Controlling injection conditions of a deep coaxial closed well heat exchanger to meet irregular heat demands: a field case study in Belgium (Mol)

Abstract Deep geothermal closed-loops have recently gained attention because of their advantages over classical geothermal applications (e.g., less dependence on the geology, no risk of induced seismicity) and technological advantages (e.g., in the drilling process, use of alternative to water fluid...

Full description

Saved in:
Bibliographic Details
Main Authors: Vlasios Leontidis, Edgar Hernandez, Justin Pogacnik, Magnus Wangen, Virginie Harcouët-Menou
Format: Article
Language:English
Published: SpringerOpen 2025-01-01
Series:Geothermal Energy
Subjects:
Online Access:https://doi.org/10.1186/s40517-025-00331-y
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1832571894574874624
author Vlasios Leontidis
Edgar Hernandez
Justin Pogacnik
Magnus Wangen
Virginie Harcouët-Menou
author_facet Vlasios Leontidis
Edgar Hernandez
Justin Pogacnik
Magnus Wangen
Virginie Harcouët-Menou
author_sort Vlasios Leontidis
collection DOAJ
description Abstract Deep geothermal closed-loops have recently gained attention because of their advantages over classical geothermal applications (e.g., less dependence on the geology, no risk of induced seismicity) and technological advantages (e.g., in the drilling process, use of alternative to water fluids). This paper deals with the repurposing of an existing well in Mol, Belgium, by numerically evaluating the closed-loop concept. Two numerical tools are used to predict the evolution of the temperature and the produced energy over a period of 20 years considering the vertical coaxial well and the complete geological morphology. Full-scale simulations are initially carried out to estimate the maximum capacity of the well and to highlight the need to control the output of the well by adjusting the inlet conditions. Simulations are then performed either to deliver a constant power or to cover irregular thermal energy demands of two buildings by applying in both cases three process control operations. Through controlling the inlet temperature, the injected flow rate or successively both, the production of excess energy, resulting from the overdesign of the existing wellbore for the specific application, is limited. The simulations showed that continuous adjustments to the injection temperature and/or flow rate are needed to restrict the rapid drop in outlet temperature and consequent thermal depletion of the rocks, caused by the highly transient nature of the diffusive heat transfer from the rocks to the wellbore, as well as to supply a specific heat demand, constant or irregular, over the long term. In fact, the combination of both controls could be the ideal strategy for supplying the demand at the highest COP.
format Article
id doaj-art-e2add484f89148a487e7ee808cfa68a6
institution Kabale University
issn 2195-9706
language English
publishDate 2025-01-01
publisher SpringerOpen
record_format Article
series Geothermal Energy
spelling doaj-art-e2add484f89148a487e7ee808cfa68a62025-02-02T12:15:35ZengSpringerOpenGeothermal Energy2195-97062025-01-0113113410.1186/s40517-025-00331-yControlling injection conditions of a deep coaxial closed well heat exchanger to meet irregular heat demands: a field case study in Belgium (Mol)Vlasios Leontidis0Edgar Hernandez1Justin Pogacnik2Magnus Wangen3Virginie Harcouët-Menou4IFP Energies NouvellesFlemish Institute of Technological Research (VITO)Flemish Institute of Technological Research (VITO)Institute for Energy TechnologyFlemish Institute of Technological Research (VITO)Abstract Deep geothermal closed-loops have recently gained attention because of their advantages over classical geothermal applications (e.g., less dependence on the geology, no risk of induced seismicity) and technological advantages (e.g., in the drilling process, use of alternative to water fluids). This paper deals with the repurposing of an existing well in Mol, Belgium, by numerically evaluating the closed-loop concept. Two numerical tools are used to predict the evolution of the temperature and the produced energy over a period of 20 years considering the vertical coaxial well and the complete geological morphology. Full-scale simulations are initially carried out to estimate the maximum capacity of the well and to highlight the need to control the output of the well by adjusting the inlet conditions. Simulations are then performed either to deliver a constant power or to cover irregular thermal energy demands of two buildings by applying in both cases three process control operations. Through controlling the inlet temperature, the injected flow rate or successively both, the production of excess energy, resulting from the overdesign of the existing wellbore for the specific application, is limited. The simulations showed that continuous adjustments to the injection temperature and/or flow rate are needed to restrict the rapid drop in outlet temperature and consequent thermal depletion of the rocks, caused by the highly transient nature of the diffusive heat transfer from the rocks to the wellbore, as well as to supply a specific heat demand, constant or irregular, over the long term. In fact, the combination of both controls could be the ideal strategy for supplying the demand at the highest COP.https://doi.org/10.1186/s40517-025-00331-yDeep borehole heat exchangerClosed-loop geothermal systemHOCLOOPNumerical modellingHeterogeneous formationIrregular heat demand
spellingShingle Vlasios Leontidis
Edgar Hernandez
Justin Pogacnik
Magnus Wangen
Virginie Harcouët-Menou
Controlling injection conditions of a deep coaxial closed well heat exchanger to meet irregular heat demands: a field case study in Belgium (Mol)
Geothermal Energy
Deep borehole heat exchanger
Closed-loop geothermal system
HOCLOOP
Numerical modelling
Heterogeneous formation
Irregular heat demand
title Controlling injection conditions of a deep coaxial closed well heat exchanger to meet irregular heat demands: a field case study in Belgium (Mol)
title_full Controlling injection conditions of a deep coaxial closed well heat exchanger to meet irregular heat demands: a field case study in Belgium (Mol)
title_fullStr Controlling injection conditions of a deep coaxial closed well heat exchanger to meet irregular heat demands: a field case study in Belgium (Mol)
title_full_unstemmed Controlling injection conditions of a deep coaxial closed well heat exchanger to meet irregular heat demands: a field case study in Belgium (Mol)
title_short Controlling injection conditions of a deep coaxial closed well heat exchanger to meet irregular heat demands: a field case study in Belgium (Mol)
title_sort controlling injection conditions of a deep coaxial closed well heat exchanger to meet irregular heat demands a field case study in belgium mol
topic Deep borehole heat exchanger
Closed-loop geothermal system
HOCLOOP
Numerical modelling
Heterogeneous formation
Irregular heat demand
url https://doi.org/10.1186/s40517-025-00331-y
work_keys_str_mv AT vlasiosleontidis controllinginjectionconditionsofadeepcoaxialclosedwellheatexchangertomeetirregularheatdemandsafieldcasestudyinbelgiummol
AT edgarhernandez controllinginjectionconditionsofadeepcoaxialclosedwellheatexchangertomeetirregularheatdemandsafieldcasestudyinbelgiummol
AT justinpogacnik controllinginjectionconditionsofadeepcoaxialclosedwellheatexchangertomeetirregularheatdemandsafieldcasestudyinbelgiummol
AT magnuswangen controllinginjectionconditionsofadeepcoaxialclosedwellheatexchangertomeetirregularheatdemandsafieldcasestudyinbelgiummol
AT virginieharcouetmenou controllinginjectionconditionsofadeepcoaxialclosedwellheatexchangertomeetirregularheatdemandsafieldcasestudyinbelgiummol