Airbus is accelerating work on the development of a hydrogen-powered fuel cell engine as part of its studies into a zero-emission aircraft scheduled for service entry by 2035. The European aerospace group company revealed its plans during a Sustainability Summit held in Toulouse, France, on November 30.
As part of its wider preparations for hydrogen-powered air transport, Airbus announced a partnership with space group Ariane to build a liquid hydrogen refueling system in Toulouse by 2025. During the summit, it also reported that it is working with green hydrogen specialist HyPort to have a hydrogen production, storage, and distribution facility in operation at Toulouse-Blagnac Airport in 2023.
Airbus said it will start ground and flight testing the proposed fuel cell engine architecture onboard its ZeroE hydrogen-powered demonstrator aircraft towards the middle of this decade. The A380 MSN1 flight test aircraft for new hydrogen technologies is now undergoing modification to carry liquid hydrogen tanks and their associated distribution systems.
"Fuel cells are a potential solution to help us achieve our zero-emission ambition and we are focused on developing and testing this technology to understand if it is feasible and viable for a 2035 entry-into-service of a zero-emission aircraft,” said Airbus vice president for zero-emission aircraft Glenn Llewellyn. “At scale, and if the technology targets were achieved, fuel cell engines may be able to power a 100-passenger aircraft with a range of approximately 1,000 nautical miles. By continuing to invest in this technology we are giving ourselves additional options that will inform our decisions on the architecture of our future ZeroE aircraft, the development of which we intend to launch in the 2027-2028 timeframe.”
Airbus has identified hydrogen as one of the most promising alternatives to power a zero-emission aircraft because it emits no carbon dioxide when generated from renewable energy. When it announced its Zero E project in September 2020 the company said it will choose between three airframe configurations in 2024 and aim to have a technology demonstrator ready to fly in 2025, leading to a full program launch in 2027 and entry into service in 2035. Earlier this year, Delta Air Lines signed an collaboration agreement to support the project.
Three Hydrogen Airliner Concepts in Contention
One of the three designed unveiled in 2020 is a blended wing airframe that Airbus indicated would be able to carry up to 200 passengers on flights of around 2,300 miles. The exceptionally wide fuselage, in which the wing merges with the main section of the aircraft, would provide space for a cabin as well as for hydrogen storage and distribution. However, in his presentation this week, Llewellyn suggested that the blended wing concept is the least-likely option to be selected.
Airbus is also working on a more conventional narrowbody model that would carry between 120 and 200 passengers on sectors of around 2,300 miles. The propulsion system would be based on a pair of modified gas turbine engines powered by liquid hydrogen that would be stored and distributed via tanks located behind the rear pressure bulkhead. The design features swept-back outer wing surfaces.
The third design is a 100-seat twin turboprop. It too would feature modified gas turbines fueled by hydrogen and, said Airbus, would fly to a range of up to around 1,000 nm.
During the summit, Llewellyn explained the two primary ways one can use hydrogen as a power source for aircraft propulsion. The first involves hydrogen combustion in a gas turbine, the second through the use of fuel cells stacked together to convert hydrogen into electricity to power a propeller engine. A hydrogen gas turbine can also work with fuel cells instead of batteries in a hybrid-electric architecture. Airbus continues work on both potential applications.
Airbus’s has explored the possibilities of fuel-cell propulsion systems for aviation for some time. In October 2020, Airbus created Aerostack, a joint venture with ElringKlinger, a company with more than 20 years of experience as both a fuel cell systems and component supplier. In December 2020, Airbus presented its pod concept, which included six removable fuel cell propeller propulsion systems.
HyPort and Ariane Are Fuel Supply Partners
France-based HyPort is a joint venture between Engie Solutions and the Regional Agency for Energy and Climate in Occitanie. Its work with Airbus is intended to create a blueprint for establishing hydrogen fueling infrastructure that builds on the Hydrogen Hubs for Airports initiative that the manufacturer announced in 2020.
Initially, the facility at Toulouse-Blagnac Airport will produce around 400 kg of hydrogen each day and this will be enough to power around 50 ground transportation vehicles. "Our involvement with HyPort demonstrates the tangible progress Airbus is making on its journey to secure the future energy ecoystems of tomorrow," said Karine Guenan, Airbus's vice president for ZeroE Ecosystem. "Using hydrogen to decarbonize all airport-associated ground transport in the 2020 to 2030 timeframe will pave the way for hydrogen availability for zero-emission aircraft by 2035."
In tandem with this project, the ArianeGroup, which is jointly owned by Airbus and Safran, will now design, produce and support the operations of a liquid hydrogen fueling system specifically for the ZeroE demonstrator during the ground and flight test campaign. The company has more than 40 years of experience working with the fuel for the propulsion systems used by the Ariane space rockets.
"Many of the technologies required for a zero-emission aircraft are already available in other industries and liquid hydrogen handling is no exception," said Sabine Klauke, chief technical officer of Airbus. "Preparing for the entry into service of a zero-emission aircraft in 2035 means that we need to mature all of the required technologies in parallel."
French Carmaker Joins Airbus Electrification Team
In another announcement made during the Sustainability Summit, French carmaker Renault signed a research and development agreement with Airbus aimed at enhancing what the companies call their electrification roadmaps through improvements in battery technology. The collaboration, which covers so-called technology bricks related to energy management and battery weight, will help Airbus develop technologies associated with future hybrid-electric aircraft. The agreement also calls for joint studies into the best pathways to move from current cell chemistries such as lithium-ion to all solid-state designs expected to double the energy density of batteries by 2030.
The joint work will also study the full lifecycle of future batteries, from production to recyclability, to prepare the industrialization of future designs while assessing their carbon footprint across their entire lifecycles.
“This cross-industry partnership with Renault Group will help us mature the next generation of batteries as part of Airbus’ electrification roadmap,” said Airbus chief technical officer Sabine Klauke. “Reaching net zero carbon emissions by 2050 is a unique challenge that requires cooperation across sectors, starting today. Bringing together Renault Group’s experience in electric vehicles with our own track record in electric flight demonstrators will allow us to accelerate the development of the disruptive technologies required for future hybrid aircraft architectures in the 2030s and beyond.”
Klauke also explained that the partnership will foster the emergence of common technical and regulatory standards to help meet the industry’s climate targets.
“For the first time, two European leaders from different industries are sharing engineering knowledge to shape the future of hybrid-electric aircraft,” added Renault Group vice president of engineering Gilles Le Borgne. “Aviation is an extremely demanding field in terms of both safety and energy consumption, and so is the car industry. At Renault Group, our 10 years of experience in the electric vehicle value chain gives us some of the strongest feedback from the field and expertise in the performance of battery management systems. Driven by the same ambition to innovate and reduce the carbon footprint, our engineering teams are exchanging with those of Airbus to converge transversal technologies that will enable both hybrid aircraft to be operated and the vehicles of tomorrow to be developed.”
Developers of new electric aircraft, such as the eVTOL design intended for urban air taxi services, are increasingly turning to the automotive sector for help with battery technology. Companies including Hyundai, Toyota, Stellantis, and Geely are investing in the sector.
On November 29, Airbus joined four other major aerospace groups in announcing plans to develop a new hybrid-electric propulsion system that could reduce fuel burn and emissions for narrowbody airliners. The Sustainable Water-Injecting Turbofan Comprising Hybrid-Electrics program is backed by MTU Aero Engines, Pratt & Whitney, Collins Aerospace, and GKN Aerospace. It is based on adapting Pratt & Whitney's current Geared Turbofan engine.
