Emitting nothing more offensive than water, the mass-produced hydrogen-powered car remains the elusive dream of zero-emissions motoring. But unlike many other elusive dreams, it is not waiting for some missing technological link to steer it off the drawing board and onto the road, rather a concerted act of will by the government, the auto industry, and — perhaps most problematically — the oil business.
Indeed, in the unlikely event that these disparate groups wake up one morning and decide that all new cars will be run on hydrogen, Markus Bachmeier, head of hydrogen solutions at Linde, believes the technology is now mature enough to make this dream come true. He said: ‘We have already met a lot of challenges — we’ve built more than 70 stations worldwide and completed more than 120,000 refuellings into cars in 15 countries. Although it is not yet widespread, in my eyes it really is a proven technology.’
Perhaps the best example of this maturity is the actual vehicles. Refuelled in less than three minutes and capable of up to 550km on a full tank, today’s most advanced hydrogen prototypes — cars such as the Honda FCX Clarity — are easily a match for most production vehicles, Bachmeier claimed. ‘We have seen tremendous progress in the last five to 10 years in terms of vehicle quality and the maturity of the technological concepts. When you drive these cars you can no longer tell that they are prototypes; in technical terms they are pre-production or production quality.’
Unsurprisingly, he also believes the technology has significant advantages over the battery-powered vehicles that have so far enjoyed greater commercial success. ‘As well as the driving range, which is anywhere between 400-550km, an advantage of hydrogen-powered cars is that you get full performance until the last drop of hydrogen in the tank, unlike batteries, which decrease in performance during the last hour.’ At the other end of the hydrogen supply chain, courtesy of Linde’s decades of experience providing the gas to a range of industries, the science and process of hydrogen production is also extremely well understood.
Linde is looking at a number of different processes. The most widespread of these is steam reforming. Used for decades and ideally suited to large-scale production, this typically reacts methane with steam to yield carbon monoxide and hydrogen.
Although it is not the cleanest process, Bachmeier claimed that hydrogen produced this way could still lead to a 20 per cent CO2 reduction over good diesel combustion engines. He added that research into the use of biogas in steam reforming could lead to even greater reductions.
Another promising avenue is the use of electrolysis-based production methods, which could, Bachmeier said, make use of renewably generated electricity to bring about 90 per cent CO2 reductions over diesel. He added that he could envisage electrolysis plants being hooked up to nuclear power stations, ‘providing the nuclear plants are safe’.
Although tongue-in-cheek, this comment was perhaps an implicit nod to the fact that some still view hydrogen as a hazardous substance — an ill-founded fear, according to Bachmeier. ‘People remember explosive hydrogen from their school days — but when you look at it from a technological perspective, yes, there is a lot of energy in hydrogen and that is why it is so valuable,’ he said. ‘We have hydrogen refuelling stations in city centres. We take every measure to ensure it is safe and we haven’t had any major accidents in our company since we started that. After millions of kilometres driven, there hasn’t been a single hydrogen-related accident.’
Just as a number of production processes will vie for dominance in the hydrogen economy, so will competing hydrogen fuelling methods, and the jury is out on whether liquid hydrogen or gaseous hydrogen will prevail.
Both have significant technical demands. Liquid hydrogen requires sophisticated cryogenic technology to maintain hydrogen at 20 Kelvin, while gaseous hydrogen pressurised at 700 bar calls for an ultra-safe system from compression to the tank of the car. Bachmeier would not be drawn on which approach he thinks will win out. ‘It’s not for us to decide which of these refuelling technologies is better,’ he said. ‘It will be a decision by the market and the customers.’
With many of the major technology hurdles overcome, Bachmeier returns to the Catch-22 that is holding the hydrogen economy back: with few refuelling stations, manufacturers are not prepared to take the plunge on larger production runs. But with few hydrogen vehicles on the road, there is little demand to justify the development of thousands of hydrogen refuelling stations. So how is the industry going to flourish in the way that its many advocates believe it will?
Bachmeier said: ‘The technology side we can manage. It’s getting more cars on the road and more stations on the roadside in synch that is the challenge.’
He believes that public transport and fleet vehicles, which all return to a central depot for refuelling, will have a big role to play in stimulating the hydrogen economy. But taking hydrogen motoring to the next level will require an unprecedented level of cross-industry collaboration. ‘We can only do this with partners in the auto and oil industries, because the typical fuelling station will be branded by the big oil companies,’ he said.
In the oil industry, which would appear to have the least to gain from the rise of hydrogen, attitudes vary wildly. ‘There are some who see hydrogen technology as one of a number of different future businesses,’ Bachmeier noted. ‘But there are also some who say: “We don’t think there is any promising business left or right of crude oil.” It’s always going to be a group of different players who will pull together to get it going — we need to bring together industrial gas industry, automotive OEM, oil company, and government support.’