The project, launched at the end of the first quarter of 2013, includes a two-year preliminary study phase followed by a five-year phase to demonstrate the two uses of hydrogen injection: NGV and residential

The French government is supporting the GRHYD hydrogen energy storage demonstrator project now being conducted by ENGIE and a consortium of industrial partners(2). France has set the target of meeting 23% of its gross end-user energy consumption from renewable sources by 2020. This ambitious project aims to convert surplus energy generated from renewable sources into hydrogen, which will then be blended with natural gas for a broad range of applications, including space heating, water heating and fuel. As a result, generators of energy from intermittent renewable sources, such as wind and solar power, will have a new solution for marketing the electricity they generate, at the same time as reducing greenhouse gas emissions.


Development of hydrogen in this way delivers a direct response to a series of energy and environmental challenges…

  • by helping to reduce greenhouse gas emissions
  • by promoting regional industrial expertise and natural resources
  • by supporting local economic development
  • by preparing for the introduction of hydrogen-powered vehicles



Power to gas: synthetic methane production architecture diagram

To evaluate the technical, economic and environmental relevance of Power-to-Gas, two demonstrators for this new energy solution are now up-and-running as part of a project involving local authorities and local residents in the Dunkerque Urban Community:

  • A transportation demonstrator
    The industrial scale Hythane® fuel project. A VNG bus fueling station will be adapted to handle the hydrogen/natural gas blend, which will begin with a 6% hydrogen content that will be increased over time to 20%. A fleet of around 50 buses will be operated using this hydrogen-natural gas blend.
  • A residential demonstrator
    A new residential neighborhood of around 200 homes in the Capelle la Grande district of the Dunkerque Urban Community will be supplied with a blend of hydrogen and natural gas using a variable hydrogen content of below 20%. Production will be based on energy from renewable sources (wind power) injected into the power distribution network. Surplus power will be used to produce hydrogen for storage and subsequent distribution to meet demand.


    Key target outcomes

    • Science / technology / innovation
      • The development of a Natural Gas/Hydrogen blend distributed via the natural gas supply network, and Hythane® fuels for vehicles and – indirectly – vehicles adapted to use these fuels
      • The development of innovative technologies: electrolyzers, storage technologies and hydrogen management (arbitrage), production and storage tools
    • Economy
      • Beneficial local effects for a broad range of businesses involved in everything from energy system design to maintenance
      • Encouraging the emergence of a source of new jobs for French hydrogen production and storage equipment suppliers and systems operators
    • Social
      • The ability to evaluate the social acceptability of using hydrogen as an energy solution for urban transportation and stationary applications
    • Environment
      • Reductions in Greenhouse Gas emissions and the health impacts of urban pollution on residents
      • The promotion of renewable and/or low carbon energy sources as a result of converted hydrogen being injected into the natural gas supply network

(1) A fuel containing hydrogen and natural gas
(2) A dozen industrial partners are working alongside ENGIE on the GRHYD demonstrator project.
They include GrDF, NVERT, AREVA Hydrogène et Stockage de l’énergie, CEA, McPhy Energy, INERIS, CETIAT and CETH2.