• 청정기술
• /
• 제23권4호
• /
• pp.441-447
• /
• 2017

개념설계 단계에서 개발 공정에 대한 경제적 타당성 분석에 대한 중요성이 대두되고 있으며, 목표 경제성에 부합하는 공정개발을 위한 공정 최적화에 대한 연구도 활발히 진행되고 있다. 발전 시스템 분야에서는 전력 단가(Levelized cost of electricity, LCOE)를 예측하여 경제적 효과를 정량적으로 비교 분석하는 평가 방법이 많이 활용되고 있다. 본 연구에서는 목표 전력 단가에 부합한 발전 시스템을 설계하기 위해서 요구되는 핵심기기의 설계 조건을 역산출 할 수 있는 플랫폼을 구축하였으며 초임계 이산화탄소 발전 시스템이 석탄 화력에 적용될 경우, 목표 전력 단가(초임계 증기 랭킨 사이클 발전 단가, $ 85.4 /kWh)를 충족하기 위해 요구되는 주요 핵심기기(압축기, 터빈, 열교환기) 등의 설계 지표 기준을 도출하였다. 터빈의 등엔트로피 효율이 86%인 경우, 주압축기 효율은 88% 이상 설계되어야 한다. 만약 터빈의 등엔트로피 효율이 88%로 설계된 경우, 주압축기 효율은 82%까지 완화하여 설계가 가능하다. End seal 부분에서 누설량을 0.24% 수준으로 유지하고, 열교환기의 경우 cold side 출구측 온도가 $92{\sim}97^{\circ}C$, 열용량은 2650 ~ 2680 MWth로 설계한다면 목표 전력단가를 충족시킬 수 있을 것으로 확인되었다.

• Journal of Electrical Engineering and Technology
• /
• 제10권4호
• /
• pp.1471-1479
• /
• 2015

A major portion of the capital costs in the present day power transmission systems are due to the cost of equipment and construction process. Transmission utilities in the recent years are drawing greater attention towards performing life cycle costing studies for cost management and decision making. However, the data involved in these studies are highly uncertain and the effect of these uncertainties cannot be directly included in the study process, resulting in inaccurate solutions. Interval mathematics provides a method for including these uncertainties throughout the cost analysis and provides final solution range in the form of intervals. In this regard, it is essential and extremely important that significant research has to be carried out in understanding the principles of life cycle costing methodology and its applicability to cost analysis of transmission lines along with uncertainties involved in the cost assessment process. In this paper, economic analysis of power transmission lines using interval mathematics has been studied. Life cycle costing studies are performed using net present value analysis on a range transmission lines used in India and the results are analyzed. A cost break even analysis considering right of way costs was carried out to determine the point of economy indifference.

• Nuclear Engineering and Technology
• /
• 제43권2호
• /
• pp.141-148
• /
• 2011

This paper presents the quantitative analysis results of research on the burnup effect on the nuclear fuel cycle cost of BeO-$UO_2$ fuel. As a result of this analysis, if the burnup is 60 MWD/kg, which is the limit under South Korean regulations, the nuclear fuel cycle cost is 4.47 mills/kWh at 4.8wt% of Be content for the BeO-$UO_2$ fuel. It is, however, reduced to 3.70 mills/kWh at 5.4wt% of Be content if the burnup is 75MWD/kg. Therefore, it seems very advantageous, in terms of the economic aspect, to develop BeO-$UO_2$ fuel, which does not have any technical problem with its safety and is a high burnup & long life cycle nuclear fuel.

• Nuclear Engineering and Technology
• /
• 제54권3호
• /
• pp.877-887
• /
• 2022

A new reactor concept is described that directly couples a supercritical CO₂ (sCO₂) power cycle with a CO₂-cooled, heavy water moderated pressure tube core. This configuration attains the simplification and economic potential of past direct-cycle sCO₂ concepts, while also providing safety and power density benefits by using the moderator as a heat sink for decay heat removal. A 200 MWe design is described that heavily leverages existing commercial nuclear technologies, including reactor and moderator systems from Canadian CANDU reactors and fuels and materials from UK Advanced Gas-cooled Reactors (AGRs). Descriptions are provided of the power cycle, nuclear island systems, reactor core, and safety systems, and the results of safety analyses are shown illustrating the ability of the design to withstand large-break loss of coolant accidents. The resulting design attains high efficiency while employing considerably fewer systems than current light water reactors and advanced reactor technologies, illustrating its economic promise. Prospects for the design are discussed, including the ability to demonstrate its technologies in a small (~20 MWe) initial system, and avenues for further improvement of the design using advanced technologies.

• 국제학술발표논문집
• /
• The 2th International Conference on Construction Engineering and Project Management
• /
• pp.30-40
• /
• 2007

The demand for light-rail construction projects has recently been increasing, and they are mostly supervised by private construction companies. Therefore, a private construction company that aim to raise gains from the operation of the facilities during the contract period greater than what they invested should b able to accurately calculate the costs from the aspect of Life Cycle Cost (LCC). In particular, a light-rail transit bridge that has a heavier portion from the aspect of the cost of light-rail transit construction requires a more accurate calculation method than the conventional LCC calculation method. For this, an LCC analysis model was developed and a cost breakdown structure was suggested based on literature review. The construction costs by shape of the upper part of a light-rail transit were calculated based on the cost breakdown system presented in this paper, and the cost generation cycle and cost unit price were collected and analyzed based on records on maintenance costs, rehabilitation and replacement. In addition, after forming some hypotheses in order to perform the LCC analysis, economic evaluation was conducted from the aspect of the LCC by using performance data by item.

• 한국연소학회:학술대회논문집
• /
• 한국연소학회 2012년도 제45회 KOSCO SYMPOSIUM 초록집
• /
• pp.225-228
• /
• 2012

Thermodynamic and economic analysis on various type of gas turbine combined cycle power plants was presented to build up the criteria for optimization of power plants. The efficiency considered about energy level difference between electricity and heat was introduced. The efficiency on power and heat generation of power plants whose have different purpose was estimated and power generation costs on various type of combined heat and power plants : fired/unfired, condensing/non-condensing mode, single/double pressure HRSG.

• 한국건축시공학회:학술대회논문집
• /
• 한국건축시공학회 2015년도 추계 학술논문 발표대회
• /
• pp.192-193
• /
• 2015

Construction Cycle Trend Survey, which survey total value of orders and realized amounts monthly, is a valuable statistics that used to quick grasp or forecast the trend of domestic construction business. In recent periodical survey quality diagnoses, few professional users named a problem that Construction Cycle Trend Survey could not get together with the current state of the construction industry. This study examined weather Construction Cycle Trend Survey reflects the economic sentiment of construction business or not. Paired t test was performed between Construction Cycle Trend Survey and Construction Business Survey Index (CBSI), and significant differences were verified.

• 한국도로학회논문집
• /
• 제18권3호
• /
• pp.33-45
• /
• 2016

PURPOSES : Concrete pavement has been used in the construction of the Jungbu expressway in 1987. More than 60% of the pavement on the expressway is currently made of concrete, but most has been used far beyond their design life. Pavement life has been extended through routine maintenance or overlay. However, the structural capacity of the pavement has reached its limit, and extensive rehabilitation/reconstruction with long time traffic blocking should be considered. The three following issues on concrete rehabilitation/reconstruction will be discussed: (1) economic comparison of asphalt inlay and asphalt overlay, (2) economic comparison preventive overlay on a section which is currently good and routine overlay on the section which will be poor, and (3) economic analysis of early-strength concrete when it is used in concrete reconstruction. METHODS : First, various life cycle cost analysis tools were compared, and the proper tool for the extensive rehabilitation/reconstruction was selected. Second, a sensitivity analysis of the selected tool was performed to find the influential input variables, which should be carefully selected in the analysis. Third, three case studies, which can be issues in the rehabilitation/reconstruction of the expressway concrete pavement in Korea, were performed. RESULTS : Asphalt overlay without milling the deteriorated concrete showed 18~25% lower life cycle cost than the current asphalt inlay with milling. The good current preventive overlay on the section was economically justified within the scope of this study. The construction cost limit of the early strength concrete was suggested to be economical for 1, 3, and 7 days of construction alternative opening. CONCLUSIONS : CA4PRS was a viable tool for comparing various rehabilitation/reconstruction issue alternatives. Several concrete issues associated with the rehabilitation/reconstruction of the deteriorated concrete pavement were discussed as mentioned above.

• Korean Chemical Engineering Research
• /
• 제47권1호
• /
• pp.65-71
• /
• 2009

본 연구에서는 상용모사기를 이용하여 100 MWth 매체순환연소(CLC) 복합발전 플랜트의 성능 및 경제성 평가를 수행하였다. 원료로는 천연가스와 합성가스를 고려하였으며 원료에 따른 성능 및 발전단가를 비교, 분석하였다. 천연가스와 합성가스를 사용하는 경우 모두 발전 효율은 53~54% 수준으로 평가되었으며 이는 기존 연구와 부합하는 결과임을 확인하였다. 경제성 분석을 위해서 Chemical Engineering Plant Cost Index와 Guthrie 방법을 사용하여 장치비를 산정하였으며 합성가스의 저위발열량이 천연가스보다 낮기 때문에 장치비가 다소 높은 것을 확인하였다. 연료의 종류에 따른 발전단가 계산 결과 합성가스의 가격이 5.3 $/GJ 정도 되는 경우에 천연가스를 이용하는 경우의 발전단가인 5.8 ¢/kWh보다 낮아지는 것으로 나타났다.

• 한국철도학회:학술대회논문집
• /
• 한국철도학회 2011년도 춘계학술대회 논문집
• /
• pp.1313-1320
• /
• 2011

World Business Council for Sustainable Development(WBCSD) is effort to achieve sustainable development in economic growth, environmental preservation and social development. Being this way, it is essential for developing evaluation tool which quantify to fulfill sustainable development. Eco-efficiency is one of the quantitative tools to evaluate environmental impact and economic aspect. Eco-efficiency, in general term, means creating more value of product or services with less impact to environment. It indicates as environmental impact in denominator and value of product or services in numerator. Eco-efficiency shows how much economic value reveals to unit environmental impact caused by product or service as an indicator. This study aims at developing eco-efficiency indicator of railway industry considering use stage among the entire life cycle stage of KTX and Saemaul train and also, figure out eco-efficiency value through indicator. Therethrough, it is enables to evaluate created value per environmental aspects. Since rail vehicles demands a lot of energy to transport people during use stage, the environmental impact is more significant than other lkfe cycle stages. Therefore, it quantified environmental indicator as CO2 emission and economic indicator as transportation record per a year with an annual income. This study contributes to be used as a tool for quantifying indicator of comparison evaluation in respect of rail vehicle in use stage.