# 2000m 단일 시추공에서 밀폐 동축 방식 지중 열교환기의 취득온도 성능평가

• Accepted : 2016.07.04
• Published : 2016.08.31
• 21 10

#### Abstract

The Korean government has been making efforts to use renewable energy to reduce the consumption of fossil fuels for the heating system in greenhouses. The number of greenhouses that installed a geothermal heat pump system is 201 EA with the volume of 132.8 ha and 108,467kW from 2010-2014. The geothermal system, called a shallow geothermal system, with the temperature of $10-20^{\circ}C$ has accessories composed of a BHE and heat pump. Moreover, it is necessary to have a wide area to install the BHE and to drill to the depth of 200 m. On the other hand, even though the deep geothermal system needs a high drilling cost to obtain the temperature of $40-150^{\circ}C$, the system has the advantages of the small area required for the BHE and operation without a heat pump. In this study, the temperature of the return water and heat capacity were measured to obtain the geothermal energy efficiently on the condition of the water flow being changed in the BHE. The temperature according to the return water changes through the heat conduction based on the increase of ground temperature up to the underground depth has been calculated to conduct a simulation and is compared with the field experiment test results.

#### Keywords

Deep Geothermal;Heat Exchanger;Heat Gain;Flow Velocity;Green House

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#### Acknowledgement

Supported by : 농림수산식품기술기획평가원(iPET)