Life Cycle Cost Model Research Articles

A Design Method for Product-Service Systems based on Life Cycle Cost Model

A Design Method for Product-Service Systems based on Life Cycle Cost Model

基于全寿命周期成本模型的输变电设备检修策略研究

当前电力设备检修策略制定过程中未考虑全寿命周期成本(Life Cycle Cost, LCC)因素，存在着检修策略无法实现经济效益最大化的问题。本文以定期检修和状态维修为例，基于全寿命周期成本模型修正了常用的输变电设备检修策略。在保证系统安全稳定运行的前提下，制定出合理的检修策略，同时实现经济性的目标，具有工程实用性。 The factor of LCC (Life Cycle Cost) is not considered in the present process of making maintenance strategy for power equipment, which leads to the failure of the maintenance strategy to maximize the economic benefits. In this paper, these common maintenance strategies for transmission and transformation equipment are corrected based on the LCC model considering time based mainte-nances and condition based maintenance. On the premise of ensuring the safe and stable operation of the system, some reasonable maintenance strategies of highly valuable in engineering are formulated, and the economic goal is realized.

Integrating Life Cycle Costing (LCC) and Life Cycle Assessment (LCA) Model for Selection of Centralized Chilled Water Generation — Review Paper

This paper presents a review of literature relating to Life Cycle Costing (LCC) and Life Cycle Assessments (LCA) in Gas District Cooling plant. The gas district cooling plant uses either vapour compression process or absorption process for the chilled water generation. Both processes have impacts on the economic aspects as well as the contribution to CO 2 emissions; thus, integration of the cost and environmental analysis of both processes are necessary. An extensive body of literature exists on both subjects, however, there is very limited number of available literature on the integration of LCC and LCA. The purpose of this review is to find the most suitable optimization model which can integrate the LCC and LCA to provide the best decision in choosing the most cost-effective and environment-friendly system. This review assesses the literature from thirty-four journals, research papers, and case reports from the year 1995 to 2017. The result of this review shows that the goal programming methodology is the appropriate method for integrating LCC and LCA because it provides the optimal decision in choosing the most cost-effective, environment-friendly system for the chilled water generation.

Quantitative Assessment of the Impact of Alternative Manufacturing Methods on Aeroengine Component Lifing Decisions

Static structural aeroengine components are typically designed for full lifetime operation. Under this assumption, efforts to reduce weight in order to improve the performance result in structural designs that necessitate proven yet expensive manufacturing solutions to ensure high reliability. However, rapid developments in fabrication technologies such as additive manufacturing may offer viable alternatives for manufacturing and/or repair, in which case different component lifing decisions may be preferable. The research presented in this paper proposes a value-maximizing design framework that models and optimizes component lifing decisions in an aeroengine product–service system context by considering manufacturing and maintenance alternatives. To that end, a lifecycle cost model is developed as a proxy of value creation. Component lifing decisions are made to minimize net present value of lifecycle costs. The impact of manufacturing (represented by associated intial defects) and maintenance strategies (repair and/or replace) on lifing design decisions is quantified by means of failure models whose output is an input to the lifecycle cost model. It is shown that, under different conditions, it may not be prudent to design for full life but rather accept shorter life and then repair or replace the component. This is especially evident if volumetric effects on low cycle fatigue life are taken into account. It is possible that failure rates based on legacy engines do not translate necessarily to weight-optimized components. Such an analysis can play a significant supporting role in engine component design in a product–service system context.

Life-Cycle Cost Model and Design Optimization of Base-Isolated Building Structures

Design of economic structures adequately resistant to withstand during their service life, without catastrophic failures, all possible loading conditions and to absorb the induced seismic energy in a controlled fashion, has been the subject of intensive research so far. Modern buildings usually contain extremely sensitive and costly equipment that are vital in business, commerce, education and/or health care. The building contents frequently are more valuable than the buildings them-selves. Furthermore, hospitals, communication and emergency centres, police and fire stations must be operational when needed most: immediately after an earthquake. Conventional con-struction can cause very high floor accelerations in stiff buildings and large interstorey drifts in flexible structures. These two factors cause difficulties in insuring the safety of both building and its contents. For this reason base-isolated structures are considered as an efficient alternative design practice to the conventional fixed-base one. In this study a systematic assessment of op-timized fixed and base-isolated reinforced concrete buildings is presented in terms of their initial and total cost taking into account the life-cycle cost of the structures.

Life Cycle Cost Analysis of Three Types of Power Lines in 10 kV Distribution Network

There are three types of power lines in the 10 kV distribution network in China, i.e., copper power cables, overhead power conductors and aluminum alloy power cables. It is necessary to give a comprehensive evaluation to choose the type of power line in some delicate practical engineering. This paper presents a life cycle cost (LCC)-based analysis method for the three types of power lines. An LCC model of the power line in the 10 kV distribution network is established, which considers four parts: investment cost, operation and maintenance cost, failure cost and discard cost. A detailed calculation model for the four parts is presented, and to calculate the failure cost, the Monte Carlo algorithm is employed to simulate the values of expected energy not supplied (EENS). Two practical 10 kV power line projects in Fujian Province in China were analyzed based on the proposed LLC model and corresponding developed software, which has helped the power company select the appropriate power line successfully.

Simplified seismic life cycle cost estimation of a steel jacket offshore platform structure

The purpose of the present paper is to develop a simple methodology for seismic life cycle cost (LCC) estimation for a steel jacket offshore platform structure. This methodology accounts for accuracy of LCC modelling as well as simplicity of application. Accuracy is maintained through incorporating the effect of aleatory and epistemic uncertainties in the LCC estimation framework. Simplicity is achieved by using equivalent single-degree-of-freedom (ESDOF) system instead of the full structure and by eliminating full incremental dynamic analysis and fragility analysis. Instead, an approximate fragility curve and a localised incremental dynamic analysis curve are used along with a probabilistic simple closed-form solution for loss estimation. In the design of model structures, different bracing systems are used for the seismic design of the offshore platform, such as conventional and buckling-restrained braces. The proposed LCC methodology is validated through comparison with the results from a more rigorous method. It is found that even though the proposed methodology results in a slightly different solution compared to the reference method, the method can be used as an efficient tool for preliminary LCC evaluation of structures.

Developing a life cycle cost model for real-time condition monitoring in railways under uncertainty

The Shanghai Transport Committee has estimated that passenger traffic increased fivefold between 2005 and 2014, and will continue to increase. At the same time, the maintenance costs of the Shanghai Metro have increased to about six times their original value. To ensure reliability, availability, maintainability and safety (RAMS) in railways, equipment sometimes needs to be upgraded; new technology is an effective way of modernizing the system. Condition monitoring techniques are considered to be a pragmatic approach to improve RAMS in railways. Bearings are seen to be a key factor in the successful operation of railways, as their performance is related to safety and reliability. To meet the safety requirements, an efficient method is to implement a real-time condition monitoring (RTCM) technique. To evaluate the economic cost of this investment in RTCM, the life cycle cost (LCC) should be considered. A Petri net combined with the Monte Carlo method is used to simulate the LCC evaluation process and a case study of how to employ this method is presented.

Comparison study on life-cycle costs of different trams powered by fuel cell systems and others

Proton exchange membrane fuel cells have shown great promise for powering trams. Hydrogen refueling stations and a fuel-cell system incur initial vehicle costs that are higher than a pantograph/catenary tram or contact-rail tram. In this paper, a life-cycle cost analysis is conducted for five trams: a pantograph/catenary tram, a contact-rail tram, and three fuel-cell hybrid trams. Characteristics of fuel-cell hybrid trams are compared with contemporary transit systems. A simplified life-cycle cost model, including costs for the initial infrastructure and powertrains, daily operation and power plant replacement, is proposed and calculated with parameters. A sensitivity analysis is also performed. Results show that the life-cycle costs of trams are almost proportional to the rail-line length. The initial costs of a fuel-cell hybrid tram are less than a pantograph/catenary tram or contact-rail tram. The life-cycle costs of fuel-cell hybrid trams are highly dependent on combination factors of hydrogen price, fuel-cell price and battery price. Charging facilities for fuel-cell hybrid trams are favorable when hydrogen price is in a high level. Greenhouse gas emissions of trams are almost equivalent.

Comparative Life Cycle Cost Analysis of Hardening Options for Critical Loads

In order to determine the most cost effective alternative among hardening options of power systems, the direct monetary benefits should be evaluated above all other things. Therefore, this paper presents a life-cycle cost model which describes total monetary costs experienced in annual time increments during the project with consideration for the time value of money. In addition, to minimize the risks associated with estimated cost errors due to uncertainties of input data, the stochastic input data are considered. Using the Monte Carlo method, the probabilities and cost ranges in the case studies can be predicted, in turn resulting in better decisions in the selection of hardening options which are cost effective.

Economic viability analysis for icing blades detection in wind turbines

Reliability, availability, maintainability and safety (RAMS) of wind turbines in cold climates are closely related to ice accretion. The deterioration of RAMS of the wind turbines involves costs such as Operation and Maintenance costs and energy losses. Systems to monitor the condition of the wind turbines play a key role in the wind energy industry to decrease the costs mentioned above and to improve the maintenance management. This research presents an economic study of the life cycle cost (LCC) for ice condition monitoring systems in wind turbines. In particular, the paper studies the economic feasibility of different commercial ice detection systems through a LCC model when wind turbines are exposed to different scenarios. To date, the scientific literature does not collect any study about the LCC for ice detection systems using different annual rates of return, and providing a map with numerical solution. The study is extended by including a bank loan for a real point of view. The findings of this study reveal the ice detection systems that are more profitable and the selection criteria to decide the use of a bank loan. Finally, it is shown that predictive costs are much smaller than corrective cost reaching a reduction of these corrective costs with the ice detection systems.

Life Cycle Cost Modelling of Buildings with Consideration of the Risk

Abstract The paper presents an approach to evaluating a building throughout its whole life cycle in relation to its sustainable development. It describes basic tools and techniques of evaluating and analysing the costs in the whole life cycle of the building, such as Life Cycle Assessment, Life Cycle Management, Life Cycle Cost and Social Life Cycle Assessment. The aim of the paper is to propose a model of cost evaluation throughout the building life cycle. The model is based on the fuzzy sets theory which allows the calculations to include the risks associated with the sustainable development, with the management of the investment and with social costs. Costs incurred in the subsequent phases of the building life cycle are analysed and modelled separately by means of a membership function. However, the effect of the analysis is a global cost evaluation for the whole life cycle of the building.

Life cycle costing of diesel, natural gas, hybrid and hydrogen fuel cell bus systems: An Australian case study

The transit authority in Perth, Western Australia, has put several alternative fuel buses, including diesel-electric hybrid and hydrogen fuel cell buses, into revenue service over the years alongside conventional diesel and natural gas buses. Primary data from this fleet is used to construct a Life Cycle Cost (LCC) model, providing an empirical LCC result. The model is then used to forecast possible scenarios using cost estimates for next generation technologies. The methodology follows the Australian/New Zealand Standard for Life Cycle Costing, AS/NZS 4536:1999. The model outputs a dollar value in real terms that represents the LCC of each bus transportation technology. The study finds that Diesel buses deliver the lowest Total Cost of Ownership (TCO). The diesel-electric hybrid bus was found to have a TCO that is about 10% higher than conventional diesel. The premium to implement and operate a hydrogen bus, even if industry targets are attained, is still substantially greater than the TCO of a conventional diesel bus, unless a very large increase in the diesel fuel price occurs. However, the hybrid and hydrogen technologies are still very young in comparison to diesel and economies of scale are yet to be realised.

Environmental and financial performance of mechanical recycling of carbon fibre reinforced polymers and comparison with conventional disposal routes

Recovering value from carbon fibre reinforced polymers waste can help to address the high cost and environmental burden of producing carbon fibres, but there is limited understanding of the cost and environmental implications of potential recycling technologies. The objective of this study is to assess the environmental and financial viability of mechanical recycling of carbon fibre composite waste. Life cycle costing and environmental assessment models are developed to quantify the financial and environmental impacts of alternative composite waste treatment routes, comparing landfilling, incineration with energy recovery, and mechanical recycling in a UK context. Current Landfill Tax results in incineration becoming the lowest cost composite waste treatment option; however, incineration is associated with high greenhouse gas emissions as carbon released from composite waste during combustion exceeds CO2 emissions savings from displacing UK electricity and/or heat generation, resulting in a net greenhouse gas emissions source. Mechanical recycling and fibre reuse to displace virgin glass fibre can provide the greatest greenhouse gas emissions reductions of the treatment routes considered (−378 kg CO2 eq./t composite waste), provided residual recyclates are landfilled rather than incinerated. However, this pathway is found to be unfeasible due to its high cost, which exceeds £2500/t composite waste ($3750/t composite waste). The financial performance of mechanical recycling is impaired by the high costs of dismantling and recycling processes; low carbon fibre recovery rate; and low value of likely markets. To be viable, carbon fibre recycling processes must achieve near-100% fibre recover rates and minimise the degradation of fibre mechanical properties to enable higher value applications (e.g., virgin carbon fibre displacement). On-going development of carbon fibre recovery technologies and composite manufacturing techniques using recycled carbon fibres leading to improved material properties is therefore critical to ensuring financial viability and environmental benefit of carbon fibre reinforced polymer recycling.

SENSITIVITY ANALYSIS ON FLEXIBLE ROAD PAVEMENT LIFE CYCLE COST MODEL

Sensitivity analysis is a tool used in the assessment of a model’s performance. This study examined the application of sensitivity analysis on a developed flexible pavement life cycle cost model using varying discount rate. The study area is Effurun, Uvwie Local Government Area of Delta State of Nigeria. In order to determine one of the vital geotechnical engineering properties (i.e. California Bearing Ratio) of the soil samples required for this study, soil samples were taken from the subgrade of the study area using the disturbed sampling method. The laboratory test was carried out at geotechnical laboratory in Warri and in accordance with AASTHO 1993 to determine the subgrade strength. Existing data such as maintenance records, vehicular traffic counts, material costs, discount rate and pavement design data were sourced from the Delta State Ministry of Works, Effurun. These acquired data and CBR results of 5% and 6% were used for the design of three competing flexible pavement systems and Bill of Engineering Measurements obtained. These were used for the evaluation of the Life-Cycle Costs (LCCs) using present worth cost (PWC) method; varying discount rates in MS Excel spread sheets for a design life of 20 years. Regression modeling of the three scenarios was done with sensitivity analysis carried out on the developed model. The project age was used as its independent variable, while discount rate is a secondary independent variable varied by ±4%, ±8% and ±12% of the initial discount rate of 5.4% applied with the accuracy of 95%. The coefficient of determination (R 2 ) for the Hot Rolled Asphalt (HRA), Interlocking Concrete Pavement Block (ICPB) and Do-nothing models are 0.97, 0.95 and 0.99 respectively indicating a robustness of the developed models. The graphs produced from the sensitivity analysis indicate a decrease in life cycle cost with increasing interest rate for the alternatives. These results are vital for the economic evaluation of flexible pavement and transportation systems. http://dx.doi.org/10.4314/njt.v35i2.7

Integrated Life Cycle Assessment and Life Cycle Cost Model for Comparing Plug‐in versus Wireless Charging for an Electric Bus System

SummaryAn integrated life cycle assessment and life cycle cost (LCC) model was developed to compare the life cycle performance of plug‐in charging versus wireless charging for an electric bus system. The model was based on a bus system simulation using existing transit bus routes in the Ann Arbor–Ypsilanti metro area in Michigan. The objective is to evaluate the LCCs for an all‐electric bus system utilizing either plug‐in or wireless charging and also compare these costs to both conventional pure diesel and hybrid bus systems. Despite a higher initial infrastructure investment for off‐board wireless chargers deployed across the service region, the wireless charging bus system has the lowest LCC of US$0.99 per bus‐kilometer among the four systems and has the potential to reduce use‐phase carbon emissions attributable to the lightweighting benefits of on‐board battery downsizing compared to plug‐in charging. Further uncertainty analysis and sensitivity analysis indicate that the unit price of battery pack and day or night electricity price are key parameters in differentiating the LCCs between plug‐in and wireless charging. Additionally, scenario analyses on battery recycling, carbon emission pricing, and discount rates were conducted to further analyze and compare their respective life cycle performance.

철도 궤도의 수명주기비용 분석 : 고속철도 자갈궤도와 콘크리트궤도 사례 연구

In the decision-making, such as selection of structure, construction method, or time and scheme of maintenance, the evaluation of life-cycle cost(LCC) is of great importance. The maintenance cost occupy a large portion of the LCC of the railway track as well as the initial construction cost. Futhermore, the proportion of the maintenance cost is much higher in the ballasted track. Thus, the importance of the LCC evaluation is higher than in any other engineering structures. In this study, a LCC model that can consider various design parameters such as the type of track structure, annual traffic volume, axle load, train speed, and proportion of curve sections and engineering structures has been developed. Fundamental data for calculating costs also have been presented. Based on the model and data proposed, the trends in the variation of LCC according to the design parameters were examined and the most important design parameters in the LCC analysis of railway track were investigated. The results show that the proportion of renewal and operational costs is much higher in the ballasted track than in the concrete track, and the annual traffic volume and ballast taming period are most significant factors on the LCC of the ballasted track. On the contrary, it is revealed that the proportion of the initial construction costs in the concrete track is much higher, and the LCC of the concrete track is less sensitive to the traffic volume, train speed, and axle load.

Life Cycle Cost Model for Considering Fleet Utilization in Early Conceptual Design Phases

Cost prediction is commonly used when making decisions during the product development process. Oil and gas service companies must consider all life cycle costs for their business models. In addition to capital and operational expenditures, consideration of product utilization is essential. The cost of product failures, maintenance and repairs greatly impact the overall cost model. This paper describes an approach for simulating service availability and corresponding necessary fleet sizes based on existing life cycle cost models. A detailed case study presents the model viability and highlights key leverage points for cost reductions.

Machining Equipment Life Cycle Costing Model with Dynamic Maintenance Cost

This paper presents how a Life cycle cost or Total cost of ownership analysis has been performed on machining equipment in a Swedish company. Life cycle cost models used in case studies are compared to an empirical model, used at the company, where dynamic energy, fluid, and maintenance cost are included. Linear and variable factors in the models are analyzed and discussed regarding data availability and estimation, especially with emphasis on maintenance. The life cycle cost aspect of the equipment give guidelines to consider operation, maintenance, tools, energy, and fluid cost in addition to acquisition cost, when designing/specifying the equipment.

Lifecycle Costs for Energy Equipment: FMECA & Lifecycle Costing Models as “Decision Making” Tools for Cost Reduction During the Whole Equipment Life

The economic crisis created the need to change the management approach on big energy construction projects. In order to reduce costs it is necessary to understand that the price to buy and install energy equipment is only the “top of the iceberg” compared to all costs that occur during the whole life cycle. The studies analyses two PLM (product lifecycle management) models/approaches that represent good management tools and help to reduce lifecycle costs. The two tools, although they do not provide precise results, are actually very appropriate because they allow choosing the cheapest variant to minimize lifecycle costs. In other words, they do not tell how much the costs will actually be but they allow choosing the cheapest option out of a number of alternatives.