Certifiably Complicated

One thing that became apparent at the IAA Commercial Vehicles 2018 was that the issue of hydrogen tank approval had yet to be resolved. Though it had already been said years ago that tanks “must only get approved,” the process is taking much longer than expected. At present, there are few 700-bar type IV units for sale in Germany.

The key reason for the lack of products seems to be that European automakers have not made a firm commitment to purchase tanks in large quantities for their vehicles. So far, OEMs have been ordering only few units for testing or integration into prototypes. At the same time, they have been demanding a lot from the manufacturers of those tanks, for example, by restricting the space in which units could be installed.

 Tank manufacturers in Europe are deeply frustrated about the entire situation. Circumstances will not permit them to ramp up production capacity and make their business economically viable, so they are waiting to get products approved until companies start asking for more.
The outlook is a bit of a different for those manufacturing tanks for a pressure of 350 bars or 500 bars. Type IV units in that pressure range are available for sale. The needed tank volume is a bit higher than that for 700-bar ones, as the lower pressure level reduces energy density. However, 350-bar tanks, for example, are mainly used in commercial and railroad vehicles, which offer more space to install a unit. And 500-bar tanks are typically found in stationary systems, which is why they are produced in higher numbers, so that unit prices have fallen as well. Sometimes, more than a hundred of them make up a single system, which is sold as a containerized solution. For instance, in Meckenheim, Cologne’s mass transit company is planning to install a fueling station that includes a stationary container housing 162 individual 500-bar pressure cylinders with a total weight of 1 metric ton.

In Asia, the above-mentioned issues have already been dealt with. Toyota has built tank factories and uses 700-bar units in its Sora buses. Hyundai has partnered with a manufacturer that can rely on Nexo car sales to drive demand. By contrast, reports say Daimler will need barely more than 1,000 units for the time being and after a few fuel cell vehicles leave the factory, production will again be put on hold.
As for the tank manufacturers, they said that those many delays in bringing fuel cell cars to market in Germany had nothing to do with their products. The bottleneck was not the tank: Approval could be obtained in around 12 months.

Duisburg’s ZBT research institute, however, has determined that there is still some more work to do when it comes to hydrogen tank regulations. In partnership with the National Organization Hydrogen and Fuel Cell Technology, or NOW for short, and Germany’s Materials Research and Testing Institute, BAM, it will hold a workshop in Berlin for tank manufacturers from all corners of the country to figure out whether there really is a need for all those efforts to remove a pressure vessel from a system and test it for leaks by filling the tank with water.


Not without reason did the German transportation ministry launch a project called Delfin right before year’s end. Its aim is to develop a pressure vessel at a reduced cost and weight. The ministry said that it would provide around EUR 7.5 million to “clear away one of the main barriers to market growth.” It is worth noting that the list of project partners includes not only automaker BMW, Daimler subsidiary NuCellSys and supplier Nproxx but also Ford. It has been a long time since the corporation announced anything fuel cell-related.

It seems there are still some points to clear up.