Performance and Feasibility Study of a Standing Column Well (SCW) System Using a Deep Geothermal Well

Abstract

Abstract:Deep geothermal heat pump systems have considerable energy saving potential for heating and cooling systems that use stable ground temperature and groundwater as their heat sources. However, deep geothermal systems have several limitations for real applications such as a very high installation cost and a lack of recognition as heating and cooling systems. In this study, we performed a feasibility assessment of a Standing Column Well (SCW) system using a deep geothermal well, based on a real-scale experiment in Korea. The results showed that the temperature of the heat source increased up to 42.04˝C in the borehole after the heating experiment, which is about 30˝C higher than that of normal shallow geothermal wells. Furthermore, the coefficient of performance (COP) of the heat pump during 3 months of operation was 5.8, but the system COP was only 3.6 due to the relatively high electric consumption of the pump. Moreover, the payback period of the system using a deep well for controlled horticulture in a glass greenhouse was calculated as 6 years compared with using a diesel boiler system.

Control strategy evaluation framework for ground source heat pumps using standing column wells

“…In the literature both experimental (Beaudry et al, 2019;Cho et al, 2016;Lee et al, 2019;Lim and Lee, 2021;Minea, 2013;Nguyen et al, 2020;Orio et al, 2005;Pasquier et al, 2016) and simulation studies (Beaudry et al, 2022(Beaudry et al, , 2021Nguyen et al, 2013) addressed the performance of GSHP systems using SCWs, some of which also explored different groundwater bleeding strategies (Beaudry et al, 2022;Nguyen et al, 2020Nguyen et al, , 2013.…”

Environmental Impact Comparison of Geothermal Alternatives for Conventional Boiler Replacement

“…Within this sector, there are different catchment systems for a geothermal facility. The two systems most used today are horizontal catchment systems [27,28] and vertical catchment systems [29]. However, there are also other types of systems to obtain the necessary geothermal energy source, such as surface systems.…”

Concepts and characteristics of a U-shaped docking well geothermal heat extraction system

“…Sun et al (2018) proposed a U-shaped closed loop geothermal system, but they didn't consider the impact of the length of the horizontal section. For the middle-deep geothermal resources or dry hot rock geothermal resources, most of the previous studies have focused on two aspects: (1) using concentric casing heat extraction system (Bae et al, 2018;Cho et al, 2016;Jin et al, 2012), but both the flow rate and the heat exchange efficiency were low; (2) drilling multiple deep wells for production and injection of working fluid, using fracturing, acidification and other measures to connect the heat reservoir (Cui et al, 2018;Yanagisawa et al, 2008;Zeng et al, 2013). But the process is complicated, the formation is connected to the geothermal system, the water recovery rate is low, and unfavorable recharge will cause land subsidence.…”