Volkswagen Magazine

THINK AHEAD

the coal of the future.

Some years ago, there was a great deal of talk about fuel cells as the successor to the combustion engine. Then things grew quiet. Now fuel cells are enjoying a comeback, and they’re well on the way to a breakthrough.

Text Marc Lüttgemann
Infographic C3 Visual Lab

In Jules Verne’s 1874 novel “The Mysterious Island”, a group of castaways land on a deserted Pacific island. The stranded characters pass the time in long discussions and arguments about the future, and one day they come to the subject of what could replace the finite material of coal as a fuel. In the process Cyrus Smith, a worldly engineer and the brains of the group, makes a bold prediction.

“Water”, he says, before continuing, unperturbed by the incredulous reactions of his companions, “water decomposed into its basic elements... decomposed doubtless by electricity which will by then have become a powerful and manageable force.... Yes, my friends, I believe that water will one day be employed as a fuel, that hydrogen and oxygen, which compose it... will furnish an inexhaustible source of heat and light.... Water”, concludes Cyrus Smith, “is the coal of the future.”

Cyrus Smith and his fellow castaways in their granite house in Jules Verne’s “The Mysterious Island”.

“Yeah, there’s something to that”, says Thomas Lieber when asked about Cyrus Smith’s 140-year-old idea. Lieber is the head of Electro-Traction at Volkswagen and is thus responsible for the development of hydrogen-powered vehicles. What sounds fantastical in Verne’s tale is perfectly logical to him as an engineer. After all, the hydrogen in water is a very good energy carrier, which is why aerospace engineers have long used it to generate energy in spacecraft. It is also used as a fuel in submarines.
“Yeah, there’s something to that”, says Thomas Lieber when asked about Cyrus Smith’s 140-year-old idea. Lieber is the head of Electro-Traction at Volkswagen and is thus responsible for the development of hydrogen-powered vehicles. What sounds fantastical in Verne’s tale is perfectly logical to him as an engineer. After all, the hydrogen in water is a very good energy carrier, which is why aerospace engineers have long used it to generate energy in spacecraft. It is also used as a fuel in submarines.

This is how a fuel cell works

This is how a fuel cell works in 1838 by the chemist Christian Friedrich Schönbein. Sir William Robert Grove read of Schönbein’s research and developed the principle further in 1839. Today the two are regarded as the fathers of the fuel cell.

In a modern car fuel cell, hydrogen and oxygen meet at an electrolyte membrane and react to form water. The energy released in this reaction is sufficient to power an electric motor.

Volkswagen has been working on fuel cells since 1996. Initial prototypes were based on the Bora (2000 and 2001), the Touran (2004) and the Tiguan (2008). Most recently, Volkswagen presented the Passat HyMotion and Golf Estate HyMotion concept studies at the Los Angeles Auto Show 2014. On the outside, the cars were very similar to the series versions, distinguishable only by the modified radiator grilles with enlarged air intakes.

The reason for the change: since the entire waste heat of the fuel cell is dissipated exclusively through the cooling water, the radiator surfaces have to be enlarged. On the inside, four hydrogen tanks replace the petrol or diesel tanks, and in the engine compartment up front a fuel cell stack and electric motor replace the combustion engine. Test drivers were impressed by the HyMotion models’ day-to-day usability: they put out 100 kW of power, go from 0 to 62 mph in ten seconds and can be fuelled up for a range of up to 310 miles in five minutes.

The fuel cell in the Golf Variant HyMotion

Fuel cells can also be installed in Volkswagen vehicles using the Modular Transverse Matrix system.

1 The engine compartment houses a fuel cell stack including an electric motor.

2 Hydrogen is transported in pipes from the tanks to the fuel cell stack.

3 The rear of the vehicle houses four tanks that store gaseous hydrogen at a pressure of 700 bar.

Signs of a comeback are emerging

But if hydrogen is such a good energy carrier, and fuel cells enable CO2-free driving, and test vehicles make such a good impression on test drivers, why are there scarcely any hydrogen-powered vehicles on the road? Among the key reasons are many unanswered questions regarding the hydrogen infrastructure and about generating hydrogen with renewable energy sources. There are signs, however, that fuel cells will reach the mass market in coming years and expand the drive technology mix for cars. One important factor is that after years of divergent technologies, the industry has now agreed on many standards: these call for gaseous hydrogen rather than the liquid form, compression of the hydrogen gas in the tanks to 700 bar, and uniform filler necks. The result, explains Lieber, is that “drivers of hydrogen-powered vehicles can use all filling stations worldwide.” Promising things are afoot with regard to infrastructure as well. In Japan, the hydrogen filling station network is growing fast thanks to public subsidies, likewise in California; in Europe, the same is set to occur soon in certain countries. In Germany, a consortium of numerous companies from the automotive and oil industries known as H2 Mobility has agreed on a plan of action which aims to have some 400 hydrogen filling stations in operation throughout the country by 2023. In the context of a range of several hundred kilometres, that could be enough to convince drivers of the day-to-day usability of hydrogen-powered vehicles. As Lieber comments: “The successful expansion of the infrastructure is primarily a question of the political arena creating a reliable framework and providing the means to make it a reality.” The prices for fuel cell-powered cars will also drop in the years to come – as was observed in the past with both electric cars and plug-in hybrids as well.

The history of fuel cells at Volkswagen.

It will still take some time, but Thomas Lieber is convinced that fuel cells in series vehicles are truly on the way. Will fuel cells replace combustion engines, natural gas vehicles or plug-in hybrids? “No,” he says, “the reality will be more that we will see multiple drive technologies in parallel, because each one has its advantages.” And when will that day come? When will hydrogen replace fossil fuels in series vehicles from Volkswagen, as Cyrus Smith prophesied in Jules Verne’s novel? “2020 to 2025 is a realistic timeframe,” says Lieber.
The future is not far off.