Under the agreement, Orlen will supply 360kg of hydrogen per day to fuel 18 Solaris buses, with the option to expand to 27 vehicles. Deliveries are expected to begin next year when the buses are rolled out.

Up to 400,000kg of hydrogen will be delivered over the PLN 24.1m ($6.7m) contract, but that could increase to 550,000kg if the option for extra vehicles is actioned.

A hydrogen refuelling station on Łukasiewicza Street will provide the fuel for KM Płock buses and individual vehicles.

The transport authority has previously deployed 12 and 18-metre hydrogen buses in the Polish city and tested them on various routes to analyse capabilities.

Poland has been active in deploying low-emission public transport operations, with hydrogen buses manufactured by Solaris and in operation across the country.

However, the sector has faced setbacks. Transport operator MPK Poznan withdrew all Solaris Urbino 12 buses from service last March, just weeks after finalising a contract for nine additional units.

Reportedly, the decision was made as an emergency measure after onboard diagnostic systems in some of the vehicles detected unexpected malfunctions.

Additionally, Polenergia scrapped its plans to supply hydrogen for Rzeszów’s city buses in Poland at the start of the year, citing legal uncertainties as the primary reason.