It makes almost no sound, just a gentle whistling noise, plus it’s very easy to drive and had its own accompanying team of experts from GM – so even the flat stretch across Denmark was okay. After about 180 kilometres we stopped for refuelling. I was surprised how little time that took; four minutes – and we hit the road again. It was noticeable that the nearer we came to the German border, the more interest we aroused. Especially in Hamburg, where even stern-looking policemen smiled at us.

The fuel consumption was a surprise to me: our top speed in Germany was 160 km/h. Yet we did not use much more hydrogen than in Denmark, where we kept the speed to 110 km/h.

By Vítìzslav Kodym (CZ) Every leg of the fuel cell marathon starts at the Technical University of the particular town. In Copenhagen the Danish transport minister came to watch. He was also very happy to be able to drive a few hundred metres himself. But then it was our turn. A development engineer from Opel joined the Auto Tip reporter in the car, our little convoy included the Vivaro service car and a Frontera, in case we needed towing. Neither of the vehicles had to be called upon.

A conventional key starts the engine but there then follows a "check-up" phase which takes 30 seconds. Then the appropriate button has to be pressed to select the desired "speed range". The vehicle accelerates gently and responsively. It feels quite strange, since the driver has no acoustic feedback from the electro-engine, which runs without any noise. All you hear inside the car is the purring of the ventilator fans, which is enough to disguise the usual tyre sound. Generally speaking, the car accelerates quickly and mostly in a linear manner. There is no stress when deciding whether to overtake, although at first the knowledge that we were driving one of the most expensive cars in Europe did rather cramp our style. We test the flexible acceleration on the motorway and have absolutely no problems among the disciplined Danish drivers. The fact that the car is heavier in the front does affect the steering a bit, the Zafira is stiffer when cornering, but these are matters which could be changed by adjusting the suspension or the steering, which are both the same as on standard models.

Our first stop to refuel with hydrogen is after 175 kilometres. A mobile fuel unit is waiting at the motorway service station; the crew ticks off a number of safety checks one after the other. Strict rules have to be observed when refuelling; apart from the fact that it is inflammable, hydrogen does not liquefy until cooled to -253°C, so that is obviously the temperature of the liquid flowing into our tank it takes about 4 minutes to pump the tank full, during which time a little white cloud of vapour hovers over the scene. A new type of tank for liquid hydrogen is mounted above the Zafira's rear axle, so we do not fill it to the limit, but enough to take us about 200 km.

Hamburg to Delft
By Margret Hucko 

As the Opel Zafira pulls out of the foyer at Hamburg university it leaves a long trail behind it. Water is dripping out of the exhaust pipe. Not a great deal. About as much as would go in a shot glass.

Bob Lutz, boss of GM Europe, who is cautiously manouevering the hydrogen Zafira out of the glass hall, does not notice a university employee wiping up the puddles left by the prototype. Because there is a big blue card stuck on the rear screen of the HydroGen3. The map shows our route from Hammerfest to Lisbon.

Today the Zafira is driving 520 kilometres from Hamburg to Amsterdam. Bob Lutz parks the HydroGen3 in front of the university before handing me the ignition key. This American manager loves sports cars. He loves speed and he loves jet fighters. But what about this eco-car, this Zafira with the cleanest engine in the world? With its modest 82 bhp? That isn’t quite in the same league. Not really.

"I like the sound of the engine. The whistling reminds me of a jet engine," says 72-year-old Bob Lutz. The GM manager likes to trust his gut instincts. "My strong point", as he asserted in an interview. This time his gut feeling is that hydrogen is the fuel of the future. "There is no alternative." He also thinks that hybrids have great promise, in other words cars with two types of engine; one electric and one conventional combustion engine. But his gut feeling is also that there will be more demand for these cars in America than in Europe.

Wonder what that guy in the tuned Vectra thinks about the car of the future? On the A1 highway to Bremen an Opel with a "bye-bye" sticker overtakes us. The crew-cut driver gawps at us as if we were moving backwards. What’s he thinking right now? Perhaps: "Do they do tuning on hydrogen cars?" Of course not. Not yet. Although the HydroGen3 has brakes from the OPC range, the nimble, sporty Opel models. And this Zafira has pretty taut suspension. But couldn’t the engine do with a bit more zing? Perhaps, with the next generation of hydrogen cars, a buffer battery will give some added power when the driver asks for it.

We are happy with the car’s performance on the stage ending in the Netherlands. Three refuelling stops, no breakdowns. Just once, negotiating a Dutch roundabout, the red warning light came on. But HydroGen3 started up again without the GM team having to do anything. So far, the engine of the future would seem to be "Opel the reliable."