What is a Hydrogen Fuel Cell Vehicle and How Does it Work?

Like Electric Vehicles (EVs), Hydrogen Fuel Cell Vehicles (HFCVs) have zero emissions, emitting only water vapor. But despite their environmental benefits, you are likely to only find HFCVs in California, the only state with a hydrogen fueling station network. In 2022, there were 17,000 HFCVs on US roads, all of which were in California. However, with increasing global eco-awareness and strong investments being made into HFCV research and production, they could become more common in the near future.

How Do Hydrogen Fuel Cell Vehicles Work?

HFCVs use an electric motor to turn wheels in the same ways as battery-electric cars and can still be classified as e-cars. However, HFCVs produce electricity themselves. Instead of being fueled by a battery, they are fueled by a fuel-cell stack where pure hydrogen from one or more of the car’s tanks passes through a membrane. This combines with oxygen from the air to produce electricity to turn the wheels, as well as water vapor, producing no other emissions.

The scientific process that takes place within the fuel cell is known as reverse electrolysis. The electricity that is generated can take two routes that can happen simultaneously. This electricity can flow to the electric motor to drive the car and to the battery to charge it in case it is needed.

Like natural gas, most hydrogen is derived from fossil fuels. The pure hydrogen (H2) required for HFCVs usually requires energy to separate it from a compound like natural gas (CH4). When the pure hydrogen (H2) is run through the fuel cell, the hydrogen gives back energy as electricity as soon as it is combined with oxygen (O). This results in water vapor (H2O) being emitted from the exhaust pipe. This means that the HCFV is locally emission-free, keeping the air in cities clean.

HFCVs are fuelled at hydrogen fueling stations where refueling takes around five minutes.

When Were the First Hydrogen Cars Created? How Have Vehicles Evolved?

Hydrogen-fueled vehicles have a long history, but they weren’t made available commercially for sale until the Toyota Mirai came onto the market in 2015. The first hydrogen-powered vehicle was actually created back in 1807 by a Swiss inventor called Francois Isaac de Rivaz.

The first fuel cell was later developed by Welsh scientist Sir William Grove in 1839, although this was used in domestic settings and not in cars. In fact, fuel cells were used in rockets by NASA in the 1950s and 60s, decades before being used in cars.

Mercedes presented a hydrogen-powered car in 1993 but it was not made commercially available. Later in 2008, the Hyundai Tucson Fuel Cell was released in very limited quantities, preceding the commercial release of the Toyota Mirai in 2015. Since this date, more HFCVs have become available on the market, although they are not as commercially available as EVs.

The evolution of HFCVs has become possible following the development of internal combustion engines (ICE) and EV technologies. However, HFCV technology still requires some work. While they only emit water vapor, the process of “steam methane reforming” in which the pure hydrogen required is produced still has a carbon footprint. For HFCVs to be completely green, the industry needs to invest in producing hydrogen through renewable energy sources. It is also possible to create “green hydrogen” that emits zero emissions from electrolysis. This uses clean electricity to split water into hydrogen and oxygen. However, the efficiency of electrolysis is half that of a battery-powered EV.

That said, hydrogen is a by-product that is treated as waste in many industrial processes. In the future, it is hoped that this hydrogen could be upcycled to fuel HCFVs. Excitingly, hydrogen can also be produced anywhere where there is access to water and electricity. There have been examples of hydrogen being produced directly at filling stations in Belgium and Germany.

How Is a Hydrogen Fuel Cell Vehicle Different From a Regular EV or Hybrid EV?

Like other EVs, HFCVs also benefit from regenerative braking. In this process, the HFCV will redirect its braking energy back to the buffer battery. This provides extra power during short accelerations. It also allows the fuel cell to idle when low power is needed.

Unlike with EVs however, the amount of energy stored is not determined by the car’s battery size but by the size of the hydrogen fuel tank.

What Are Modern Hydrogen Vehicles on the Market Currently?

Toyota has been recognized as the company most dedicated to developing HFCVs. Since its release in 2015, it has sold around 14,300 Mirais in the US. A decade after its initial release, the newer Mirai has a driving range of up to 400 miles and improved aerodynamics.

Toyota is also developing an HFCV version of its Hilux pickup and is also creating prototypes for heavy-duty hydrogen buses and trucks, testing commercial vehicles with Coca-Cola.

In 2024 Honda released the CR-V e:FCEV which not only has a hydrogen fuel cell, but a battery that can be plugged in to provide 29 miles of range. This is the first plug-in HFCV on the market. However, it is only available for lease, and only in California.

BMW is also invested in hydrogen technology, having recently announced its iX5 SUV. The SUV has a range of up to 500 kilometers, with two hydrogen tanks that can be refueled in 4 minutes. That said, it is not yet available for purchase.

Hyundai has also produced a number of HFCVs. They released the first hydrogen-powered SUV, the Nexo in 2018. The current model has a 500-mile range. Meanwhile, Hyundai’s N Vision 74 will be a hybrid HFCV that combines a hydrogen fuel cell with a lithium-ion battery resulting in impressive acceleration, a 372 driving range and 670 combined horsepower. It is set for a 2026 release. Hyundai has also produced a heavy-duty truck, the XCIENT, which has an all-electric range of 400 kilometers.

How Successful Have Hydrogen Cars Been?

While the technology behind hydrogen cars is exciting for eco-technology, they have not seen much commercial success. It has been reported that Hyundai only sold 1600 Nexo SUVs in six years. While in the UK, only 300 HCFVs were sold across a 20 year period.

Elon Musk has described the fuel cell technology behind HFCVs as “fool sells”. He argues why use green electricity to produce hydrogen, when that same energy could be used to power a car. It follows that fuel cell technology adds an extra step to eco-friendly driving.

The issue is not the hydrogen cell, but the method of producing hydrogen:

• Electricity required: According to David Cebon at the University of Cambridge, it takes three times more electricity to make the green hydrogen required to power a car than it does to power a battery.
• Flammability: Hydrogen is highly flammable and must be stored under high pressure. It also leaks easily.
• Energy per unit: Hydrogen requires more tankers as it carries less energy per unit volume than fossil fuels.

Moreover, the lack of a refueling network outside of California makes the possibility of future success doubtful. Buyers won’t buy cars because they can’t fuel them, and fueling stations are limited because there are no cars. As of February 2024 the UK has nine fueling stations, while Europe has 178, half of which are in Germany.

Furthermore, Toyota’s chief technology officer, Hiroki Nakajima, admitted that the sales of its Mirai were not successful during the Japan Mobility Show in October 2023. He explained that the lack of hydrogen fueling stations was a cause of this. Despite this, he said that Toyota was committed to improving the technology.

How Much Do the Cars on the Market Generally Cost?

HFCVs are not cheap. The Toyota Mirai has a starting price of $50,190. Similarly, Honda’s CR-V e:FCEV begins at $50,000. While standard EVs can cost just as much, the cheaper models start from $29,280.

The high price tag is due to a variety of reasons including the use of expensive platinum required in electricity generation and the lack of high-volume production of HCFVs in general.

Hydrogen fuel itself is expensive too. In June 2024 the average price of hydrogen fuel across California was a whopping $32.94 per kilogram. This would make a full 5-kilogram refill of the Toyota Mirai around $164.70. Occasionally manufacturers will offer drivers complimentary hydrogen to entice them to drive HFCVs, but once this runs out the fuelling process is costly.

Should Buyers Consider Hydrogen Cars?

Driving hydrogen cars is similar to driving standard EVs. They are smooth and quiet, though they are slower than regular cars as there is no transmission.

The Toyota Mirai has 120 horsepower, which isn’t enough to get onto a highway. While this is supplemented by a high-voltage battery to assist with acceleration, it may not make you confident driving at high speeds.

Moreover, if the hydrogen components of the car need servicing, it will require a highly trained mechanic to do so. There are also rules and regulations for this to prevent any escaping hydrogen from causing an explosion.

For eco-conscious drivers who don’t want to wait long periods of time to charge their car, however, an HCFV may be a good option as they can receive a full charge in as little as three minutes. That said, this all depends on there being a charging station available in your area. The likelihood of being able to drive an HCFV outside of California at the moment is very slim, but for those living in the Golden State, you can check the status of hydrogen stations online.

The green possibilities that HCFVs offer make them an interesting proposition for the future of eco-friendly vehicles. However, the lack of HCFVs on the market coupled with the scarcity of fueling stations makes the prospect of ownership for most people almost impossible.

There are also questions about the process in which the hydrogen used to fuel HCFVs is produced, as some methods emit carbon, meaning that technically not all HCFVs are completely emission-free.

That said, many manufacturers are committed to improving the technology so a brighter future for HCFVs may still be on the horizon.