Life-cycle Cost Analysis Techniques Research Articles

Economic analysis of data center cooling strategies

Advancements in information technology have led to an increasing demand for data centers (DCs), and the energy consumption of DCs has gained attention worldwide. Many researchers have attempted to develop efficient DC cooling systems to reduce the energy required for cooling DCs, however, there are limitations in identifying the effect of such systems from the economic perspective. Subsequently, project owners find it difficult to decide whether to apply these systems to their particular DCs. The present research aims to analyze the economic performance of seven cooling strategies developed by the combinations of widely used DC cooling systems. The economic performance of each strategy is estimated by the life cycle cost analysis technique, and the analysis results show that Strategy 5 (A2_M: air-side economizer and supplementary cooling by a mechanical system) yields economic benefits of 26.84% in comparison to the conventional cooling system. The proposed research methodology and obtained results are expected to aid project owners in making effective decisions regarding the selection of an appropriate cooling strategy from an economic perspective.

A Study on Development of a Cost Optimal and Energy Saving Building Model: Focused on Industrial Building

This study suggests an optimization method for the life cycle cost (LCC) in an economic feasibility analysis when applying energy saving techniques in the early design stage of a building. Literature and previous studies were reviewed to select appropriate optimization and LCC analysis techniques. The energy simulation (Energy Plus) and computational program (MATLAB) were linked to provide an automated optimization process. From the results, it is suggested that this process could outline the cost optimization model with which it is possible to minimize the LCC. To aid in understanding the model, a case study on an industrial building was performed to outline the operations of the cost optimization model including energy savings. An energy optimization model was also presented to illustrate the need for the cost optimization model.

Comparing Life-Cycle Cost Analysis of Full-Depth Reclamation Versus Traditional Pavement Maintenance and Rehabilitation Strategies:

Arkansas has highways in the central and southern portions of the state that have experienced unanticipated high traffic levels because of logging and drilling for natural gas. These highways are being exposed to traffic much higher than their design values. In these situations, traditional maintenance and rehabilitation strategies can often be either ineffective or too expensive. Therefore, full-depth reclamation is being explored as a possible alternative for asphalt concrete pavements in Arkansas. This research compared chip seals, overlays, mill and fill, and complete reconstruction with three full-depth reclamation technologies from the economic and structural perspectives: asphalt emulsion, asphalt foam, and portland cement. With life-cycle cost analysis techniques, it was found that the user costs ranged from one-fourth to five times the agency costs. Although full-depth reclamation is economically competitive with traditional strategies, it was not as competitive on roadways with higher ratios of bounded versus unbounded material. Finally, traffic capacity increased significantly at reclaiming depths greater than 10 in. Overall, this research supports full-depth reclamation as a viable economic alternative to chip seals, overlays, mill and fill, and complete reconstruction given the proper conditions of traffic and bound pavement depth.

Glass Selection for High-rise Buildings in the United Arab Emirates Considering Orientation and Window-to-Wall Ratio

This paper is the continuation of a previous paper published by the authors. Both papers are for a study that considers the relationship among the glass thermal characteristics, its cost, and the price of electricity. This paper significantly expands the study by adding commercial buildings typology, considering two major building orientations and taking into account five different window-to-wall ratios. Energy prices and glass prices are also updated. Using the life cycle cost analysis technique, best thermal properties of glass are identified for different design scenarios. Considering that the results can differ with changes in input data, a sensitivity analysis is carried out to understand the impact of changing key input data. The results show that the building typology, orientation, and window-to-wall ratio are not the determining factors for identifying the best glass properties. They also show that the variation in price increase for different glass types is a critical factor in identifying the best glass properties.

Integration of Life-Cycle Cost Analysis with Bridge Management Systems

Many countries use bridge management systems (BMSs), and many of these systems involve some form of life-cycle cost (LCC) analysis. Use of LCC analysis in bridge engineering is rare, however; the technique has been applied primarily in the operation phase to support decisions about bridges that already exist. Yet LCC analysis can be applied across the life of a bridge. This paper introduces the Swedish Bridge and Tunnel Management System (BaTMan). A comprehensive, integrated LCC implementation scheme takes into account the bridge investment and management processes in Sweden. The basic economic analytical tools as well as other helpful LCC analysis techniques are described. A case study demonstrates improvements in BaTMan as a factor in the decision whether to repair or to replace a bridge. Cost records for 1,987 bridges were used as input data in the case study. On the basis of the same records, the average real and anticipated initial costs of various bridge types in Sweden are presented schematically.

Methodology to Review Cost-Effective Highway Sign Retroreflective Sheeting Policy

Kansas State University conducted research for the Kansas Department of Transportation to evaluate their retroreflective sheeting policy. This paper presents a recommended methodology for conducting a life-cycle cost analysis using Kansas cost figures and bid prices for two sheeting types as an example. A 50-state survey uncovered only four states that had ever done an economic analysis of sign sheeting. All were old studies and none used life-cycle cost-analysis techniques. Three types of signs were analyzed. For a new overhead guide sign, signs with high-performance sheeting had an equivalent uniform annual cost (EUAC) of $206.27/sign/year versus $243.40/sign/year for signs with engineering grade sheeting. For overlaying an existing guide sign, the EUAC is $152.2/sign/year for signs with high-performance sheeting versus $178.8/sign/year for signs with engineering grade sheeting. For a ground mounted sign, the EUAC is $4.79/sign/year for signs with high-performance sheeting versus $6.95/sign/year for signs with engineering grade sheeting. It was concluded that Kansas policy of using signs with highperformance sheeting was cost-effective. These conclusions are not necessarily valid in other states, and only two materials were used in the example because valid cost figures were available on only two materials; however, the methodology could be used by all states with appropriate data. An analysis of life-cycle cost results made available by several states would result in a significant contribution to nationwide results on all materials used in the United States under actual conditions. Language: en