Zero-emission planes hit turbulence: What do recent delays mean for net-zero aviation by 2050?

The most high-profile setback came when Airbus pushed back its ambitious goal to introduce hydrogen-powered commercial aircraft in 2035. Citing a mix of infrastructure challenges and slower-than-expected technology development, it made the announcement during the Airbus Summit 2025 and expects a 5-10-year delay. Airbus isn’t alone. Other manufacturers have recently dialed back plans or hit financial difficulties. Why this turbulence? Well, as with Airbus, the primary challenges are technology and infrastructure. 

Technologically, battery-electric aircraft remain limited to serving short routes (less than 500 km) due to severe battery weight limitations. Jet fuel is still roughly 50 times more energy dense than today’s most advanced lithium battery. While jet fuel contains about 43 MJ/kg of energy, the most advanced lithium-ion batteries today offer only around 0.9–1.0 MJ/kg, making them roughly 40 to 50 times less energy dense by weight. The additional battery weight increases the total mass the aircraft must lift and thus the energy to sustain flight—creating a compounding penalty. Hydrogen technologies such as fuel cells and combustion engines can offer greater range but face their own set of engineering hurdles, particularly concerning the need to develop lighter hydrogen storage tanks and more powerful fuel cells to minimize their significant mass and volume penalty. One of the major aircraft manufacturers, Embraer, recently pushed back its Energia project, a family of low-emission hybrid-electric aircraft, because both battery and hydrogen fuel cell advancements have been slower than hoped. This necessitated the delay of the project from its original intended entry-into-service year of 2035. 

Infrastructure is probably an even bigger barrier. Airbus noted that inadequate hydrogen infrastructure—including hydrogen production, distribution, and fueling facilities, airport expansion and modification, and new safety protocols—is one of the major roadblocks to its ZEROe program, the flagship hydrogen-powered aircraft initiative aimed at launching the world’s first commercial ZEP. Indeed, green hydrogen, which is produced using renewable electricity and water electrolysis, comprised less than 1% of global hydrogen production in 2024. And even if green hydrogen were being produced in large volumes, the infrastructure to reliably distribute hydrogen remains sparse and expensive to build. Regulatory frameworks are also lagging, and that’s creating uncertainty and slowing investment. For example, Airbus recently reduced the budget for ZEROe by 25%. 

What about the innovative startups we heard about a few years ago? Universal Hydrogen, a U.S.-based company that aimed to decarbonize regional aviation by retrofitting planes to run on hydrogen fuel cells, achieved a remarkable goal when it flew the largest aircraft ever on hydrogen-electric power. However, Universal shut down a year later after failing to secure enough funding to continue research and development. Eviation, an electric-plane startup based in Washington state, paused its Alice program and laid off most of its employees. That these firms struggled to secure the substantial funding and regulatory support necessary to scale is a lesson for the aviation industry: Zero-emission flight requires sustained and coordinated investment and collaboration beyond the reach of individual companies.  

What does this all mean for aviation’s climate targets? Well, our recent study found that even with optimistic sustainable aviation fuel (SAF) and fuel efficiency assumptions, the net-zero carbon target could be exceeded as early as 2037. Therefore, to meet the 2050 net-zero target, accelerating efforts to develop ZEPs seems critical. But with Airbus and others suggesting that 2035 is infeasible, achieving the net-zero target by 2050 looks more difficult than ever.  

This puts more pressure on SAF, technical efficiency improvements, and operational optimization to fill the gap. Due in part to this reality, hybrid-electric solutions have emerged as intermediate alternatives because they can be integrated in the medium term and offer moderate emission reductions (even though they are short of climate goals, including when combined with SAFs).  

The upcoming update to our Vision 2050 report will reflect the latest industry realities and reassess the role that ZEPs, SAFs, and other mitigation measures must play to realistically meet global targets. It will also feature an updated version of the ICCT’s net-zero aviation roadmap, which for the first time will include the climate impact of non-CO₂ emissions. 

Ultimately, stakeholders have to ask: Are hydrogen tanks getting lighter? Are fuel cells getting more powerful? Is battery chemistry improving? The recent setbacks are a wake-up call and these indicators will tell us if ZEPs can move from prototypes to actionable climate solutions. Even if there is continued progress on the technology side, the business case will need to be addressed—both the capital and regulatory aspects—to make ZEPs into a reality. In the meantime, as important as ZEPs are to the long-term solution, to stay on track for 2050 it’s likely that policymakers and the aviation industry will have to focus on alternative measures that can deliver medium-term emission savings.