The challenges facing hydrogen cars
As the world turns increasingly towards a greener future for our roads, and with ICE (internal combustion engine) vehicles being phased out across many areas of the world, alternatives are becoming commonplace. The popularity of EVs (electric vehicles) has exploded in recent years, but they’re not always suitable for every application. In fact, many people feel hydrogen is the answer, and we are gradually seeing mainstream (like Toyota and Hyundai) and commercial vehicle companies moving in this direction.
BMW is preparing to introduce a hydrogen-powered vehicle (FCEV, or fuel cell electric vehicle) to the market. Chairman of BMW Group, Oliver Zipse, spoke about the company’s plans with hydrogen. He said: “We believe in hydrogen for many reasons. We believe that […] if you want to ride emissions-free and you do not have a charging station, this is the only possibility we have. In some areas, to implement a hydrogen infrastructure is easier than an electric infrastructure.”
There are several reasons why some motorists are reluctant to invest in an electric vehicle: inability to install a home charger, lack of infrastructure, and more broadly, the often-prohibitive expense – but they might still want to drive something that’s less damaging to the local environment than an internal combustion engine (ICE) vehicle.
It might seem like hydrogen is the answer but it hasn’t seen the same growth as battery-electric vehicles.
The advantages of hydrogen
There are many reasons why hydrogen is a viable option as a fuel of the future.
No tailpipe emissions
With nations across the world aiming to dramatically reduce their carbon footprint, or even become carbon-neutral within the next few decades, hydrogen seems particularly attractive.
It’s renewable
One of the most attractive things about hydrogen is that it’s the most abundant element in the known universe. This means it’s not only readily available, but it’s infinitely renewable.
More efficient than ICE vehicles
Hydrogen is more efficient than many other energy sources. Hydrogen fuel cells contain a high density of energy, and their efficiency enables the production of more energy per pound of fuel. Hydrogen has an overall efficiency of 22% while liquid fuels such as petrol or diesel have an overall efficiency of 13%, according to the Transport & Environment.
(Though, the downside is that FCEVs aren’t as efficient as battery-electric vehicles.)
It cuts down on localised pollution
This includes noise pollution as well as air pollution. Hydrogen vehicles don’t directly generate greenhouse gas emissions, Plus hydrogen-powered vehicles are quiet like their battery-electric counterparts.
It can be used even in remote areas
While there isn’t yet a great deal of infrastructure for hydrogen cars, hydrogen can easily be made available basically anywhere, cutting down on transporting fuels and offering those living in these distant areas the opportunity to drive a greener vehicle. Perhaps the biggest advantage is within the logistics industry. Trucks doing hundreds of miles per day in rural areas where battery charging isn’t possible would benefit from hydrogen.
Why don’t we use hydrogen already?
The main reason hydrogen isn’t already being widely used is because of the high amount of energy required to extract it, and the lack of government backing. Hydrogen fuel can be extracted using a variety of processes; the most common is thermal, whereby high temperatures create steam, which reacts with a hydrocarbon to provide hydrogen. An electrolyser can also be used to create hydrogen from water molecules, there are multiple solar-powered ways to provide hydrogen, and microbes can also be used to produce hydrogen via biological reactions.
One sticking point, especially when the goal of hydrogen is to reduce emissions, is that the thermal route requires a particularly high amount of energy to operate efficiently. If those involved in hydrogen could make the greener methods of extraction more affordable, hydrogen and FCEVs could see a real boost.
At the moment there are only a few FCEVs available, and the infrastructure is very limited. In the UK, there are just two hydrogen-fuelled passenger vehicles that you can buy: the Hyundai ix35 and the Toyota Mirai. Worldwide, according to a February 2023 study, there are around 56,000 hydrogen-fuelled passenger vehicles on the roads.
To support these, there are 15 public hydrogen fuel stations in the UK. Perivale is the largest, which launched in 2021, and has a daily capacity of 1,500kg of H2.
Despite this, many are saying that hydrogen is the fuel of the future, and experts predict that 50,000 hydrogen-powered buses and 350,000 trucks will be on the motorway by 2030. But we’re far from this goal right now, and there are some disadvantages to hydrogen which are holding its adoption back.
The disadvantages of hydrogen
Why are FCEVs trailing far behind EV adoption?
It’s costly
Extracting hydrogen can be very expensive. It’s either extracted from water via electrolysis or separated from carbon fossil fuels – both processes require huge amounts of energy. Fossil fuels are often used during extraction, which undermines some of the environmentally-friendly benefits of hydrogen.
Additionally, the materials and technology required to extract the hydrogen are very expensive, and the cost for a unit of power from a hydrogen cell is currently more than most other energy sources. This alone is a huge barrier to adoption.
It requires government support and investment
A lack of clear regulatory frameworks around hydrogen extraction and fuel cells leaves major question marks around the topic and puts a barrier in front of the question of investment. Without this investment, it’d difficult to develop the technology in a way that begins to solve many of its issues.
It’s complicated to store
Storage of hydrogen is more of a challenge than for fossil fuels, meaning additional costs.
It’s extremely flammable
Safety is a concern because of the highly flammable nature of hydrogen. It burns in air at concentrations ranging from 4-75%.
Hydrogen fuel cells aren’t yet reliable
Linked to safety is the lack of durability of these fuel cells. The on-road fuel cell stack durability is around half what is required for commercialisation, and while it’s clear we’re getting somewhere, hydrogen isn’t where it needs to be.
Despite all of the pros that give hydrogen what should be a huge advantage, society isn’t quite ready for it. The right legislation, investment, education, and technology could solve a lot of the issues currently facing FCEV manufacture and adoption. Storage and transport will remain a challenge until safe and cost-effective methods are created, and serious work needs to be put into making sure the cells are more durable before they're ready for the road. While progress is being made, we’re some time away from hydrogen becoming mainstream.