The A380 transformed into a flying test bed for hydrogen fueled turbofan engine
The world’s problems may not ever be addressed in an airport lounge, but during a 24-hour layover in Munich and after a gin and tonic, at least one of the world’s problems appears to have a solution. The problem: fuel. The solution: hydrogen.
Filling my time with two English newspapers and listening to BBC World News is killing my mood. Here Britain is suffering from fires after record-breaking heat. It is hot out there. The heat has dried out fields, hedges—what forests still remain.… Climate change is caused by burning too much fossil fuels. It’s hot enough to melt the roads. Crews were watering the roads ahead of Tour de France riders. Sri Lankans overthrew their government, protesting a lack of fuel, among other things. Sri Lanka’s economy is near collapse. In Ukraine, the war is wreaking havoc on the global supply of food and fuel. I arrived from Budapest, where traffic on the bridges was blocked by protests against an increase in the income tax. Why the increase? The government needed money to subsidize its fuel costs.
It’s all about energy. Either we are not getting enough of it, we are not getting it at a cheap enough price, we are invading countries to get it, we are using the wrong kind, or we are using too much of it. In countries where there is enough energy, we generate greenhouse gases and increase the global temperature. Here we are flying around the world, driving our cars and trucks and—this time of year—cranking up the air-conditioning so that we are comfortable. In countries where there is not enough fuel or fuel is not available at a low cost, they riot to get it, so that they too can drive their trucks and cars and turn on their air conditioners. In India, where already unbearable temperatures broke a hundred-year-old record (up to 140°F), a burgeoning middle-class responded by turning up their air-conditioning, straining a dysfunctional grid already prone to blackouts. What powers most of India’s electric power plants? The most polluting fuel of them all: coal.
Why Hydrogen?
Hydrogen is the perfect fuel.
As anyone who has studied chemistry knows, hydrogen burns with oxygen and gives off energy and water. No carbon goes into the equation or into the air. There simply is no fuel that is cleaner burning or more efficient in producing energy that is not radioactive.
Why Not Hydrogen?
Hydrogen is not being used for the simple reason that it is not currently readily available in a usable state.
Hydrogen that is usable as a fuel is more expensive to produce than hydrocarbon fuels for reasons we have covered in detail here.
Hydrogen does not exist in a usable state, that is, elemental hydrogen. Most of the hydrogen on Earth is so tightly bonded with oxygen that the energy required to separate it makes it more costly than coal, oil and gas.
So, there you have it. No business and only the most well-intentioned and well-off consumer will buy anything that runs on hydrogen. A case in point is the Honda Clarity, an ever-so-green hydrogen fuel cell vehicle. Honda stopped production of the Clarity in 2021 after too few sales.
Why Not an Electric Aircraft?
In the weight-conscious industry that is aviation, heavy batteries just don’t make sense. Lithium-ion batteries have one-fiftieth of the energy density of jet fuel. And all the weight of the batteries has to land, unlike the weight of jet fuel that is lost during flight, so a battery-powered aircraft must be further bulked up to withstand repeated landings.
Airbus is publicly open to the idea of a battery-operated aircraft, but realistically the company states that battery design is just not feasible. The company sees all-electric aircraft—if they ever were to come into commercial service—as smaller planes with different engines that are intended for short-haul flights.
“Battery technology is not moving at the pace we want, and this is where hydrogen comes in,” said Glenn Llewellyn Airbus, VP of Zero-Emission Aircraft, in a previous article. “It’s got several thousand times more energy per kilogram than what batteries could have today.”
The A380 Flies Again—But On a Different Mission
Airbus is testing hydrogen fuel for aircraft and so is Boeing. I read about this with great interest in the day’s Financial Times available in the airport lounge.
One might expect an airplane, its tanks filled with hydrogen for fuel, to be lighter. And what could be better for an industry that associates economy with weight? That would be true if the hydrogen were stored as a gas. But that would take up too much space. Picture the entire cabin area reduced to a hydrogen gas tank.
The Airbus test system on the A380 has 400 kg in four tanks that need to be stored at −253°C. The cryogenic equipment needed to keep hydrogen liquid takes back quite a bit of the space saved from not having it in a gas state and you now have a heavier system.
Earlier this year, Airbus launched a new phase of its ZEROe (zero emission), a program with a mission to have a zero-emission aircraft in service by 2035. The latest news was that the testing would take to the air in a test aircraft, with a hydrogen engine mounted—somewhat oddly—off the top of the fuselage of an A380.
The A380 resigned as a test platform? The massive, double-decker A380 was to have been the company’s flagship aircraft. Hailed as the world’s largest passenger aircraft, it was to have surpassed Boeing’s ultra-successful 747 jumbo jet. So large was the A380 that not all airport runways were long enough to accommodate the plane and airport gates needed to have two-tiered jetways installed to load and unload passengers on the aircraft’s two decks. But the A380 was to suffer the same fate as the Concorde—and be abandoned despite its superior capability and technology.
But technologists can take heart in knowing that the A380, now gutted and revamped as a flight test laboratory, could usher in a potentially world-saving technology: hydrogen.
Overjoyed are the ZEROe test engineers that they’ve been given the cavernous interior of the company’s flagship jet, rather than the drab and compact confines of the military cargo plane often used as test beds.
“The A380 MSN1 is an excellent flight laboratory platform for new hydrogen technologies,” says Mathias Andriamisaina, Airbus ZEROe Demonstrator Leader on the company’s website. “It’s a safe and reliable platform that is highly versatile to test a wide range of zero-emission technologies. In addition, the platform can comfortably accommodate the large flight test instrumentation that will be needed to analyze the performance of the hydrogen in the hydrogen-propulsion system.”
When Can We Fly on Hydrogen?
But before you can expect your next flight on a clean, carbon-free fueled jet, keep this in mind:
- Airbus is only now flight-testing hydrogen fuel with its ZEROe program.
- The Airbus A380 being used in the ZEROe program is only burning hydrogen in a test engine mounted on a stub off the top of the A380’s fuselage. The aircraft’s four main engines are conventional turbofans that will burn jet fuel.
- The A380 test aircraft testing won’t achieve a “mature technology readiness level” until 2025.
- Airbus is not planning to have a zero-emission aircraft in commercial service until 2035.
The A380 is not Airbus’ first hydrogen entry but is part of the company’s plan to rid itself of hydrocarbon dependance. In July, the company announced that it joined the €1bn Hy24 investment fund, along with FiveT Hydrogen, which provides investment management for clean hydrogen ventures, and Ardian, Europe’s largest private investment company, for the purpose of building out a hydrogen infrastructure.
Airbus has three hydrogen-powered concept aircraft, shown during the July Farnborough (UK) airshow. We have covered the concept aircraft in detail in a 2020 article but here’s a quick review:
- A two-turbofan model, with a capacity for fewer than 120 to 200 passengers and a range of over 2,000 nautical miles. This aircraft could be the successor of the A320, which has this year surpassed the Boeing 737 as the most popular passenger aircraft. It has hybrid-hydrogen (hydrogen and electricity) turbofan engines, with liquid hydrogen storage and a distribution system located behind the rear pressure bulkhead.
- A two-turboprop model, with a capacity for fewer than 100 passengers and a 1,000 km range. It is powered by 8-blade hybrid-hydrogen 8-blade turboprop engines. The liquid hydrogen storage and distribution system are located behind the rear pressure bulkhead.
- A blended-wing body (BWB) model with two hybrid-hydrogen turbofan engines and a range of 2,00 km. The extra-wide interior allows more options for hydrogen storage and distribution. The liquid hydrogen storage tanks are stored underneath the aircraft’s wings.
Airbus Leads
While transportation is the third biggest contributor of greenhouse gases globally (behind #1 electricity and #2 manufacturing and construction of all energy-using industries, aviation accounts for only 2.5 percent of global CO2 emissions, according to a 2018 Our World in Data report. It’s a drop in the bucket, right?
Passenger and freight traffic on land contribute over 5 times as much greenhouse gas emissions as aviation, according to the International Energy Agency (IEA). True, but that’s still over a billion tons of CO2 in the air. A 2020 study published in the Atmospheric Environment journal that also measured nitrogen oxide found that the global aviation industry contributes only 3.5 percent of the total climate change.
Airbus has been developing the hydrogen-fueled engine since 2015 for its A350-1000 aircraft, according to the ZEROe site. The company seems to be quite serious about its energy transformation to hydrogen, seen as “radical” by the industry media, judging by the resources the company has committed to it. This is not merely environmental posturing, a reaction to flight shame, the hesitancy of travelers to fly for fear of destroying the Earth in the process, and the threat of a loss of business as travelers keep to surface routes or simply stop traveling. On the contrary, it seems to be a concerted effort to turn aviation around, to stop the reliance of fossil fuels, to remove carbon dioxide from the air.
As a business, Airbus must certainly have its eye on the eventual decrease in the cost of hydrogen and the eventual depletion and scarcity of fossil fuels and operating costs in the long term, but for now, at least, the company is acting as a leader, with its moral compass showing the rest of the industry true North, and that it is able and willing to incur the additional cost of pioneering a new technology for the sake of the common good for us all.