There's been yet another incident involving hydrogen-fueled public buses, this time in Poznan, Poland.
According to Hydrogen Insight, 14 out of 25 hydrogen fuel cell (FCEV) buses in the city's fleet simultaneously failed earlier this week, forcing bus manufacturer Solaris to pull the entire fleet from service. They've since been temporarily replaced by the city's older diesel buses.
Solaris is Europe's top supplier of hydrogen-powered buses and, until now, has achieved a near-perfect reliability record.
Poznan initially deployed two FCEV buses - part of a larger 25-unit order - back in October 2022 and experienced zero issues until just a few days ago. Reportedly, the affected buses' onboard computers each signaled a failure at once, and the issue is now being investigated by both Solaris and the hydrogen fuel supplier.
A Solaris spokesperson, per Hydrogen Insight, had this to say:
"It is most likely that the symptoms and timing of the malfunction are related to the quality of the hydrogen. As you may know, the hydrogen supplied to vehicles must meet specific purity standards set by regulations, which is 99.97% purity. If the hydrogen does not meet these parameters, it affects the operation of the fuel cell. Samples of hydrogen from the station supplying MPK Poznan have been taken and will be analyzed. Based on this analysis, we will be able to determine the cause of the system's improper operation."
Each of the 25 buses in question are refueled at a dedicated hydrogen station in the city, which is operated by Polish oil refiner Orlen. Orlen also supplies the hydrogen fuel.
"Currently, together with the bus manufacturer and the hydrogen fuel supplier, we are working on explaining the cause and solving the problems, about which we will inform you on an ongoing basis," the city wrote on its Facebook page.
Since 2012, Solaris has registered 425 hydrogen buses in Europe. This translates to a 22.5% market share in the continent. Chances are, this is an isolated incident due to a bad hydrogen fuel mix.
Hydrogen fuel can only have a maximum of 0.03% of other gas types mixed in, which apparently hasn't caused problems until now. Still, knowing that hydrogen fuel suppliers have very little room for error in this regard is unsettling.
Fortunately, this latest hydrogen-powered public bus issue isn't quite as serious as an incident in South Korea where a Hyundai-built public bus exploded while parked at a depot, lightly wounding three. The incident occurred after charging session and the vehicle's rear-end was blown off.
[Related: Hydrogen-powered bus explosion raises safety concerns]
The future of hydrogen as a fuel for vehicles remains in question not just because of these bus issues but also due to high fuel costs and a lack of charging infrastructure.
Last month, hydrogen fuel cell Class 8 semi manufacturer Nikola Motors filed for Chapter 11 bankruptcy protection. The OEM, coincidentally, issued a recall for almost 100 units of its Tre FCEV semi over hydrogen tank mounting concerns, potentially causing leaks.
[Related: Bankrupt Nikola recalls 95 trucks over hydrogen tank safety issue]
Although the recall's timing had nothing to do with Nikola's financial problems, the concerning issues surrounding hydrogen as a fuel still remain.
