Japan Geoscience Union Meeting 2015

Presentation information

Print

Poster

Symbol A (Atmospheric and Hydrospheric Sciences) » A-HW Hydrology & Water Environment

[A-HW25] Groundwater and environmental geology in urban areas

Wed. May 27, 2015 6:15 PM - 7:30 PM Convention Hall (2F)

Convener:*Masaya Yasuhara(Geological Survey of Japan, AIST), Takeshi Hayashi(Faculty of Education and Human Studies, Akita University), Motoyuki Asada(Shimizu Corporation), Satoshi Takizawa(Department of Urban Engineering, Graduate School of Engineering, the University of Tokyo), Hiroaki SUZUKI(Strategic Technology Development Dept. Research & Development Center, Nippon Koei Co., Ltd.), Kei Nishida(Interdisciplinary Graduate School of Medicine and Engineering, the University of Yamanashi)

6:15 PM - 7:30 PM

[AHW25-P04] Long-term monitoring for groundwater temperature at closed loop GSHPs installed site

*Youngyun PARK1, Jong-koo MOK2, Bum-ju JANG2, Seung-jin LEE2, Yu-chul PARK3, Jin-yong LEE1 (1.Department of Geology, Kangwon National University, Republic of Korea, 2.Geo3eco Co. Ltd., Chuncheon, Republic of Korea, 3.Department of Geophysics, Kangwon National University, Republic of Korea)

Keywords:Open loop, Ground source heat pump, Groundwater temperature, Korea

This study was performed to evaluate the influence of closed loop ground source heat pumps (GSHPs) on groundwater temperature. The closed loop ground source heat pumps was installed in 2009 and their capacity is 6,952 kW. The monitoring well was installed between wells used to closed loop GSHP and was located approximately 3.5 m away from well used to closed loop GSHP. The groundwater temperature were hourly measured from May 2010 to June 2013. The air temperature had ranged from -15.7 to 30.4oC and showed significant seasonal variations. The water temperature at monitoring well ranged from 13.3 to 16.3oC and their fluctuation trend was similar to air temperature. However, background of groundwater temperature showed narrow range (12.8 to 14.7oC) compared with that at monitoring well. In addition, background of groundwater temperature showed relatively weak seasonal variations. The phase difference between air and groundwater temperature at monitoring well was from approximately 4 to 5 months. The slope of regression line for air and background groundwater temperature was -0.006 and -0.01 oC/day, respectively. In contrast, the slope of regression line for groundwater temperature at monitoring well was 0.05 oC/day. These results indicate that thermal energy is cumulated in groundwater owing to operation of closed loop GSHPs in the study area. These trends can keep going. Therefore, the influence of closed loop GSHPs on groundwater temperature has to be evaluated to conserve groundwater from thermal contamination by operation of closed loop GSHPs and to keep energy efficiency. This work is supported by the Korean Ministry of Environment under "The GAIA project (2014000530001)".