• 설비공학논문집
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• 제29권4호
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• pp.202-211
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• 2017

In this study, the exergy that can be reflected in the energetic and economic values was used to assess the heat tariff of a district heating (DH) system instead of the enthalpy. It is difficult to directly apply the exergy to the current heat-charge system because of the complicated calculation; therefore, the difference between the supply and return temperatures was converted to the exergy-temperature difference for the ease of the heat-amount calculation. As a result of the exergy analysis for a DH substation, the exergy-temperature difference did not affect the surrounding temperature and pressure loss. The supply temperature and the maximum difference between the supply temperature and the return temperature exerted the main effect on the exergy-temperature difference. The new heat charge of a DH user was slightly reduced in winter compared with the previous charge, but the heat charges in the other seasons are almost the same. It is concluded from the assessment of the heat tariff for which the exergy is used that this tariff is more feasible for both DH suppliers and consumers compared with enthalpy.

• 자원ㆍ환경경제연구
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• 제10권3호
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• pp.367-386
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• 2001

In this paper we analyze the environmental advantages of district heating system. We construct three econometric models to analyze the energy consumption and economic cost as well as the emission of the major pollutants like $SO_x$, $NO_x$, DUST, and $CO_2$. As the size of heating supply is larger, the district heating system is evaluated to be better than other heating systems environmentally and costly in the long run. Especially, the district heating reduces $SO_x$ emission significantly when the size of heat production is large. But the advantages of district heating system are very sensitive to the fuel mix and heat source.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2008년도 하계학술발표대회 논문집
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• pp.643-649
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• 2008

The purpose of this study is to establish a standard for unit cooling load in central control type apartment applied district cooling. The model of unit household was selected. And the standard of coefficient of overall heat transmission, location of unit household, indoor air temperature, solar radiation & thermal conduction at window and interior load was selected, and region, expansion or non-expansion of balcony, pyeong type, azimuth, rate of window area was applied as parameter. And then cooling load simulation was performed. Based on the result of simulation, the synthetic district cooling load was presented for selecting heat source of apartment applied district cooling, and unit cooling load was analyzed according to design parameter.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2007년도 동계학술발표대회 논문집
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• pp.459-465
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• 2007

This study was conducted to calculate the LCC of a apartment complex with a type of heating system, district heating and cogeneration system. For the purpose of analyzing LCC according to size of apartment complex, 500, 1,500 and 4,000 houses of model apartment selected. This research performs design of heating system and the life cycle cost analysis including an initial cost, energy cost, maintenance and operation cost, replacement cost and renovation cost during the project period(15years). According to the calculated results, 1) Initial cost of cogeneration system with 500, 1500 and 4000 houses is higher than district heating system each of 20%, 13%, 12%. 2) In case of cogeneration system, the payback period by electric generation is 5.21, 4.92 and 4.47 years and saving cost was calculated 29 billion won, 94 billion won and 262 billion won after payback period. 3) Cogeneration system LCC was 1.12, 1.07 and 1.06 times larger than district system with the size of apartment complex. According to the case of this study district heating system is more efficient than cogeneration system in terms of the reduction of LCC. 4) Gas Engine Co-generation System is more efficient than other systems because it can collect progressive part from electric charge progressive stage system. However, the efficiency is decreasing because of raising of fuel bills(LNG) and lowering of power rate for house use. Especially the engine is foreign-made so the cost of maintenance and repair is high and the technical expert is short. 5) District heating is also affected by fuel bills so we should improve energy efficiency through recovering of waste heat(incineration heat, etc.). Also, we should supply district cooling on the pattern of heat using of let the temperature high in winter and low in summer.

• 설비공학논문집
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• 제27권10호
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• pp.544-551
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• 2015

This study was conducted to determine the LCC of apartment complexes with district heating and a cogeneration system. For the purpose of analyzing LCC according to the size of the apartment complex, 500, 1,500, and 4,000-unit model apartments were selected. Analysis was performed on the design of the heating system and the life cycle cost including total construction cost, maintenance and operation cost for the duration of the project period (15 years). According to the calculated results, 1) The initial cost of the cogeneration system for 500, 1,500, and 4,000-unit apartments is higher than that of the district heating system by 20%, 13%, and 12%, respectively. 2) In the case of the cogeneration system, the payback period by electric generation was found to be 5.21, 4.92 and 4.47 years, and saving cost was calculated to be 29 billion won, 94 billion won and 262 billion won after the payback period for 500, 1,500, and 4,000-unit apartments, respectively. 3) The LCC values of the cogeneration system were 1.12, 1.07 and 1.06 times larger than those of the district system according to the size of the apartment complex. In this study, the district heating system was found to be more efficient than the cogeneration system in terms of LCC reduction. 4) District heating is affected by fuel bills, so energy efficiency should be improved through recovering waste heat (incineration heat, etc.). Also, district cooling should be provided according to heat use to keep the temperature high in winter and low in summer.

• 한국기후변화학회지
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• 제8권3호
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• pp.213-220
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• 2017

The purpose of this study is to analyze effects of Greenhouse Gas (GHG) emission reduction in district energy business mainly based on Combined Heat and Power (CHP) plants. Firstly this paper compares the actual carbon intensity of power production between conventional power plants and district energy plants. To allocate the GHG from CHP plants, two of different methods which were Alternative Generation Method and Power Bonus Method, have been investigated. The carbon intensity of power production in district energy plants ($0.43tonCO_2e/MWh$) was relatively lower than conventional gas-fired power plants ($0.52tonCO_2e/MWh$). Secondly we assessed the cost effectiveness of reduction by district energy sector compared to the other means using TIMES model method. We find that GHG marginal abatement cost of 'expand CHP' scenario (-$134/ton$CO_2$) is even below than renewable energy scenario such as photovoltaic power generation ($87/ton$CO_2$). Finally the GHG emission reduction potential was reviewed on the projected GHG emission emitted when the same amount of energy produced in combination of conventional power plants and individual boilers as substitution of district energy. It showed there were 10.1~41.8% of GHG emission reduction potential in district energy compared to the combination of conventional power plants and individual boilers.

• Korean Chemical Engineering Research
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• 제56권6호
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• pp.841-855
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• 2018

본 연구는 도시 내 지역난방 공급지역에 존재하는 Heat Pump용 가용 잠재적 열원을 추정하고자 하였다. 미활용에너지 잠재량은 Open source 기반의 자료를 바탕으로 추정 통합하였다. 특히 수도권 남부에 위치한( 평택시) DH network 내에 대형마트와 공공사우나 시설에 대해 회수 가능한 열에너지 밀도와 열원 지역의 열 수요에 대해 지리적인 공간 분석을 수행하였다. 연구 결과, 연구 대상 DH network 지역에서는 대형마트와 공공사우나 두 가지 열원에 대해 총 1,741.7 toe/year 수준의 잠재 에너지량을 보유하고 있었다. 이 중 57.8%에 해당하는 1,006.9 toe/year를 지역난방용으로 연계할 수 있을 것으로 추정 되었다. 대형마트는 연면적과 에너지 사용량이 0.4937의 양의 상관관계를 보였다. 회수 가능한 에너지 원단위는 상관관계계수를 반영하여 연면적 당 $0.0017toe/m^2$, 저감 가능한 온실가스 배출량은 $0.0069tCO_2/m^2$로 분석되었다. 또한, 공공사우나는 실증사례와 이론 계산 값을 비교하여, 80% 수준의 보수적 추정으로 목욕장 면적당 $0.0315toe/m^2$가 회수 가능한 에너지 원단위로 분석되었으며, 저감 가능한 온실가스 배출량은 $0.1183tCO_2/m^2$로 분석되었다. 이 지역의 총 잠재 에너지량은 행정 구역별 공동주택의 열 수요와 0.5272의 양의 상관관계를 갖고 있었으며, 특히 교통과 상업 중심 지구에서 상대적으로 높은 잠재 에너지량을 가지고 있음을 확인 하였다.

• 에너지공학
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• 제28권4호
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• pp.94-102
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• 2019

본 연구는 집단에너지 사업자들의 최대 열수요가 발생할 때의 열원설비 운영현황을 분석하여, 이를 수익 최대화 관점에서 현재 설치되어 있는 설비의 운영 최적화 방안을 도출하여 제시하고, 도출된 결과를 토대로 해당 열부하에 대한 CHP(Combined Heat and Power), PLB(Peak Load Boiler) 등의 최적 설비용량 구성방안을 제시함으로서 사업자들이 운용상태까지 고려해서 보다 경제적으로 설비투자를 할 수 있는 가이드라인을 제공하고자 하였다.

• 열처리공학회지
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• 제35권4호
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• pp.193-202
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• 2022

Manholes and underground spaces are installed to manage the buried heat transport pipes of the district heating system, and the corrosion damage of the equipment placed in this space often occurs. The purpose of this work is to identify locations with a high risk of corrosion damage in the air vent and to establish preventive measures based on precise analysis via sampling of heat transport pipes and air vents that have been used for about 30 years. The residual thickness of the air vent decreased significantly by reaching ~1.1 mm in thickness, and locations of 60~70 mm away from a transport pipe were the most vulnerable to corrosion. The energy dispersive X-ray spectroscopy (EDS) analysis was performed in the corroded oxides, and it was found that chloride ion was contained in the corrosion products. Anodic polarization tests were carried out on the air vent materials (SPPS250, SS304) with varying the amounts of chloride ions at two different temperatures (RT, 80℃). The higher concentration of chloride ions and temperature are, the lower corrosion resistances of both alloys are.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2010년 춘계학술대회논문집
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• pp.127-128
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• 2010

As P-new-city is planned and constructed, district eating utilizing an existing near-by power plant's waste heat is considered as an economic and environment friendly way of providing heating to the new city. Many pipeline diameters and pumping station location and capacity were assumed, investigated and optimized, to satisfy the customers' heat demand considering common district heating pipe-network design and construction practice, and also and construction, pumping station land price and construction and the pumping energy cost during lifetime of DH systems.