Embracing the Rainbow: Exploring Hydrogen’s Role in Decarbonising Aviation at Regional Airports

by Paul E Eden (Regional Gateway/CirculAIRity) With hydrogen considered to be a key element in decarbonising aviation, regional airports are likely to provide proving grounds for critical related technologies. However, hydrogen is not a straightforward solution and the challenges are great, as Paul E Eden discovers.

Particularly for smaller aircraft, there is perhaps a role for battery and hydrogen fuel cell propulsion, the latter consuming hydrogen as a fuel and exhausting water as waste product.

Hydrogen fuel cells already power ground vehicles to a limited extent, and applications for hydrogen as a fuel for electricity generation and even domestic heating have been suggested, not least under the UK government’s Hydrogen Strategy.

The SAF connection – How hydrogen could support sustainable aviation fuel production

Which is to say that were hydrogen to be used as a fuel on a macro scale, then existing steel-based infrastructure, pipelines, storage tanks and so on associated with hydrocarbon fuels could not be used, since hydrogen reacts with steel.

Another challenge lies in gaseous hydrogen’s very low volumetric energy density compared to hydrocarbons, likely restricting its fuel use to ground and building applications unless it can successfully be stored and moved in bulk, in liquid form.

Hydrogen extraction is the most energy-intensive stage in the SAF production process.

“Waste heat from industrial processes can be used instead of electricity. So can heat from the sun ....

(T)he very best locations for real-world trials are smaller, regional airports, where modified infrastructure may be installed with minimal disruption and stakeholders remain close for easy discussion and expedited progress.

Chikhani (CirculAIRity CEO and founder) cautions that hydrogen alone is not the solution to humanity’s future energy requirements – and therefore neither will it entirely power tomorrow’s airports and aircraft.

“Firstly, hydrogen is difficult to handle,” he says. “It can’t be moved or stored like natural gas, for example. Hydrogen needs stainless steel or glass vessels, or maybe some very specific plastics.

It just leaks from steel and with its activation energy being so low it is very combustible – static from clothing is a sufficient ignition source.

“Aluminium aircraft and steel infrastructure have been built around and matured on almost a century’s worth of kerosene – Jet A1 – being the primary energy source for aviation.

By its nature, aviation is among the most difficult sectors to decarbonise. In 2024 it was a relatively small contributor to the world’s total carbon emissions at around three per cent, although its effect on global warming was surely greater through other high-altitude emissions, including water vapour.

The latter is volumetrically more significant than CO2 as a greenhouse gas and has significant climate effects, albeit shorter-lived for each emission, than CO2. More worryingly, however, it enhances the warming effects of the latter.

As other industries successfully decarbonise, aviation’s contribution to global warming will become proportionally greater and it is important to realise that the goal here is to reduce global warming for the benefit of the planet and continued survival of society.

This is not about making aviation greener for accounting purposes, this is about stopping emissions and ultimately reversing the damage already done.

Regional airports are the obvious crucibles in which the aviation industry might trial hydrogen and other energy technologies, proving them in limited commercial service before any extension into major hubs.

Chikhani and Klaaßen (Julian Klaaßen, the BSR HyAirport Project’s Financial and Communications Manager) are optimistic about the likelihood of success, while acknowledging that fundamental questions remain, such as: Where does the hydrogen come from? Who makes it? Who sells it? How is it regulated? What infrastructure is required and who pays for and maintains it?

“We are seeking answers,” Klaaßen says. “In the process, we are speaking to stakeholders whom, as airports or aviation operators, we have never spoken to before, because we can only answer these questions in co-operation with other industries. Without co-operation, we will never achieve our goals.”