Hydrogen is the lightest element, the one that contains the most energy and the most abundant in the universe. In its purest form, it could be the best source of energy we have. Using it to produce power generates steam only, so it can be used without the risk of contributing to climate change. That is why for years it has been considered one of the alternative energy sources with the greatest potential for our green transformation.
Currently, however, the number of hydrogen-powered vehicles on the road is remarkably low. If in 2022 there were around 1,450 million vehicles in the world, of which close to 20 million were electric, the total number of hydrogen cars sold at the end of the same year was below 60,000. There are few hydrogen cars at the moment, and this lack of momentum is partly because hydrogen cars have taken longer to become a viable alternative to gasoline cars.
But will they ever become a real alternative to other vehicles? What are the advantages and disadvantages of hydrogen and the cars that use it?
Hydrogen, in addition to being the first element on the periodic table, constitutes around 75% of the matter in the universe and is the fifteenth most abundant element on the Earth’s surface, mainly in combination with other elements.
The first thing to know about hydrogen is that there are two ways to obtain it. The first is to extract it as a by-product of some uses of fossil fuels. This option makes sense today, since we still rely on fossil fuels. The second is through a process called electrolysis.
This process consists of the use of electricity —which can be obtained from other renewable and clean energy sources— to separate water molecules into the elements that make it up, hydrogen and oxygen. Through this process, in addition to hydrogen, oxygen is also obtained, which can be used in other industrial processes. Thus, electrolysis has the potential to enable the production of hydrogen with minimal environmental impact. For this reason, hydrogen produced by electrolysis is considered to be a green energy.
Despite their low penetration, hydrogen cars are considered a true alternative because they have tremendous potential in environmental terms. The only product derived from their use is water vapor, whose emissions do not contribute to climate change.
In essence, hydrogen-powered and electric cars have very similar engines. In both cases, the fuels they use do not require any transformation to extract energy. The main difference is that while electric ones use a battery, hydrogen ones are powered by a tank full of gas.
Since the engines are similar, hydrogen cars offer performance standards equivalent to electric vehicles, which, in turn, are now comparable to gasoline cars.
Of course, the main advantage of hydrogen vehicles is that they move in a way that is completely clean. It’s not just that they only emit water vapor, it’s also that their components are much more sustainable than electric vehicle batteries. While hydrogen fuel cells are completely renewable, lithium batteries are neither renewable nor recyclable.
And precisely because of that lack of battery, hydrogen-powered vehicles are considerably lighter than their electric competitors and don’t have to be plugged in for hours to charge. Hydrogen cars refuel in a similar way to gasoline cars, so the time they require is similar. In other words, while an electric car requires 5 hours for a full charge, the tank of a hydrogen car can be filled in 5 minutes.
The main drawback of hydrogen today is that it is still very expensive to obtain it through electrolysis. If the cost of producing hydrogen from fossil fuels is 3 times that of using natural gas as an energy source, that of producing hydrogen through electrolysis is 5 times. This proportion means that the costs of the widespread adoption of hydrogen as a fuel are still too high.
On the other hand, it is also true that, although its use to produce energy does not generate CO2 or other greenhouse gasses, the hydrogen itself, when released into the atmosphere, could contribute to climate change. Thus, its management becomes a key aspect in its use as a clean fuel at all stages of the process: from production to use, including transportation. In this sense, various environmental organizations and institutions have already called attention to the need to quantify and limit leaks.
Another of hydrogen’s problems as a fuel for vehicles is also one of its advantages: hydrogen cars refuel just like gasoline cars. This has a downside. Unlike an electric car, a hydrogen car cannot be charged at night, which means that it is completely limited by the development of the refueling network. And for now, charging points are conspicuous by their absence. Globally, the total number of hydrogen charging stations is 814, of which 245 can be found in Europe.
Another of the main drawbacks of using hydrogen as a car fuel is that it requires a lot of storage space. This is due to the chemical properties of the element itself. Hydrogen has a low energy density in relation to its volume, which is why the cars that use it need a large tank in order to store enough.
Despite the advantages they offer, hydrogen-powered vehicles will remain, for now, more of a source of curiosity than a true means of transportation. The lack of charging infrastructure, the high cost of producing green hydrogen and the greater penetration of electric vehicles will cause their adoption to be delayed.
However, it is important to note that the use of electric and hydrogen vehicles is not mutually exclusive. What’s more, given the differences between the two, the combination could be the way to go. Electric cars offer unrivaled advantages for short-distance transport, while hydrogen cars could prove to be the best option for medium- and long-distance journeys.
