Buses are an essential part of the public transport that needs to be decarbonized. The special requirements due to route planning, low idle times and high mileage mean that the implementation of battery-electric drivetrains cannot be implemented in all cases. Especially in rural or mountainous regions, fuel cell buses can stand out with their performance and long range. But fuel cell buses also offer an advantage in winter when the passenger compartment needs additional heating. Here, the waste heat from the fuel cell can be harnessed. Because of this high potential, research and development projects are looking at future solutions.