DOI QR코드

DOI QR Code

Development of a Groundwater Source Heat Pump in a Fractured Rock Aquifer

암반 대수층에서 개방형 지열 시스템의 개발 및 적용

  • Shim, Byoung Ohan (Groundwater Research Center, Korea Institute of Geoscience and Mineral Resources) ;
  • Kim, Seong-Kyun (Groundwater Research Center, Korea Institute of Geoscience and Mineral Resources) ;
  • Choi, Hanna (Groundwater Research Center, Korea Institute of Geoscience and Mineral Resources) ;
  • Lee, Soo-Hyoung (Groundwater Research Center, Korea Institute of Geoscience and Mineral Resources) ;
  • Ha, Kyoochul (Groundwater Research Center, Korea Institute of Geoscience and Mineral Resources) ;
  • Kim, Yongchul (Groundwater Research Center, Korea Institute of Geoscience and Mineral Resources)
  • Received : 2021.06.10
  • Accepted : 2021.07.06
  • Published : 2021.09.25

Abstract

A groundwater source heat pump (GWHP) was developed in this study by adapting a borehole heat exchanger with closed-loop and open-loop systems in a new building. In the pilot test building, the air-conditioning on the second floor was designed to employ a closed-loop system and that on the third floor had an open-loop system. The GWHP design is based on the feasibility of groundwater resources at the installation site. For the hydrogeological survey of the study site, pumping and injection tests were conducted, and the feasibility of GWHP installation was evaluated based on the air-conditioning load demand of the building. The site was found to be satisfactory for the design capacity of the thermal load and water quality. In addition, the effect of groundwater movement on the performance of the closed-loop system was tested under three different operational scenarios of groundwater pumping. The performance of the system was sustainable with groundwater flow but declined without appropriate groundwater flow. From long-term observations of the operation, the aquifer temperature change was less than 2℃ at the observation well and 5℃ at the injection well with respect to the initial groundwater temperature. This pilot study is expected to be of guidance for developing GWHPs at fractured rock aquifers.

Keywords

Acknowledgement

본 연구는 2021년도 한국지질자원연구원 주요사업(21-3411)의 일환으로 수행되었습니다.

References

  1. Ministry of Trade, Industry and Energy, 2020, "Act on promotion of development, use, and distribution of new energy and renewable energy", http://www.law.go.kr/DRF/lawService.do?OC=bogus024&ID=000299&target=law&type=HTML.
  2. Lee, J.Y., 2009, "Current status of ground source heat pumps in Korea", Renew. Sustain. Energy Rev., 13(6-7), 1560-1568. https://doi.org/10.1016/j.rser.2008.10.005
  3. Chiasson, A.D., 2016, "Geothermal heat pump and heat engine systems: Theory and practice", John Wiley & Sons.
  4. Lee, C.H., Kim, D.G., Yu, B.S., and Kim, B.I., 2020, "Study on the performance evaluation of smart heating and cooling heat pump system in a balancing well cross-conditioned ground heat exchanger", New. Renew. Energy, 16(4), 41-48.
  5. Ministry of environment, 2020, "Groundwater annual report", 11-1480000-001551-10.
  6. Rees, S. (Ed.), 2016, "Advances in ground-source heat pump systems", Woodhead Publishing.
  7. Bae, S., Kim, H., Kim, H., and Nam, Y., 2017, "Hydraulic feasibility study on the open-loop geothermal system using a pairing technology", J. Korea Inst. Ecol. Archit. And Environ., 17(5), 119-124.
  8. Park, Y., Mok, J.K., Jang, B.J., Park, Y.C., and Lee, J.Y., 2013, "Influence of open and closed loop geothermal cooling and heating Ssstems on hydrogeological properties", J. Geol. Soc., 49(6), 649-659.
  9. Shim, B.O., and Park, C.H., 2013, "Ground thermal conductivity for (ground source heat pumps) GSHPs in Korea", Energy, 56, 167-174. https://doi.org/10.1016/j.energy.2013.04.059
  10. Shim, B.O., Lee, Y., Kim, H.C., and Song, Y., 2006, "Investigation of thermal and hydraulic characteristics for the performance analysis of a borehole heat exchanger", J. Korean Soc. Miner. Energy Resour., 43(2), 97-105.
  11. VDI, V., 2010, "VDI 4640 thermal use of theu Underground. part 1: Fundamentals, approvals, environmental aspect", Berlin: VDI-Gessellschaft Energie und Umwelt (GEU).
  12. Choi, H., Kim, J., Shim, B.O., and Kim, D.H., 2020, "Characterization of aquifer hydrochemistry from the operation of a shallow geothermal system", Water, 12(5), 1377. https://doi.org/10.3390/w12051377
  13. Sophocleous, M., 2000, "From safe yield to sustainable development of water resources-the Kansas experience", J. Hydrol., 235(1-2), 27-43. https://doi.org/10.1016/S0022-1694(00)00263-8
  14. Kawecki, M., 1995, "Meaningful interpretation of step-drawdown tests", Groundwater, 33(1), 23-32. https://doi.org/10.1111/j.1745-6584.1995.tb00259.x
  15. Jacob, C.E., 1947, "Drawdown test to determine effective radius of artesian well", Trans. Am. Soc. Civil Eng., 112(1), 1047-1064. https://doi.org/10.1061/TACEAT.0006033
  16. Singh, S.K., 2002, "Well loss estimation: Variable pumping replacing step drawdown test", J. Hydraul. Eng., 128(3), 343-348. https://doi.org/10.1061/(asce)0733-9429(2002)128:3(343)
  17. Freeze, R.A. and Cherry, J.A., 1979, "Groundwater", Prentice-hall, Inc., Englewood Cliffs, Vol. 7632, 604.
  18. Duffield, G.M., 2007, "AQTESOLV for Windows Version 4.5 User's Guide", HydroSOLVE. Inc., Reston, VA.
  19. Bouwer, H., 2002, "Artificial recharge of groundwater: hydrogeology and engineering", Hydrogeol. J., 10(1), 121-142. https://doi.org/10.1007/s10040-001-0182-4
  20. Halford, K.J., Weight, W.D., and Schreiber, R.P., 2006, "Interpretation of transmissivity estimates from single-well pumping aquifer tests", Groundwater, 44(3), 467-471. https://doi.org/10.1111/j.1745-6584.2005.00151.x
  21. Jeon, S.K., Koo, M.H., Kim, Y., and Kang, I.O., 2005, "Statistical analysis of aquifer characteristics using pumping test data of national groundwater monitoring wells for Korea", J. of KoSSGE, 10(6), 32-44.