Design Considerations for Borehole Thermal Energy Storage (BTES): A Review with Emphasis on Convective Heat Transfer
Borehole thermal energy storage (BTES) exploits the high volumetric heat capacity of rock-forming minerals and pore water to store large quantities of heat (or cold) on a seasonal basis in the geological environment. The BTES is a volume of rock or sediment accessed via an array of borehole heat exc...
Saved in:
| Main Authors: | , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Wiley
2019-01-01
|
| Series: | Geofluids |
| Online Access: | http://dx.doi.org/10.1155/2019/4961781 |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1832565743531589632 |
|---|---|
| author | Helge Skarphagen David Banks Bjørn S. Frengstad Harald Gether |
| author_facet | Helge Skarphagen David Banks Bjørn S. Frengstad Harald Gether |
| author_sort | Helge Skarphagen |
| collection | DOAJ |
| description | Borehole thermal energy storage (BTES) exploits the high volumetric heat capacity of rock-forming minerals and pore water to store large quantities of heat (or cold) on a seasonal basis in the geological environment. The BTES is a volume of rock or sediment accessed via an array of borehole heat exchangers (BHE). Even well-designed BTES arrays will lose a significant quantity of heat to the adjacent and subjacent rocks/sediments and to the surface; both theoretical calculations and empirical observations suggest that seasonal thermal recovery factors in excess of 50% are difficult to obtain. Storage efficiency may be dramatically reduced in cases where (i) natural groundwater advection through the BTES removes stored heat, (ii) extensive free convection cells (thermosiphons) are allowed to form, and (iii) poor BTES design results in a high surface area/volume ratio of the array shape, allowing high conductive heat losses. The most efficient array shape will typically be a cylinder with similar dimensions of diameter and depth, preferably with an insulated top surface. Despite the potential for moderate thermal recovery, the sheer volume of thermal storage that the natural geological environment offers can still make BTES a very attractive strategy for seasonal thermal energy storage within a “smart” district heat network, especially when coupled with more efficient surficial engineered dynamic thermal energy stores (DTES). |
| format | Article |
| id | doaj-art-c3d161c091374176879c83ea1813aefc |
| institution | Kabale University |
| issn | 1468-8115 1468-8123 |
| language | English |
| publishDate | 2019-01-01 |
| publisher | Wiley |
| record_format | Article |
| series | Geofluids |
| spelling | doaj-art-c3d161c091374176879c83ea1813aefc2025-02-03T01:06:55ZengWileyGeofluids1468-81151468-81232019-01-01201910.1155/2019/49617814961781Design Considerations for Borehole Thermal Energy Storage (BTES): A Review with Emphasis on Convective Heat TransferHelge Skarphagen0David Banks1Bjørn S. Frengstad2Harald Gether3Gether AS, Bakkeveien 12, N-3292 Stavern, NorwaySchool of Engineering, James Watt Building (South), Glasgow University, Glasgow G12 8QQ, UKDepartment of Geoscience and Petroleum, Norwegian University of Science and Technology (NTNU), N-7491 Trondheim, NorwayGether AS, Bakkeveien 12, N-3292 Stavern, NorwayBorehole thermal energy storage (BTES) exploits the high volumetric heat capacity of rock-forming minerals and pore water to store large quantities of heat (or cold) on a seasonal basis in the geological environment. The BTES is a volume of rock or sediment accessed via an array of borehole heat exchangers (BHE). Even well-designed BTES arrays will lose a significant quantity of heat to the adjacent and subjacent rocks/sediments and to the surface; both theoretical calculations and empirical observations suggest that seasonal thermal recovery factors in excess of 50% are difficult to obtain. Storage efficiency may be dramatically reduced in cases where (i) natural groundwater advection through the BTES removes stored heat, (ii) extensive free convection cells (thermosiphons) are allowed to form, and (iii) poor BTES design results in a high surface area/volume ratio of the array shape, allowing high conductive heat losses. The most efficient array shape will typically be a cylinder with similar dimensions of diameter and depth, preferably with an insulated top surface. Despite the potential for moderate thermal recovery, the sheer volume of thermal storage that the natural geological environment offers can still make BTES a very attractive strategy for seasonal thermal energy storage within a “smart” district heat network, especially when coupled with more efficient surficial engineered dynamic thermal energy stores (DTES).http://dx.doi.org/10.1155/2019/4961781 |
| spellingShingle | Helge Skarphagen David Banks Bjørn S. Frengstad Harald Gether Design Considerations for Borehole Thermal Energy Storage (BTES): A Review with Emphasis on Convective Heat Transfer Geofluids |
| title | Design Considerations for Borehole Thermal Energy Storage (BTES): A Review with Emphasis on Convective Heat Transfer |
| title_full | Design Considerations for Borehole Thermal Energy Storage (BTES): A Review with Emphasis on Convective Heat Transfer |
| title_fullStr | Design Considerations for Borehole Thermal Energy Storage (BTES): A Review with Emphasis on Convective Heat Transfer |
| title_full_unstemmed | Design Considerations for Borehole Thermal Energy Storage (BTES): A Review with Emphasis on Convective Heat Transfer |
| title_short | Design Considerations for Borehole Thermal Energy Storage (BTES): A Review with Emphasis on Convective Heat Transfer |
| title_sort | design considerations for borehole thermal energy storage btes a review with emphasis on convective heat transfer |
| url | http://dx.doi.org/10.1155/2019/4961781 |
| work_keys_str_mv | AT helgeskarphagen designconsiderationsforboreholethermalenergystoragebtesareviewwithemphasisonconvectiveheattransfer AT davidbanks designconsiderationsforboreholethermalenergystoragebtesareviewwithemphasisonconvectiveheattransfer AT bjørnsfrengstad designconsiderationsforboreholethermalenergystoragebtesareviewwithemphasisonconvectiveheattransfer AT haraldgether designconsiderationsforboreholethermalenergystoragebtesareviewwithemphasisonconvectiveheattransfer |