• Title/Summary/Keyword: Geothermal Energy

Search Result 913, Processing Time 0.025 seconds

Daily Cooling Performance Comparison of a Geothermal Heat Pump System between Energy-Pile and Energy-Slab (에너지파일과 에너지슬래브 적용 지열원 열펌프 시스템의 일일 냉방 운전 특성 비교)

  • Choi, Jong-Min;Park, Yong-Jung;Kang, Shin-Hyung
    • Journal of the Korean Society for Geothermal and Hydrothermal Energy
    • /
    • v.8 no.3
    • /
    • pp.29-35
    • /
    • 2012
  • Geothermal heat pump system has been spotlighted as an efficient building energy system, because it has great potentials for reducing energy in building air conditioning and reducing $CO_2$ emissions. However, higher initial cost is a barrier to the promotion of its use. Energy-pile and energy-slab are known as low cost ground heat exchangers comparing with conventional ground heat exchangers, because they utilize building structures as ground heat exchangers. This paper presents the daily cooling performance of a geothermal heat pump system with energy-pile and energy-slab. The energy-piles and the energy-slabs are connected to heat pump units in parallel. The cooling capacity of the system was nearly constant due to the stability of the ground heat exchangers. The stability of the energy-pile was a little higher than that of the energy-stab as a heat sink.

Annual Performance Evaluation of Direct Expansion Vertical Closed-Loop Ground Source Heat Pump for Residential Application (주거용 직접순환식 수직밀폐형 지열원 열펌프의 연간 운전성능 평가)

  • Kim, Min-Sung;Baik, Young-Jin;Ra, Ho-Sang
    • Journal of the Korean Solar Energy Society
    • /
    • v.32 no.3
    • /
    • pp.114-122
    • /
    • 2012
  • Vertical closed-loop ground source heat pump systems(GSHP) have been installed widely in Korea since it can extract moderate temperature level of geothermal heat in a small area. As a ground heat exchanger, a vertical closed -loop type with brine circulation is mostly preferred since it is simple and less harmful to ground environment. However, it requires a secondary heat exchange loop between the refrigerant in a heat pump and the brine. By adding a geothermal heat exchanger in the secondary heat exchange loop, circulation pumps should be attached and the temperature difference between refrigerant and ground is increased, which are important parts of performance degradation. In this paper, annual and seasonal performances of direct expansion(DX) geothermal heat pump were estimated mathematically as an alternative of classical indirect geothermal heat pump based on the annual performance evaluation. As results, DX geothermal heat pump showed 43% higher annual performance than the classical U-tube geothermal heat pump.

Application for Heating and Cooling System Using Sewage Water (100RT급 하수열원 냉난방시스템 적용)

  • Chang, Ki-Chang;Yoon, Hyung-Kee;Park, Seong-Ryong;Baik, Young-Jin;Ra, Ho-Sang;Shin, Kwang-Ho
    • Proceedings of the SAREK Conference
    • /
    • 2006.06a
    • /
    • pp.215-220
    • /
    • 2006
  • Along with socioeconomic development and improving standard of living, the heat demand for heating and cooling in residential and commercial sectors is expected to expand rapidly, reaching over 43 million TOE by 2010 in Korea(about 80% increase compared with that in 1995). Since most of this heat demand is loop temperature below $60^{\circ}C$, the utilization of 'unused energy' is surely one of very effective measures to both environmental preservation and energy conservation. 'Unused energy' in this paper is implicated as 'temperature differential energy' available from treated sewage water, useful and abundant heat source for heat pump(cooler in summer and warmer in winter than outside air). An analysis was carried out to estimate the energy potential of treated sewage water for heat pump heat source. Some analysis were taken to study the characteristics of a heat pump system using the treated sewage water as heat source.

  • PDF

Evaluation of the Annual Performance of the Direct Expansion Vertical Closed-Loop Ground Source Heat Pump (직접순환식 수직밀폐형 지열원 열펌프의 연간 운전성능 평가)

  • Kim, Min-Sung;Woo, Joung-Son;Baik, Young-Jin;Jang, Jea-Chul;Kim, Ji-Young;Ra, Ho-Sang
    • 한국태양에너지학회:학술대회논문집
    • /
    • 2012.03a
    • /
    • pp.534-542
    • /
    • 2012
  • Vertical closed-loop ground source heat pump systems(GSHP) have been installed widely in Korea since it can extract moderate temperature level of geothermal heat in a small area. As a ground heat exchanger, a vertical closed-loop type with brine circulation is mostly preferred since it is simple and less harmful to ground environment. However, it requires a secondary heat exchange loop between the refrigerant in a heat pump and the brine. By adding a geothermal heat exchanger in the secondary heat exchange loop, circulation pumps should be attached and the temperature difference between refrigerant and ground is increased, which are important parts of performance degradation. In this paper, annual and seasonal performances of direct expansion(DX) geothermal heat pump were estimated mathematically as an alternative of classical indirect geothermal heat pump based on the annual performance evaluation. As a result, DX geothermal heat pump showed 43% higher annual performance than the classical U-tube geothermal heat pump.

  • PDF

A Study on the Geothermal Heat Pump System Performance Analysis according to Water Flow Rate Control of the Geothermal Water Circulation Pump (지열순환펌프 유량변화에 따른 지열히트펌프시스템의 에너지 성능 평가)

  • Jung, Young-Ju;Jo, Jae-Hun;Kim, Yong-Shik;Cho, Young-Hum
    • Journal of the Korean Solar Energy Society
    • /
    • v.34 no.6
    • /
    • pp.103-109
    • /
    • 2014
  • It is important to control the amount of supply water flow rate at all kinds of HVAC systems in order to maintain IAQ and energy efficiency. The most of buildings installed geothermal heat pumps is using fixed water flow rate in spite of the excellent performance of geothermal heat pumps. Especially when the air-conditioning load is low, the flow rate control may be possible to save energy to operate. However, it is effective to apply the variable flow control system in order to reduce energy consumption. Therefore, the purpose of this study, change a water flow rate and improve the whole performance of the geothermal heat pump. Geothermal heat pump system is modeled after the selection of the applied building, by setting the flow rate control to be analyzed through a simulation of performance evaluation. Building energy saving according to the flow rate of the ground circulating water analyze quantitatively and to investigate the importance of the flow control.

ISO performance data based commissioning technique for GSHP system (ISO 성능데이터를 이용한 지열히트펌프 시스템의 성능 확인 커미셔닝 기술)

  • Ko, Gun-Hyuk;Kim, Ji-Young;Kang, Eun-Chul;Chang, Ki-Chang;Lee, Euy-Joon
    • Journal of the Korean Society for Geothermal and Hydrothermal Energy
    • /
    • v.4 no.2
    • /
    • pp.1-7
    • /
    • 2008
  • GSHP(Ground Source Heat Pump) has been extensively disseminated due to the recent increasing demand over new and renewable energy. However, the system reliability has been key issues and barriers to insure a better system performance as designed originally in ISO (international standard organization) standard. This paper introduces a systematic method to verify its intended design target so called as ISO performance data based commissioning technology for a water to air GSHP system. The commissioning technology starts from are to the international standard ISO performance data of a GSHP model and to compare its installed operation data and to calibrate and tune to the target optimum operation parameters. Results indicated that cooling capacity could be raised up to 76.6% from 46.6% from this proposed commissioning technology.

  • PDF

Analysis on the Performance Evaluation Trends of Heat Pumps and the Test Standards of a Geothermal Heat Pump in Korea (히트펌프 성능 평가 동향과 국내 지열원 히트펌프 성능 평가 규격 및 제도 분석)

  • Kang, Shin-Hyung;Choi, Jong Min
    • Journal of the Korean Society for Geothermal and Hydrothermal Energy
    • /
    • v.13 no.4
    • /
    • pp.31-38
    • /
    • 2017
  • The heating and cooling air conditioning field has been increasing the problems of energy consumption and global warming in the world. A geothermal heat pump has been known as one of the highest efficient heating and cooling system. In this study, the analysis about the test standards of the geothermal heat pump of the Republic of Korea was executed. From the research, the following results were given. It is needed to address the domestic test standard for direct heat exchange geothermal heat pump. Water to air multi geothermal heat pump test standard was only developed in Korea. The test standard to calculate a seasonal energy efficiency ratio for cooling period and heat seasonal performance factor for heating period should be newly developed to estimate actual annual energy consumption and $CO_2$ emission.

Application textile-type geothermal heat exchanger for tunnel (텍스타일형 지중열교환기의 터널에서의 적용)

  • Lee, Chul-Ho;Lee, Kang-Ja;Gil, Hu-Jeong;Jeoung, Jae-Hyeung;Choi, Hang-Seok
    • 한국신재생에너지학회:학술대회논문집
    • /
    • 2009.06a
    • /
    • pp.604-607
    • /
    • 2009
  • The geothermal energy have been developed as the pro-environmental and the substantial long-term energy. Recently energy foundations and other thermo-active ground structures have been developed to enhance the use of geothermal energy. In this research, a tunnel wall is focused as a source of geothermal energy. If the tunnel wall can be used for geothermal source, it can provide relatively lower cost because it is not necessary to make a deep borehole like in case of closed-loop vertical ground heat exchanger. For analyzing efficiency of heat exchanger in tunnel, laboratory tests and the numerical analyses are performed.

  • PDF