Electric vehicles (EVs) are generally seen as the future of sustainable mobility, and sales of EVs, which have grown exponentially in recent times, reflect this sentiment.

Hydrogen, which was once considered a viable option for emissions-free transport, has been almost forgotten about. Although consumers do have the option to buy from a couple of select hydrogen-powered cars on the market, demand is extremely low. And fueling opportunities are practically non-existent.

Hydrogen power is far from new, as car manufacturers have been experimenting with the technology for a while. They see it as a worthwhile venture, as hydrogen is the most abundant resource in the universe, which once refined, can power a car cheaply and with near-zero environmental effect.

However, little progress has been seen since hydrogen was first viewed as a potential fuel, and when compared to the advancements and adoption of electric cars, hydrogen power is essentially being left behind. The pre-existing electric infrastructure gave EVs a major leg up and R&D has helped fill in some of the efficiency gaps along the way.

So that begs the question, is hydrogen power still a realistic option for powering future cars?

Why hydrogen remains attractive

One of the main advantages that hydrogen power would have over current electric cars is the refill time and process. Filling a car up with hydrogen is almost exactly the same process as filling the car with petrol or diesel, and it only takes a fraction longer, about five minutes to fill a regular tank. Anyone familiar with electric cars know the pain of having to wait from six to 12 hours for it to fully charge, depending on the type of outlet and charger used.

Couple this with the abundance of hydrogen. As the largest constituent gas in Earth's atmosphere, hydrogen manufacturing stations could be placed anywhere. This may not be as convenient as an electrical outlet swap in an owner's garage, but it does reduce the pollutive road miles logged by transporting traditional fuels from refinery to end use, and that includes many fossil fuels burned to provide the electricity itself.

This might sound like an outright win for hydrogen, but the biggest hurdle to adopting hydrogen power is the infrastructure that currently exists. To put this into perspective, there are just three hydrogen stations in all of New York City, serving almost 20 million people. So, unless you live close to one of these stations, and plan to only commute to other areas with hydrogen stations, owning a hydrogen-powered car is not practical. Along with this and some other obstacles, there is still a long way for hydrogen to go to become a mainstream power source for cars.

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Hydrogen complements, doesn't compete with EVs

Another aspect of hydrogen power that hinders adoption is its efficiency. Hydrogen power is significantly less efficient than EVs. Since hydrogen isn’t readily available on its own, it has to be extracted from the atmosphere. Once it is in the car, the hydrogen mixes with oxygen within a fuel cell stack and creates the electricity that gives the motor power.

This is called an energy vector transition: electricity is used to create the hydrogen, and then the hydrogen is converted to electricity. With any energy transition, losses are inevitable, and some estimates indicate only 38% of the original watts used to create the hydrogen result in on-road locomotion. EV enthusiasts and analysts alike point out that electric power is more direct and there is less energy loss in comparison.

However, an important point of clarification is that hydrogen cars are not meant to fully replace EVs but rather complement them. Hydrogen is the cleanest fuel in the world, and for that reason, a combination of hydrogen and electric power is very desirable. This is because producing lithium-ion batteries is a very energy-intensive process, which creates many tons of carbon dioxide. Lithium must also be mined from remote locales. So even though electric cars do not produce harmful gases themselves, their manufacture is still having an impact on the environment.

What is the future of hydrogen power for cars?

There are only two hydrogen-powered cars that are on the mainstream market today; these are the Hyundai Nexo and the Toyota Mirai. However, there is news that some of other major car manufacturers, namely BMW and Land Rover, are planning on bringing out their own hydrogen-powered cars in the next five years.

Concept art of a hydrogen-powered Land Rover Defender. Source: Land Rover

This is why experts in the field are encouraging hydrogen to be accepted as a part of a wider “hydrogen economy,” as building thousands of new stations just for hydrogen is not practical or efficient. Instead of a "one-fuel-fits-all" approach, manufacturers, regulators and consumers a better off considering fueling needs based on applications.

For example, electric heavy goods vehicles have been much less popular than passenger EVs, as the battery packs are larger to support a higher capacity, which takes longer to charge. Idle time for a semi-truck means it is not actively making money, so it is a more expensive vehicle all around. However, if key trucking depots had on-demand hydrogen fuel generation, large trucks would be better able to take advantage of its fuel density and refueling rate, and spend more time hauling freight.

The idea of this is that hydrogen power should be incorporated into the entire energy sector where it makes the most sense, rather than as a competitive replacement to technologies that are further developed and more broadly supported by existing infrastructure.

At the moment hydrogen power is still in its infancy, and hydrogen cars are still quite expensive. As with all new technology, as it develops it will become cheaper and more accessible, and more mainstream adoption will occur.

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We have seen this process unfold already with EVs. While there are still a lot of obstacles to overcome and many questions remain around the practicality of it, hydrogen power is making progress, and it would be unwise to totally rule out it making an impact on sustainable energy. Whether that is directly with cars or the whole energy sector, we will have to wait and see.