Hydrogen-electric propulsion systems delivering continuous power of between 350 and 500 kilowatts could be in production by 2030, according to Josef Kallo, co-founder and chief technology officer of H2Fly. Speaking on Wednesday at the Aero Friedrichshafen show in Germany, he said that over the same four- to five-year period, further investment in the sector could result in functional models and applications for a 1.2-megawatt system able to power larger aircraft.

Germany-based H2Fly, which is owned by eVTOL aircraft manufacturer Joby Aviation, is working to progressively increase the power density of its fuel cell systems, with efforts currently focused on its 175-kilowatt H2F-175 unit. The focus of development efforts for its third-generation technology is to establish stability in terms of control, operations, handling, functionality, and reliability, and as work shifts to a fourth-generation unit, H2Fly’s 65-strong engineering team will scale up the technology and add improved components.

“Over the last nine months, we have learned a lot from the testing and also how to control the fuel cell systems and [hydrogen fuel] storage,” Kallo told AIN. “We think we can control the systems with stability and reliability during ground tests, and will then be able to give [aircraft] OEMs stable high-performance operations.”

Less stable, however, is the economic context for aviation’s path to reducing dependence on fossil fuels, according to Kallo. Acknowledging the recent collapse of equity prices in the wake of U.S. tariffs imposed on other countries, he said that the fate of the financial markets will be critical to investment prospects for the sector.

“We have enough money for the next couple of years, but we [and the wider industry] will need a tremendous increase after that, so we will have to use every cent efficiently,” Kallo commented.

Renewable Energy Rises

At the same time, Kallo feels that there is a path to resolving concerns about the availability of the supporting infrastructure required for hydrogen-powered aircraft that recently prompted Airbus to push back its projected ZeroE timeline for bringing a 200-seat airliner to market by around five years. In recent years, H2Fly has played a leading role in several European Union-funded projects to advance the hydrogen ecosystem for aviation.

“The hydrogen economy depends on having installed renewable power [to generate green hydrogen], and worldwide we are seeing incremental increases in the availability of solar and wind power, so this is becoming cheaper,” Kallo said. “In fact, in the U.S., it is really cheap compared to other energy sources, and that makes me confident that the conversion of this energy to hydrogen will also ramp up, although at the moment there is competition over where renewable energy should go.”

In around 12 months, H2Fly expects to be ready to announce which aircraft manufacturers it will partner with to complete the industrialization of its fuel cells. “Just look at the [hydrogen] aircraft projects here [at the Aero Friedrichshafen show],” Kallo said. “Three years ago, there was just one, and now there are several.”