To celebrate 125 years since the company's founder invented the motor car, Mercedes-Benz is taking three hydrogen fuel cell B-Class hatchbacks around the world to prove that the technology's ready — and that all we need now is the refuelling infrastructure.
If it wasn't for its lime green paintwork and prominent livery, this car would look like a normal, run-of-the-mill B-Class hatchback.
The B-Class F-Cell is an electric car, but one with a difference. There's a lithium ion battery pack under the boot floor, but its primary purpose is to store energy captured from regenerative braking. The main source of energy for the electric motor is a fuel cell stack that generates electricity by combining hydrogen stored in the car's tanks with oxygen drawn in from the atmosphere to produce water.
Starting up the F-Cell results in complete silence. It's not until you prod the gas pedal that you can hear the whirr of the electric motor. With a single reduction gear there's none of the usual surging sensation as you move up through the gears, just a constant accumulation of speed and a rise in volume from the motor.
Even at its most vocal it's noticeably quieter than a diesel or petrol engine. With the cabin's general air of silence, tyre and wind noise were far more noticeable.
The electric motor produces 100kW of power and 290Nm of torque. While Mercedes-Benz says that the performance is comparable to a B-Class fitted with a 2-litre petrol engine, we found off-the-line acceleration to be a bit on the slow side. However, there's plenty of torque for impromptu overtaking.
Handling seems comparable to a normal B-Class, although the 8km city route we drove didn't really lend itself to enthusiastic driving — that and the fact that the we were a bit cautious driving an expensive left-hand-drive vehicle.
The interior is pretty much bog-standard B-Class — that is, comfortable and classy — but not exactly bursting with excitement.
The B-Class features a "sandwich floor" underneath the passenger cabin, which in the F-Cell houses much of the fuel cell kit. Passenger capacity and comfort is unchanged from an internal combustion-engined B-Class.
The F-Cell's boot holds pretty much the same amount of kit as a petrol or diesel B-Class.
Under the floor, though, the spare tyre has made way for a lithium ion battery pack.
The pump for refilling the car's hydrogen tanks has been designed to resemble the look and feel, as well as having the same method operation, as a traditional petrol or diesel pump.
Hydrogen filling-stations are scarce; but there are only about 200 such stations worldwide and they're concentrated in certain places, like Germany, California and Detroit. As such, the F-Cell vehicles currently in Australia need to be trailed by these two refuelling trucks. The big red tanks on the semi-trailer can hold a total of about 480kg of hydrogen.
When the F-Cells need to be refuelled, the hydrogen tanks on the semi-trailer are hooked up to a compressor in the black van. The compressed hydrogen is then transferred into the cars' tanks via the pump we saw a few pictures ago.
Filling up the car's tanks via this method takes roughly 20 minutes, a fair bit longer than the three minutes required when using a forecourt pump. Either way it's considerably quicker than the eight hour charge times quoted for most battery electric vehicles.
The shiny black ring around the pump's nozzle hides infrared communications equipment that allows the pump to talk to the car and find out about its tank pressure, tempature, fill level and the like.
The B-Class' tanks hold 4kg of hydrogen at 70 megapascals or about 690 times atmospheric pressure at sea level. With the tanks full, the car's range is claimed to be 385km.
To prevent any nasty sparks from occurring, the black van needs to be connected to an earthing point on the B-Class. Thankfully an earthing cable isn't required when using forecourt pumps.
Until the F-Cell is kicked into life, the only hint that you're not driving a regular diesel or petrol B-Class is the instrument cluster, which features a power meter in lieu of the tachometer. Step on the gas and it'll show you how much power the electric motor is sending to the front wheels. Hit the brakes and you'll see how much energy is being recaptured via regenerative braking.
For the F-Cell world drive, each vehicle is fitted out with two GPS units. The yellow Tripy II unit on the right has the itinerary and course notes for the days when they're travelling along the official drive route. The TomTom Go unit on the left is fitted out with worldwide maps so the fleet can find their way around strange new towns for photography, press events and cold beers.
Excluding press and off days, the three F-Cells will cover 30,000km in the first circumnavigation of the world in fuel cell vehicles.
For the world tour, Mercedes-Benz has fitted a pair of high-frequency emitters in the grille to scare away wildlife — a real hazard on country highways from dusk until dawn.
A GPS receiver is fitted discreetly to the roof.
This little box allows engineers back in the company's Stuttgart headquarters to track the F-Cells' progress and condition during their worldwide jaunt.
Along with the three B-Class hatchbacks, a small army of GL-Class four-wheel drives and Mercedes vans are also making the trek.
As well as carrying spares and logistics equipment, the support vehicles carry all the necessary gear to document the journey.
According to Mercedes' hydrogen fuel partner Linde and its Australian subsidiary BOC, the technology that's currently being utilised to produce hydrogen is quite mature, and all that's required for mass production of fuel cell cars to begin is big business and government getting together to collaborate on rolling out refuelling infrastructure.
While the only emissions from the B-Class F-Cell's tailpipe is water, the steam methane reformation process that's presently used to produce most of the world's commercial hydrogen emits plenty of greenhouse gases. According to BOC, though, the well-to-wheel greenhouse footprint for hydrogen is about 30 per lower than that of diesel fuel.
Future sources for hydrogen fuel may come from algae farms or be produced with green sources of energy, such as wind and solar.
The world tour began on 30 January 2011, and will take a scheduled 125 days to complete while traversing 14 countries across four continents.
The trek begins and ends at the company's headquarters in Stuttgart.
Before arriving in Sydney for the Australian leg, the F-Cells went from Stuttgart to Lisbon via Paris, then on to Vancouver via Miami, San Antonio and Los Angeles.
In Australia the routes takes the F-Cells from the Sydney to Perth along the coast via Melbourne and Adelaide.
For the final leg of the trip, the F-Cells will be shipped across to Shanghai, from whence they'll drive back to Stuttgart via Beijing, Xian, Moscow and Oslo.
By 2012, Mercedes-Benz will have produced 200 commercially available units of the current generation B-Class F-Cell. You can't just rock up to a Mercedes-Benz dealer and buy one though; the cars are only for lease, and only to selected individuals, companies and government departments.
Mercedes-Benz is working towards having F-Cell vehicles available for sale by 2015, although only left-hand drive models have been confirmed thus far.