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Systematic validation of the ability to inject hydrogen at various admixture level into high-pressure gas networks in operational conditions


The potential project should address the development, and subsequent operation of a research and development platform reproducing all the components of a high-pressure network and allowing testing of various accessories and appliances for various H2/CH4 admixtures:

  • It should validate levels of admixtures compatible with the technical elements of the existing high-pressure gas grid (approx. 40 to 80 bars), and high-pressure industrial users equipment (not addressed by the topic FCH-04-3-2019: Hydrogen admixtures in natural gas domestic and commercial end uses). In particular it should provide knowledge to support the adaption of maintenance procedure for a safe operation of the high-pressure gas network with regards to different levels of H2/CH4 admixture;
  • It should validate the industrialization of innovations necessary to make the whole existing gas system (pipeline, fittings, but also industrial end users’ equipment) compatible with these admixtures (e.g. gas quality steering through the mixing equipment, inspection tools etc.).

The project should fill the technical gaps identified by several stakeholders, in particular for high-pressure grid. The scope of the research and development platform should be based on the gap analysis of the main barriers in the state-of-the-art technology and standardisation identified by the Working Group Hydrogen from the Sector Forum Energy Management (SFEM).

It is therefore expected that the project would deliver:

  • An impact assessment concerning the use of H2 in various percentage mixed with natural gas (up to 100% H2); this should also embrace the associated fittings and other components for all of the technologies within the high-pressure gas networks;
  • A fact-based assessment of the roles of these technologies in integrating H2 and CH4 energy systems at EU level thanks to economic modelling and identification of legal aspects on inter-operability and cross-border regulatory issues;
  • Pre-normative research actions leading to standardisation at EU level.

Moreover, it is also expected that the admixture facility would:

  • Have a capacity of injecting equal or greater than 5 kg/h of hydrogen at full load into the test loop;
  • Operate with concentrations from 0 to 100% hydrogen with various ramp rates, response times and pressure cycles;
  • Operate with transient gas characteristics and flow rate (depending on sources - natural gas, new generation biomethane etc.);
  • Have precise measurement and control of the hydrogen concentration in the injected gas, whereby the solution must be scalable and easily applied at high pressure level and for various concentration limits;
  • Be able to accommodate various tests or certification programs, including on network equipment, appliances and coatings.

While the test loop should be used to:

  • Test (high pressure > 40 bar) gas network equipment that could be impacted by the presence of hydrogen, as identified by the consortium, and present necessary changes to equipment and/or maintenance procedures;
  • Define principles and improve the design of hydrogen injection and mixing system in line with network behaviour. An optimum design should be published to establish a solid basis for hydrogen injection systems across EU;
  • Test separation systems to meet cases where some users’ process cannot accommodate the presence of hydrogen. Focus should be placed on streams where hydrogen is present in small concentrations (lower than 15%), since for high concentrations present Pressure swing adsorption (PSA) technology is already optimized.

From the regulatory perspective, it is expected that the potential project would also:

  • Identify the legal aspects, cross-border regulatory issues and support schemes and European green certificates schemes that hinder or enable the adoption of various H2NG blends across Europe and give recommendations for alterations where needed;
  • Identify issues related to managing the energy system (both physical and commercial, including use of certificates) across Member States and identify the necessary roles in system management;
  • Develop and publish a pathway for a stepwise integration of hydrogen in the EU gas network.

Safety of the whole hydrogen chain, from the injection in gas network, to the gas metering, leakage detection, pipeline inspection should be the main technical objective and goal of the platform. For example, technical specifications on the use of components of the network, based on tests performed in the platform will allow the injection of hydrogen in gas network while improving safety. Better knowledge of hydrogen impact on pipeline integrity is needed to know or insure the compatibility of existing gas network with hydrogen transmission and adaptions of gas network control and maintenance procedures.

TRL at start: 4 and TRL at the end of the project: 6.

Any safety-related event that may occur during execution of the project shall be reported to the European Commission's Joint Research Centre (JRC) dedicated mailbox , which manages the European hydrogen safety reference database, HIAD and the Hydrogen Event and Lessons LEarNed database, HELLEN.

Test activities should collaborate and use the protocols developed by the JRC Harmonisation Roadmap (see section 3.2.B ""Collaboration with JRC – Rolling Plan 2019""), in order to benchmark performance of components and allow for comparison across different projects.

The FCH 2 JU considers that proposals requesting a contribution of EUR 2 million would allow the specific challenges to be addressed appropriately. Nonetheless, this does not preclude submission and selection of proposals requesting other amounts.

A maximum of 1 project may be funded under this topic.

Expected duration: 3 years.

Hydrogen can play a pivotal role, either being produced by electrolysis as a service to the electricity grid (sector coupling) or produced on purpose for decarbonization of hard-to-electrify sectors (e.g. individual heat, and long-range mobility).

There is presently no harmonized and systematic approach across EU regarding the ability to inject hydrogen into the high-pressure gas network, and various European operators display non-consistent hydrogen admission rates. This un-clarity strongly hinders the ability of projects promoters to de-risk their project using the option to evaluate their excess hydrogen production into the organized Integrated Energy gas Market (IEM), and hinders policy makers when trying to properly assess the potential role of hydrogen for sector coupling and in the energy transition at large.

The topic aims at establishing and documenting that hydrogen injection into the EU wide high-pressure gas infrastructure is a long-term sustainable solution, supporting not only sector coupling between electricity and gas, but also opening the role of hydrogen as a cost-efficient decarbonization mean for gas usages [1]; this is in line with the European Commission proposal to update the EU Gas Directive to improve the functioning of the EU internal gas market, increase competition between suppliers, and boost Europe's energy security.

In existing power-to-gas demonstration projects, hydrogen is injected locally into the low-pressure distribution grid or in very specific higher-pressure locations. This solution, although necessary in the short run and appropriate for projects of a limited injection rate, cannot address a scale up of hydrogen production. In particular, injection of hydrogen in the low-pressure grid as a mix is limited by the limited size of demand in summer and the acceptable methane/hydrogen ratio. This has been already documented as a challenge e.g. for biomethane injection. Conversely, a total conversion of a low-pressure grid to pure hydrogen usage requires a replacement of almost all end-users’ appliances, and is conditioned by the vicinity of specific geological formations (salt caverns) to address the swing in production and demand.

The challenge for this topic is to enable injection of hydrogen into the high-pressure gas transmission network safely at industrial scale, addressing both the issue of scalability (ability to decarbonize the gas usages in all their aspects), and marketability/bankability of projects (accessing the IEM for excess hydrogen). In the absence of an answer to the CH4/H2 admixture possibility, hydrogen use will be restricted to limited niches, leading to a market fragmentation and inefficiency of energy use.

The ability to operate the gas system in a mixed hydrogen/methane environment relies on assessing systematically and in an EU harmonized way the technical adaptions, which have to be made in the operating and maintenance processes, materials, admixture steering etc. across the whole system. In this respect, the technical and legal framework is lacunar, and has to be specified and harmonized across EU. Technical specifications on the network and components of the network should be defined based on facts established through scientific knowledge, lab and larger scale test.

[1]: At EU level, gas usage is presently representing 22% of Final Energy Consumption (20% electricity), and various studies have proven that a 100% electricity FEC solution would be unnecessarily costly

The project is expected to support acceleration for the implementation of power-to-gas systems by solving technical barriers and initiating the removal of legal and regulatory barriers to injection of hydrogen in the gas transmission network. This will enable hydrogen produced at sites during periods of excess renewable power to be sold in countries with lower availability of renewable power, even if these places are in a different EU country. As a consequence, it will be supportive of renewable electricity production integration, but also of a deep decarbonisation of the gas usages.

The platform developed by the project will validate the technical, legal, regulatory conditions for safe operation of the gas transmission system, supporting the integration of hydrogen “at scale” in the EU-wide gas system, and therefore in the Integrated Energy Market. Operators’ and market-players’ responsibilities, and mechanisms for dealing and managing the energy system across at least two EU Member States will be identified, and help develop transnational knowledge exchange towards an optimal (stepwise) integration of H2 and CH4.

The project should aim to improve the understanding of the impacts of admixtures on the high pressure transmission grid and related equipment, complementing the knowledge produced by the other two related topics of this call (topic FCH-02-1-2019: Combined electrolyser-HRS and Power-to-Gas system and topic FCH-04-3-2019: Hydrogen admixtures in natural gas domestic and commercial end uses).

It is further expected that the equipment installed during the project will remain available for long-term R&D work into gas grid injection, and made available free to EU stakeholders outside the consortium, as a basis for further development while hydrogen production gets traction across Europe.

Type of action: Research and Innovation Action

The conditions related to this topic are provided in the chapter 3.3 and in the General Annexes to the Horizon 2020 Work Programme 2018– 2020 which apply mutatis mutandis.