The EU’s Hydrogen Strategy^[1], REPowerEU^[2] and other relevant European initiatives, clearly recognise clean hydrogen and its applications as a fundamental pillar of the future European energy system, supporting the energy, industrial and mobility sectors in reaching the EU’s ambitious decarbonisation targets. Hydrogen can strongly contribute to the reduction of carbon emissions as it can be produced from renewable energy sources and, when it is consumed, does not emit CO₂. As such, a hydrogen molecule present in the atmosphere does not act as a direct greenhouse gas as it does not have a dipole moment. However, hydrogen can react with other molecules present in the atmosphere (mainly hydroxyl radicals) and increase the lifetime of methane, increase the production rate of ozone and water vapour, thus acting as an indirect greenhouse gas. As it has been widely discussed during the Clean Hydrogen JU Expert Workshop on the Environmental impacts of Hydrogen and reported in the workshop summary report^[3], it is therefore crucial to assess that potential hydrogen releases along the entire hydrogen value chain do not have an overall material negative impact on the environment and consequences on the climate.

To date, there is still uncertainty considering the amount of the hydrogen releases expected along the future hydrogen value chains.

The results of the project should allow the scientific and industrial community to understand the practical releases rates (which include all types of anthropogenic emissions – fugitive emissions, technical vents, depressurisation, etc.) across the hydrogen value chain, in order to further assess the potential effects of a hydrogen economy on the climate.

Project results are expected to contribute to all of the following expected outcomes:

• Identification, quantification, and preparation of an inventory of the types of anthropogenic hydrogen releases expected throughout the hydrogen value chains, including production, handling (e.g., compression, liquefaction, packing into hydrogen carriers, purification), transport and distribution, storage and final uses, in the short (2030) and long term (2050);
• Identification and ranking of the main elements of the hydrogen value chain in terms of the estimated hydrogen release and definition of potential mitigation strategies;
• Simulation and forecasting models of hydrogen releases along the hydrogen value chains for the quantification of the hydrogen releases;
• Identification and investigation of potential measuring technologies to detect and quantify hydrogen releases.

Project results (such as guidelines, methodologies, databases, modelling tools and/or spreadsheets for hydrogen release estimation, experimental results, etc.) are expected to contribute to all of the following objectives and targets of the Clean Hydrogen JU SRIA:

• Develop eco-design guidelines and eco-efficient processes that limit hydrogen releases;
• Increase the level of safety of hydrogen technologies and applications;
• Support the development of RCS for hydrogen technologies and applications, with the focus on standards, for assessing the hydrogen releases of the growing H₂ value chain;
• Contribute to the SRIA target by organising safety, PNR/ RCS workshops.

Contribute to the SRIA target by providing inputs for developing Standards, Technical Specifications, or Technical Reports.

The natural gas industry has for decades been strongly committed to identifying, quantifying, and mitigating gas releases along the entire value chain, from production (extraction) to final uses. In addition, the effects of releases of gases in the environment have been widely studied and assessed, with the aim of limiting the climate-change effects as much as possible.

While methane emissions is a well-known topic, with emission quantification methods/technologies and mitigation strategies defined, the case of hydrogen is different, as there are no indications/guidelines that exhaustively cover all the different elements of the hydrogen value chain. This case requires in-depth analysis, supported by experimental campaigns, in order to understand the potential leakage rates of hydrogen across its value chain and assess the overall hydrogen releases of a large adoption of this energy vector. The Clean Hydrogen JU Expert Workshop on Environmental Impacts of Hydrogen and the workshop summary report represent a valuable analysis and should be used as reference^[3].

Building also on the experience gained in the natural gas sector and on the characterisation of methane emissions, the proposals should therefore assess the potential hydrogen releases of the future hydrogen value chains.

In order to assess the potential hydrogen release, the proposals should:

• Identify, classify, quantify and prepare an inventory of the types of anthropogenic hydrogen releases expected throughout the hydrogen chain, including production, handling (e.g., compression, liquefaction, packing into hydrogen carriers, purification), transport and distribution, storage, and final uses;
• Identify the most critical elements of the hydrogen chain with regard to potential hydrogen releases considering the different building blocks (e.g., production, handling, etc.);
• Develop and validate appropriate methodologies and test methods and protocols to provide the required data on releases of hydrogen from the most critical elements of the hydrogen value chain. Methods are needed which fulfil similar roles as in the existing natural gas supply chain. These may include methods to enable the identification of sources of hydrogen releases (for example as in leak detection, maintenance and repair programmes), to quantify the mass emission rates of releases into the atmosphere, and to provide test methods to characterise the performance of equipment for hydrogen use. The methods and protocols should be developed considering the potential for future standardisation;
• Identify the total potential hydrogen releases along the whole hydrogen value chain, considering the different building blocks (e.g., production, handling, end-uses, etc.). The proposals should develop simulation tools able to characterise the total potential hydrogen releases considering the different hydrogen scenarios;
• Identify mitigation measures, engineering solutions, technologies, research and development actions to minimise the release of hydrogen.

Building on the results of the previous activities, the proposals should provide recommendations and dissemination for updating and/or development of new standards at the EU and International levels.

Research and experimental activities, including the industry contributions, should support the scientific community in the assessment of the quantification of the potential impact of the hydrogen release from the hydrogen value chain on the climate, providing data and tools for the quantification of the total hydrogen released. It is strongly recommended that the proposals complement (and include a reference on the synergy approach) the topic published in the Horizon Europe Work Programme 2023-2024 Cluster 5, HORIZON-CL5-2023-D1-01-03: Climate impacts of a hydrogen economy^[5] and that its results should be used to assess the potential environmental impact of a hydrogen economy.

Cooperation with EU and International entities and institutions on climate, atmospheric and meteorological expertise, as well as normative and standardisation entities, is strongly encouraged. In particular, proposals are expected to collaborate and explore synergies with the activities of EURAMET’s European Metrology Networks^[6] (e.g Decarb project^[7]).

Given the scope of this topic, the involvement of formal standardisation bodies as part of the consortia is encouraged, with the aim of facilitating the uptake of the project results.

Proposals are expected to contribute towards the activities of Mission Innovation 2.0 - Clean Hydrogen Mission. Cooperation with entities from Clean Hydrogen Mission member countries, which are neither EU Member States nor Horizon Europe Associated countries, is encouraged (see section 2.2.6.7 International Cooperation).

The JU estimates that an EU contribution of maximum EUR 3.00 million would allow these outcomes to be addressed appropriately.

Beneficiaries must, up to 4 years after the end of the action, inform the granting authority if the results could reasonably be expected to contribute to European or international standards.

The conditions related to this topic are provided in the chapter 2.2.3.2 of the Clean Hydrogen JU 2023 Annual Work Plan and in the General Annexes to the Horizon Europe Work Programme 2023–2024 which apply mutatis mutandis.

[1] A Hydrogen Strategy for a climate neutral Europe. COM(2020) 301 final

[2] https://eur-lex.europa.eu/legal-content/EN/TXT/?uri=COM%3A2022%3A230%3AFIN&qid=1653033742483

[3] JRC Report: Hydrogen emissions from a hydrogen economy and their potential global warming impact. Link: https://publications.jrc.ec.europa.eu/repository/handle/JRC130362

[4] JRC Report: Hydrogen emissions from a hydrogen economy and their potential global warming impact. Link: https://publications.jrc.ec.europa.eu/repository/handle/JRC130362

[5] https://ec.europa.eu/info/funding-tenders/opportunities/portal/screen/programmes/horizon

[6] https://www.euramet.org/european-metrology-networks

[7] https://www.euramet.org/european-metrology-networks/energy-gases/activities-impact/projects/project-details/project/metrology-for-decarbonising-the-gas-grid