20.500.12556/DKUM-90420 Numerical analysis of low-enthalpy deep geothermal energy extraction using a novel gravity heat pipe design Geothermal energy, derived from the Earth’s internal heat, can be harnessed due to the geothermal gradient between the Earth’s interior and its surface. This heat, sustained by radiogenic decay, varies across regions, and is highest near volcanic areas. In 2020, 108 countries utilised geothermal energy, with an installed capacity of 15,950 MWe for electricity and 107,727 MWt for direct use in 2019. Low-enthalpy sources require binary systems for power production. Open-loop systems face issues like scaling, difficult water treatment, and potential seismicity, while closed-loop systems, using abandoned petroleum or gas wells, reduce costs and environmental impacts greatly. The novel geothermal gravity heat pipe (GGHP) design eliminates parasitic power consumption by using hydrostatic pressure for fluid circulation. Implemented in an abandoned well in north-east (NE) Slovenia, the GGHP uses a numerical finite difference method to model heat flow. The system vaporises the working fluid in the borehole, condenses it at the surface, and uses gravitational flow for circulation, maintaining efficient heat extraction. The model predicts that continuous maximum capacity extraction depletes usable heat rapidly. Future work will explore sustainable heat extraction and potential discontinuous operation for improved efficiency. geothermal energy geothermal gravity heat pipe numerical modelling single well closed-loop heat exchanger geotermalna energija geotermalana gravitacijska toplotna cev numerično modeliranje true false true MDPI Angleški jezik Slovenski jezik https://www.mdpi.com/journal/sustainability © 2024 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/). Članek v reviji 2024-09-03 13:01:54 2024-09-03 13:01:55 2026-02-03 03:14:27 0000-00-00 00:00:00 2024 0 0 13 str. iss. 15, [article no.] 6660 Vol. 16 Aug. 2024 0000-00-00 Zaloznikova Objavljeno NiDoloceno 2024-05-28 2024-07-31 2024-08-03 620.92/.98 206210051 10.3390/su16156660 2071-1050 sustainability-16-06660.pdf sustainability-16-06660.pdf 1 18A9666B96223759D4E0B29342903150 a2f2a4905fcd8469c05beb707a7802c7213367b460e4b48b70f601e16d04eeed cce409cd-0016-11f1-90fc-00155d581219 https://dk.um.si/Dokument.php?lang=slv&id=202956 https://www.mdpi.com/2071-1050/16/15/6660 0 d5ac6332-0016-11f1-90fc-00155d581219 https://dk.um.si/Dokument.php?lang=slv&id=202957 Fakulteta za kemijo in kemijsko tehnologijo 0 0 0