The European research project MetHyTrucks has developed four reference sampling systems for hydrogen at filling stations for heavy-duty vehicles and tested them under controlled conditions. The results are intended to advance the standardization of hydrogen quality assurance in heavy-duty transport (Heavy-Duty, HD). Samples were taken at dispensers with both 350 bar (H35) and 700 bar (H70). According to the project, there was previously a lack of technical evidence to develop reliable guidelines for sampling. The project ends in May 2026 and is in the final phase of drafting its guidelines, according to the press release.
Three devices tested for gaseous samples
Three of the sampling devices from different manufacturers address gaseous components. They were tested at the ZBT station in Duisburg.
- The device from Engie was adapted for 350- and 700-bar stations with a tank capacity of 55 liters and operates between −40 °C and +80 °C.
- The HySaM device, originally developed for 70 MPa stations, received a new 350-bar line and operates with flow rates of up to 120 g/s in three system modules.
- The NPL-DirSAM device operates according to the ASTM-D7606-17 strategy for direct sampling and requires the filling station to be in maintenance mode. It is designed for 10-liter sample cylinders and also supports flow rates up to 120 g/s.
For sampling to investigate particles, the consortium chose an alternative truck filling station where quantifiable particle amounts in the dispensed fuel had already been documented. H35 and H70 dispensers were available there. According to the consortium, all systems met the requirements of the heavy-duty refueling protocols.
Guidelines for safety and sampling at hydrogen filling stations in progress
In parallel, the consortium is working on several good practice guidelines. A central topic is the safe venting of hydrogen during sampling—a challenge due to high flow rates and the need to minimize station downtime. The corresponding guideline is to be aligned with ISO standard 19880-9.
Two additional guidelines will address filling station parameters for representative and reliable sampling. The influence of temperature, pressure, venting procedures, and storage bank on the composition of hydrogen samples is being investigated. A derived guideline is to propose a harmonized set of filling station parameters that improves the comparability of samples from different direct sampling strategies. This includes information on minimum sample size, filling pressure, and uncertainty assessment with a relative target value of 10 percent.
Findings to be incorporated into ISO and EN standards
The project results are to be directly incorporated into the work of the ISO TC 197 standards committee, particularly into ISO standard 19880-9. There are also intersections with standards EN 17124, EN 17127, ISO 19880-8, ISO 19880-1, and ISO 14687, which regulate requirements for hydrogen quality as well as technical and safety conditions for supply and refueling.
MetHyTrucks runs over three years from June 2023 to May 2026 and has a budget of 909,000 euros. The project is funded by the European Partnership on Metrology, co-financed by the EU's Horizon Europe program and the participating states. The consortium includes ten organizations from eight countries, coordinated by the Swedish research institute RISE. Participants include, among others, the Physikalisch-Technische Bundesanstalt (PTB), the Center for Fuel Cell Technology (ZBT), Engie, SINTEF, and the British National Physical Laboratory (NPL).
