Life Cycle Cost Analysis Research Articles

Comparative thermoeconomic assessment of renewable-driven hybrid-cooled sustainable greenhouses for subtropical regions

The rapid population growth in subtropical regions and heavy reliance on food imports have led to many countries facing food insecurity. In subtropical regions, the combination of high ambient temperatures, intense solar radiation, lack of fertile soil, and limited freshwater resources create an inadequate environment for agriculture production. Without sustainable and innovative solutions, cultivation in subtropical regions will become energy-intensive, expensive, and susceptible, if not entirely unattainable. Therefore, this research work delves into assessing the thermoeconomic performance of 10 renewable-driven hybrid-cooled greenhouse integrated systems based on different solar power generation technologies, cooling cycles, and desalination systems. Four greenhouse configurations are simulated: Closed greenhouse, shaded greenhouse, buried greenhouse, and buried and shaded greenhouse. Firstly, passive cooling techniques' potential to reduce active-cooled greenhouse cooling demand and water usage was investigated, taking into account the need to provide crops with adequate environmental temperature, solar irradiation, and ventilation. Secondly, a detailed thermodynamic analysis was conducted to obtain the overall energy and exergy efficiencies of the investigated greenhouse integrated systems. Thirdly, a comparison of solar panels area requirement for the greenhouse integrated systems was performed. Finally, a comprehensive life cycle cost analysis of the examined integrated systems for the hybrid-cooled greenhouses was done to compare their economic performance. The results showed that the adopted passive cooling methods reduced yearly cooling load by 34.2–58.1%, evapotranspiration during maximum cooling load day by 17.4–34.1%, solar panels area by 8.5–32.1%, and integrated systems' life cycle cost by 5.6–28.6%. Greenhouse integrated systems powered by photovoltaic panels obtained the lowest life cycle cost, while greenhouse integrated system-4 driven by concentrating photovoltaic thermal panels was found superior in terms of panels area.

Life cycle assessment and life cycle cost analysis of different walling materials with an environmental approach (comparison between earth-based vs. conventional construction techniques in Iran)

PurposeClimate change, environmental concerns, and economic problems pose challenges to the construction sector in Iran, which must provide affordable solutions while addressing environmental issues. Hence, natural earthen building materials are critically needed to reduce energy-intensive and costly construction practices dramatically. The purpose of this paper is to provide a framework for comparing life cycle assessments (LCA) and life cycle costs (LCC), for load-bearing walls of an single-family affordable housing unit in a desert part of Iran, Ardakan City.MethodsTo do so, both LCA and LCC for the unit were performed, considering a cradle-to-site perspective. For this purpose, 22 load bearing wall systems are assessed, including 18 stabilized and unstabilized earthen construction techniques, such as adobe, rammed earth (RE), and compressed earth block (CEB), in addition to four conventional wall assemblies of fired brick (FB), autoclaved aerated concrete block (AAC), ceramic block (CB), and concrete masonry unit (CMU). As well as assessing the environmental impact and life cycle costs associated with the life cycle of each wall, the optimal assembly of the wall is also examined.ResultsResults show that unstabilized earthen walling alternatives have significantly lower environmental impacts than conventional materials.ConclusionsSensitivity analysis indicates that by utilizing local materials to the maximum extent possible, impacts can be further minimized. Considering the results, transportation may even account for a greater proportion of EI than wall components.

Thermal insulation and energy performance's assessment of a mycelium-based composite wall for sustainable buildings

Bio-composite insulation materials play a crucial role in reducing the environmental impact of buildings. This paper numerically investigates the eco-friendly application of mycelium in south-facing walls in Marrakech, Morocco, using 2D CFD simulations. In this context, the thermal efficiency of bio-sourced insulating materials was assessed and compared to that of conventional insulating materials. The study basically aims at the time lag and the decrement factor analysis to evaluate the dynamic thermal performance of a multilayer wall insulated with mycelium. A life cycle cost analysis (LCCA) is performed to establish the optimal thickness of the mycelium insulation, which was turned out to be 0.08 m. This optimization leads to a substantial improvement in energy efficiency, resulting in energy savings increasing by 87.4 % in winter and 55.9 % in summer. Besides, during the last 72 h of the simulation, the indoor surface temperature drops by approximately 4 °C on summer days and raises by approximately 1 °C on winter days. The thickness of mycelium insulation was found to have a significant impact on energy savings, increasing them from 56 % to 93 %, and representing nearly a 1.7-fold improvement. The study has also targeted annual CO2 emissions to reveal a potential reduction of around 72 % using optimal mycelium composite insulation. Finally, a comparative analysis with the guidelines of Moroccan thermal regulations was achieved. The obtained findings exhibit that the examined configuration excels in terms of thermal performance, economic feasibility, and environmental benefits.

Probabilistic approach to the sustainability assessment of reinforced concrete structures in conditions of climate change

The paper presents a probabilistic method based on two methodologies – Life Cycle Cost Analysis (LCCA) and Life Cycle Assessment (LCA), for evaluating the sustainability of reinforced concrete (RC) structures in terms of their costs and CO2 emissions. The method considers the whole life of a RC structure by taking into account CO2 initially embodied in its construction materials, the absorption of CO2 by concrete due to carbonation during the service life of the structure, potential damage to the structure due to carbonation-induced corrosion of reinforcing steel that may require repairs, and relevant costs. Since there are numerous uncertainties associated with the calculation of CO2 emissions and costs, a probabilistic approach is beneficial. The emphasis is made on RC structures made of the so-called “green concretes”, in which Portland cement is partially replaced with supplementary cementitious materials such as fly ash and ground granulated blast-furnace slag. The issue of a changing climate is also addressed. The method is illustrated by assessing the sustainability of a multi-story RC carpark made of different concrete types at three different locations (London, Paris and Marseille) for present and future climate conditions. This assessment's results show that using green concretes leads to a major reduction in CO2 emissions and a small decrease in the life-cycle cost of the carpark RC elements. The relative sustainability performance of green concretes slightly improves compared to Portland cement concrete for future climate conditions.

Enhancing economic-social sustainability through a closed-loop citrus supply chain: A life cycle cost analysis

The focus on food supply chain (FSC) sustainability has grown due to demand, food loss and waste, and environmental impacts. This study aims to quantify citrus life cycle costs (LCC) and determine the main drivers and their contributions. LCC was used to assess the cradle-to-grave cost of 1 kg of citrus sold to consumers at the retailer stage. A comparison was made between an existing citrus supply chain (SC) and a proposed closed-loop structure. In addition to the current citrus SC, four different cases were analyzed and evaluated: the centralized linear citrus SC, the centralized linear citrus SC with a 33 % increase in labor income, the centralized closed-loop citrus SC, and the centralized closed-loop citrus SC with a 33 % increase in labor income. The results showed significant reductions in functional unit's (FU) costs of 48 %, 38 %, 54 %, and 44 %, respectively, compared to the current citrus SC. Labor accounted for 47–62 % of the FU costs, while agriculture inputs and transportation contributed 15–28 % and 12–16 %, respectively. The study revealed that a centralized citrus closed-loop SC improves economic viability, especially when recycling citrus waste as compost for farms. Transportation currently contributes the most to FU costs (45 %), but in the closed-loop citrus SC, labor becomes the highest contributor (62 %). This cradle-to-grave citrus SC approach identifies drivers and contributions to the FU's costs, showcasing differences when integrating a circular economy. Future research may explore the impact of other byproducts on FU costs.

Comparative life cycle cost analysis of bio-valorized magnetite nanocatalyst for biodiesel production: Modeling, optimization, kinetics and thermodynamic study

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@Fe3O4, 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.

Sustainable next-generation single-component geopolymer binders: a review of mechano-chemical behaviour and life-cycle cost analysis

Sustainable next-generation single-component geopolymer binders: a review of mechano-chemical behaviour and life-cycle cost analysis

Development of thermal insulation panels bio-composite containing cardboard and date palm fibers

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.

Multidimensional Time-Series Life Cycle Costs Analysis of Intelligent Substation

Comprehensive and accurate LCC (Life Cycle Costs) of intelligent substations are conducive to improving operation efficiency and reliability of power transmission. To reduce maintenance costs and enhance assets utilization, multiple dimensional time series LCC analysis of intelligent substation based on PCA-LSTM (Principal Component Analysis Long-Term Short-Term Memory) is proposed in this paper. This paper first discusses the differences between smart substations and conventional substations in LCC analysis. Because it has an advantage over RNN in handling gradient vanishing and explosion, LSTM (Long-Term Short-Term) is used instead of RNN (Recurrent Neural Network). Considering that LCC is a comprehensive study which contains large number of variables, PCA (Principal component analysis) is utilized to deal with the data dimensionality reduction preprocessing. Results show that PCA-LSTM performs better in RMSE (Root-Mean-Square Error), MAE (Mean Absolute Error), MAPE (Mean Absolute Percentage Error), as 0.182, 0.154 and 15.84%, respectively. In our case, the computation time is about half that of the pure LSTM. And the calculation efficiency is 2.2 times compared to the original.

Life cycle cost analysis of a floating wind farm in the Norwegian Sea

The offshore wind energy industry has witnessed rapid growth in the past decade. Still, there is a lack of commercial floating wind projects due to the relatively high development costs and other factors. To facilitate the holistic evaluation of floating wind farms in Norway, this article investigates the levelized cost of energy of a floating offshore wind farm and its economic feasibility. The Troll field west of Bergen, Norway, is assumed to be the target offshore site, and a farm size of 50 wind turbines with a lifespan of 25 years are considered. Each floating wind turbine has a 15-megawatt turbine mounted on a semi-submersible floater. Based on detailed analysis, the levelized cost of energy of the wind farm is estimated to be approximately 100.7 $/MWh. The capital expenditure is the most prominent cost and constitutes 63.1% of the total cost, and the operational expenditure constitutes the remaining 36.9%. Further, sensitivity analyses show the influence of the lifespan, capacity factor, and project discount rate on the levelized cost of energy. The present study contributes to techno-economic evaluation of floating wind projects at an early phase.

Determination of optimum insulation thickness in submarines

One of the most effective ways to save energy for cooling and heating applications is thermal insulation. Because of this, determining the ideal insulation thickness is a popular topic for publications. The purpose of this study is to determine the appropriate insulation thickness needed for a submarine’s external construction while it is cruising in various locations. Since seawater makes up a submarine’s external environment, situations involving five distinct sea-water temperatures from around the globe have been studied. There are five of them: the Med-iterranean, Marmara, Aegean, Black Sea, and Sakhalin, which is in the North Pacific Ocean and has the coldest seawater on earth. By using the idea of degree-days, the annual cooling and heating needs of submarines in various regions have been computed. Based on life cycle cost analysis, optimization has been accomplished. In the beginning, the results of a study published in the literature supported the calculation methods utilized. The use of insulation materials such as rock wool, glass wool, polyurethane, expanded polystyrene, fiberglass, and foam glass, as well as fuel oil to run the generator, has been taken into account in a number of calculations, including the best insulation thickness, annual savings value, annual energy cost, and payback period. The findings indicate that depending on seawater temperatures and in-sulation materials, the ideal insulation thicknesses range between 2 and 12 cm, energy savings between 8.5% and 90%, and payback periods between 1.1 and 10 years.

A Life Cycle Cost Analysis—Relevant Method Supporting the Decision to Establish an Apple Orchard in an Organic System

The life-cycle cost analysis is a method used to assess long-term economic efficiency among equivalent competing processes or products. The purpose of this paper is to investigate the nature and level of costs for an organic orchard located in Southern Romania, using a complex approach covering the entire chain of production, through its life span. The research results, based on a dynamic analysis and an integrated evaluation of the orchard’s performance, were ranked on investment and operational costs and broken down into three categories (establishment, production, post-harvest, transport costs). The highest costs, representing 151,726 EUR/ha/20 years, about 52.72% of the total operational costs and 50.4% of the total farm costs/ha/20 years, were recorded in the exploitation stage. The scenarios for the sensitivity analysis considered different levels of average yields (40 and 60 tons/ha, respectively) with different rates of sold productions (85%, optimistic scenario; 70%, pessimistic scenario). The hot points identified at the production stage were the use of agricultural machinery, several pesticides, the costs of seedlings, anti-hail nets, plastic boxes, and labor costs, while at the post-harvest stage, there were those related to labor and energy consumption. The transport stage had important costs with respect to tractor operations and the track.

Optimal design and operation of the hybrid absorption-compression chiller plants - Energy and economic analysis

A hybrid network integrating absorption and compression chillers is a suitable solution to respond to the variable cooling demand in a large-scale chiller plant, in regions with multiple energy sources. However, the design and control challenges of such networks remain uncharted, lacking a comprehensive approach. This study presents a general procedure for designing a hybrid chiller network for a building with an arbitrary annual cooling demand distribution. The procedure determines the optimal configuration considering the different capacity ratios of absorption to compression chillers, chiller numbers, and arrangements. Utilizing the Particle Swarm Optimization algorithm, the optimal chiller loading distribution is found for each configuration. Life cycle cost analysis aids in selecting the optimal configuration. Simulations conducted in TRNSYS, reveal that optimal energy and economic choices depend on the natural gas and electricity price ratio. The best energy performance occurs at a low capacity ratio, while the economic trend varies with capacity ratio for different price ratios. The potential reduction in life cycle cost associated with the configuration, when compared to the full absorption baseline and the full compression baseline, can reach up to 7,210,000 $ (72.6%) and 724,000 $ (24.5%), respectively. From an environmental perspective, compared to the full absorption baseline and the full compression baseline, hybrid chiller configurations reduce the CO2 emissions for up to 899 tons (68.8%) and 52 tons (11.3%), respectively.

Seismic performance of RC bent columns: Experimental, numerical and life-cycle cost analysis

Reinforced concrete (RC) bent structures are widely used in single-story industrial buildings, with a considerable portion of them located in high-intensity seismic areas. Therefore, it is significant to study the seismic performance of the RC bent column while keeping construction costs in mind. To evaluate the seismic performance of the RC bent column from an economic perspective, pseudo-static tests combined with construction cost analysis were first carried out on three RC bent columns designed according to different versions of Chinese codes. A numerical simulation method based on the extended finite element method (XFEM) for the RC bent column was then established and verified. Subsequently, the relationship between the local damage index related to the apparent damage characteristics and the overall damage index was established by conducting numerical analysis on RC bent columns with different design parameters. Based on the established relationship between the local and overall damage indexes, a calculation method for the residual bearing capacity based on apparent damage was developed. The results show that, when compared to the constructional requirements in the Chinese code for seismic design of industrial and civil buildings published in 1978 (TJ11–78), the constructional requirements in the Chinese code for seismic design of buildings published in 1989 (GBJ11–89) can effectively reduce the stress concentration at the column bottom and delay the formation of the plastic hinge with minimal cost increase, while the constructional requirements in the Chinese code for seismic design of buildings published in 2016 (GB50011–2010) can further effectively reduce the damage to the upper column. Besides, the constructional requirements in GBJ11–89 and GB50011–2010 can improve the energy dissipation and maximum bearing capacity of the RC bent column while decrease the cost/ductility coefficient by more than 5.0 %. The proposed calculation method can effectively predict the residual bearing capacity of earthquake-damaged RC bent columns by comparing the calculation results to the test results.

Assessing life cycle cost and environmental impact for office building construction in Saudi Arabia

ABSTRACT The continuous growth of the construction sector in Saudi Arabia will result in social, environmental, and economic implications. To this end, this study focuses on selecting optimal structural and external envelope systems for an office building in Al Khobar, Saudi Arabia. Our research’s novelty lies in the fusion of life cycle cost (LCC) and life cycle impact (LCI) assessment models to optimize structural and envelope choices, a methodology that has real-world applications for the sustainable construction of office buildings. The study findings offer a substantial contribution to the evolving field of sustainable construction practices by enhancing cost-efficiency and environmental performance. The proposed models evaluate different external envelope materials, including concrete masonry unit (CMU), insulated CMU, limestone cladding, autoclaved aerated concrete (AAC), three types of glazing (double, triple, and Nanogel), and two structural systems (steel frame and reinforced concrete frame), considered over a 30-year lifespan. Our methodology integrates advanced tools, including Autodesk Revit for precise building modeling, Design Builder software for energy consumption simulations, and One Click LCA software for life cycle assessments. The LCC analysis reveals the most cost-effective option as reinforced concrete with insulated CMU and triple glazing, saving 5.6% or 11,962,496 Saudi Riyals compared to the baseline. Moreover, insulated CMU with Nanogel glazing demonstrates a remarkable 22% annual energy savings, equivalent to 397,469 Saudi Riyals. The proposed framework provides facility managers with comprehensive guidelines for updating conventional office buildings into sustainable ones.

Feasibility of textile envelope integrated flexible photovoltaic in Europe: Carbon footprint assessment and life cycle cost analysis

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.

Application of Green Retrofitting Ready Mix Concrete Plant in Indonesia to Increase Financial Benefits and Reduce Environmental Issues: A Case Study

Currently, the Indonesian government continues to encourage the realization of sustainable development. The green concept is a sustainable development trend in the construction material industry. The concrete industry plays a vital role as a supplier of concrete materials in construction, so its availability is essential. The role of concrete industry itself has a negative impact on the environment. Stakeholders increase the cost of green retrofitting so that the industry or building becomes eco-friendly. The research method was carried out using a process case study, namely, how to implement green retrofitting cost performance in the concrete industry using Value Engineering and Life Cycle Cost Analysis. Theoretically, the research results provide additional knowledge for academics; practitioners can provide problem-solving to get an overview of the implementation of the green concept in the industry regarding the flow of implementation and the benefits of savings in an environmentally friendly production process. The application of value engineering in the green retrofitting of the concrete industry has increased the cost performance of green retrofitting by 8.66% with a return of 3 years and 8 months and increased the functions and benefits of an eco-friendly and sustainable concrete industry

Process Optimization of Biodiesel Production Using Waste Snail Shell as a Highly Active Nanocatalyst

In this work, we reported the transesterification of soybean oil (SO) to biodiesel using a basic CaO nanocatalyst produced by sequential calcination, hydration, and dehydration of waste snail shells. Response-surface methodology (RSM) and a central composite design (CCD) were used to predict several optimization parameters. 1H-NMR confirmed that 98.5% of the SO was transformed into methyl ester biodiesel. Under the optimal reaction parameters of catalyst loading of 6 wt. %, methanol to oil molar ratio of 8 : 1, reaction duration of 3 h, and temperature of 70°C, an excellent biodiesel yield of 96.1% was obtained. The transesterification of SO to biodiesel displayed a significantly low activation energy (30.45 kJ mol-1), whereas, the turnover frequency of the transesterification reaction was found to be 0.0063 mol g-1 h-1. The catalyst showed excellent stability and was consecutively used for six cycles without a significant decline in catalytic activity. Based on life cycle cost analysis (LCCA), the estimated cost for producing 1 kg of biodiesel in this study comes out to be just $0.935, signifying its strong potential for widespread commercial use.

Life cycle cost analysis of LED retrofit and luminaire replacements for four-foot T8 troffers

Lighting makes up 17% of electrical loads and the largest energy end use in commercial buildings. Linear fixtures are among the largest opportunities for energy efficiency improvement, given their long operating hours. With continued, rapid light-emitting diode (LED) development and more LED replacement products on the market, lighting replacement decisions become more complex and warrant re-examination. With a goal to inform building managers and other decision-makers with practical guidance on lighting replacement, this study is a life cycle cost (LCC) analysis that compares the cost–benefit of six replacement options (one fluorescent and five LED) for a 0.61 m by 1.22 m (2 ft by 4 ft) T8 recessed troffer based on data for 168 lighting products from an online vendor. Results show that direct wire (i.e. unballasted) LED retrofits are the least-cost option to replacing fluorescent lamps in terms of normalized LCC. Plug-and-play lamps suffer from a lock-in with ballasts, but their ease of installation can help spur LED adoption. In cases where an existing ballast is still usable, hybrid LED retrofits provide the least upfront cost option by deferring the cost of rewiring. LED luminaires can offer improved aesthetics and reliability; however, they have high upfront cost. Among them, luminaires with replaceable lamps offer lower cost than those without.

Extreme state prediction of long-span bridges using extended ACER method

An accurate prediction of the future service state of long-span bridges is crucial for the structural reliability evaluation, maintenance planning, and further life-cycle cost analysis. By extending the average conditional exceedance rate (ACER) statistical model and applying input–output data collected through a structural health monitoring (SHM) system, this paper proposes a novel methodology for predicting the future service state of long-span bridges. The advantages lie in the consideration of the main excitation load as the structural input and the strain response of the bridge as the output. Therefore, a mapping relationship between the extreme excitation load and extreme strain could be established, and the future service state of long-span bridges could be predicted. The proposed method comprises three steps: (1) extraction of the ambient temperature-induced strain and vehicle-induced strain from the measured strain series through the SHM system using the baseline estimation and denoising with sparsity (BEADS) method, (2) establishing statistical models of the extreme values of different excitations (input) and structural strains (output) using a cascade of conditioning approximations and the ACER to obtain the tail trend of the data and extrapolating it, and (3) establishing a functional relationship between the input and output extreme values based on the same conditions of the regression period at the target prediction level, after which the future service state of long-span bridges can be predicted. The proposed method is applied to a case study of the Jinchao Bridge in Guangdong Province, China, and the results are expected to provide a scientific reference for the design of new bridges and in the maintenance of existing ones in service.