Rolls-Royce's Hydrogen Capabilities Await Market Maturity

Rolls-Royce has no imminent plans to actively continue its exploration of hydrogen propulsion, explaining that “as an engine manufacturer, demonstrating [its] ability to use hydrogen fuel is now done.” Instead, with a recent hydrogen combustion test campaign now concluded, the engine maker suggested it instead needs to “pace that program to industry development.”

Speaking at a media briefing in July 2, Rolls-Royce president of civil aerospace Rob Watson suggested that having demonstrated a modified  Pearl 15 engine could be run on 100% hydrogen, the practical feasibility of hydrogen combustion was no longer the OEM’s primary focus. “We’re really pleased that we’ve been able to demonstrate the capability to burn 100% hydrogen through a full flight cycle, so it’s a rigorous test, but now we need to see where the industry is going to go,” he suggested.

Earlier this year, a four-year partnership between easyJet and Rolls-Royce concluded with the test run of a modified Rolls-Royce Pearl 15 using 100% hydrogen. Described as an “industry first” by the partners, the engine reached full take-off power in its test rig, situated at NASA’s Stennis Space Center. Announcing the milestone in March, Rolls-Royce added that the project had achieved its objective to validate combustion, fuel and control system technologies “and demonstrated the safe use of hydrogen through design, commissioning, maintenance and testing.”

At the time, Rolls-Royce chief engineer for the hydrogen demonstrator programme Adam Newman explained that “the insights gained, many of which are fuel agnostic, will now be applied across our future programs, including UltraFan.” The project partners had previously ground run a Rolls-Royce AE2100 turboprop on 100% hydrogen from the UK’s Boscombe Down test site.

“There’s a much bigger industrial question about how you deliver that hydrogen at a platform level, through an aircraft level… and also how you deliver that hydrogen at an industrial scale. That’s not our area of focus,” Watson told journalists. In recognition of Rolls-Royce’s “strong sustainability agenda,” he instead suggested that “continuing to drive the efficiency and capability of [its] current products” remained a core focus.

Alternative Sustainability Strategies

“As we’ve said consistently, we really see SAF [sustainable aviation fuel] as the first step in that sustainability story,” he reiterated. All in-production Rolls-Royce engines to date have demonstrated the ability to run on 100% SAF. Additionally, following the company’s formal step back from electric propulsion activities in November 2024, Watson added: “I think we’ve always been clear that fully-electric was a general aviation-scale opportunity… and we made a conscious, strategic decision that we weren’t going to pursue that market.”

Nevertheless, Watson suggested that “hybridization is really interesting,” and one which could present opportunities for large-engine business aviation applications. He underlined that Rolls-Royce now views the role of electrical power for its core engine market as being part of a hybrid solution within the powertrain.

Building on capability built by the Rolls-Royce electrical business segment, land-based hybrid technologies being deployed “in a number of applications, primarily around UK sovereign capability.” The company now envisages some of these being applied in the civil aerospace sector.