Rolls-Royce and EasyJet have completed ground tests with an early concept demonstrator for a hydrogen propulsion system that they hope will eventually be capable of powering narrowbody airliners. The partners announced on November 28 that they recently ran a modified Rolls-Royce AE 2100 A turboprop airliner engine on green hydrogen made from wind and tidal power inspired by the United Nations-backed Race to Zero campaign to achieve net zero carbon emissions by 2050.
A series of ground tests conducted during November with the concept demonstrator at the UK’s Boscombe Down defense research facility has prepared the way for full-scale ground tests using the Pearl 15 turbofan engine that Rolls-Royce developer for Bombardier’s Global 5500 and 6500 business jets. Eventually, the engine maker intends to scale up the technology to work with large turbofans needed for aircraft such as the Airbus A320 family operated by Easyjet across Europe.
The low-cost airline and Rolls-Royce embarked on their partnership to develop hydrogen propulsion for commercial flights as part of the H2Zero program. EasyJet is also involved in parallel work with GKN Aerospace to develop both direct hydrogen combustion technology under the H2JET program and hydrogen fuel cells through a project called H2GEAR.
The AE 2100 engine powers the 50-seat Saab 2000 regional airliner, as well as various military aircraft such as the Lockheed P-3 Orion surveillance platform and the C-130 troop carriers. For larger commercial aircraft, like the 150-seat A320s, the direct combustion technology would need to work with more powerful engines like the CFM International Leap family.
Rolls-Royce and EasyJet aim to be ready to deploy hydrogen propulsion for commercial flights in the mid-2030s, a target aligned with the objectives of Airbus's own Zero E program to produce new hydrogen-powered airliners.
The green hydrogen used for the first test with the concept demonstrator was provided by the European Marine Energy Centre at its facility in Eday in the Orkney Islands off the north coast of Scotland. The organization runs a hydrogen production and tidal test facility at that location and participates in early work to establish the infrastructure needed to supply hydrogen for air transport.
The renewable electricity generated by wind and tidal power runs an electrolyzer to produce green hydrogen through electrolysis. The hydrogen is then "squeezed" to compress it from 20 bar to 200 bar pressure to maximize the amount available in an aircraft fuel tank; the engine then combusts the hydrogen in place of Jet-A fuel.
Easyjet and Rolls-Royce are now preparing for a second set of ground tests with a full-scale powertrain. At some point, they intend to be ready to evaluate a hydrogen powerplant in flight tests using still unspecified aircraft.
“The success of this hydrogen test is an exciting milestone,” commented Rolls-Royce chief technology officer Grazia Vittadini. “We only announced our partnership in July and we are already off to an incredible start with this landmark achievement. We are pushing the boundaries to discover the zero carbon possibilities of hydrogen, which could help reshape the future of flight.”