• Title/Summary/Keyword: Ground Source Heat

Search Result 304, Processing Time 0.023 seconds

A Study on Comparative Analysis of Energy Performance of Hybrid Heat Pump Systems Using Ground Heat Source and Water Heat Source (지열원과 수열원을 이용한 하이브리드 히트펌프 시스템의 에너지 성능 비교 분석 연구)

  • Park, Sihun;Kim, Jonghyun;Min, Joonki
    • Journal of the Korean Society for Geothermal and Hydrothermal Energy
    • /
    • v.17 no.4
    • /
    • pp.59-67
    • /
    • 2021
  • In this study, the performance of the single heat source system and the hybrid system was comparatively analyzed. Case 1 is a ground heat source system, and Case 2 is a water heat source system. Case 3, a hybrid system, reduced the capacity of the ground heat source and applied a water heat source as an auxiliary heat source, and Case 4 was composed of a system that applied a water heat source as an auxiliary heat source to the ground heat source system. As a result of the simulation, in case 3, energy consumption was reduced by up to 2.67% compared to ground sources for cooling. In Case 4, COP was improved by up to 10.02% compared to ground sources during cooling, and EST was calculated to be 2.42℃ lower. During heating, 0.83% was improved compared to the water heat source. At this time, the EST was calculated to be 2.25℃ higher than the water heat source.

A Study on the Monitoring Methods for Energy Production in Ground Source Heat Pump System (지열원 열펌프 시스템의 에너지 생산량 모니터링 신뢰도 향상 방안 연구)

  • Kang, Shin-Hyung;Lee, Kwang Ho;Do, Sung Lok;Choi, Jong Min
    • Journal of the Korean Society for Geothermal and Hydrothermal Energy
    • /
    • v.15 no.2
    • /
    • pp.10-16
    • /
    • 2019
  • In this study, the present regulation of heat metering for the ground source heat pump was investigated. The ground source heat pump has been adopting the heat metering system used in the district heating system for estimating the heating and cooling energy production amount. The accuracy of the present heat metering systems for a water to water ground source heat pump is low, because the system for district heating has a relatively high temperature range comparing with the ground source heat pump operating conditions. Even though the heat amount for the building side should be measured, the heat absorption and extraction amount from or to the ground was measured for the water to air ground source heat pump due to the difficulty of estimating the air side heating and cooling capacity in the present regulation. It is highly recommended to validate the heat metering system to have reliability for the ground source heat pump and develop the system to be applicable water to air ground source heat pump.

Study on Energy Consumption of Air-source, Ground-source and Dual-source Heat Pump during Intermediate Season (공기, 지열 및 복합 열원 열펌프의 중간기 에너지 소비량에 관한 연구)

  • Cho, Yeong Uk;Woo, Tea Ho;Chung, Kwang-Seop;Kim, Youngil
    • Journal of the Korean Society for Geothermal and Hydrothermal Energy
    • /
    • v.9 no.4
    • /
    • pp.1-7
    • /
    • 2013
  • This study is to compare energy consumption of air-source, ground-source and dual-source heat pump systems during intermediate season using dynamic simulation. Ground-source heat pump has higher COP than that of air-source but requires additional power consumption of auxiliary equipment such as circulation pump. During intermediate season when the outdoor air temperature is favorable, total COP of air-source heat pump may be greater than that of ground-source when circulation pump power consumption is included. Dual-source heat pump which selects the more favorable heat source is compared with air-source only and ground-source only heat pumps for total power consumption. Results show that power consumption of dual-source heat pump is lower than that of ground-source only by 0.73%.

Cooling Performance of Ground source Heat Pump using Effluent Ground Water (유출지하수 열원 지열히트펌프시스템의 냉방성능)

  • Park, Geun-Woo;Nam, Hyun-Ku;Kang, Byung-Chan
    • New & Renewable Energy
    • /
    • v.3 no.4
    • /
    • pp.47-53
    • /
    • 2007
  • Effluent ground water overflow in deep and broad ground space building. Temperature of effluent ground water is in $12{\sim}20^{\circ}C$ annually and the quality of that water is as good as living water. Therefore if the flow rate of effluent ground water is sufficient as source of heat pump, that is good heat source and heat sink of heat pump. Effluent ground water contain the thermal energy of surrounding ground. So this is a new application of ground source heat pump. In this study open type and close type heat pump system using effluent ground water was installed and tested for a church building with large and deep ground space. The effluent flow rate of this building is $800{\sim}1000ton/day$. The heat pump capacity is 5RT each. The heat pump cooling COP is $4.9{\sim}5.2$ for the open type and $4.9{\sim}5.7$ for close type system. The system cooling COP is $3.2{\sim}4.5$ for open type and $3.8{\sim}4.2$ for close type system. This performance is up to that of BHE type ground source heat pump.

  • PDF

Cooling Performance of Ground source Heat Pump using Effluent Ground Water (유출지하수 열원 지열히트펌프시스템의 냉방성능)

  • Park, Geun-Woo;Nam, Hyun-Ku;Kang, Byung-Chan
    • 한국신재생에너지학회:학술대회논문집
    • /
    • 2007.11a
    • /
    • pp.471-476
    • /
    • 2007
  • Effluent ground water overflow in deep and broad ground space building. Temperature of effluent ground water is in $12{\sim}20^{\circ}C$ annually and the quality of that water is as good as living water. Therefore if the flow rate of effluent ground water is sufficient as source of heat pump, that is good heat source and heat sink of heat pump. Effuent ground water contain the thermal energy of surrounding ground. So this is a new application of ground source heat pump. In this study open type and c lose type heat pump system using effluent ground water was installed and tested for it church building with large and deep ground space. The effluent flow rate of this building is $800{\sim}1000$ ton/day. The heat pump capacity is 5RT each. The heat pump cooling COP is $4.9{\sim}5.2$ for the open type and $4.9{\sim}5.7$ for close type system. The system cooling COP is $3.2{\sim}4.5$ for open type and $3.8{\sim}4.2$for close type system. This performance is up to that of BHE type ground source heat pump.

  • PDF

Heating Performance of Ground source Heat Pump using Effluent Ground Water (유출지하수 열원 지열히트펌프시스템의 난방성능)

  • Park, Geun-Woo;Lee, Eung-Youl
    • New & Renewable Energy
    • /
    • v.3 no.2 s.10
    • /
    • pp.40-46
    • /
    • 2007
  • Effluent ground water overflow in deep and broad ground space building. Temperature of effluent ground water is in $12{\sim}20^{\circ}...$ annually and the quality of that water is as good as well water. Therefore if the flow rate of effluent ground water is sufficient as source of heat pump, that is good heat source and heat sink of heat pump. Effuent ground water contain the thermal energy of surrounding ground. So this is a new application of ground source heat pump. In this study open type and close type heat pump system using effluent ground water was installed and tested for a church building with large and deep ground space. The effluent flow rate of this building is $800{\sim}1000\;ton/day$. The heat pump capacity is 5RT. The heat pump heating COP was $3.85{\sim}4.68$ for the open type and $3.82{\sim}4.69$ for the close type system. The system heating COP including pump power is $3.0{\sim}3.32$ for the open type and $3.32{\sim}3.84$ for close type system. This performance is up to that of BHE type ground source heat pump.

  • PDF

A study on the Heat Transfer Performance according to Ground Heat Exchanger Types (지중열교환기의 종류에 따른 열전달 성능에 관한 연구)

  • Hwang, SuckHo;Song, Doosam
    • KIEAE Journal
    • /
    • v.10 no.4
    • /
    • pp.75-80
    • /
    • 2010
  • Generally, ground-source heat pump (GSHP) systems have a higher performance than conventional air-source systems. However, the major fault of GSHP systems is their expensive boring costs. Therefore, it is important issue that to reduce initial cost and ensure stability of system through accurate prediction of the heat extraction and injection rates of the ground heat exchanger. Conventional analysis methods employed by line source theory are used to predict heat transfer rate between ground heat exchanger and soil. Shape of ground heat exchanger was simplified by equivalent diameter model, but these methods do not accurately reflect the heat transfer characteristics according to the heat exchanger geometry. In this study, a numerical model that combines a user subroutine module that calculates circulation water conditions in the ground heat exchanger and FEFLOW program which can simulate heat/moisture transfer in the soil, is developed. Heat transfer performance was evaluated for 3 different types ground heat exchanger(U-tube, Double U-tube, Coaxial).

Study on COP Variations with the duration of Ground Source Heat Pump Systems Operation (지열히트펌프의 작동시간 경과에 따른 COP 변화에 대한 연구)

  • Lee, Yonggyu;Baek, Namchoon;Yoon, Eungsang
    • 한국신재생에너지학회:학술대회논문집
    • /
    • 2010.06a
    • /
    • pp.198.2-198.2
    • /
    • 2010
  • In this study, the COP variation with the duration of Ground Source Heat Pump (GSHP) systems operation was analyzed by experiment. This experimental facility was installed in residential house as a back-up device of solar thermal heating system. The capacity of heat pump is 2.5 kW with a vertical bore hole of 150m depth. The COP of GSHP is varied, depending on the ground temperature which is used as a heat source. The ground heat source temperature influencing heating COP is the soil or rock temperature which adjoin with geo-source heat exchanger. This temperature is decreased rapidly according to the operation duration of heat pump. As a result, COP of GSHP is decreased to 3 in one hour of continuous operation time.

  • PDF

A Study on the Performance Evaluation of Combined Heat Pump System according to the Ratio of Ground Heat Source and Water Heat Source (지열원 및 수열원 비율에 따른 복합열원 히트펌프시스템 성능 평가 연구)

  • Park, Sihun;Ko, Yujin;Min, Joonki
    • Journal of the Korean Society for Geothermal and Hydrothermal Energy
    • /
    • v.17 no.2
    • /
    • pp.11-19
    • /
    • 2021
  • In this study, combined heat source heat pump system was implemented with 4 single heat source heat pumps each applied with a geothermal source and a water source. Five cases (Case1~Case5) were configured to conduct a performance comparison and analysis of the combined heat source heat pump system. First of all, as a result of analyzing the heat source, the case when 4 ground heat sources were applied (Case1) showed a uniform EST(Entering Source Temperature) distribution throughout the year since it is less affected by outside air compared to the case when 4 water heat sources were applied (Case5). In both winter and summer, the ground heat source maintained higher EST than the water heat source. Therefore, the system with high ratio of geothermal sources is advantageous for heating, and with high ratio of water heat sources is advantageous for cooling.

A Study on Heating Characteristics of Ground Source Heat Pump with Variation of Heat Exchange Methods (열교환방식에 따른 지열히트펌프의 난방특성에 관한 연구)

  • Cha, Dong-An;Kwon, Oh-Kyung;Park, Cha-Sik
    • Journal of the Korean Society for Geothermal and Hydrothermal Energy
    • /
    • v.8 no.2
    • /
    • pp.9-15
    • /
    • 2012
  • The objective of this study is to investigate the influence on the heating performance for a water-to-water 10RT ground source heat pump by using the water switching and refrigerant switching method. The test of water-to-water ground source heat pump was measured by varying the compressor speed, load side inlet temperature, and ground heat source side temperature. The heating capacity and COP of the heat pump increased with increasing ground heat source temperature. As a result, compared to a refrigerant switching method, the water switching method with counter flow improves the heating capacity and COP by approximately 5% in average, respectively.