However, progress has not been as fast as the world needs it to be. “Keeping alive the goal of limiting global warming to 1.5°C requires the world to come together quickly,” International Energy Agency (IEA) executive director Fatih Birol said as he unveiled an updated version of the IEA’s net zero roadmap in late 2023. “The good news is we know what we need to do – and how to do it.”
Alternative fuels are helping to reduce reliance on polluting energy sources, but many widely recognised alternatives, such as solar, hydo and wind, need boosting with newer alternatives. One solution riding to the potential rescue is hydrogen.
Such a bold target by the IEA to get to net zero “really made people’s ears and eyes and brain sit up and say: ‘Well, what are we going to do now?’” says Tim Mays, director of UK-HyRES, the UK’s hydrogen research hub, which recently funded 10 new projects – totalling £3m – that will help bring about new hydrogen solutions to climate issues.
In its roadmap, the IEA places a premium on hydrogen, requiring it to be deployed in heavy industry and long-distance transport as a fuel stock, accounting for around 10% of total final consumption by 2050. While it might not seem like a major component of our energy mix now, it has been earmarked as a key fuel to bridge us into the low-carbon future.
One problem, many potential solutions
The range of projects UK-HyRES is funding speaks to the scale of the problem and the potential solutions being proffered. They include projects looking at: the safe transportation of hydrogen by sea and storage in port bunkering facilities; how North Sea offshore hydrocarbon extraction locations could be repurposed for hydrogen production; whether new techniques can produce hydrogen from seawater; and how hydrogen can be more sustainably and efficiently produced through new electrolysis methods – among others.
Tim Mays
“The original motivation for this was to help us manage the supply-demand mismatch for renewable electricity generation,” says Mays. “But the idea of a hydrogen economy has expanded way beyond that.”
It’s a plan that many say is much needed. “Hydrogen offers enormous decarbonisation potential across a broader range of end uses than direct electrification, but it is inherently less efficient and for now more expensive than, let’s say, battery energy storage technologies on a cost-per-kWh basis,” says Oliver Curnick, professor of electrochemical engineering at Coventry University.
More than 100 million tonnes a year of hydrogen is already used worldwide to refine petroleum and for the production of ammonia and other chemicals. “But only a fraction of this is green hydrogen produced by electrolysis,” says Curnick.
Hydrolysis is one of the areas UK-HyRES is targeting. “Electrolysis of water normally assumes that the water is pretty clean,” says Mays. “But there’s a lot of seawater around an island nation like the UK, so there are problems electrolysing seawater because of the chlorine and salt in it.”
One of the projects the hub has funded in its 2025 round is to understand how to develop optimal technologies to tackle the issues inherent with seawater, including the corrosion of metal components.
Green hydrogen
It’s important not to think of hydrogen as a one-size-fits-all solution. So-called grey hydrogen comes from the steam methane reformation process without capturing the greenhouse gases that are expelled during the process of production. That makes it the easiest and most common form of hydrogen on the market, but also one of the most polluting – albeit less than fossil fuels.
-copy.jpg?sfvrsn=384a5c11_0 "Oliver Curnick (2023) copy")
Oliver Curnick
Decarbonising this grey hydrogen will be important for bringing about a cleaner, greener future, says Curnick. “We’ve a huge challenge just to convert existing production from ‘grey’ to ‘green’ to decarbonise current use cases before we can even begin to address other applications.”
One way of doing so would be to pair up electrolysers, which split water into its constituent parts of hydrogen and oxygen, with the burgeoning wind power we have across the country – and the wider world. “In 2024, Britain spent £1bn on wind energy curtailment,” explains Curnick. “If we could site electrolysers close to these wind generators offshore, then we could be using these spare electrons to make huge quantities of cheap, green hydrogen.” It would be a “win-win” situation, he adds.
But the use of hydrogen generally is one that most sectors feel comfortable pursuing. “Hydrogen has a sort of Swiss army knife approach to applications,” says Mays. “It’s a rich and interesting area, and one that will be part of the energy mix as we transition away from fossil fuels to renewables and net zero.”
Under Mays, who acts as its director, UK-HyRES is a national hub that started with 14 different research projects across seven UK universities, relating to the production, storage, distribution and use of hydrogen, as well as alternative carriers to hydrogen such as ammonia.
“The concept of the whole hub is really to identify, then prioritise and then deliver solutions to technical challenges that will enable and accelerate hydrogen to be used in a future low-carbon energy system,” says Mays.
Storage: key to survival
One of the projects Mays is working on is around storage – something he describes as a “major issue if you want to use liquid hydrogen in aerospace”. A major problem is that hydrogen is particularly low-density. Per unit mass, 1kg of hydrogen contains as much energy as 3kg of methane, but its density makes it extraordinarily difficult to store. “The storage issue is to try to engineer systems that can increase the density of hydrogen and therefore reduce the volume requirements for it,” says Mays.
Similarly, repurposing spent geological formations such as salt mines and caverns to store hydrogen seasonally – by using the summer sun to make hydrogen that is then stored away and redelivered in the winter – could help tackle energy problems. “Hydrogen is like a glue or a bridge that keeps all our requirements together,” says Mays.
It’s only through tackling all aspects of the energy cycle when it comes to hydrogen that the world can really make a difference to its energy mix. “Establishing the hydrogen backbone and further transmission networks – such as those in the North Sea – will enable large-scale, cross-border hydrogen distribution, allowing affordable hydrogen produced in one location with lower energy prices to be transported to higher-value markets across Europe,” says Markus Kösters, head of commercial at hydrogen company Lifte H2.
Markus Kösters
One way that international trade and transport could be made easier is by repurposing the infrastructure that already exists. “There are already over 10,000km of natural gas pipelines under the North Sea, which could be repurposed to carry hydrogen,” says Curnick. “There are some technical challenges here due to the differing properties of hydrogen versus methane, but these are well understood and surmountable at what we believe is a reasonable cost.”
The use cases
Achieving cross-border transport and trade in hydrogen will be important given the range of sectors the energy source can be used in. “An example of hydrogen’s transformative potential can be seen in steel manufacturing,” says Kösters. “Direct reduction processes can leverage clean hydrogen to replace fossil-based feedstock, particularly in applications where electric solutions do not achieve the required temperature. This can significantly reduce carbon dioxide emissions from one of the world’s largest industrial emitters.”
Kösters adds that in parallel there will be a strong need for hydrogen elsewhere. “Specific sectors such as heavy-duty transport face practical challenges when relying on battery-electric solutions alone,” he explains, pointing to the strain on power grids when large fleets of buses or trucks charge simultaneously on an electric grid. Hydrogen could step into the breach. “Hydrogen offers an efficient alternative, with faster refuelling times and the ability to manage energy supply across multiple energy vectors,” he says.
But despite the wide range of potential use cases, there needs to be targeted attempts to capitalise on it, Kösters says. A scattergun approach will waste time, effort and money. “The hydrogen revolution is pivotal in accelerating global transition to net zero, particularly by providing a scalable, flexible and clean energy carrier for hard-to-abate sectors,” he says. “However, the real challenge for policymakers and industry is to identify and focus on those applications with the most significant impact on emission reductions – where hydrogen either has no viable alternatives or provides clear cost advantages over other solutions.”
One problem that needs to be overcome before hydrogen can be widely used is the safety question. “There are new and innovative announcements with regards to hydrogen and its production each week,” says Rachael Burns, director of Hydrogen Safe, a specialist training provider educating individuals and organisations to work with and around hydrogen safely. “The challenge comes when we consider how these projects will be delivered and by whom.”
Channelling support in the right direction
It’s for this reason that the UK-HyRES hub is so important to our energy future. However, it’s just the beginning, and not the be-all and end-all of the process. “Hydrogen is a fast-moving area, so we wanted to make sure we had enough money to be able to fund new ideas and new projects as they came along,” says Mays. The 10 new projects recently supported by the hub augment its initial 14, all trying to reach the same aims.
“What’s needed is a long-term strategic investment in hydrogen R&D in the UK, along the lines of what has been made in battery technologies via The Faraday Institution, for example,” says Curnick. It also needs support for academia from both the private and public sectors. “There’s often been a problem with university research not being taken up and then moved up from the so-called technology-readiness-level scale to pilot scale and then to commercial scale,” says Mays.
“One of the challenges we face is that the hub is working side by side with industry. It’s not as if we have a project and we invite industry. They’re the ones that come forward with ideas and projects that need to be done to resolve particular technical challenges in relation to their business. So we’re working very much in partnership, co-creating and co-delivering these projects. The main funding does come from the government, but industry co-funding is a very, very important part of that investment.”
The projects, therefore, live or die on the potential of industry to recognise that net zero is a good goal to target – and working in tandem with the brightest minds to achieve it. But Mays hopes that a rallying movement focused around the hub, in its aims toward meeting broader global goals, can get at least much of the way there to save our climate while ensuring the world still works, powered by a new, cleaner alternative fuel.
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