Thassalia: inauguration of France's first marine geothermal power station

By ENGIE - 18 October 2016 - 12:53

Thassalia: inauguration of France's first marine geothermal power station

A leader in energy transition, ENGIE creates sustainable solutions to meet people energy requirements, all while remaining environmentally friendly.

Gérard Mestrallet, chairman of ENGIE's board of directors, inaugurated the new marine geothermal power station Thassalia last evening. The event took place in the presence of Stéphane Bouillon, prefect of the Provence-Alpes-Côte d'Azur (PACA) region and prefect of the Bouches-du-Rhône region; Renaud Muselier, delegated president of the PACA region and member of the European Parliament; Solange Biaggi, president of the Bouches-du-Rhône departmental council and first vice president of the Greater Aix-Marseille-Provence authority; Laure-Agnès Caradec, president of the Euroméditerranée initiative and deputy mayor of Marseille; and Christine Cabau-Woehrel, president of Marseille Fos Port’s board; under the high patronage of Jean-Claude Gaudin, president of the Greater Aix-Marseille-Provence authoritymayor of Marseille, and vice president of the senate and Christian Estrosi, president of the PACA region.


The sea as an energy source: Thassalia, an innovative and sustainable project


In Marseille, a new solution has been developed to take advantage of the locally available renewable energy: using the calorific energy held in the Mediterranean Sea. The project is a real example of innovation that allows for energy transition and efficiency, therefore consistent with plans to make the Euroméditerranée quarter an example of a sustainable city. Built at the Marseille-Fos Port, the marine geothermal power station Thassalia is the first in France, and even in Europe, to use the sea's thermal energy to supply linked buildings with power for heating and cooling — over an area which will eventually comprise 500,000m² — while reducing greenhouse gas emissions by 70%.


"The Thassalia inauguration is an opportunity for me to appreciate the involvement of this beautiful region in energy transition, especially in terms of renewable energy development and continued commitment to improve building energy efficiency. The marine geothermal power station serves as a new innovative display of this approach. Thanks to its strong local presence and a wide range of expertise, ENGIE - a leader in energy transition - accompanies such projects taking into account the various territorial challenges," states Isabelle Kocher, CEO of ENGIE.


ENGIE's innovative solution was brought to life through the expertise of its subsidiaries, ENGIE Cofely for thermal matters, and Climespace for district cooling. All the technical elements of the power station were created by the company's teams; Ineo and Cofely handled electricity, Axima and Cofely covered internal networks, and Axima also provided half of refrigeration units.


A three-kilometre network will provide energy for the buildings during construction and renovation of the zone, spanning from the CMA-CGM Tower to the Marseille Cathedral. Currently, the connected buildings are the Docks (Constructa), the Calypso and the Hermione (Euromedcenter), and the Golden Tulip. Soon will come the Constructa towers: the Marseillaise, the Floreal (Euromedcenter), Castel, and the Parc Habité d'Arenc, whose main client will be Nexity.



  • 35 million Euros of investments

  • 500 000 m² of buildings supplied between 2015-2020

  • A grid of 3 kilometres

  • 70% of renewable energy

  • 70% reduction of greenhouse gas emissions


ENGIE develops its businesses (power, natural gas, energy services) around a model based on responsible growth to take on the major challenges of energy’s transition to a low-carbon economy: access to sustainable energy, climate-change mitigation and adaptation and the rational use of resources. The Group provides individuals, cities and businesses with highly efficient and innovative solutions largely based on its expertise in four key sectors: renewable energy, energy efficiency, liquefied natural gas and digital technology. ENGIE employs 154,950 people worldwide and achieved revenues of €69.9 billion in 2015. The Group is listed on the Paris and Brussels stock exchanges (ENGI) and is represented in the main international indices: CAC 40, BEL 20, DJ Euro Stoxx 50, Euronext 100, FTSE Eurotop 100, MSCI Europe, DJSI World, DJSI Europe and Euronext Vigeo (Eurozone 120, Europe 120 and France 20).