Barcelona, 19 September, 2025 – Barcelona has unveiled its first diesel bus converted into a zero-emission hydrogen vehicle, a pioneering project made possible through innovation funding from EIT Urban Mobility, an initiative of the European Institute of Innovation and Technology (EIT), a body of the European Union.
The project, known as HERO – Hydrogen Retrofit, received €460,000 from EIT Urban Mobility’s 2024 innovation call. The funding enabled Transports Metropolitans de Barcelona (TMB), in collaboration with Catalan company EVARM and German fuel cell manufacturer EKPO, to convert a conventional diesel minibus into a clean vehicle powered by a hydrogen fuel cell.
Unlike traditional electric buses that rely on large batteries requiring overnight charging, the retrofitted vehicle operates with a smaller 35 kWh battery continuously recharged by a 120 kW fuel cell. The system generates electricity onboard by combining hydrogen with oxygen from the air, emitting only water vapour.
Since March 2025, the minibus has undergone pilot tests to validate efficiency and performance. It will now begin circulating without passengers on select routes in Barcelona, becoming the first hydrogen retrofit vehicle of its kind to operate on the city’s streets.
At the same time, TMB has also presented a separate prototype hydrogen-powered minibus developed in Sant Boi de Llobregat (Barcelona). This vehicle, designed to be incorporated into TMB’s fleet in the future, reinforces the company’s roadmap toward full decarbonisation of public transport.
TMB CEO Xavier Flores described the initiatives as “a step forward in finding solutions that allow all vehicles to become zero emissions,” stressing that they exemplify the innovation TMB is committed to fostering.
By supporting HERO – Hydrogen Retrofit, EIT Urban Mobility has played a key role in accelerating the transition to sustainable urban transport and paving the way for the broader adoption of hydrogen retrofits for vans, trucks, and minibuses across Europe.
[picture above: Mr Xavier Ribas, CEO EVARM: ; Ms Lluïsa Moret, Major of Sant Boi de Llobregat and president of the provincial deputation of Barcelona; Mr Xavier Flores, CEO TMB; Mr Tomás Mejía, OPTIMA and Mr Martí Massot, Head of Innovation Hub South at EIT Urban Mobility]
