What is a hydrogen car?

  • Your guide to hydrogen fuel cell cars
  • DIscover what they are and how they work
  • Are hydrogen cars the future of motoring?

With all the talk of petrol and diesel cars being phased out by 2030 and sales of electric vehicles starting to climb, it may have escaped your attention that it's possible to buy hydrogen cars in the UK.

Hydrogen fuel cell electric vehicles, to give them their full name (FCEV for short), are ones that use compressed hydrogen to generate electricity, which is then used to power the car.

Blue 2016 Toyota Mirai front three-quarter

For that reason they drive a lot like an electric vehicle – almost silently and with instant torque - but with a far longer range than a car with batteries as its only energy source.

Their main attraction is that they emit nothing more harmful from their exhausts than clear air and water. In fact, it's possible for hydrogen cars to clean particulates from the air, actively benefiting the environment as they drive along.

Hydrogen cars FAQs

Here we've answered the most common questions the Parkers editorial team are asked about hydrogen cars. If you have a further question you would like answering then send us an email.

Which hydrogen cars can you buy in the UK? 

If you are considering a brand new hydrogen car then the choice is incredibly limited, with just two to choose from.

Grey 2021 Hyundai Nexo front three-quarter

Embracing the SUV zeitgeist is the Hyundai Nexo, a smoothly-styled five-seater with decent boot space to make it fit in with family life. 

Because it generates the electricity it needs to propel the car when it needs it, the battery pack is just 1.6kWh, yet it can store enough compressed hydrogen to give it a range of 413 miles.

It's not cheap, though, but cutting edge technology rarely is; at £69,495 the Nexo is the priciest Hyundai on sale.

Blue 2021 Toyota Mirai front three-quarter

Your only alternative, for the time being at least, is the more traditional four-door saloon-bodied Toyota Mirai, due to arrive in showrooms in spring 2021.

It's a far more elegant car than the first-generation Mirai, with more passenger space and a range of approximately 400 miles between refills set to make it more popular.

Prices for the latest Mirai are yet to be confirmed.

Will there be other hydrogen cars in the near future? 

Yes, but not many due to the Catch-22 issue caused by a lack of a hydrogen filling station infrastructure as outlined below.

Most car companies are working both indvidually and collaboratively on hydrogen FCEV technology, with Honda and Mercedes-Benz already offering such vehicles for sale in selected markets - but not yet in the UK.

Silver 2018 Mercedes-Benz GLC F-Cell front three-quarter

Expect to see a much greater number of battery electric vehicles (BEVs) go on sale before hydrogen models gain popularity.

Even when hydrogen vehicles are more readily available, the technology is likely to be limited to larger, more expensive cars, with smaller, cheaper models expected to remain as BEVs.

Hydrogen also suits large vehicles such as trucks and buses far better than a battery-only electric solution, meaning over the next decade the technology will be honed more quickly by long-distance real-world development.

What are the drawbacks of hydrogen cars? 

Hydrogen itself is the most abundant element in the atmosphere, so there’s no shortage of it, but with present-day technology it costs a significant amount to prepare and compress it so it’s suitable for use in a vehicle, hence the small number of refuelling stations in the country.

At the time of writing, there are fewer than 20 hydrogen filling stations in the UK, with most of those being concentrated in the south-east of England. 

The other main disadvantage is the sheer amount of electrical energy required to create the hydrogen in the first place – ironically in a lot of cases predominantly generated using fossil fuels. We’re not living in a society that’s truly geared-up for hydrogen fuel cell motoring just yet, although in Norway many of the newer hydrogen filling stations are powered by electricity generated from solar energy.

Are hydrogen cars easy to refuel? 

Yes, and the process is much more like refilling a petrol or diesel car than it is to plug in a fully electric one.

Refilling a hydrogen fuel cell car

One key difference is that the hydrogen filler nozzle clamps to the car - if you have ever refilled an LPG-powered car, it's a similar experience. This is a safety measure to prevent high-pressure, very cold hydrogen leaking during the refill.

Once clamped on, the liquid hydrogen is pumped into the tank, pausing every so often to depressurise to ensure as much fuel as possible can be delivered.

When the display on the filling pump confirms it's finished, simply unclamp the nozzle and return it to its holster.

How do hydrogen cars work? 

The science behind hydrogen cars is complex, but in a simplified sense a fuel cell creates electricity, which is then used to feed a battery or drive the wheels, or a combination of the two.

Hydrogen fuel cell

Said electricity is produced in a unit called a fuel cell stack, in which a chemical reaction occurs that converts hydrogen into electricity, clean air and water.

You’re able to refill a hydrogen car with compressed H2 in around the same time it takes to top up a conventionally engined car with petrol or diesel, but this depends on the type of filling point you’re using. More advanced (and expensive) units can refill in as little as five minutes, while lesser ones work at lower pressure and so can’t refill as quickly.

Are hydrogen cars safe? 

While the thought of driving around with tanks of pressurised hydrogen may sound a little worrying, car firms and their suppliers have been working on such technology for years and there’s little reason to expect anything other than total reliability.

Hyundai's Nexo remains the only hydrogen-powered car to be crash-tested by the safety experts at Euro NCAP, gaining a five-star rating when it was assessed in 2018.

The carbon fibre tanks are tested to remarkable lengths, including getting shot with various military hardware and dropped from significant heights.

Much of the other hardware used is similar or the same as that in electric vehicles, so again there’s little to worry about there. We’ve heard no anecdotal reliability issues with these either.

Do hydrogen cars represent the future of motoring? 

They’re certainly not suitable for many buyers as things stand right now, simply because there aren’t many hydrogen filling stations in the UK. However, considering the massive benefits of this type of power generation compared with using fossil fuels – either in conventional combustion engines or to run the national grid – it’s likely we’ll see the infrastructure growing increasingly quickly during the 2020s.

Hydrogen fuel cell filling station

It’s going to rely heavily on investment, both from large multinational companies and governments, in order to grow at any pace, though. For that reason it’s likely we’ll see an increasing number of commercial vehicles powered by hydrogen first. 

Will all cars eventually be hydrogen-powered? 

This seems unlikely. While no-one knows exactly what'll happen moving forwards, the basic premise is that battery technology could progress to be as efficient as a fuel cell vehicle. This is because effectively a fuel cell vehicle stores its energy in hydrogen, which is then converted to electricity. If the battery can store enough for most drivers' usage on its own, then we wouldn't need the fuel cell at all. 

Hydrogen fuel cell in Toyota Mirai

It's already becoming clear that for short-range work, such as inner cities, the best solution is a small electric car that can be quickly recharged. As charging times drop and battery technology improves, so the requirement for hydrogen fuel cell vehicles falls. Whether that'll happen quickly enough is anyone's guess, though. 

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