The title of this post refers to the most recent purchase by TPER, the public transport provider in Bologna, Italy. The number is huge: in the first half of 2025 (latest data available) in the whole EU became operational 279 hydrogen buses, that would project to ~570 buses in the whole year; This means 25% of the hydrogen buses produced in Europe are for Bologna public transport. These numbers unfold the magnitude of the risk TPER has decided to embrace, together with the increasing numbers of similar projects that get cancelled across the continent (Brusseles, London, Poznan, ...) due to high hydrogen cost and the existence of electric-battery alternatives that are becoming more competitive.

Energy efficiency

Hydrogen fuel efficiency in the automotive sector has a theoretical limit that cannot be overcome. If you consider green hydrogen, which is produced from water electrolysis using electricity, you obtain that just 25% of the initial electricity will be available at the wheel of the bus, a much smaller number if you compare it with the battery-electric alternative, which makes available ~75% of the initial energy, as summarized by MAN's CEO a few years ago. The traditional alternative is producing hydrogen through Steam Methane Reforming (SMR) which is slightly more efficient, but most of this gain gets lost once coupled with carbon capture technology, required for reducing CO2 emissions for this process which involves methane.

Bologna scenario

From a pilot project, TPER was able to cover 14-15 km/kg of H2, slightly higher than what was experienced by other local transport providers, that leads to a fuel cost of ~1€/km and remains much higher than the cost of battery-electric buses whose running cost is almost half of that, as found in the Bolzano case.

Why Hydrogen?

It's difficult to see the reason behind this investment. Even if a part of the intial investment is covered by European funds, the operative cost is two times higher than running battery electric buses. The only consolation is that TPER runs ~1700 buses in Bologna area (2023 data, the number should decrease in the coming years due to the tram) and hydrogen buses will be slightly less than 10% of total buses, so the impact is still relatively limited. I reccomend TPER executives and Bologna administration to have a look at Micheal Liebreich's Hydrogen Ladder, hoping that they won't fall into the tentation to experiment with hydrogen in sectors like domestic heating, as attempted in Modena.

With the information publicly available, hydrogen buses are still the costlier option. Investments should allow the lowest operational cost possible. Otherwise, it is no wonder you need to increase ticket fares by 53%.