Task 4.2 lead: FBK | Partners involved: ENGIE, SURREY, BH, UNIBO, BH, SNAM and ENAGAS
Alongside the development of the modelling method and tool, Task 4.2 is identifying and assessing practical measures to reduce hydrogen emissions across the value chain. Its first activity produced Deliverable D4.4, which provides a catalogue of mitigation strategies for the emission sources characterised in D4.1. Covering hydrogen production, transport, storage and end-use technologies, the work draws on published evidence, industrial practice and the technical expertise of the project partners. For each strategy, D4.4 describes how it could reduce fugitive, operational or other hydrogen emission pathways.
The current work builds directly on this catalogue. It converts the qualitative findings of D4.4 by quantifying the expected benefits of the identified mitigation actions. For Deliverable D4.5, each mitigation action is linked to the relevant D4.1 emission source or operating event and assessed against a representative industrial baseline. This will ensure that mitigation benefits are estimated consistently and only applied to the relevant emission pathways.
Partners assess the actions for the technologies they know best, using a shared Excel register for the structured technical data and a Word template for the supporting explanation. Where sufficient evidence is available, partners estimate low, central, and high mitigation impacts. Depending on the action, this may be expressed as a percentage reduction in hydrogen emissions, a lower mass per event, fewer purge or start-stop events, or a reduction in leak points. The same process records the evidence level, operating conditions, industrial maturity, and main economic implications. When reliable cost figures are unavailable, partners identify the expected cost class and the principal capital, operating, energy, maintenance, and validation requirements.
Table 1: Task 4.2 assessment workflow
| Step | Input or output | Purpose |
| 1 | D4.1 reference | Link each action to a defined hydrogen emission source or operating event |
| 2 | Activity 4.2.1 and D4.4 | Identify and qualitatively describe mitigation strategies across the value chain |
| 3 | Impact assessment for D4.5 | Estimate technical impact, evidence, applicability, industrial status and cost |
| 4 | WP4 tool decision | Integration into the WP4 tool |
The partners are currently assessing mitigation actions for a broad range of technologies, including: low-temperature electrolysis, stationary and mobility fuel cells, compressors, transmission grids, compressed and liquefied hydrogen tanks, underground storage and hydrogen refuelling stations. The results will provide a consistent picture of the expected technical impact, uncertainty, industrial applicability and economic implications of each action. They will also provide the WP4 tool with a transparent set of mitigation options for exploring scenarios across the complete hydrogen value chain and support their subsequent implementation and assessment in Task 4.3.
