Multilateral well design for geothermal heat project, France

Drilling rig at Velizy-Villacoublay, France (source: Engie Solutions)

Earlier this year, we reported on the successful drilling campaign for the geothermal heating project by ENGIE  Solutons in Vélizy-Villacoublay, France.

In the collaboration for the  project ENGIE Solutions, Schlumberger and SMP Drilling completed drilling of a 1,600-meter deep well, to enable an innovative heating solution for the city. The multilateral well design, which is the first of its kind for a geothermal application in France, was drilled using the PowerDrive Archer* high build rate rotary steerable (RSS) system and AxeBlade (TM) ridged diamond element bit.

The geothermal well will enable the French city’s heating network, Vélidis, to provide heating and hot water supply to 16,000 homes with more than 60% renewable energy. In the long term, this heating solution is expected to reduce CO2 emissions by 22,801 tons each year.

“Schlumberger has the ambition to play a leading role in the energy transition by leveraging more than 90 years of expertise in advanced technologies associated with the exploration and production of energy,” said Olivier Peyret, Schlumberger Chairman France & New Energy Europe Director. “Geothermal energy is a resource that has extraordinary advantages both in terms of its efficiency and its ability to reduce our impact on the environment. We are particularly proud to have contributed to this project, which demonstrates the importance of working within the framework of an ecosystem where everyone contributes their know-how for the benefit of a successful energy transition.”

“ENGIE Solutions has invested more than EUR 300 million in the sector in 10 years and carried out 20 low-energy geothermal drilling operations over the same period,” underlines Aurélie Lehericy, Deputy Managing Director of ENGIE Solutions Villes & Collectivités.

“It is a source of pride for us to support the City of Vélizy-Villacoublay in this particularly exemplary project; the drilling results speak for themselves. With Schlumberger, our partner on this project, we have mobilized all our know-how and our technological resources, serving both the future comfort of the Véliziens and the region’s energy transition.”

The drilling project comprised a multilateral reservoir section with high dogleg severity (DLS) in the curves where the main wellbore branches off into three distinct boreholes. The individual borehole branches intersect the producing zones of the reservoir multiple times, thus improving the well’s overall productivity. The well profile design enhances the potential of geothermal fabrics containing water (known as aquifers), promoting the recovery of water at 65 degrees Celsius and providing a heat output of more than 16 MW.

The PowerDrive system, which is well-suited for high-DLS wells, enabled this innovative geothermal well profile, effectively doubling the original production capacity by reaching up to 400 m3/h. The fit-for-basin AxeBlade bit contributed to delivery of the reservoir section ahead of schedule.

Source: Company release