• 한국건설관리학회논문집
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• 제14권5호
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• pp.3-11
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• 2013

정부에서는 국가정책 아젠다인 '저탄소 녹색성장'을 실현시키기 위한 노력들을 전산업부문에 걸쳐 진행하고 있다. 건설산업 부문도 예외가 아니어서 에너지 및 온실가스 배출저감을 위한 기술개발이 활발히 이루어지고 있으며 특히, 건축물은 국가 총에너지소비의 20% 이상을 차지하고 있어 주거건물의 에너지 효율화 및 이산화탄소 배출량 저감은 국가적으로 시급한 과제라 할 수 있다. 또한 최근 사회적으로 이슈화되고 있는 주택전세난으로 서민들의 고통이 가중되고 있어, 시장수요에 능동적으로 신속하게 대응할 수 있는 주택생산시스템이 요구되고 있다. 이에 본 연구에서는 친환경적이고 시공 효율성을 극대화시킬 수 있는 시스템을 구축하기 위해 국내 유닛 모듈러 주택생산체계를 조사 분석하여 문제점을 찾아내고 이에 대한 개선안을 제시함으로써 유닛 모듈러 주택의 활성화 기반을 위한 제시하고자 한다.

• 설비공학논문집
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• 제15권5호
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• pp.360-371
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• 2003

The calculation of each unit cost of productions is very important for evaluating the economical efficiency and deciding the reasonable sale price. In the present, two methods of exergy costing on multiple energy systems are suggested to reduce the complexities of conventional SPECO method and MOPSA method and to improve the calculation efficiency of exergoeconomics. The suggested methods were applied to a gas-turbine cogeneration and the unit costs of the power and the steam energy were calculated as an example. The main points of our methods are the following three. First, one exergetic cost is applied to one cycle or system. Second, the suggested equations are the internal cost balance equation and the production cost balance equation. Third, necessary states in a system are only inlet and exit states of 1ha components producing energy.

• KIEAE Journal
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• 제10권4호
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• pp.101-109
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• 2010

As global warming progresses, nations around the world are trying to reduce emission of $CO_2$ that accounts for the greatest portion of greenhouse gases. To reduce $CO_2$ emission, it is first necessary to estimate $CO_2$ emission of each industry. Government authorities estimate basic unit of $CO_2$ emission from re-bar that is one of the key materials of construction industry with LCA technique (Life Cycle Assessment). However, basic unit of $CO_2$ emission varies from organization to organization. The Ministry of Land, Transport and Maritime Affairs (2004) publishes it 3.48($TCO_2/ton$) and 0.30($TCO_2/ton$) with input-output analysis while the Korea Environmental Industry & Technology Institute (2008) defines it as 0.34($TCO_2/ton$) with process analysis, which indicates ambiguity in application of basic unit of $CO_2$emission. Based on the analysis of conventional methods used for estimating the $CO_2$ emission, therefore, this research suggests existing problems on the methods and focuses on proposing an strategy to effectively estimate the basic unit of $CO_2$ emission according to the energy consumption limited to the re-bar production in steel mill in order to overcome the problems. The result of this research is expected to be helpful in calculating and reducing $CO_2$ emission.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2010년도 춘계학술대회 초록집
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• pp.228.2-228.2
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• 2010

In this work, the hydrogen production costs of the nuclear energy sources are estimated in the necessary input data on a Korean specific basis. G4-ECONS was appropriately modified to calculate the cost for hydrogen production of HTE process with Very High Temperature nuclear Reactor (VHTR) as a thermal energy source rather than the LUEC (Levelized Unit Electricity Cost). The general ground rules and assumptions follow G4-ECONS. Through a preliminary study of cost estimates, we wished to evaluate the economic potential for hydrogen produced from nuclear energy, and, in addition, to promptly estimate the hydrogen production costs for an updated input data for capital costs. The estimated costs presented in this paper show that hydrogen production by the VHTR could be competitive with current techniques of hydrogen production from fossil fuels if $CO_2$ capture and sequestration is required. Nuclear production of hydrogen would allow large-scale production of hydrogen at economic prices while avoiding the release of $CO_2$. Nuclear production of hydrogen could thus become the enabling technology for the hydrogen economy. The major factors that would affect the cost of hydrogen were also discussed.

• 설비공학논문집
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• 제21권5호
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• pp.311-318
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• 2009

In previous study, a new allocation methodology of common cost on multi-product have been suggested. The aim of this study is to suggest the methodology that allocates an environment pollution cost including carbon emission cost to each cost of multi-product. For this study, a supposed multi-energy system composed of twenty kinds of systems was made. The multi-energy system produces eighteen kinds of outputs that are electricity, steam, hot water, chilled water, ice, warm air, and cooling air from seven kinds of energy source that are LNG, coil, geothermal energy, sun heat, hydrogen, bio-mass, and waste. The new methodology was applied to the multi-energy system in order to allocate the environment pollution cost to each production cost, and twenty seven equations were induced. From this result, it is concluded that this methodology can estimate each unit cost and allocate each cost flow in any product of any energy system.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2005년도 춘계학술대회
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• pp.223-226
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• 2005

For $CO_2-free$ hydrogen production and better utilization of the produced carbon, catalytic decomposition of methane over rubber-grade carbon blacks manufactured from coal tar was carried out. The catalytic activities of several domestic carbon blacks were compared. A pelletized carbon black exhibited considerably lower activity and activation energy than the fluffy( loose) carbon black of the same grade. This difference is considered due to the binder that was added during pelletization. For pelletized carbon blacks, a tendency was observed that the activity per unit mass of catalyst increased with the specific surface area of the carbon black. Another tendency was also observed that the activation energy increased with the primary particle size or decrease of the specific surface area.

• 한국환경과학회지
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• 제22권3호
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• pp.269-279
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• 2013

In this paper, an environmental assessment was carried out on the whole process of industrial business activities to establish a basic plan for climate change mitigation and energy independency. The whole process was divided into each discharge process in terms of water, air, solid waste, green house gases and refractory organic compounds. The flowcharts and basic unit of process were analysed for three years (2008-2010), being utilized as basic information for the life cycle assessment. It was found that the unit loading for the whole process significantly depends on changes in the operation rate change and highly concentrated wastewater inflow. About 35% of solid waste production was reduced by improving the incineration method with co-combustion in coal boiler, generating about 57% of electricity used for the whole process, and consequently reducing the energy costs. As the eco-efficiency index was found to be more than 1, compared to the previous years, it can be said that improvement in general has taken place.

• 한국태양에너지학회 논문집
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• 제39권1호
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• pp.67-76
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• 2019

A ground source heat pump (GSHP) system can stable system operation by using underground heat source and has high reliability for energy production. However, wide-spread of the GSHP system is delayed to high initial investment costs. In previous studies, horizontal and unit-type ground heat exchanger (GHX) have developed to overcome disadvantages such as high initial cost. However, these performances of GHXs are greatly influenced by climate and weather conditions. It is necessary to analyze the performance of GHX according to the ground temperature change in the installation site. In this study, the ground temperature of each installation site confirmed and performance of unit-type GHX quantitatively analyzed by numerical analysis. As the result, the performance of the unit type GHX was 33.9 W/m in Seoul, 34.2 W/m in Daejeon, and 37.2 W/m in Busan.The result showed the difference performance of GHX according to local climate was maximum of 9.7%.

• 대한기계학회논문집
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• 제16권12호
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• pp.2368-2375
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• 1992

본 연구에서는 축대칭 유동장치를 구성하여 열선 풍속계를 이용, 중심축에 따 른 난류쇠퇴양식을 살펴보고 동시에 난류에너지천이에 대한 세밀한 분석을 통하여 각 각 상류유동전개부, 수축부 및 자유분사류로 연속되는 3개의 유동 구조속에서 어떻게 천이해 갈 것인가를 측정하여 축대칭 유동의 난류구조 변천에 대한 기초 실험자료로 제시하고저 한다.

• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2008년도 추계학술발표대회 논문집
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• pp.322-326
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• 2008

This paper presents an estimation method of small hydro power(SHP) potential using a SHP resource map. As a basic unit of SHP energy potential at a certain area, capacity and annual energy production of unit head was calculated from the catchment area given by a SHP resource map which was established by numerical hydrologic simulation so that a logical and relatively accurate potential estimation was possible comparing with the performance analysis model for SHP sites. The performance characteristics for Samok-Ri site were analyzed, using the SHP resource map and the developed model. It was found that the SHP resource map and the developed model is useful tool to estimate SHP potential.