Abstract
Background: The thermal effect on the subsurface of a large borehole thermal energy store (BTES) has been investigated by coupling measured rock properties with an enhanced FEFLOW simulation.
Methods: The finite element model has been validated against measured data from a 2-year operation period. The thermal changes in the subsurface have been predicted by simulation for a 30-year operation period. The model is based on three 80-m core sections drilled in Triassic carbonates, which have been analyzed in detail with respect to lithology, facies, and thermal and hydraulic parameters.
Results: The model shows thermal effects of the BTES on the subsurface at a distance of approximately 350 m after 10 years and a distance of approximately 850 m after 30 years of operation. At a distance of 100 m, the temperature of the subsurface rises by 2 K after 30 years.
Conclusions: The simulation describes the real BTES in an accurate manner and is suited for predicting the thermal changes in the subsurface for long-term operational durations.
Methods: The finite element model has been validated against measured data from a 2-year operation period. The thermal changes in the subsurface have been predicted by simulation for a 30-year operation period. The model is based on three 80-m core sections drilled in Triassic carbonates, which have been analyzed in detail with respect to lithology, facies, and thermal and hydraulic parameters.
Results: The model shows thermal effects of the BTES on the subsurface at a distance of approximately 350 m after 10 years and a distance of approximately 850 m after 30 years of operation. At a distance of 100 m, the temperature of the subsurface rises by 2 K after 30 years.
Conclusions: The simulation describes the real BTES in an accurate manner and is suited for predicting the thermal changes in the subsurface for long-term operational durations.
| Original language | English |
|---|---|
| Journal | Geothermal Energy |
| Volume | 2 |
| Issue number | 1 |
| Early online date | 29 Apr 2014 |
| DOIs | |
| Publication status | Published - 1 Dec 2014 |
| Externally published | Yes |
Keywords
- borehole thermal energy store
- borehole heat exchanger system
- heat and mass trasnport model
- geothermal parameters
- Triassic carbonates