Hydrogen cars, or hydrogen fuel cell cars, are a new type of passenger vehicle separate from the petrol, diesel, hybrid or electric cars that form the majority of cars on British roads.
You may know about LPG (Liquid Petroleum Gas) cars, but hydrogen-powered cars are very different and are much closer to being electric cars, since there is no internal combustion engine in the car at all. Instead, there’s a fuel cell, which generates electricity using hydrogen – but more on that later.
Hydrogen cars just need to be filled up with hydrogen at a pump and the only tailpipe emission is H2O – yes, just water. As hydrogen is the most common element in the universe it’s not likely to run out like petrol or diesel will.
Hydrogen cars are rare now but this may change in the future – and as more appear on the roads you’ll want to know more about them so that you can compare with a future electric car. After all, from 2025 in the UK, you won’t be able to buy a new car that doesn’t feature an electric motor.
In this article we’ll look at how hydrogen cars work, how they compare to conventional electric cars, look at some examples of hydrogen cars in the UK and consider their advantages and disadvantages. Read on to find out all you need to know about hydrogen fuel cell cars.
How does a hydrogen fuel cell car work?
Let’s start with the short version and move on to a more technical description. As the driver of a hydrogen car, just like with a petrol or diesel car, you don’t need to know much more than this: you put hydrogen in using a fuel pump at a filling station, which is used as fuel to generate electricity. This electricity is used to power the wheels.
Now for the long version. When you put hydrogen in the car, it’s stored in a secure fuel tank like petrol or diesel is.
It’s fed into the fuel cell, which is what generates the electricity. It uses chemistry to combine hydrogen and air (oxygen) and generate electricity. Inside the fuel cell is a liquid with a positively charged anode on one side and a negatively charged cathode on the other, a bit like a battery.
In the cell, hydrogen atoms split into protons and electrons – the former turning into the exhaust product (pure water) and the latter providing the power for the car’s electric motor. Like a battery pack, there are lots of smaller reactions happening in the fuel cell to provide plenty of power for the motors.
There’s a battery on board too, which saves power for later – usually when you’re accelerating and more power is needed. However, the fuel cell often sends power directly to the motors.
Are hydrogen cars better than electric cars?
Let’s look at how hydrogen cars are different from normal electric cars, and work out which kind of car is best for you.
The electric motors that are used in hydrogen cars such as the Toyota Mirai are fundamentally the same as the ones in normal electric cars such as the Renault Zoe, Volkswagen ID.3 or Hyundai Kona Electric.
They simply take energy and turn it into rotational movement – the difference is that in a normal electric car, this energy only comes from an on-board battery that needs to be charged up, while in a hydrogen car it comes from an on-board generator that uses hydrogen.
This means that a hydrogen car can be taken from empty to full in a few minutes at a fuel pump, like a petrol or diesel car – so in this way they’re better than electric cars, as it’s convenient.
Yet it’s impossible to say that hydrogen cars are better or worse than electric cars because there simply aren’t enough of them yet. There are very few for sale and even the ones that are on sale are extremely niche products. Electric cars are much more mainstream.
This brings us onto the advantages and disadvantages of hydrogen cars when compared to electric cars.
What are the advantages and disadvantages of hydrogen cars?
The main advantage of hydrogen cars is that they produce no emissions at the tailpipe – just water. This benefit is the same as with a normal electric car, and puts both at the forefront of emission-cutting tech in the automotive world.
The advantage of hydrogen cars over and above electric cars is that you can fill one up with a fuel pump, which takes a couple of minutes. Like with a petrol or diesel car, you just fill up, pay and go on with your day, rather than having to wait potentially hours for the same amount of range to be added to the battery pack.
Hydrogen isn’t totally green, though – it’s clean when used in your hydrogen car but to get the (liquid) hydrogen into the fuel pumps, it requires a lot of energy and a lot of the current production is done using fossil fuels, so it contributes to global warming more than, say, an electric car charged using power from a wind farm.
It is hoped that hydrogen production will become fully sustainable as demand rises and investment is put into finding better ways of producing it.
Another disadvantage — and this is the main one at the moment — is the infrastructure. In the UK there are a tiny number of hydrogen pumps where you can fill up – it’s not like they’re on every street corner.
In an electric car you need to work out where a nearby car charging port might be, but it’s likely to be relatively close by. With a hydrogen car you could end up a long long way from a fuel station. Most are in London at the moment.
Hydrogen is quite expensive, too. While a full charge of an electric car costs around £8 from a home charger, a full tank on a Toyota Mirai is roughly £75.
These infrastructure problems and costs will go away with time, though – as more and more people buy hydrogen cars, the costs will go down and there will be more fuel stations to use. Right now, an electric car makes more sense to the vast majority of people.
Will hydrogen cars take over from electric cars in the future?
It’s impossible to work out how the future will pan out, but there’s one thing that’s abundantly clear: the future will see us driving electric cars instead of petrol or diesel ones.
What’s less clear is whether we’ll be filling up with hydrogen or charging them at home. What seems likely at the moment is that we’ll have both – which can only be a good thing.
For some people, charging up at home is convenient and cheap. But for others, they can’t charge at home and need to refill quickly – so hydrogen is looking like a great solution for them.
Car manufacturers appear to be focusing mostly on battery electric vehicles at the moment, as there are few fuel cell cars known to be in development, but that could change. Hydrogen also looks like a good solution for trucks and vans that need to refuel quickly.
Is hydrogen dangerous?
We bet that when you first heard about hydrogen-powered cars, you thought about the Hindenburg disaster where an airship full of hydrogen exploded. Yes, hydrogen is flammable, but so is petrol – and you carry that around with you in your car all the time.
The modern world is a much safer place and the car companies have thought of this. The hydrogen used in cars is pressurised and the tanks on board are designed to contain this extreme pressure and more, so there should be no more danger than a normal car.
Toyota has laid out the safety systems in place for the Mirai hydrogen car. The tanks are designed not to leak – they are extremely strong – and in any accident the hydrogen system shuts itself off automatically.
None of the hydrogen-associated parts are near the cabin either, and the brand says that even if hydrogen were to escape, it’s lighter than air so it quickly evaporates into the atmosphere – unlike inside that huge blimp mentioned above.
What hydrogen cars are available in the UK?
If you want a hydrogen car, you don’t have a lot of choice at the moment. There’s the Hyundai Nexo, which is a small SUV or the Toyota Mirai (due to be replaced with a next-generation version soon).
Honda is another high-profile maker that has experimented with hydrogen power, and its fuel cell car is called the Clarity. It’s not on sale currently but it’s set to arrive in the next few years.
BMW, Ford, Nissan and Mercedes have all been linked to hydrogen car development, but for now, the most notable upcoming model is the BMW i Hydrogen NEXT SUV — a concept car that hints at a new model from the German brand with this kind of powertrain.