Hhydrogen is a tempting substance: the lightest element. When it reacts with oxygen, it produces only water and releases a lot of energy. The invisible gas seems to be a clean fuel of the future. Some of the world’s top automotive executives hope this will dethrone the battery as the technology of choice for zero-emission driving.
Our EV Mythbusters series has looked at concerns ranging from car fires to battery mining, range fears to cost and carbon footprint concerns. Many critics of electric vehicles argue that we should not abandon gasoline and diesel engines. This article asks the question: can hydrogen provide a third way and overtake the battery?
Many of the strongest claims about hydrogen’s role in the automotive world come from CEOs at the heart of the industry. Japan’s Toyota is the most vocal proponent of hydrogen, and its chairman, Akio Toyoda, said last month he believed the share of battery cars would peak at 30%, with hydrogen and combustion engines making up the rest. Toyota’s Mirai is one of the few hydrogen-powered cars that is widely available, alongside South Korea’s Hyundai’s Nexo SUV.
Oliver Zipse, the boss of German manufacturer BMW, said last year: “Hydrogen is the missing piece in the puzzle when it comes to emission-free mobility.” BMW may be investing heavily in battery technology, but the company has its BMW iX5 Hydrogen fuel cell car in testing, albeit using Toyota fuel cells. Zipse said: “One technology alone will not be enough to enable climate-neutral mobility worldwide.”
Hydrogen is the most abundant element in the universe, but that doesn’t mean it’s easily available on Earth. Most pure hydrogen today is made by splitting carbon from methane, but that produces carbon emissions. Emission-free ‘green hydrogen’ comes from electrolysis: the use of clean electricity to split water into hydrogen and oxygen.
To use hydrogen as a fuel, it can be burned, or it can be used in a fuel cell: the hydrogen reacts with the oxygen from the air in the presence of a catalyst (often made of expensive platinum). That strips electrons that can run through an electrical circuit, charging a battery that can power an electric motor.
Hydrogen offers four-minute refueling, higher payload and longer range, according to Jean-Michel Billig, the chief technology officer for hydrogen fuel cell vehicle development at Stellantis. (The Mirai travels 400 miles when it needs to refuel.) Stellantis, which last month began producing hydrogen vans in France and Poland, is targeting companies that want vehicles that are in constant use and don’t want the downtime required for charging.
“They must be on the road,” Billig said. “A taxi that doesn’t run is a loss of money.”
Stellantis thinks it can bring the sticker price down. Billig said he expected hydrogen mobility, or BEV, to be equivalent from a cost perspective by the end of this decade — although the company will make both.
Many energy experts do not share the enthusiasm of the hydrogen car manufacturers. Tesla boss Elon Musk describes the technology as ‘fool sells’: why use green energy to make hydrogen if you can also use the same electricity to power the car?
Every transformation of energy involves wasted heat. This means that hydrogen fuels inevitably deliver less energy to the vehicle. (These losses increase much further if the hydrogen is burned directly or used to make e-fuels that can replace gasoline or diesel in a noisy, hot combustion engine.)
David Cebon, professor of mechanical engineering at the University of Cambridge, said: “If you use green hydrogen, it takes about three times more electricity to make hydrogen to power a car than just to charge a battery .”
That might improve something, but not enough to challenge the batteries. “It’s hard to do much better,” Cebon said.
Michael Liebreich, the chairman of Liebreich Associates and the founder of the analyst firm Bloomberg New Energy Finance, created an influential “hydrogen ladder” – a ranking that ranks the use of hydrogen based on whether there are cheaper, easier or more likely options. He put hydrogen for cars in ‘the queue of doom’, with very little chance of even a niche market.
Can hydrogen overtake batteries in cars? “The answer is no,” Liebreich said without hesitation. Automakers betting on a big share for hydrogen are “simply wrong” and heading for an expensive disappointment, he added.
The main problem for hydrogen cars is not the fuel cell, but actually getting the clean hydrogen where it is needed. The gas is highly flammable – with all the associated safety risks – must be stored under pressure and leaks easily. It also carries less energy per unit volume than fossil fuels, meaning it would require many times more tankers unless electrolysers are used on site.
Investments are being made in the hydrogen supply, with heavy government subsidies in the US and Europe. But so far there has been a chicken-and-egg problem: buyers don’t want hydrogen cars because they can’t refuel them, and there are no gas stations because there are no cars. According to the European Hydrogen Observatory, there are 178 hydrogen filling stations throughout Europe, half of which are in Germany. Compare nine British hydrogen stations with 8,300 filling stations or 31,000 public charging locations (not including plugs at homes).
Why then does the International Energy Agency think hydrogen will account for 16% of road transport by 2050 on its way to net zero? The answer lies mainly with larger vehicles such as buses and trucks.
Liebreich said he was convinced batteries would still dominate the energy supply for heavy trucks — to the point that he would co-found a truck charging company. “There may be some hydrogen in trucks, but that will be the minority,” he said.
Even Toyota acknowledges that hydrogen in cars “has not been successful” so far, mainly due to the lack of fuel supply, according to chief technical officer Hiroki Nakajima, who spoke to Autocar in October. Trucks and long-distance buses offer better hopes for the technology, although it is also prototyping a hydrogen version of its Hilux pickup.
The economics of hydrogen will change as governments’ enthusiasm increases or decreases. Other things could change: the technology could improve (within limits) and make the gas more attractive, and prospectors might be able to find cheaper ‘white hydrogen’ drilled out of the ground.
Yet the die seems to have been cast for cars: batteries are already the choice after gasoline for almost every manufacturer. Fewer than 300 hydrogen cars have been sold in Britain in the past 20 years, compared to 1 million electric cars, according to the Society of Motor Manufacturers and Traders.
The dominance of batteries is likely to increase even further as money poured into research and infrastructure addresses questions about range and charging times. Compared to that flow of investment, hydrogen is just a trickle.
Hydrogen proponents are now faced with the question of whether they can build profitable businesses in longer-distance heavy-duty road transport. They need a quick answer about where they can source enough green, cheap hydrogen – and whether the gas could be better used elsewhere.