- By Ben Morris
- Business Technology Editor
On a typical day, 1,300 planes take off and land at Heathrow Airport, and to keep them running requires around 20 million liters of jet fuel every day.
That’s the equivalent of filling your car about 400,000 times.
It’s a large-scale operation, with fuel piped directly to the airport from refineries and then stored at two facilities known as fuel farms.
Matt Prescott, head of carbon strategy at Heathrow, said: “The amount of fuel going through Heathrow is huge. It accounts for around half of the UK’s jet fuel needs.”
Heathrow Airport itself does not buy or sell fuel but relies on airlines and their suppliers.
However, they have to think about infrastructure, allocating space for storage and pipelines, and making sure airlines and fuel companies have everything they need.
“The real issue is building enough capacity to ensure that the airport has resilience in place,” Mr Prescott said.
However, when it comes to fuel, airports around the world are having to think again.
Sustainable aviation fuel (SAF) – fuel that does not come from fossil fuels – is one option. Airlines already use it, often mixed with regular jet fuel.
For airports, supplying SAF is simple – it can be delivered through existing pipelines.
But many people are skeptical whether SAF can be produced cheaply enough or in large enough quantities to meet the needs of the aviation industry remains to be seen.
Therefore, there is a lot of interest in hydrogen, which can store a lot of energy and, when used as a fuel, does not produce CO2.
To be useful for aviation, hydrogen needs to be liquid, which involves cooling it to minus 253C.
Handling liquids at such temperatures is extremely challenging. If given the chance, liquid hydrogen will “boil” and escape as a gas – potentially becoming a hazard.
Therefore, tanks, pipes and hoses must all be further insulated to keep the liquid cold.
France’s Air Liquide has extensive experience in this field. For about 50 years, it has provided cryogenic hydrogen for Ariane’s rockets European Space Agency (ESA).
The company produces more than a million tons of hydrogen a year, and in addition to fueling rockets, its hydrogen is used in trucks and all kinds of industrial processes.
“This gives us a very strong foundation of technology and industrial know-how in this area,” said Erwin Penforis, senior managing director of the company’s global hydrogen business.
Over the past three years, in partnership with Airbus and France’s largest airport operator, ADP Group, Air Liquide has been researching the potential of hydrogen in business aviation.
It is also part of the H2Fly consortium that successfully flew an aircraft using liquid hydrogen this summer. For Air Liquide, this was an opportunity to test a hydrogen aircraft fueling system.
Airlines are keen to know whether hydrogen planes can be refueled as quickly as current planes, as fast turnaround times are crucial to the industry.
“Can we deliver several tons of liquid hydrogen within 15 minutes or 20 minutes,” Mr. Penforis said. We have the technology for this. We are adjusting it – but the answer is yes.”
However, installing the necessary equipment to store and distribute hydrogen at airports will not be cheap. Consulting firm Bain & Company It is estimated that it could cost a lot of money up to billions of dollars per airport.
A startup, Universal Hydrogen, says it has a solution. It involves performing all the complex steps in hydrogen processing away from the airport, possibly at a gas production facility.
The company has developed special tanks to hold liquid hydrogen (UH calls them modules), which can then be transported to the airport. These modules are designed to be installed directly into the aircraft, where they can be plugged into the propulsion system.
No need for pipes, hoses and pumps.
The modules are extremely well insulated and can hold hydrogen in liquid form for four days. The two modules will hold 360kg of hydrogen and can fly the aircraft 500 miles, plus 45 minutes of flight reserve.
Universal Hydrogen is modifying a regional airliner, introducing a fuel cell that can convert liquid hydrogen into electricity and connecting that battery to an electric motor that will drive the propellers.
Larger doors are being installed so the modules can be loaded into the aircraft. If all goes according to plan, test flights will begin next year.
Mark Cousin, chief technology officer at Universal Hydrogen, said hydrogen will most likely be used for regional flights, but conventional jet fuel will still be needed for long-haul flights.
“Handling fuel in a different way – as we are proposing – makes sense because you are not trying to convert existing fuel supply infrastructure that airlines need to retain for other parts of their fleet.”
It remains unclear whether hydrogen will become the main fuel for aviation. Hydrogen-powered aircraft are still in the early stages of development.
Unlike current planes that can store fuel in the wings, hydrogen planes will have to store fuel in the fuselage, cutting down on space for passengers.
There’s also the question of whether there will be enough green, environmentally friendly hydrogen to meet demand.
Prakash Dikshit, who works on airport planning and development for consulting firm Landrum and Brown, said it is unclear which path the aviation industry will take.
“I think everyone in the aviation industry realizes that net zero is something they need to aspire to. How we get there and the economics of getting there are unclear at this point.
“Hydrogen-fueled aircraft – while there may be some test flights in the next decade, large-scale deployment using hydrogen certainly seems far off. And may not even be certain .”