Interview-based survey of current best-practice solutions in dealing with hydrogen quality in Germany

Background

• Coordinating the quality of hydrogen is of central importance for the development of the future hydrogen economy. This is because the purity of the hydrogen produced varies depending on the source, and the requirements of different users differ depending on the intended use.

• Frontier Economics and DBI Gas- und Umwelttechnik GmbH have conducted a study on behalf of industry initiative GET H2 and DVGW, a recognized standardization body for the gas and water industry in Germany. The aim was to identify best-practice solutions for the first commercial hydrogen projects in Germany by 2027. Particular attention was paid to hydrogen quality in the areas of production, transport and storage.

The handling of hydrogen qualities is assessed differently at different stages of the value chain. In doing so, technical feasibility, practical and economic aspects need to be considered.

• Production: The quality of the hydrogen produced or imported varies depending on the technology used. Both electrolysis and imports via ammonia can be used to achieve a quality that exceeds the current Grade A standard (which requires a hydrogen purity of “only” 98.0%).

• Transport: For the use of new pipelines, operators do not expect any significant additional impurities from transport, which means thathigh quality (Grade D, which requires hydrogen purity of 99.97%) can be guaranteed, even in the short term. In pipelines converted from natural gas to hydrogen, higher levels of contamination are expected in the short term, but these will decrease over time. Although network operators cannot guarantee very high quality (Grade D), they can guarantee a higher quality than Grade A.

• Storage: In general, storage operators expect significant additional impurities from storage, while the level ofcontamination varies depending on the location, technology used and previous utilisation of the storage. Purification to Grade A is considered feasible by storage operators. But qualities beyond this require considerable additional technical effort and can pose financial risks for projects that are already in an advanced development stage (and have expected low quality standards. Challenges of storages to achieve high hydrogen quality standards pose the bottleneck for high quality standards in the hydrogen system.

Next steps

The study shows the importance of the discussion of hydrogen quality, which should be further researched. The optimal quality is one that minimises the overall economic implications - for example with regard to costs and speed of hydrogen roll-out.

In order to establish this optimal quality for the overall system, the focus should be placed on analysing threshold values for individual impurities (of certain substances such as hydrocarbons or nitrogen) and discussions about existing quality levels (grades A and D). In particular storage operators need to further research to what extent and at which cost they can achieve higher quality standards than required for Grade A. At the same time, the specific quality requirements of various hydrogen users require further analysis. And finally, the national discussion need to be aligned with the discussion at European level.

Click here to read the full report (in German).