• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2007년도 동계학술발표대회 논문집
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• pp.629-634
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• 2007

The Alternative energy has lately attracted considerable attention due to the high oil price and environment problem. In this study, field test of facility for using the geothermal energy source from water-purifying device was constructed and monitoring devices are installed to estimate the efficiency of this system. Initial installation cost can be saved efficiently by connecting a heat pump system into the existing pumping well in site of water-purifying in Cheongju. One set of monitoring results during summer was presented and analyzed.

• 에너지공학
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• 제15권3호
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• pp.160-165
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• 2006

지열원 히트펌프 시스템은 난방과 냉방부분에서 두드러진 관심을 보이고 있다. 국내에 설치된 지열원 히트펌프 시스템의 대부분은 수직형 방식으로 연구대상 또한 수직형이 주류이다. 본 연구에서는 수평형 지열원 시스템을 시설하우스에 설치하여 성능을 조사하였다. 연구결과, 히트펌프만 고려한 난방성능계수는 3.64이고 지열순환펌프를 포함한 성능계수는 3.31로 나타났다. 응축기 제거열에 대한 순환펌프의 동력은 28.0 W/kW이고, 열교환기길이는 53.3m/kW였다. 지중으로부터의 평균채열량은 14.58 W/m이고, 응축열에 대한 열교환기가 매립된 트렌치길이는 27.7m/kW였다.

• 설비공학논문집
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• 제21권5호
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• pp.267-272
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• 2009

This study aims to investigate and analyze the present state of ground source heat pump(GSHP) system applied in Korea. It is based on the statistic from the New and Renewable Energy Center in Korea and construction results of the professional companies registered to the center. The research items were installed area, installed year, building use, ground heat exchange type and heat exchanger type of the pump. According to the result of investigation, the using GSHP system have been increasing steadily as the space heating and cooling system in a building. The capacity of this system is also becoming lager based on technical and economical feasibility analysis about the system since GSHP system first introduced in 2000.

• 한국지열·수열에너지학회논문집
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• 제15권3호
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• pp.14-20
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• 2019

In this study, the technologies and regulations for distributing standing column well(SCW) ground source heat pump systems to the residential cluster homes were investigated. They have only been installed in the public or commercial building having different load pattern and site structure compared with the residential cluster homes. Some of SCWs for the residential cluster homes should be installed under the basement due to a lack of site area. There are pressure differences between the SCWs installed under ground surface and basement. It is needed to develop the technology or devices to prevent overflow caused by pressure difference among the SCWs. In addition, heat balance algorithm between SCWs should be adopted to maximize the system efficiency. A heat pump having heating, cooling, hot water, heating-hot water, and cooling-hot water modes should be developed for adopting an individual air-conditioning system to the residential cluster homes.

• 설비공학논문집
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• 제24권2호
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• pp.196-203
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• 2012

Energy foundations and other thermo-active ground structure, energy wells, energy-slab, and pavement heating and cooling represent an innovative technology that contributes to environmental protection and provides substantial long-term cost savings and minimized maintenance. This paper focuses on earth-contact concrete elements that are already required for structural reasons, but which simultaneously work as heat exchangers. Pipes, energy slabs, filled with a heat carrier fluid are installed under conventional structural elements, forming the primary circuit of a geothermal energy system. The natural ground temperature is used as a heat source in winter and a heat sink in summer. The geothermal heat pump system with energy-slab represented very high heating and cooling performance due to the stability of EWT from energy slab. However, the performance of it seemed to be affected by the atmospheric air temperature.

• 조명전기설비학회논문지
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• 제29권1호
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• pp.47-56
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• 2015

Energy consumption in buildings is currently a real problem. That is why both assessment of energy performance and effective energy management including renewable energy system are essential. Thus, this paper focuses on a case study to analyze the energy performance and cooling & heating energy saving of a large scale shopping store in Daejeon city. The reference building is simulated by using TRNSYS dynamic simulation tool to examine its annual energy consumption. For annual energy analysis of building, one year energy consumption is surveyed in the field. The related study is carried out in large scale shopping store to investigate the energy consumption and energy use trend of heating, cooling, hot water, lighting, ventilation, equipments and other. The evaluation of energy performance of the geothermal heat pump system installed in a large scale shopping store is also analyzed by TRNSYS tool. From simulation results, it evaluated that the geothermal heat pump system is effective energy savings method in large scale shopping store.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2009년도 추계학술대회 논문집
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• pp.567-570
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• 2009

The present study conducted comparative evaluation of wet dry floor heating systems using geothermal heat pump. Circulation hot water from geothermal heat pump which is $10{\sim}15^{\circ}C$ lower than that from boiler was used. In order to access indoor temperature ($25^{\circ}C$) it took 74 minutes for dry type and 247 minutes for wet type. Average floor temperature was $23.89^{\circ}C$ for wet type and $32.66^{\circ}C$ for dry type. Energy saving rate gradually increased by 66% after 138 minutes. In the results, for floor heating system using low temperature circulation water, wet type was not enough to meet stable and comfortable radiant floor heating due to low floor temperature and access time to indoor set temperature. While dry type was practicable for stable floor heating due to fast rise of indoor set temperature and comfortable floor temperature.

• 한국태양에너지학회 논문집
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• 제27권2호
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• pp.11-17
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• 2007

This study evaluates the seasonal performances of the horizontal-type geothermal heat exchanger(HGHEX) installed into the foundation slabs of the complex building located at Seoul. The geothermal system is consisted with totally 31,860m long HGHEX, 16 GSHPs (Ground-source Heat Pump) and 8 circulation pumps. This system supplies cooling and heating to the lobby(F1) and the common spaces(BF1). The average heat exchange temperature differences are $2.7^{\circ}C\;and\;2.5^{\circ}C$ in the summer, $1.5^{\circ}C\;and\;0.5^{\circ}C$ in the winter for the F1 and BF1 respectively. From these results, approximately 400Gcal and 180Gcal of geothermal energy are assumed to have been used during the summer and winter seasons respectively. As a conclusion, the geothermal system is reviewed as a effective utility for heating and cooling at the point of seasonal performances.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2010년도 춘계학술대회 초록집
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• pp.168.2-168.2
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• 2010

The growing market for geothermal heat pump system requires great consideration of quality control and assurance in design and construction. The borehole heat exchanger of GHP system should be sustainable, economical and ecological. Thermal Response Test (TRT) is a useful method for site investigation to obtain reliable data for a optimal system design from the technical and economical aspect. Intensive researches combined with exchange of experiences on an international level within the IEA ECES Annex 21 improved the technology. Major subjects on the interpretation of TRT are development of improved evaluation models, evaluation of the TRT with respect to geological layers and investigation of the influence of ground water. Current status of TRT in South Korea, as well as a new version of the Korean TRT standard test procedure was presented. TRT is mostly used for governmental supported projects with corresponds to more than 100 GCHP systems per year. More than 200 tests are applied, mostly on single U-tube heat exchangers (about 95%). Bentonite is the most common grouting to be used. KIGAM (Korea Institute of Geoscience & Mineral Resources) is also keeping a GIS geological and geothermal database. In the institute also laboratory measurements of rock properties are carried out. About 90% of the laboratory measurements of the rock heat conductivity shows higher values than the in-situ TRT.

• 한국지열·수열에너지학회논문집
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• 제12권2호
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• pp.1-6
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• 2016

A ground air heat exchanger (GAHX), also called earth air heat exchanger is a useful technology to be integrated with other renewable energy technologies. In this study, ground-air heat exchanger system for the air source heat pump is introduced. The purpose of this study is to design the volumetric flow rate and the length of GAHX system. A GAHX length model equation has been developed and used for calculation. GAHX thermal efficiency are recommended as 75% and 85% in order to optimize pipe length. $2,750m^3/h$, $2,420m^3/h$ of volumetric flow rate on 88.3m, 111.7m length are suggested for providing 7.5kW thermal capacity. And the number of path is recommended more than two to minimize pressure drop. For future study, advanced model equation study with ground thermal behavior and a more efficient GAHX design will be considered.