropical regions have been limited to evaluations based on energy consumption in the operation phase, leading to a lack of clarity regarding the contribution of increased initial cost and GHG emissions to the environmental compatibility and economic feasibility based on lifecycle aspects. Thus, this study aimed to evaluate the GHG emissions over the entire life cycle and the cost payback time of a 20-kW capacity GSHP in Bangkok, Thailand, designed with a predicted 50-year heat sink temperature. The results confirmed that the required scale of GHEs is twice as large in tropical regions as in mid‒high latitude regions; nevertheless, the energy-saving of the GSHP resulted in an 8.8 % reduction in GHG emissions over the entire life cycle compared to an air source heat pump. However, the capital investment cannot be recovered within the lifetime of the GSHP, requiring incentives and cost reduction due to the growth of the GSHP market. [ABSTRACT FROM AUTHOR]

• Life cycle cost (LCC) analysis of MSW treatment systems was conducted for Mumbai. • Scenario with recycling and landfill was economically preferred than others. • Scenario with recycling, composting and incineration was the most cost-intensive. • Sensitivity analysis was done to measure the impact of crucial factors on net LCC. This study quantifies and compares the cost of municipal solid waste (MSW) management systems under different scenarios using life cycle cost (LCC) analysis approach. LCC analysis was performed for six integrated MSW management scenarios for Mumbai city, India which generates over 9000 metric tonnes of MSW daily and disposes most of it in open dumps. The scenarios are the combinations of recycling, composting, anaerobic digestion, incineration with electricity generation, and landfill with biogas recovery. To perform LCC analysis of scenarios, present worth method was used. The present worth of operations and maintenance (O&M) cost and revenue generated was estimated using a discount rate of 11.25% for a 20-year life span. Results show that the incineration based scenario is the most cost-intensive option with a net LCC of US$38 per tonne of MSW due to the high capital cost involved in case of incineration. While the scenario with a combination of recycling and sanitary landfill was the most economically viable option with a net LCC of US$19 per tonne of MSW due to comparative lower operating cost. The sensitivity analysis shows that the O&M cost was the most sensitive parameter and a change of ±10% and ±20% in O&M cost, the net LCC of scenarios changes in the range of 14–33% and 29–65%, respectively. This study provides an economic comparison of MSW treatment scenarios from a life cycle perspective, which facilitates the decision-making process for improvement in cost estimation and planning of waste management strategies in India. [ABSTRACT FROM AUTHOR]

Climate change impacts such as extreme temperatures, snow and ice, flooding, and sea level rise posed significant threats to railway infrastructure networks. One of the important questions that infrastructure managers need to answer is, "How will maintenance costs be affected due to climate change in different climate change scenarios?" This paper proposes an approach to estimate the implication of climate change on the life cycle cost (LCC) of railways infrastructure assets. The proportional hazard model is employed to capture the dynamic effects of climate change on reliability parameters and LCC of railway assets. A use-case from a railway in North Sweden is analyzed to validate the proposed process using data collected over 18 years. The results have shown that precipitation, temperature, and humidity are significant weather factors in selected use-case. Furthermore, our analyses show that LCC under future climate scenarios will be about 11 % higher than LCC without climate impacts. [ABSTRACT FROM AUTHOR]

Cold-in-place recycling (CIR) is a sustainable road pavement maintenance technology for its on-site operation and complete reuse of reclaimed asphalt pavement. However, its sustainable performance has not been thoroughly investigated. This study aims to systematically assess and compare CIR against three alternative maintenance technologies from technical, cost and environmental perspectives, specially taking into account different numbers of repaired layers. The technical improvement in full-depth loading resistance is evaluated using a newly developed multi-sequenced repeated load (MSRL) test. Environmental impacts are assessed through life cycle assessment (LCA), while cost analysis is conducted using life cycle cost analysis (LCCA), with consistent system boundary applied. Additionally, a nexus analysis is performed using a modified Boston Consulting Group (BCG) matrix to comprehensively examine the sustainable performance of different treatments and further explore the synergies and trade-offs among various assessment aspects. The multi-dimensional sustainable assessment results reveal the influence factors in each perspective. Final BCG matrix shows that CIR can achieve the comparable technical performance to the conventional maintenance treatment, while reducing GHG emissions by 60.8% and cost by 45.8%. The methodology and findings of this study are expected to provide helpful insights for decision-makers in reducing negative impacts and promoting integrated management for sustainability. • CIR achieves comparable tech performance to conventional maintenance, reducing GWP by 60.8% and cost by 45.8%. • Material activities contribute most to GWP (74.1%–89.8%) and cost (69.5%–83.6%). • Pavement condition before maintenance is vital for enhancing rutting resistance during maintenance. • Thickness of new layer impacts construction cost, with potential increase of 30.5%–40.8% for every additional 2 cm thickness. [ABSTRACT FROM AUTHOR]

[Display omitted] • Magnetically separable biomass-derived nanocatalyst for biodiesel production. • RSM-CCD enables efficient optimization of reaction parameters. • A high biodiesel yield of 96.5 % was obtained under microwave irradiation. • Catalyst reusability is displayed up to 6 reaction cycles achieving 80.6 % yield. • According to life cycle cost analysis price of 1 kg of biodiesel is merely $1.05. An active, high surface area, recyclable, magnetic, basic, iron oxide-based nanocatalyst was developed from banana leaves waste and used for microwave-assisted transesterification of soybean oil to biodiesel. According to the Hammett indicator, the catalyst has a high total basicity of 15 < H < 18.4. After optimization through the response surface methodology, the reaction allows 96.5 % biodiesel yield in the presence of 24:1 methanol to soybean oil molar ratio, 6 wt% BLW@Fe 3 O 4 , 0.5 h at 65 °C. The magnetic nature of the catalyst improves reusability for up to 6 cycles. Thermodynamic analyses showed that transesterification of soybean oil to biodiesel is an endothermic reaction. Moreover, the catalyst has the potential to reduce biodiesel production costs by utilizing abundant biomass waste materials. The calculated cost for 1 kg of catalyst is $1.14, while the biodiesel's cost per kg produced in this work is merely $1.05, showing high commercial viability. [ABSTRACT FROM AUTHOR]

This study aims to determine the thermal, acoustic, and hygroscopic properties of materials designed for building thermal insulation. These materials are composed of cardboard reinforced with fibers sourced from date palm trees. The composite formulation involves a mixture of 40% date palm components, including pinnate leaves, clusters, trunk petioles, and palm fibers, along with 60% cellulose-based cardboard waste. Water is used as the binding agent, eliminating the need for additional chemicals or additives. For the assessment, thermal conductivity, thermal diffusivity, normal transmission loss (TL), and the acoustic absorption coefficient were measured using the hot plane method, flash method and acoustic impedance tube, respectively. The results indicate that the developed composites have thermal conductivity values ranging from 0.074 to 0.081 W/m.K for a density ranging from 226.6 to 312.8 kg/m³. Additionally, the sound transmission loss coefficients exceed 5 dB in the frequency range of 500–1400 Hz, and the acoustic absorption coefficient is greater than 0.4 across a wide range of frequencies from low to high frequencies (200 Hz–1400 Hz). Furthermore, after 6 h of water immersion, a minimal capillary water absorption coefficient of 203% is achieved. What sets this study apart is the comprehensive life cycle cost analysis performed, shedding light on the sustainability of these materials. The optimization of insulation thickness was also conducted, determining optimal values based on climate conditions and energy sources. Overall, this innovative approach offers environmentally friendly and sustainable insulation options for the construction industry, integrating thermal and acoustic properties, life cycle cost analysis, and insulation thickness optimization. [Display omitted] • The materials studied are based on cardboard waste and date palm fibers. • The thermal conductivity of materials developed is between 0.074 and 0.081 W/m.K. • The sound absorption coefficient of materials developed is greater than 0.4. • The materials developed help to enhance comfort thermal and reduce energy consumption. • The optimum thickness is determined based on climatic conditions and energy sources. • The materials developed are eco-friendly, and contribute to reducing GHG emissions. [ABSTRACT FROM AUTHOR]

Textile envelope integrated flexible photovoltaic (TE-FPV) systems gain more attentions in recent years because of their lightweight structure and innovative design. Three types of TE-FPV systems are designed as a sunshade for a teaching building in Politecnico di Milano to replace the current PV glazing sunshade. The environmental and economic feasibility of TE-FPV systems is investigated by applying life cycle assessment (LCA) and life cycle cost analysis (LCCA) in a cradle-to-cradle approach. LCA provides carbon footprint of systems to quantify the environmental performance. LCCA study considers the contribution of life cycle cost, building owner income, and social and environmental benefits. The results are compared with the PV glazing sunshade. From the results, all TE-FPV systems can achieve the economic benefits for the whole society while producing renewable and clean energy. Building owner can even earn benefits from the TE-FPV systems in Norway. The proved success of economically feasible TE-FPV systems in Bergen, Norway serves as compelling evidence for the broad applicability of such systems across the most areas within Europe. • The concept of the TE-FPV system is reinforced for the diffusion. • The influence of social and environmental factors on profitability is involved. • The feasibility of perovskite solar cells in the real projects is investigated. • The technical improvement of perovskite solar cells is considered. • TE-FPV systems are feasible for the most areas within Europe. [ABSTRACT FROM AUTHOR]

As the importance of achieving carbon neutrality continues to grow, green hydrogen energy has emerged as a promising solution as a clean and sustainable energy source. One of the environmentally friendly methods of producing hydrogen is through offshore wind energy, which generates no pollutants during the process. While there have been economic analyses conducted on this production process, the subsequent life cycle study of hydrogen transport scenarios is often overlooked. To bridge this gap, this study focuses on conducting a comprehensive life cycle cost analysis of two hydrogen transport scenarios that utilize ammonia as the carrier. The analysis encompasses various aspects, including life cycle cost analysis, net present value, and the calculation of the levelized cost of hydrogen. Comprehensive sensitivity analysis is performed, considering indicators such as boil-off gas leakage rate and annual transportation mass. Furthermore, this study analyzes the operational risk rate and payback period of the two transportation scenarios. The findings reveal that for transportation distances within 100 km, the life cycle construction cost for the pipeline transport scenario amounts to 761 M$, whereas for ship transportation, it is 201 M$. The annual transport mass for the pipeline is estimated to be 12,000 metric tons, while for the ship, it is 8600 metric tons. The levelized cost of hydrogen is calculated to be 14.62 $/kg for pipeline transportation and 15.54 $/kg for ship transportation. Notably, the annual transport mass emerges as a significant factor impacting the levelized cost of hydrogen in both scenarios. Furthermore, by achieving an annual transport mass of 18,000 metric tons, the levelized cost of hydrogen can be reduced to 10.42 $/kg when the transportation distance extends to 450 km. This highlights the importance of considering the annual transport mass to optimize the cost-efficiency of hydrogen transportation. [Display omitted] • Life cycle cost analysis is conducted for ammonia-based hydrogen transport. • Two typical offshore hydrogen transport scenarios are studied comparatively. • Net present value, leveling cost of hydrogen, and contribution rate are considered. • Annual transport mass is a vital factor affecting levelized cost of hydrogen. [ABSTRACT FROM AUTHOR]

Highway pavement construction with recycled solid waste materials had become a sustainable topic of great concern recently, due to the potential environmental and economic benefits behind. This review focused on the emerging Life Cycle Assessment (LCA) and Life Cycle Cost Analysis (LCCA) studies concerning the recycling of solid waste in highway pavement. Firstly, based on the existing studies, the application of most recycled solid waste materials (e.g. recycled asphalt pavement, steel slag and coal fly ash) in highway pavement performed satisfactorily from the environmental and economic perspectives, concretely manifested in the reduction of energy consumption, greenhouse gas emissions, costs and other indicators. However, several factors, such as lengthened transport distance of recycled waste solid materials and potential leaching of heavy metals, might hinder the recycling. Moreover, it was necessary to pay more attention to pavement use phase, allocation procedure and transport distance of recycled solid waste materials, which had significant impacts on LCA result. In terms of existing LCCAs, the importance of analysis period and discount rate was highlighted and the most practical economic indicator was Net Present Value (NPV). For future study, allocation was still an important issue for future LCA studies and further sensitivity analyses could focus on the selection of transport modes (in LCA), analysis periods and discount rates (in LCCA). Meanwhile, future research should emphasis on the recycling of solid waste in pavement maintenance and rehabilitation projects rather than new construction. A multi-criteria assessment integrated LCA and LCCA as well as other considerations (e.g. an advanced risk assessment) was recommended to determine the most sustainable recycling scenarios. [ABSTRACT FROM AUTHOR]

Abstract Photovoltaic (PV) greenhouses generate solar electricity while providing a suitable environment for crop production. Energy and life cycle cost (LCC) analysis were employed to study the potential for installing semi-transparent photovoltaic (STPV) cladding on the roof of a greenhouse that employs supplemental lighting located in Ottawa, Ontario, Canada (45.4°N). The study was conducted using current and future projected (future projection study) values for the efficiency of PV and horticultural lighting technology. The STPV cladding generated solar electricity but also caused internal shading that was counteracted by augmenting supplemental lighting by as much as 84%, which in turn reduced heating energy use by up to 12%. Although STPV cladding increased lighting electricity use, it generated 43.7% of the electricity that was consumed for supplemental lighting in the present study and 107.2% in the future projection study. Therefore, in the future, a STPV roof could potentially displace all the greenhouse's electricity needs for supplemental lighting. Currently, STPV cladding would not an economically attractive investment. However, a nearly 23% reduction in LCC was achieved in the future projection study. STPV will increasingly become a promising cladding alternative for improving energy efficiency and economics of greenhouse operations. Highlights • Greenhouse envelope design was performed using energy and economic analysis. • A semi-transparent photovoltaics (STPV) roof was investigated for Ottawa, Canada. • Up to 23% reduction in life cycle cost was achieved in the future projection study. • In the future, STPV could produce all lighting electricity needed for crop growth. [ABSTRACT FROM AUTHOR]

Life Cycle Assessment (LCA) has been used to assess the environmental implications of emerging technologies in different manufacturing sectors. However, it is challenging to use the traditional LCA method to model the relationships between Life Cycle Inventory (LCI) data and key technical parameters, preventing further analysis for understanding key driving factors and determining priorities for research and technology development. Furthermore, the sensitivity analysis of traditional LCA could be misleading for decision making or strategic planning given that the potential/possibility of improving specific parameters are commonly not taken into consideration. In this work, a novel parametric analysis framework was developed to address the methodological challenge. The modeling framework integrates process-based engineering models with LCA, Life Cycle Cost analysis (LCC), and optimization. The framework is demonstrated through a case study of additive manufacturing (AM). [ABSTRACT FROM AUTHOR]

Emerging rise in power costs and sustainability of the available energy has prompted industries to seek alternative solutions that could address energy consumption as the second highest contributor to business expenditure compared to salaries and rentals. Regrettably, numerous industries are still reluctant to benefit from the opportunities that exist on energy saving and consciousness, due to inadequate knowledge on energy management, resources and tools to monitor the losses. Based on these facts, this paper proposed the Energy Efficiency Analysis Modelling System (EEAMS) as a tool to provide an estimate of energy costs using rail car manufacturing plant load profiles as a case study, to provide consumer-oriented analysis to produce first-cut energy efficient program baseline costs. Furthermore, the exploration of energy efficiency baseline may benefit the life cycle cost of the overall proposed facility through energy efficient means of production, and continuous improvement practises in big data analytics towards reduction of energy costs significantly through integration of energy efficiency software (EES). To achieve this, a bottom-up approach methodology was adopted, using information on energy cost as a baseline to allow centralisation and cloud hosting of data through a web-based interacting energy efficiency sustainability framework platform, to determine the economic impacts of energy measurement and verification on energy consumption and environment. Minimum Efficiency Performance Standards established to provide opportunities for the support of the rail car manufacturing company to prepare themselves for the issuing of certificates for energy management (ISO50001). [ABSTRACT FROM AUTHOR]

Abstract Sustainability is of paramount importance when facing the design of long lasting, maintenance demanding structures. In particular, a sustainable life cycle design for concrete structure exposed to aggressive environments may lead to significant economic savings, and to reduced environmental consequences. The present study evaluates 18 different design alternatives for an existing concrete bridge deck exposed to chlorides, analyzing the economic and environmental impacts associated with each design as a function of the maintenance interval chosen. Results are illustrated in the context of a reliability-based maintenance optimization on both life cycle costs and life cycle environmental impacts. Maintenance optimization results in significant reductions of life cycle impacts if compared to the damage resulting from performing the maintenance actions when the end of the service life of the structure is reached. The use of concrete with 10% silica fume has been shown to be the most effective prevention strategy against corrosion of reinforcement steel in economic terms, reducing the life cycle costs of the original deck design by 76%. From an environmental perspective, maintenance based on the hydrophobic treatment of the concrete deck surface results in the best performance, allowing for a reduction of the impacts associated with the original design by 82.8%. Highlights • Environmental and Economic Life Cycle Assessment of different design strategies for bridge decks in coastal environments. • 18 design alternatives were studied and compared. • Maintenance strategies is optimized for each design following a reliability-based approach. • Maintenance optimization results in significant reductions of life cycle impacts. • Concrete with silica fume and hydrophobic surface treatments perform best in economical and environmental terms. [ABSTRACT FROM AUTHOR]

Abstract Green roofs have become popular in urban areas as a solution to restore green space in cities and mitigate urban problems. In this study, the economic and environmental sustainability of using green roofs for rooftop agriculture (i.e., roof farms) is evaluated and compared with that of using green roofs as extensive gardens of flowers and non-edible plants with low maintenance (i.e., roof gardens) based on these two green roofs that were installed and operated for over five years in a university building in Seoul, Korea. The life cycle cost analysis results show that the total cost of the roof garden is 38.9% lower than the flat roof whereas the total cost of the roof farm is 68.3% higher than the roof garden. The environmental impacts of both the roof garden and farm were 2.4–35 times as high as those of the flat roof. The need to frequently replenish the lightweight soil over its lifetime was the main contributor to both the economic cost and environmental impacts of the roof farm, suggesting a need to develop cost-effective and environmentally benign lightweight soil materials. A survey was also conducted to investigate public preferences and perceptions of these two green roof options. Over 80% of the respondents expressed the necessity for green roofs in urban areas, and 79.3% preferred roof gardens over farms. Our results show that roof farms have several merits in urban areas, especially social benefits, but future research should focus on improving their economic and environmental sustainability. Graphical abstract Image 1 Highlights • Use of green roofs as rooftop farm versus extensive garden is evaluated. • The life cycle cost of roof garden is lower than flat roof, but roof farm was higher. • Lightweight soil is the main economic and environmental contributor of roof farm. • A survey study showed that 79.3% of respondents preferred roof gardens over farms. • Economic and environmental sustainability of roof farms should be further improved. [ABSTRACT FROM AUTHOR]

Global greenhouse gas emissions and medical supply management systems are facing increasing challenges at the social, environmental, and economic levels. This study aims to propose a multi-objective assessment method coupled with life cycle assessment and life cycle cost analysis to evaluate the entire process of medical supply represented by surgical mask from production to recycling into hydrogen from environmental and economic perspectives. Mass and energy flow data are obtained from literature and the hydrogen production process by plasma gasification of surgical mask established using Aspen Plus. The results reveals that the life cycle energy consumption, global warming potential, acidification potential and photochem ozone creation potential in the surgical mask collection, pretreatment, plasma gasification and waste heat recovery stage account for 77.34%, 40.20%, 46.00% and 44.63% of the entire life cycle, respectively. Operating costs have a significant impact and using of fully automatic equipment and improving the energy consumption of plasma torches are critical to reducing system operating costs. A sensitivity analysis of the four modes of hydrogen transport is performed, and the best mode of hydrogen transport is proposed. This study provides basic information reference for the medical product management system. • A model for combing LCA and LCCA to evaluate MSPRH process is proposed. • LCEC and six environmental impact types are selected as LCA evaluation indicators. • Raw material cost and energy cost are the main contributors of life cycle cost. • Effects of hydrogen transportation mode and distance on LCEC and GWP are studied. [ABSTRACT FROM AUTHOR]

[Display omitted] • ZIF-8 MOF-derived CaO/ZnO nanocatalyst used for transesterification of soybean oil. • RSM-CCD enables efficient optimization of reaction parameters. • A high biodiesel yield of 97.4 % was obtained under microwave irradiation. • Catalyst reusability is displayed in up to 5 reaction cycles achieving 87.8 % yield. • According to life cycle cost analysis price of 1 kg of biodiesel is merely $1.11. In this study a novel, high surface area, and recyclable nano-size solid basic catalyst is developed for the first time from ZIF-8 MOF-derived CaO/ZnO for the high-yielding transesterification of soybean oil (SO) to biodiesel with methanol under microwave irradiation. The chemical composition, texture and morphology of the catalyst were comprehensively characterized by FT-IR, SEM-EDS, XRD, TGA, XPS and BET. In addition, 1H NMR analyses were performed to confirm the conversion of soybean oil to biodiesel, whereas, GC–MS spectrum provide information about the chemical composition of the produced biodiesel. Kinetic studies are performed for the optimized catalyst and it follows the pseudo-first-order reaction. Thermodynamic analyses show that the transesterification of soybean oil to biodiesel reaction is endothermic and not spontaneous. By using Response surface methodology (RSM), the optimization of parameters that affect the biodiesel yield is studied. The transformation of 1:20 soybean oil with methanol using CaO/ZnO catalyst (7 wt%) gives 97.4 % biodiesel yield for the transesterification at 90 °C for 50 min. The catalyst shows good reusability after 5 successive cycles demonstrating its industrial-scale applications. According to Life cycle cost analysis (LCCA) the estimated price of 1 kg of biodiesel produced in this work is merely $1.11 showing high commercial applicability. [ABSTRACT FROM AUTHOR]

Green Infrastructure (GI) has become increasingly important in urban stormwater management because of the effects of climate change and urbanization. To mitigate severe urban water-related problems, China is implementing GI at the national scale under its Sponge City Program (SCP). The SCP is currently in a pilot period, however, little attention has been paid to the cost-effectiveness of GI implementation in China. In this study, an evaluation framework based on the Storm Water Management Model (SWMM) and life cycle cost analysis (LCCA) was applied to undertake integrated assessments of the development of GI for flood mitigation, to support robust decision making regarding sponge city construction in urbanized watersheds. A baseline scenario and 15 GI scenarios under six design rainfall events with recurrence intervals ranging from 2–100 years were simulated and assessed. Model simulation results confirmed the effectiveness of GI for flood mitigation. Nevertheless, even under the most beneficial scenario, the results showed the hydrological performance of GI was incapable of eliminating flooding. Analysis indicated the bioretention cell (BC) plus vegetated swale (VS) scenario was the most cost-effective GI option for unit investment under all rainfall events. However, regarding the maximum potential of the implementation areas of all GI scenarios, the porous pavement plus BC + VS strategy was considered most reasonable for the study area. Although the optimal combinations are influenced by uncertainties in both the model and the GI parameters, the main trends and key insights derived remain unaffected; therefore, the conclusions are relevant regarding sponge city construction within the study area. [ABSTRACT FROM AUTHOR]

The building sector is one of the largest consumers of natural resources and energy in the world. Design strategies to improve the energy efficiency can decrease the negative impacts of a building. In order to evaluate and select the most appropriate design strategies for buildings, they should be analysed through a multidisciplinary approach based on sustainable development. The objective of this study is to propose a method that combines adaptive thermal comfort, climate change, life cycle assessment, life cycle cost analysis and multi-criteria decision making to help selecting the best design strategies to improve the sustainability of buildings. The method presented herein is based on a system of indicators that allows a comprehensive evaluation of design strategies. A multi-family social building, located in Milan, northern Italy, was used as a case study considering a 100-year lifespan. Six design strategies were evaluated. The EnergyPlus computer programme was used to estimate the annual energy demand for air-conditioning alone, with and without the design strategies. Three different databases were used to perform the life cycle analysis. For the life cycle cost analysis, the cost of each strategy was estimated based on the pricelist of the Milan Chamber of Commerce ( Camera di Commercio di Milano ). The results show that there will be an average increase of 53% in the cooling energy demand and a decrease of 49% in the heating energy demand in 2080 compared to the consumption in 2017. The design strategy with the highest level of sustainability was a reinforced concrete frame with rectified bricks, followed by a reinforced concrete frame with cellular concrete blocks and by cross-laminated timber (X-Lam) and wood fibre. This research highlighted the need for the use of a multi-criteria method to ensure the right selection of design strategies to obtain more sustainable buildings. [ABSTRACT FROM AUTHOR]

By adopting the concept of modularity, this paper introduced an optimal framework which facilitates life cycle assessment and life cycle cost assessment, thereby supporting rapid and reliable decision-making in the marine industry. The benefits of the proposed framework were discussed through two case studies where the optimal configurations of marine propulsion systems were determined from the economic and environmental perspectives. First, the performance of a short-route ferry using the hybrid system was compared with those of equivalent ships using diesel-electric and diesel-mechanical propulsion systems respectively. Research findings revealed the excellence of the hybrid system in both economic and environmental aspects. Second, the same method was applied to an offshore tug vessel to determine an optimal engine configuration. Results of analysis emphasised that the selection of multiple small-sized engines is more effective than two medium-sized engines. Both studies have proven that the proposed framework would be useful and practical for accelerating the life cycle analysis which allows ship designers and owners to obtain the long-term view of economic and environmental impacts for particular products or systems without demanding process. The paper also opened up the possibility of extending the application of the proposed framework to the areas where proper decision-making is essential but under-used. [ABSTRACT FROM AUTHOR]

South Africa is a semi-arid developing country facing water and energy insecurity. There are colossal challenges in reliably providing these resources amid growing population, increased urbanization and improved living standards causing increased demand for these resources. Development of new supply centralized systems comes at an exorbitant cost, whereas decentralized systems are touted as an attractive alternative. Grey water recycling and rain water harvesting at buildings level is such an alternative that can provide water for non-potable uses. However, there are technological challenges of optimally operating such systems while ensuring efficient use of associated energy. This paper introduces two control strategies; open loop optimal control and closed-loop model predictive control (MPC) strategies aimed at ensuring safe and reliable operation of the grey water recycling and rain water harvesting system while efficiently using associated energy. From the case study, the proposed system with either control strategy can save the cost of water and waste water by up to 32.3% and 29.5% respectively, while leading to 35.7% in energy cost savings and 31.5% in total operational cost savings in a month. Adoption of these systems would have a huge environmental effect in reducing demand for sewerage services, conservation of water hence reducing demand for potable water as well as increasing the energy efficiency. Furthermore, the system would increase the reliability and security of water supply. Despite the benefits, the system does not pay within its lifetime and therefore, government intervention is required so as to make it economically attractive. High cost of implementation coupled with low potable and waste water tariffs harbour adoption of these systems. Appropriate regulations, policies, incentives and public education are necessary to support such novel technologies in ensuring resource conservation, efficiency and security are achieved. [ABSTRACT FROM AUTHOR]

• Methodology to predict the tunnel climate in long railway tunnels. • Energy balances in order to determine the required cooling effort. • 1D and 3D CFD simulations of tunnel climate. • Life cycle cost analysis of cross-passage cooling systems using a dynamic approach. • Application on the (33 km) Koralm railway tunnel as the selected case study. When it comes into operation in 2026, the Koralmtunnel in Austria will be the world́s seventh longest railway tunnel. The installation of the power supply, telecommunications and electro-mechanical services is currently ongoing. Parts of these systems have to be protected from temperature and humidity variations and from the high dust loads which are characteristic of the tunnel atmosphere. In particular, cooling systems are required to counteract the significant amounts of heat released by some installations. Information on a large number of parameters (e.g. tunnel air temperatures) is required in the design process. However, such information is only partly available in the design stage. Hence, a prediction of tunnel air temperatures has to be made. Additionally, since hardly any information about the tunnel climate in long railway tunnels is available and in-situ measurements are not possible, as thermal conditions differ significantly between the construction/equipping phase and the operation phase, a novel methodology for the prediction of the tunnel climate had to be developed. This article presents a description of a new method comprising four main investigative steps and of its application to the Koralmtunnel as a selected case study. While steps 1 and 2 provide information about the actual cooling requirement and tunnel air temperatures for a period of 50 years, steps three and four of the investigation aim at the technical and economic optimization of cooling systems. [ABSTRACT FROM AUTHOR]

Due to environmental and economic reasons, thermal energy saving has gained more importance especially in industry. This study is concerned with the application of insulation to improve thermal energy storage in spherical shaped containers positioned high above the ground. For this purpose, the thickness of the insulation applied to spherical containers of different diameters was optimized for convection and radiation heat transfer using life cycle cost analysis. In Turkey, the mechanism of storing the thermal energy of water at different temperatures in four different climatic conditions in Turkey (Ankara, Antalya, Erzurum, and Istanbul) in a container has been investigated. The results of the study show that the optimum insulation thickness and energy savings rise as the water storage temperature and the diameter of the container increase. While there is a 46% increase in the optimum insulation thickness for the vessel diameter from 0.5m to 3m in 20 °C water, a 69% increase is achieved in 100 °C water. Similarly, 85% and 114% increases were found for the optimum insulation thickness from 20 °C to 100 °C for 0.5m and 3m, respectively. In climates with the lowest heating degree-hours (Antalya), the highest energy savings are achieved with the lowest insulation thickness. To accurately determine seasonal storage heat load, a revised heating degree-hour method using hourly solar-air temperature data is recommended. This provides a 13% increase in energy savings. • With LCC, insulation subject in above-ground spherical container is investigated. • Heating degree-hour method is used to determine annual heat load of spherical container. • Insulated container is evaluated for different storage temperatures and climatic conditions. • The use of sun-air temperature instead of ambient temperature is more sensitive to heat load. • The study can draw a clear picture about insulation of above-ground container in storage processes. [ABSTRACT FROM AUTHOR]

Wastes from concentrated animal feeding operations (CAFOs) are challenging to treat because they are high in organic matter and nutrients. Conventional swine waste treatment options in the U.S., such as uncovered anaerobic lagoons, result in poor effluent quality and greenhouse gas emissions, and implementation of advanced treatment introduces high costs. Therefore, the purpose of this paper is to evaluate the performance and life cycle costs of an alternative system for treating swine CAFO waste, which recovers valuable energy (as biogas) and nutrients (N, P, K + ) as saleable fertilizers. The system uses in-vessel anaerobic digestion (AD) for methane production and solids stabilization, followed by struvite precipitation and ion exchange (IX) onto natural zeolites (chabazite or clinoptilolite) for nutrient recovery. An alternative approach that integrated struvite recovery and IX into a single reactor, termed STRIEX, was also investigated. Pilot- and bench-scale reactor experiments were used to evaluate the performance of each stage in the treatment train. Data from these studies were integrated into a life cycle cost analysis (LCCA) to assess the cost-effectiveness of various process alternatives. Significant improvement in water quality, high methane production, and high nutrient recovery (generally over 90%) were observed with both the AD-struvite-IX process and the AD-STRIEX process. The LCCA showed that the STRIEX system can provide considerable financial savings compared to conventional systems. AD, however, incurs high capital costs compared to conventional anaerobic lagoons and may require larger scales to become financially attractive. [ABSTRACT FROM AUTHOR]

A geothermal powered absorption cooling system is considered for cooling of buildings. The system is analyzed by thermodynamic performance parameters such as cooling load and coefficient of performance (COP). An economic analysis of the system is performed to assess cost structure, potential revenues, payback periods and life cycle cost analysis. Effect of geothermal water temperature on the annual cooling cost and payback periods are investigated. A liquid geothermal source at a temperature of 100 °C with a mass flow rate of 100 kg/s is considered for İzmir city of Turkey. The COP of the ammonia-water absorption cycle is determined to be 0.441. The number of degree-days for the cooling season is calculated to be 1791 °C and cooling load is calculated to be 12,870,000 kWh by the DD (degree − days) method. The annual potential revenue of geothermal cooling is estimated to be 653,818 $/yr with simple and discounted payback periods of 5.684 and 8.816 years. The geothermal cooling is provided an annual monetary benefit of 166,610 $/yr on the entire lifetime of the system by the life cycle cost analysis. So, the unit product cooling cost is calculated to be 0.01295 $/kWh, respectively. [ABSTRACT FROM AUTHOR]

The impairment of water bodies from nutrient pollution is a challenging environmental problem that could lead to high eutrophic conditions, fish kills, and human illness, while negatively impacting industries that rely on thriving water bodies. Onsite wastewater treatment systems (OWTSs) are a major source of nutrients, however no prior studies have conducted a holistic sustainability assessment of OWTSs that considers their ability to manage nutrients at the household-level in the United States. The aim of this study is therefore to evaluate the environmental and economic impacts of conventional and advanced OWTSs with respect to their ability to remove total nitrogen (TN). Septic tank and drainfield materials were varied for conventional systems, and the advanced systems evaluated consisted of aerobic treatment units (ATUs) and passive nitrogen reduction systems (PNRSs) with nitrification and denitrification stages. Life cycle assessment and life cycle cost analysis were performed to evaluate OWTSs operating in different soil and temperature conditions. Nutrient management of the advanced OWTSs outperformed the conventional systems (96.7–100% vs. 61–65% TN removal), and resulted in less than 40% of the freshwater (0.06–0.14 vs. 0.37–0.40 kg P-eq/kg TN) and marine eutrophication (0.04–0.06 vs. 0.54–0.65 kg N-eq/kg TN). However, the tradeoff for nutrient management was higher life cycle costs ($101-$121 vs. $45-$58 USD 2015/kg TN) and environmental impacts for the remaining impact categories. Lastly, when the TN removed by the drainfield was <20%, the advanced system had lower impacts than conventional OWTSs across all impact categories except ecotoxicity. [ABSTRACT FROM AUTHOR]

Local water harvesting, demand reduction and wastewater treatment measures at a building scale can help manage water resources around the Mediterranean. This study conducts a life cycle water, energy and cost analysis of rainwater and condensate water harvesting, water conservation, wastewater treatment and three combinations of these measures over 50 years, using an apartment building in Sehaileh, Lebanon. The measures’ performance is further investigated through a comprehensive sensitivity analysis that extends the applicability of findings. Reducing water demand in the building through efficient water fixtures and appliances can decrease annual water and primary energy use by 1 534 kL and 130 GJ, respectively, while saving 530 USD every year. Wastewater treatment requires 230 MJ and costs 0.97 USD per kL of water saved, necessitating subsidies to be competitive. Rainwater and condensate water harvesting cover 4.8% and 1% of the total demand, respectively, but can reduce infrastructure spending, avoid water leakage and reduce urban run-off. Combining all measures reduces mains water supply by up to 75% for 1 MJ/kL saved and zero life cycle cost. Finally, a metered, seasonal and demand-driven water pricing scheme is recommended to better relate building occupants with the intermittent and scarce nature of water around the Mediterranean. [ABSTRACT FROM AUTHOR]

Sustainability evaluation of pavement alternatives for given traffic loading and environmental conditions has always been a challenging task for pavement designers and managers. Pavement engineers and managers mainly use life cycle cost analysis (LCCA) to make a decision while the recent focus of academic research and regulatory agencies was more on the life cycle assessment (LCA) to evaluate the environmental impacts of different pavement alternatives. LCCA and LCA for more recent technologies, such as geosynthetics, have been relatively less addressed so far. Moreover, uncertainties due to inadequate data can also reduce effectiveness of the decision making process during the planning phase. In this research, an integrated LCCA and LCA framework is developed for sustainability evaluation of different pavement alternatives based on an integrated economic and environmental trade-off analysis. The framework can effectively evaluate different pavement technologies, including flexible, concrete, geosynthetics, and their combinations under different subgrade characteristics and traffic conditions. The fuzzy composite programming (FCP) is used: (i) to deal with the uncertainties associated with limited data and vagueness in experienced judgment, (ii) to integrate the results obtained from LCCA and LCA, and (iii) for final ranking of pavement alternatives. For final selection, decision makers can trade-off between cost and environmental impacts over the life cycle of the pavement alternative. The study results indicate that geosynthetics can be used to enhance the pavement service life for low volume roads with optimized cost and minimum environmental impacts. [ABSTRACT FROM AUTHOR]

This study aims to conduct the nonlinearity analysis of the shading effect on the technical–economic performance of the building-integrated photovoltaic blind (BIPB), which is designed as a preliminary study to evaluate the feasibility of the BIPB before its implementation. First, in terms of the technical performance of the BIPB, the shading effect due to the blind’s slat in the BIPB can have a nonlinear effect on the amount of electricity generation per unit area (AEG unit ) from the BIPB. Particularly, as the width of the PV panel increases, the AEG unit from the BIPB tends to decrease. Second, in terms of the economic performance of the BIPB, the feasibility of the BIPB depends on the type of investment values. Specifically, as the width of the PV panel increases, the NPV 25 (net present value at year 25) tends to increase; however, the SIR 25 (saving-to-investment ratio at year 25) tends to decrease. That is, while the NPV 25 is determined to be highest at US$82,869 when the width of the PV panel is 50 mm, the SIR 25 is determined to be highest at 2.90 times when the width of the PV panel is 10 mm. The main findings of this study can be used to clearly define the design specifications of the BIPB before its implementation, which ensure to meet the client expectations on various objectives, such as technical performance (e.g., the AEG unit from the BIPB) and economic performance (e.g., NPV 25 and SIR 25 ). [ABSTRACT FROM AUTHOR]

Assessment of life cycle costs and environmental impacts of pavements has become an essential component of roadway design and asset management. The existing literature reveals that the economic and environmental sustainability of pavements depend on specific project characteristics. Hence, recent studies have called for real world case studies of pavement construction projects to better understand how the life cycle costs and environmental impacts of pavements vary based on different project characteristics. To this end, present study conducted comprehensive LCA and LCCA analyses to investigate the sustainability of different pavement alternatives for the SR 836-Southwest Extension Project in Miami, Florida. The study considered the agency costs and impacts as well as various use phase impacts and costs including those connected with pavement vehicle interaction and work zone traffic delays. In addition, the uncertainty related to the costs and impacts of construction and maintenance activities was assessed. The results indicated that at 90% confidence interval the flexible pavement design has lower cost and environmental impacts in the construction phase. However, when all phases are taken into consideration, the rigid pavement alternatives have lower environmental impacts and costs. The analysis also examined the sensitivity of the results to different parameters such as the discount rate and future traffic growth rate. The results of the sensitivity analysis indicated that the flexible pavement design has lower agency costs compared to rigid pavements at discount rates less than 4%. For discount rate values greater than 4.5%, the rigid pavement leads to lower life cycle costs. [ABSTRACT FROM AUTHOR]

This work computes and compares the life cycle costs of two different road tunnel pavements and their corresponding lighting systems. The study evaluated rigid and flexible pavements during life periods of 20 and 30 years for different traffic conditions and for tunnel lengths between 750 m to 2000 m. The design of the pavements and lightening systems, and their corresponding maintenance strategies, followed the requirements stated in current Italian standards. This information was used to estimate the net present values of the construction and maintenance costs for both the pavements and the tunnel lighting systems, using official unit prices valid in Italy. The results showed that for tunnels equal or shorter than 1000 m, the option of using a concrete pavement offered a better economic and technical solution from the initial year of service in comparison to the flexible structure. For tunnels equal or longer than 1200 m, the discounted costs related to concrete pavements were slightly higher than those obtained for the asphalt pavement. However, due to the low pavement maintenance and lightening system costs, the concrete pavement reaches a break-even point in these cases after a few years of service. The results also suggest that the expected traffic level in the tunnel has a neglectable impact in the economic analyses, independently of the type of pavement or tunnel length. This study demonstrates that the quantification of the life cycle costs related with the selection of the road type is an efficient practice to support decision-making processes during the design stage of a tunnel structure. [ABSTRACT FROM AUTHOR]

The increase of renewable energy sources (RES) installations all over the world during the past decades leads to a more sustainable energy scenario, however some drawbacks still persists and hinder the complete replacement of traditional fossil fuels. One of the main challenging issue is related to the intermittent production that generates serious problem in the power grids operations. Battery energy storage systems (BESS) represent one of the most promising technology which can help to overcome this issue, revolutionizing the way in which electrical power grids are designed and operate. The main aspects of these devices are related to the grid energy management, increasing the host capacity of RES, the system reliability and the users’ self-consumption. However, even energy storage systems present several pitfalls. They should be correctly maintained over the lifetime and they cannot be completely recycled at the end of their life, in addition, maintenance, decommissioning and disposal costs represent a significant share of the total cost. So as to consider these aspects in a holistic model the present work proposes a life cycle cost (LCC) model, which take into account all the most relevant cost components during the entire operation of the system. [ABSTRACT FROM AUTHOR]

It is expected that the rooftop photovoltaic (PV) systems can realize net-zero energy solar buildings (nZESBs), but it is not enough by itself. To realize 100% of nZESBs, the smart photovoltaic system blind (SPSB) was proposed to generate electricity in the PV system and to reduce indoor cooling demands through the shading effect in the blind system. Before its implementation, this study aims to investigate the impact of the proposed SPSB on nZESBs, which is conducted in three ways (i.e., technical, economic, and political analyses). The detailed results can be summarized as follows: (i) technical analysis: when applying the SPSB CIGS&2-axis (which represents the SPSB with the copper-indium-gallium-selenide (CIGS) PV panel and the two-axis tracking system), its energy self-sufficiency rate was determined to be 1.25–2.31 times superior to other alternatives; (ii) economic analysis: in terms of the NPV 25 (net present value at year 25), SPSB CIGS&2-axis was determined to be 1.41–2.97 times superior to others; in terms of the SIR 25 (savings-to-investment ratio at year 25), 1.14–1.26 times; and in terms of the break-even point, 1.4–3.0 years; and (iii) political analysis: the grid-connected utilization plan including solar renewable energy certificates (GC incl.SREC plan) was determined to improve the economic profitability of the proposed SPSB. [ABSTRACT FROM AUTHOR]

Green buildings are gaining popularity in Australia with the applications of Green Star rating scheme. However, the credit for using timber materials in the rating scheme, while timber being a significantly used material in the fast growing residential construction industry, does not adequately guide designers and builders on the selection of the best timber types for residential applications from the life cycle perspective. This research presents the analysis on the life cycle cost of timber materials in their various applications for residential buildings in Australia and thereby provides guidance on how to best meet the requirement set out in the timber credit in the Green Start rating scheme. Structured interviews were used to collect the data on the cost of timber materials in their lifetime from builders, tradesmen and other residential construction professionals. Three sets of cost information were received under each application, for the individual timber species against three conditions (low, medium and extreme weather) with reference to residential buildings. Based on life cycle cost analysis results, the most suitable timbers for different applications are recommended. [ABSTRACT FROM AUTHOR]

Ongoing climate action programs are prompting more stringent energy performance standards for buildings. Consequently, energy retrofitting of existing buildings has become a common climate action initiative around the world. Building owners are keen to assess the technical and financial feasibility of energy retrofitting in pre-project planning stages. Life cycle cost analysis (LCCA) involves assessment of the economic cost of an asset or a service. LCCA, which is a data-intensive process, is heavily affected by data uncertainties; however, traditional deterministic LCCA models are oblivious to data uncertainty and this can have a significant effect on the final decision. As a solution, this paper proposes a novel LCCA approach for building energy retrofits. The proposed approach calculates life cycle cost (LCC) by adopting fuzzy set theory. In order to illustrate the proposed methodology, a case study was conducted for a public building operated in the Okanagan region of British Columbia, Canada. Two energy retrofit alternatives − a major retrofit and a deep retrofit − were compared using the proposed fuzzy set theory-based approach and the traditional deterministic LCCA approach. Even though the deterministic result had a strong membership to the fuzzy membership function of the LCC, the range of possible LCC is wide. Use of the fuzzy-based approach would enable the forecasting of possible future LCC as a result of changes in macro-economic factors. This information would allow building managers to plan for adverse future scenarios. [ABSTRACT FROM AUTHOR]

Building energy efficiency rating (BEER) certification is an energy performance certificates (EPCs) in South Korea. It is critical to examine the cost saving potentials of the BEER-certification in advance. This study aimed to develop a prediction model for the cost saving potentials in implementing the BEER-certification, in which the cost saving potentials included the energy cost savings of the BEER-certification and the relevant CO 2 emissions reduction as well as the additional construction cost for the BEER-certification. The prediction model was developed by using data mining, life cycle cost analysis, real option valuation, and Monte Carlo simulation. The database were established with 437 multi-family housing complexes (MFHCs), including 116 BEER-certified MFHCs and 321 non-certified MFHCs. The case study was conducted to validate the developed prediction model using 321 non-certified MFHCs, which considered 20-year life cycle. As a result, compared to the additional construction cost, the average cost saving potentials of the 1st-BEER-certified MFHCs in Groups 1, 2, and 3 were predicted to be 3.77%, 2.78%, and 2.87%, respectively. The cost saving potentials can be used as a guideline for the additional construction cost of the BEER-certification in the early design phase. [ABSTRACT FROM AUTHOR]

To fully utilize low-price electricity including curtailed electricity (CE) and valley electricity (VE) in China, a hydrogen system, which can also be used for reducing peak electric power and raising the capacity factor of power supply equipment, is proposed as a solution for low-price electricity applications. The objective of the present study is to conduct a life cycle cost (LCC) analysis of hydrogen systems using low-price electricity considering three of significant application paths: 1) hydrogen is sold as a chemical material; 2) hydrogen fuels a polymer electrolyte membrane fuel cell (PEMFC) to drive an automobile; and 3) hydrogen is burned in a hydrogen combustion engine to output power. A sensitivity analysis of these hydrogen systems using either curtailed renewable electricity or VE in China is conducted. The LCC of hydrogen using CE in Path 1, Path 2, and Path 3 are $0.9700/kg-H 2 , $0.1226/kWh, and $0.1265/kWh, respectively. When using VE in Path 1, Path 2, and Path 3, the LCC are $1.5389/kg-H 2 , $0.1273/kWh, and $0.1384/kWh, respectively. The average retail price of hydrogen is $4.2/kg-H 2 in China, so the technical path utilizing hydrogen as a chemical material (Path 1) appears to be the more economically viable path. Based on the sensitivity analysis of Path 1, reducing the equipment cost, improving the hydrogen purity to increase the retail price, and enhancing the electrolytic efficiency are critical and are suggested as future research topics. The impact of the loan ratio is also analyzed in this work. [ABSTRACT FROM AUTHOR]

Hydrogen used for production of electricity through electrolysis using renewable energy systems is a costlier proposition. To date 96% of hydrogen production occurs from steam reformation of fossil fuels. Water splitting method from high temperature cracking, photo electrolysis, or biological decomposition processes, are in the research stage. Life cycle cost analysis on hydrogen economy as transport fuel with fuel cell combine, including resolving its storage and transportation problems with cost of hydrogen production from power generated using different types of Ocean Thermal Energy Conversion (OTEC) plants, are evaluated. Scope of availability of hydrogen refuelling station from 100 MW (net power) OTEC plant could be determined. Advancement in OTEC technology could help in developing 2nd/3rd generation plants (using solar hybrid OTEC; Uehara cycle). The scope of by-product availability can make its electricity production cost much cheaper and would make a viable proposition in producing OTEC powered hydrogen. This is suggested to resolve the challenges in hydrogen production economy. [ABSTRACT FROM AUTHOR]