The dense network of routes operated by PostAuto around Brugg is suited to the test in terms of both topography and routing, with a mixture of city traffic, country roads and village streets. The routes will be operated by the PostAuto company Voegtlin-Meyer AG, which will also service and refuel the five fuel-cell post vehicles at its garage location.

Aargau Canton is supporting the fuel-cell bus project with a subsidy of 1.5 million Swiss francs (US$1.6 million) from the Swisslos lottery fund. PostAuto expects to save some 2,000 tonnes of CO₂ during the five-year test phase.

Compared with the fuel-cell omnibuses that were tested from 2003 on as part of the CUTE and HyFLEET:CUTE projects, the new Citaro FuelCELL Hybrid offers a number of innovations: hybridization with energy recovery and storage in lithium-ion batteries; powerful electric motors fitted in the wheel hubs with a continuous output of 120 kW; electrified PTO units and more advanced fuel cells.

These cells will have an extended service life of at least five years, or 12,000 operating hours. The fuel-cell stacks in the new Citaro FuelCELL Hybrid are identical to those used in the Mercedes-Benz B-Class FCELL with fuel-cell drive.

As in the earlier fuel-cell buses, the two stacks are installed on the vehicle’s roof. A new addition is lithium-ion batteries, which store energy that is recovered during braking. With the electric power from this pack, the new Citaro FuelCELL Hybrid is able to run for a number of kilometers on battery power alone. The concept behind the new FuelCELL bus essentially corresponds to that of the Mercedes-Benz BlueTec hybrid buses. However, these derive their electric power from a diesel generator, whereas in the new FuelCELL buses the fuel cells generate the electricity for the drive motors.

The improved fuel-cell components and the hybridization with lithium-ion batteries result in a reduction in hydrogen consumption of almost 50% for the new Citaro FuelCELL Hybrid compared with the previous generation. As a result, it has been possible to reduce the number of tanks from the total of nine on board the fuel-cell buses deployed in earlier trials to seven on the current vehicles, holding 35 kg of hydrogen in all. The operating range of the fuel-cell bus is more than 250 kilometers (155 miles).

The EU-funded CHIC (Clean Hydrogen in European Cities) project will permit the integration of 26 fuel-cell buses into daily regular services in five European cities.

The project is based on a gradual introduction of hydrogen-powered fuel-cell buses, and aims to set up bus fleets with fuel-cell vehicles, along with the necessary infrastructure. With the CHIC project, Daimler Buses is following up on two previous successful projects, CUTE and HyFLEET:CUTE, launched by the European Union, which ran from 2003 to 2009. A total of 36 Mercedes-Benz Citaros with second-generation fuel-cell drives have already proven their worth at twelve transport operators on three continents, with more than 140,000 operating hours and a total distance travelled of over 2.2 million kilometers (1.4 million miles).