• 한국지열·수열에너지학회논문집
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• 제12권2호
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• pp.7-12
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• 2016

This study have an objective to suggest basic data and measured result of heating performance on water-water type horizontal geothermal heat pump which is based on heating and cooling load calculation result of small residential house. The average temperature during measured periods is $9.4^{\circ}C$ on primary EWT and is $7.6^{\circ}C$ on primary LWT. The temperature difference shows $1.8^{\circ}C$ as average temperature. Because the average outdoor temperature of peak is lager than on December and than on January, the temperature difference between EWT and LWT is bigger that on January than that on December. The system COP is 3.62.

• Journal of Biosystems Engineering
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• 제37권1호
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• pp.19-27
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• 2012

Purpose: Utilizing air thermal energy during over-heated time in the greenhouse is a necessary component to save greenhouse heating costs for nighttime. However, there is no practical way to implement the related principles. Methods: In this study, a heating and cooling system which utilizes the surplus air thermal energy in a greenhouse was developed. Available air thermal energy and heating load for this experimental glasshouse were estimated based on temperature conditions of the plant growth and weather data. Results: Estimated values were 400 MJ/day for maximum surplus air thermal energy and 340 MJ/day for maximum heating energy which were target values of the design as well. The system consists of a heat pump, fan-coil units and heat storage tanks which are divided into low and high temperature tanks. Moreover, a new control logic was developed for surplus air thermal energy utilization. Conclusions: This paper explains the details of conceptual design process of the system. Results of test operations showed that the developed system performed the recovery and supply of the thermal energy according to design purposes.

• 설비공학논문집
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• 제30권4호
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• pp.167-174
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• 2018

The geothermal heat pump systems were installed for heating and cooling of public buildings in Jincheon Eco-friendly Energy town. The heat pump system was operated at night to save on operational costs, and the cold heat was stored in thermal energy storage (TES). In this study, the performance of geothermal heat pump systems with the TES during the summer season was analyzed, and the operational costs with and without the TES were compared. The electric chiller model was used to simulate a heat pump applied without the TES system. Electric rates of each system were measured to calculate operational costs. When the TES is used in the air conditioning system, the electric load (30.4 MWh) calculated in the daytime can move to off-peak load time, and the operational cost is reduced by 36~54%.

• 한국전자통신학회논문지
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• 제14권2호
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• pp.361-368
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• 2019

본 논문은 전기차 기반의 1톤급 상용차용 통합공조 시스템에 관한 연구이다. 전기 상용차의 경우 화물의 승하차를 위해 문의 개폐가 빈번하게 이루어지기 때문에 열손실이 크게 발생한다. 따라서 냉난방 부하가 승용 전기차에 비해 더 크게 요구된다. 결과적으로 승객이 요구하는 열 쾌적성을 만족하기 위해서 냉난방 시스템이 소비하는 에너지가 승용 전기차 보다 크다. 이러한 단점을 극복하기 위해 효율적인 통합공조 시스템을 적용한 연구를 수행했다. 최종적으로 1톤급의 경상용 전기트럭의 상품성 개선과 전기트럭 분야의 산업 생태계 기반 확충을 위한 고효율 공조 시스템 개발을 위해 냉방을 위한 전동식 압축기와 난방을 위한 히트펌프 시스템의 구상 설계와 해석적 검증을 수행한다.

• 동력기계공학회지
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• 제2권3호
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• pp.27-33
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• 1998

The room temperature and air conditioning load in the underground space have been investigated numerically by the unsteady heat conduction equation. The model room has 3 m in height and 10 m in width, and it's position in the underground depth are 0.5 m to 5 m. When the room was located around surface, the room temperatures were strongly influenced by the atmosphere. But the underground depth is more than 2 m, the yearly temperature amplitude was small and the temperature phase was delayed. Up to 5 m of the depth, the cooling and heating load was decreased rapidly, but over 10 m of the depth, the air conditioning load was constant.

• 한국태양에너지학회 논문집
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• 제23권2호
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• pp.51-58
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• 2003

PSHC(Prismatic Solar Hybrid Collector) is a passive solar system composed of prismatic acrly glazing, glazing and ventilating fan. This PSHC system is applied to effectively reduce heating ventilation load as well as lighting load. But so far no method appraising thermal performance of this PSHC system has been developed yet. To assess thermal performance of the PSHC system, a prototype PSHC experimental facility and TRNSYS subroutine type-205 model have been developed in Korea Institute of Energy Research (KIER). The results indicated that l)TRNSYS empirical model of PSHC has been properly modeled with actual performance data, 2)a more reliable source of weather data such as NASA and KIER weather station have been also obtained, and therefore, 3)the annual energy performance of PSHC could be assessed based on this proposed TRNSYS model.

• 한국태양에너지학회 논문집
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• 제30권5호
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• pp.69-76
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• 2010

In this study, the solar thermal and geo-source heat pump(GSHP) hybrid system for heating and cooling of Zero Energy Solar House(ZESH) was analyzed by experiment. The GSHP in this hybrid system works like as aback-up device for solar thermal system. This hybrid system was designed and installed for Zero Energy Solar House (KIER ZeSH) in Korea Institute of Energy Research. The purpose of this study is to find out that this system is optimized and operated normally for the heating load of ZeSH. The analysis was conducted as followings ; - the thermal performance of facade integrated solar collector - the on/off characteristics of solar system and GSHP - the contribution of solar thermal system. - the performance of solar thermal and ground source heat pump system respectively. - the meet of thermal load (space and water heating load). This experimental study could be useful for the optimization of this system as well as its application in house. This hybrid system could be commercialized for the green home if it is developed to a package type.

• 에너지공학
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• 제15권3호
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• pp.194-201
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• 2006

온실은 작물의 성장조건을 맞추기 위해서 야간 및 추운 날에는 난방을 해야 한다. 지열원 히트펌프 시스템은 냉난방 시스템에서 두드러진 관심을 보이고 있다. 축열조를 채용한 수평형 지열원 히트펌프 시스템을 온실에 적용하여 성능특성을 조사하였다. 그리고 축열조를 채용한 이유를 자세하게 설명하였다. 축열조는 지열원 히트펌프 시스템의 난방능력보다 큰 난방부하를 대응할 수 있다. 연구 결과, 시스템전체의 성능계수는 2.69로 나타났다.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2007년도 추계학술대회 논문집
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• pp.505-510
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• 2007

Greenhouses should be heated during nights and co Id days in order to fit growth conditions in greenhouses. Ground source heat pump(GSHP) or geothermal heat pump system(GHPs) is recognized to be outstanding heating and cooling system. Horizontal GSHP system is typically less expensive than vertical GSHP system but requires wide ground area to bury ground heat exchanger (GHE). In this study, a horizontal GSHP system with thermal storage tank was installed in greenhouse and investigated as performance characteristics. In the daytime, heating load of greenhouse is very small or needless because solar radiation increases inner air temperature. The results of study showed that the heating coefficient of performance of the heat pump($COP_h$) was 2.9 and the overall heating coefficient of performance of the system($COP_{sys}$) was 2.4. Heating energy cost was saved 76% using the horizontal GSHP system with thermal storage tank.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2007년도 동계학술발표대회 논문집
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• pp.447-452
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• 2007

Greenhouses should be heated during nights and cold days in order to fit growth conditions in greenhouses. Ground source heat pump(GSHP) or geothermal heat pump system(GHPs) is recognized to be outstanding heating and cooling system. Horizontal GSHP system is typically less expensive than vertical GSHP system but requires wide ground area to bury ground heat exchanger(GHE). In this study, a horizontal GSHP system with thermal storage tank was installed in greenhouse and investigated as performance characteristics. In the daytime, heating load of greenhouse is very small or needless because solar radiation increases inner air temperature. The results of study showed that the heating coefficient of performance of the heat pump ($COP_h$) was 2.9 and the overall heating coefficient of performance of the system($COP_{sys}$) was 2.4. Heating energy cost was saved 76% using the horizontal GSHP system with thermal storage tank.