Some consider hydrogen to be the fuel of the future, but how realistic is this idea? How do hydrogen-powered vehicles or fuel cell electric vehicles (FCEVs) work? Are they worth attention?
Hydrogen-powered vehicles are not supported by those who oppose the use of fossil fuels for cars. However, hydrogen is the most common substance in the universe. Hydrogen cars emit only water from the exhaust pipe. They are quiet and can travel the same distances as petrol (gasoline) or diesel vehicles.
How it works
A fuel cell electric car uses hydrogen to charge onboard batteries. Those batteries power an electric motor, and the motor turns the wheels.
The hydrogen-powered vehicle comes with a tank that is filled with hydrogen under pressure within several minutes. When this hydrogen passes through fuel cells, electricity is generated for the car’s batteries and motor.
A fuel cell stack is essentially a three-dimensional wire mesh in a liquid that causes a reaction. It has a positively charged anode at one end and a negatively charged cathode at the other.
Hydrogen atoms split into protons and electrons in this stack. Protons combine with air to form water vapor, and electrons are fed into the car’s batteries, which, via the motor, put the wheels in motion.
At high speeds, the electricity generated by hydrogen can power the motor directly, rather than accumulating in the battery. Moreover, at high acceleration, the battery and hydrogen can simultaneously drive the motor.
The advantage of hydrogen-powered vehicles is that their only exhaust is water, and they actually have their own power plant to charge their batteries.
In addition, unlike conventional electric cars, which take several hours to charge, a hydrogen car can be refueled in a matter of minutes, making it much more practical for long journeys.
A reasonable question arises: “If hydrogen cars are so great, why don’t we drive them?”
Hydrogen vehicles do a clever chemical trick, but they also have drawbacks. First, it is still a rather expensive technology: for example, the 2022 Toyota Mirai is priced between $50,525 and $67,025.
There is also a problem with refueling, as hydrogen stations are not everywhere. Hydrogen is difficult to transport and store compared to conventional fossil fuels.
These problems are understandable and can be solved over time. New technologies require gradual implementation – infrastructure development and cost reduction.
The main difficulty is not in this, but in how hydrogen fuel is produced. Despite its abundance, hydrogen makes up only one-millionth of the atmosphere. There is a huge amount of hydrogen on the planet’s surface, but mostly in chemical compounds such as water and – that’s ironic! – crude oil.
This means that it is necessary to make hydrogen fuel on an industrial scale, and in the commercial world up to 95% of all hydrogen is produced by burning fossil fuels.
This leads to complications: the operation of a hydrogen car requires the burning of oil, gas or coal, and the storage and use of hydrogen in sufficient quantities to power several vehicles.
As long as the large-scale hydrogen production is not set up as an environmentally friendly process, it makes sense to either use gasoline or diesel in vehicles, or use electricity directly from the grid to charge EV batteries.
Honda has been developing solar-powered home hydrogen stations, as well as larger plants that can be powered by waste or organic biomass. Such actions help hydrogen gain a foothold without waiting for industrial-scale production.
What we can be sure of is that hydrogen technology will be improved and cheapened in the coming years.
The energy density of hydrogen is significantly less than that of gasoline and diesel fuels, which makes it necessary to compress hydrogen.
Compressed hydrogen tanks must be very strong and withstand enormous pressure: for example, the Toyota Mirai’s tank keeps hydrogen at a level that is about 300 times the pressure of a car tire and 700 times more gravity!
There is also the problem of flammability, as pure hydrogen is very flammable. However, despite the fact that there are many protective mechanisms for charging a vehicle with hydrogen, any leak is instantly dispersed in the atmosphere. For comparison: the fog that is sometimes visible when filling the tank with gasoline is flammable fuel vapor.
There are also significant development costs, as hydrogen fuel cells are complex. It took Toyota more than two decades to improve its hydrogen fuel cell model.
The Toyota Mirai carbon fiber tank can withstand more than 200% of its normal operating pressure and remained intact even when fired from powerful rifles during tests conducted by the company’s engineers.
There are few hydrogen filling stations in the public domain today, as well as hydrogen cars on the roads. Prices are likely to decline as competition increases, and mass hydrogen production will become more common over time.
Is it worth buying a hydrogen-powered vehicle today?
If we are not talking about an environmentally conscious company that buys cars for its fleet, but about a private person – it is definitely not worth buying an FCEV because of the high cost of the car itself and the lack of a full-fledged refueling infrastructure.
When the number of hydrogen car offerings increases (and it shall happen), more refueling stations will appear, prices will fall, and then it will make sense to purchase this type of vehicle.