Periodic Reporting for period 3 - DEEPEGS (DEPLOYMENT OF DEEP ENHANCED GEOTHERMAL SYSTEMS FOR SUSTAINABLE ENERGY BUSINESS)
Berichtszeitraum: 2018-12-01 bis 2020-04-30
The first DEEPEGS demonstrator at Reykjanes (WP6) drilling was was completed 25th January 2017, at 4659 m (i.e. 4650 m from surface). Supercritical conditions (426°C at 340 bar) had already been measured during drilling, 3d January 2017, at 4550 m depth after only 5-6 day heating. A perforated 7” liner was inserted down to 4591.2 m depth, and a 7” sacrificial casing from surface to 1303.7 cemented in. This was followed by deepening of the hole by 6” bit, using the 3 ½” stimulation drill string, from 4624-4636 m (pilot hole), and then by three successive spot core drilling using 6” coring tools from Baker Hughes, reaching final depth of 4659 m (i.e. 4650 m from surface). The 3 ½” stimulation string was subsequently lowered into the hole for deep stimulation. Soft stimulation by repeated heating and cooling of the lower part of the hole for a while, followed by inserting a 3 ½” drill pipes for deep stimulation which kept on going until project month 20 (July 2017). After that cold water injection kept on going until project month 33 (August 2018), followed by hot water injection until month 34. Since then the well has been allowed to heat up in preparation for discharge testing in 2019.
The second DEEPEGS demonstrator is at Vendenheim (WP7) in the Alsace region of France became part of the project in December 2018. Fonroche Geothermie (FG) had started the drilling operations in Vendenheim in June 2017.
The Rhine Graben has had several projects and experimentation done, there is still an unknown part nearby Strasbourg, where no geothermal project had been done and no project had been drilled in this region at this target’s depth of around 5 km.
Despite having some preliminary results about what the geological environment in Vendenheim form earlier available geological studies, the width of the sedimentary basin met in VDH was unknown. The bottom of this basin was 500 m deeper than anticipated and with a large Permian layer that none of the pre-existing data had predicted. The temperature reached in VDH was higher than initially anticipated (185°C) and reached a measured temperature of 225°C.
The FG seismic network had been augmented by KIT with additional seismometers, and BRGM and KIT had added Controlled-source EM and MT monitoring in the Vendenheim field. Geochemical monitoring (BRGM and FG) completed the set of survey for a better understanding of the reservoir.
DEEPEGS has produced numerous outreach and dissemination actions during its 53 months project life-cycle. The publications have been collated into a Book of Publications that can be accessed at this link; https://deepegs.eu/book-of-publications-2020/.
The project consortium will continue disseminating new results from the project and these and currently published reports will be accessible from this link; https://deepegs.eu/publications/.
The final meeting on 24 April 2020 was webcast and the recording with presentations are publicly available here; Link: https://deepegs.eu/final-meeting-outcomes/.
In France the Vendenheim demonstration site has produced evidence of measured temperature of 225°C, which is considerably higher than expected. The well flow testing has unfortunately been delayed due to the COVID-19 pandemic in last project months in 2020. Therefore, the full results for the VDH site performance will only become available after end of the DEEPEGS project. The main socio-economic impact and societal effects and acceptance can be measured by the dissemination and communication to the industry, research institutes and universities outside the consortium. The project worked on communication to the public and how geothermal projects can be managed to minimize concerns like those commonly arising in mainland Europe about induced seismic events.