What is a hydrogen fuel cell car?

Some consider it the better, cleaner future of cars as we know it, but exactly what is a hydrogen fuel cell car? On the surface, they look very similar to electric cars, but the key difference is under the hood. 

Unlike electric cars which will be the norm come 2035, hydrogen cars, also known as fuel cell electric vehicles (FCEVs), are still very much a developing market. There are quite a few different technologies across manufacturers when it comes to hydrogen cars. The main goal of all of them is to make electricity from hydrogen and oxygen. 

What do hydrogen fuel cell-powered cars emit?

Hydrogen fuel cars are designed to take in oxygen and emit only water. Not only are their emissions limited to harmless water, the cars can also take in dirty air, and clean it through their conversion processes. 

Hydrogen cars use complex air filtering systems to draw in oxygen, and this is then mixed with hydrogen. The energy produced works to power an engine that is similar in design to a traditional combustion engine, without the creation of waste gases. 

What cars run on hydrogen?

The availability of hydrogen cars is relatively limited at the moment. Being such an emerging market, the cars themselves are still expensive to buy. Ways to manufacture them on a larger scale, at a reasonable price, is still something brands are working on. As of 2021, most hydrogen cars are being marketed to business owners to purchase as fleets. This is because, as well as the high cost, there is not yet a viable network of refuelling stations available for consumers — there are approximately a dozen across the entire country. 

What car companies are making hydrogen cars?

Currently, in the UK, hydrogen cars are extremely limited in availability. Toyota and Hyundai offer their own models, with other brands yet to release any hydrogen vehicles. Given the popularity of electric cars and the nation’s increasing awareness of environmentally friendly travel, hydrogen cars may yet grow in popularity. However, until then, it’s worth asking if the cars are quite worth the investment. As well as the difficulties of fueling them, general awareness and demand aren’t quite there, which can make selling your car tricky.

How do hydrogen cars work?

Hydrogen cars convert chemicals to electricity, water, and heat. This energy is then used to power a combustion engine. Here’s a closer look at the science behind it all.

The chemical

The chemical that powers hydrogen cars is, as the name suggests, hydrogen. Hydrogen is a gas that can be used as a clean fuel. Hydrogen can be generated in a range of ways, including wind and solar power, and nuclear power.

The fuel cell

In a hydrogen fuel-cell car, this chemical is stored in a cell that is not too different to a battery found in electric cars. Unlike a battery, this cell works to generate electricity only, not to store it. A single cell isn’t powerful enough to propel a car, so cell ‘stacks’ are used to combine several together. The cell features a positively charged side (anode) and a negatively charged side (cathode), with an electrolyte in between. Inside the fuel stack, hydrogen is broken down into ions and electrons.

It is the electrons that are channelled to the cathode via a circuit and it’s this part of the process which powers the car. At the end of the process, hydrogen combines with H2O, or oxygen, and becomes water which is released via the exhaust pipe.

The engine

The engine of a hydrogen car doesn’t vary very much from those found in a petrol car. The key difference is that they burn clean i.e. the only thing they emit is water, no harmful CO2 emissions. 

Are hydrogen cars better than electric cars?

Hydrogen cars are a bit of a divisive subject. Some argue that they are superior to electric cars as they only emit water. Others say that hydrogen is the greener fuel source, as electricity itself can still come from fossil fuels. Counter to that is the fact that hydrogen can also be made through methods that are not particularly green. Plus, transportation is also an issue as the chemical needs to be delivered to its fueling station. 

In terms of car ownership, there is far more knowledge around electric cars, and that includes servicing. Hydrogen cars are much newer, and rarer, so finding a professional to fix any issues will be hard, to say the least. 

On the plus side, hydrogen cars are generally able to go further on a single charge than electric cars. Charges take less than five minutes. This has led to the suggestion that the perfect future of cars involves electric cars for short journeys and daily driving, and hydrogen cell cars for industrial vehicles covering more miles. That said, only time will tell if hydrogen cars gain their place in the mainstream car market. 

Ready to sell your car?

Ready to learn more about valuing, maintaining, and selling your car? Check out more of our guides here, covering everything from hybrid and electric car depreciation, to converting your car to dual-LPG fuel.

How to sell an electric car
Electric cars — should you buy or sell?
What is a hybrid car and how do they work?
LPG cars — the ultimate guide
How long does it take to charge an electric car?
Do electric cars pay the congestion charge?
Do electric cars need servicing?
The ultimate Birmingham Clean Air Zone (CAZ)
Euro 6 compliance & emission standards