Total life cycle costs

In considering the economics of process alternatives, it is important to think about the total life cycle costs. There is an increasing interest in this concept in the environmental area, with a recognition of the need to incorporate waste treatment, waste disposal, regulatory compliance, potential liability for environmental damage, and other long term environmental costs into project economic evaluation. Similarly, we must consider life cycle safety costs. Some examples of factors which should be considered include ... 

Barriers to the increased usage of rubber in asphalt pavements are both economic and noneconomic in nature. The cost of installing roads of rubberized asphalt is greater than conventional asphalt, which is an economic barrier. On the other hand, several studies show that the total life cycle cost of rubberized asphalt is... 

Levelized Life Cycle Cost - A total life cycle cost divided into equal amounts. 

Step 5 of the master planning process involves performing both an economic and a qnalitative assessment of the alternative plans of action. The economic evalnation shonld consist of a time-valne-of-money assessment of the total life-cycle costs of competing alternative plans of action. The qnalitative assessment of alternatives reqnires that the alternatives be snbjectively compared on snch attributes as personnel safety, flexibility, ease of implementation, maintainahitity, potential product damage, and so forth. 

Plastic piping [polyvinyl chloride (PVC)] does not show corrosion as in the case of metal piping, but the properties of plastic piping deteriorate over time. In severely corrosive soils PVC piping may be selected rather than a metallic piping because it is inert to the chemical conditions. PVC has a lower density than steel and iron and hence it is relatively easy to handle in the field. However, PVC has lower strength and traditional welding is not possible. PVC has been used for a relatively short time, compared with steel and iron water lines. Thus, there is limited data on the expected service life of PVC pipelines, and calculations of comparative total life-cycle costs are not possible. 

Conventional structures, such as a bridge or a civil aircraft, are still commonly passive structures. These structures are designed to withstand the maximum expected loads, even in the presence of small cracks that may occur in service, due to corrosion, impacts with external objects or any other reason. The maximum crack size before catastrophic failure can be predicted, and the detectable crack size (of course, much smaller than the critical size), are defined according to the available non-destructive methods also the crack growth by dynamic loads can be predicted. Therefore, the time between inspections can be defined to avoid any incipient but undetected crack to become critical. This is the so called maintenance on schedule , and it has proven to be a very safe method - presently the percentage of aircraft accidents due to structural failure is very low. But the cost of these inspections is high, because they require sophisticated NDl and many labour hours. The cost of maintenance is about a quarter of the total life-cycle costs of an aircraft, similar to the fuel, crew, or acquisition costs. 

Three different criteria have been used in order to assess the optimum designs achieved through the above mentioned formulations The initial construction cost the total life-cycle cost and the torsional response criterion. Eor the second and third assessment criteria, ground motions chosen from the Somerville and Collins (2002) database, belonging to 50/50, 10/50 and 2/50 hazard levels (see Table 7), were used. 

In this chapter, structural optimization is considered for the assessment of (i) the behaviour factor q with respect to limit state fragiHties and (ii) the minimum torsional response of RC buildings under different design considerations in three hazard levels (frequent, occasional and rare). The designs were assessed with respect to the initial as well as to the total life-cycle cost. From the present study the following conclusions can be drawn ... 

T able 13.2 Consulting fees are typically a very small fraction of the total life-cycle cost for an engineered project as suggested by this hypothetical accounting of costs. 

From this upper echelon list, the firm matches key suppliers with high-impact categories and chooses a small number of partners to participate in a disciplined, systematic supplier relationship management (SRM) effort. These partners meet with the buying firm and establish a mission or strategic purpose for the SRM effort. The focus then moves to analyzing the total cost of ownership (or total life cycle costs) and finding the hidden cost reduction opportunities and extra values in the relationships. 

The design of products can have a significant impact on supply chain complexity. It can be argued that the supply chain begins on the drawing board in that decisions on the choice of materials and components can directly or indirectly impact total life cycle costs as well as agility and responsiveness. 

Lithium-ion battery technology is being introduced into power supplies used by the US Armed Forces for a variety of applications, including land (such as portable systems, small vehicles, and communication) marine (submarines and imderwater vehicles) air (unmanned aerial vehicles [UAVs]), and space (satellites and space ships) uses. In many cases, the same cells and design parameters that support coimnercial battery packs are used in military battery packs. This approach is expected to result in a major decrease in the total life cycle cost of the equipment these batteries support. Besides cost, military applications have special requirements for lithium-ion batteries ... 

The total life-cycle costs presented in Figure 7.9 were generated using a present value (PV) factor of 14.32 (20 years, 6% interest rate, and 2.5% inflation rate). They vary from 0.45/m for small plants to 0.20/m for large plants. Total life-cycle costs are smallest for the CAS plants, followed by MBR and CAS-TF plants. The premium for a membrane-filtered wastewater over CAS is 5-20% and increases with plant size. 

The breakdown of costs for the ultrafiltration option is presented in Figure 7.10. Figure 7.10a shows that UF pretreatment only represents about 10% of the total life-cycle costs and that energy accounts for one third of the costs. Figure 7.3b shows a breakdown of the total energy cost (3.46 kWh/m ), with UF accounting for only 5% of the total. 

Figure 7.10 Cost breakdown for seawater desalination with ultrafiltration pietieatment (a) Total life-cycle cost ( indicates a capital cost) and (b) energy cost (total 3.46 kWh/m ).

Figure 7.11 Impact of RO flux on total life-cycle costs of a seawater desalination system.

Increased RO Recovery Figure 7.12 shows that total life-cycle costs decrease as recovery increases all the way to 50%. The benefit is derived from building a smaller intake and pretreatment system. At recovery higher than 50%, higher energy costs outweigh these benefits. 

Ultrafiltration pretreatment positively protects an RO desalination system, and thus has the potential to increase plant availability and reliability. In addition, the analysis presented above shows that UF pretreatment offers the possibility to optimize the design and operation of RO systems to reduce total life-cycle cost below current practice. 

The total life-cycle costs for producing RO water from secondary effluent and seawater are 0.28US /m and 0.62US /m, respectively, a ratio of 2.2. 

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