Drilling success at geothermal heat project in Vélizy-Villacoublay

Drilling success at geothermal heat project in Vélizy-Villacoublay Drilling rig at Velizy-Villacoublay, France (source: Engie Solutions)
Alexander Richter 26 Feb 2021

ENGIE Solutions and the City of Vélizy-Villacoublay have successfully completed drilling for a geothermal district heating system to supply heat to the equivalent of around 12,000 households.

Through their joint subsidiary Véligéo , the first SAS LTE (1) in Ile-de-France applied to geothermal energy, ENGIE Solutions and the City of Vélizy-Villacoublay announce that they have successfully completed geothermal drilling. The city is in the greater Paris area in France, southwest of the center of Paris.

Relying on the expertise of their main partners on this project, Schlumberger and the French drilling company SMP, the ENGIE Solutions teams designed and piloted the multi-drain drilling which began at the end of August 2020, achieving very positive results. These boreholes are an example of technological innovation serving the energy transition. They will allow the city’s heating network, Vélidis, to provide residents with heating and hot water with 66% renewable energy. Ultimately, the emission of 22,801 tonnes of CO 2 will be avoided each year.

Confirmed success of “multi-drains”, a first in Europe

Despite the pandemic context, the ENGIE Solutions teams and their partners met the deadlines without compromising on quality and safety. The first major step of this ambitious project, the geothermal drilling of 1,600 meters has just been finalized with results exceeding forecasts. This high-quality operation benefited from a sophisticated innovative exploration technique. Multi-drain drilling, associated with low-energy geothermal energy, was thus used for the first time in Europe.

Composed of three drains, the wellbore crosses three times the production levels and thus maximizes the volume of the reservoir drained naturally. The expected results are largely confirmed: while enhancing the potential of geothermal fabrics containing water (known as aquifers), this technique promotes the recovery of water at 65 ° C and provides a heat output of more than 16 MW. Based on the latest drilling technologies developed by Schlumberger, this innovative method made it possible to double the original production capacity by reaching up to 400 m 3 / hour.

This geothermal energy also preserves the sound comfort of the inhabitants and the quality of the air through the electrification of the drilling rig (the “rig”) of the SMP drilling company. This investment made by ENGIE Solutions enabled the first application in Ile-de-France of an “all-electric” site drastically reducing noise pollution with the added bonus of 550 tonnes of CO2 avoided.

Committed for 28 years between ENGIE Solutions and the City of Vélizy-Villacoublay, this partnership will provide heating and domestic hot water to the surrounding Velizian buildings and industrial premises, by drawing water from the basement to transform it into energy. .

An exemplary and promising project offering great prospects for the sector

The success of multi-drain drilling has been hailed by many players working in favor of the transition to a carbon neutral world. Representing a general investment of EUR 25 million, this project is supported by the Ile-de-France Region to the tune of EUR 3 million as part of the implementation of the regional energy-climate strategy.

In addition to its financial support, ADEME Ile-de-France selected the project as a demonstrator for the realization of the low-energy geothermal “doublet” and multi-drain technology.

Private R&D funding program and collaborative innovation platform, CITEPH (Concertation pour l’Innovation Technologique dans les Domaines des Energies) selected the project for the Open Innovation 2020 program. This innovative technique is fully in line with the ambition this program: bring out solutions that meet energy and environmental challenges, for more affordable, more reliable and cleaner energy.

The success of Véligéo’s drilling opens up three perspectives for the sector: it confirms a level of production in line with expectations for starting operations, calls for the development of this innovative solution for the deployment of geothermal energy in other territories in France, and optimizes production costs on historical farms.

“ENGIE Solutions has invested more than EUR 300 million in the sector in 10 years and carried out 20 low-energy geothermal boreholes 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. This project demonstrates our ability to mobilize all our know-how and technological resources with our partners to put them at the service of both the future comfort of Véliziens and the region’s energy transition ”.

“Schlumberger has the ambition to play a leading role in the field of energy transition by leveraging more than 90 years of expertise in advanced technologies associated with the exploration and production of energy. Geothermal energy is an energy 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 ”, declares Olivier Peyret, President of Schlumberger France .

“SMP has been present in geothermal energy since its creation in 1998 in the maintenance of geothermal wells and accelerated its desire to become a major in geothermal energy in France from 2012 by positioning itself in the drilling of new wells. SMP is proud to support ENGIE on its drilling projects by offering innovative technical and technological solutions to enable ENGIE to develop geothermal projects in ultra-urban environments as close as possible to their customers”, says Fabien Lemesnager Managing Director SMP .

Start of construction of the building

The end of the drilling allows the start of construction of the future geothermal power plant, which will consist of exchangers to recover heat from the wells and heat pumps to optimize production. The work should be completed this fall for the commissioning of geothermal energy by the end of the year.

At the same time, work to connect the boiler room to the Vélizy-Villacoublay heating network has started and will be completed this summer.

Véligeo – Key figures

  • 66% renewable energy
  • -1,600 m drilling depth
  • 2,400 m total length of shafts
  • 16 MW of heating capacity
  • 22,801 CO2, i.e. the equivalent of 15,000 vehicles avoided over time

The Vélizy district heating network – Key figures

  • 19 km
  • 140 delivery points
  • 12,000 housing equivalents

Note: (1) The Law of 17 August 2015 on the Energy Transition for Green Growth offered municipalities and inter-municipal authorities the possibility of participating in the capital of an SAS-LTE (energy transition law) whose corporate purpose is the production of renewable energies . Véligéo is the very first example of this in Île-de-France, launched in October 2019.

Source: Engie Solutions