Massileo, the smart renewable energy network

Last modified by the author on 20/07/2018 - 09:32
  • Year of commitment : 2017
  • Address 1 - street : MARSEILLE, France
  • Green energies : Marine energy
  • Digital services : Smart grid

  • 10 000 000 €
  • Builder
    Optimal Solutions
  • Manager / Dealer

In Marseille, Optimal Solutions, a subsidiary of the Dalkia group EDF, designed and built Massileo ©, a thalassothermic network that produces heating, air conditioning and hot water from 75% renewable energies.
The network is composed of a tempered water loop that connects the calorie recovery plant on seawater - located on the port of Marseille - to the heat pumps installed in the basement of buildings.

This virtuous system allows buildings to exchange their calories. For example, the heat generated by the air conditioning of offices is recovered to produce domestic hot water and vice versa. 

Result: zero energy waste.

Since 2017, Massileo has been supplying the Smartseille eco-district with 58,000 m2 of offices, shops and housing. Tomorrow, the network will serve a much larger area, up to 500,000 m2.


  • 75% renewable energy and recovery
  • 80% less CO2
  • 21 MW of hot and cold production

Progress Status


Data Reliability

3rd part certified

Funding Type


Website Enterprise / Infrastructure

Sustainable Development

    A network to supply heating, air conditioning and domestic hot water 500,000 m2 of offices, shops and housing from 75% renewable energy.

    • Suppression of collective gas / oil boilers
    • Suppression of cold groups on the roofs of buildings
    • Reduction of noise pollution in buildings

    Stimulation of the local economic fabric.

    • 75% renewable energy and recovery
    • 80% less CO2

    Seawater is a renewable, stable and local energy.

    Seawater does not undergo any chemical treatment.


    Groupe EDF

    Private Company

    Optimal Solutions

    Power producer



    Project supported by the EDF group: design / implementation via its subsidiary Optimal Solutions and operation / maintenance via its subsidiary Dalkia.

    Project financed with European Union assistance via the ERDF, the European Regional Development Fund, ADEME, the French Environment and Energy Management Agency and the Caisse des Dépôts via the European Investment Program Future Investments.

Sustainable Solutions

    Energy transfer & Thalassothermie

    The energy system of the network is based on:

    • the transfer of energy between complementary buildings: the heat generated by the production of air conditioning for the offices is recovered for the production of domestic hot water of the houses;
    • the use of thalassothermy, the thermal energy of the sea: 100% renewable, local, abundant, reliable and compatible with the stakes of the operation; indeed, the temperature of seawater varies little and never reaches negative values;
    • a temperate water network between the source and the production plants located in each district where heat pumps allow the production of heating, air conditioning and hot water;
    • heating energy delivery substations located in the basements of buildings to meet the specific needs of each subscriber.

    • Energy/climate :
    • Infrastructure
    • Climate adaptation
    • Renewable energies
    • SmartGrids

Reasons for participating in the competition(s)

Comment valoriser une énergie renouvelable, locale et disponible toute l'année : la mer ?Massileo© le démontre en alimentant des bâtiments en chauffage, climatisation et eau chaude sanitaire par 75% d'EnR&R grâce à la récupération de calories sur la méditerranée.

Building candidate in the category

Users' Choice

Users' Choice

Sustainable Infrastructure Grand Prize

Sustainable Infrastructure Grand Prize

Green Solutions Awards 2018 - Infrastructures

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Author of the page

Christophe Rodriguez

Directeur Général Adjoint

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Green Solutions Awards 2018 - Infrastructures