PostAuto Schweiz AG has become the first company in Switzerland to deploy
fuel-cell technology for public road transport.
Since the end of 2011, five Mercedes-Benz Citaro FuelCELL Hybrid models have
been serving on routes in and around Brugg (in the canton of Aargau) as PostAuto
vehicles. Over the next five years, PostAuto will test the new generation
fuel-cell drive, using clean hydrogen as fuel.
The dense network of routes operated by PostAuto around Brugg is ideally
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 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
significant innovations: hybridisation with energy recovery and storage in
lithium-ion batteries, powerful electric motors fitted in the wheel hubs with a
continuous output of 120 kilowatt, electrified PTO units and more advanced fuel
cells.
These cells will have a 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 already 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 energy accumulator, the new
Citaro FuelCELL Hybrid is able to run for a number of kilometres 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, without producing any emissions
whatsoever.
The improved fuel-cell components and the hybridisation with lithium-ion
batteries result in a reduction in hydrogen consumption of almost 50 percent 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 now over 150 miles.
With these diverse technical advances, buses running on electric power alone
with fuel cells as energy generators are now a major step closer to production
maturity.
