The aviation industry is responsible for around 2.5% of global CO₂ emissions, making it a significant contributor to climate change. With mounting pressure to reduce this environmental impact, hydrogen-powered aircraft have emerged as a promising alternative to conventional jet fuel. But when can we expect to see these planes flying commercially? Let’s explore the technological, environmental, and logistical factors shaping the future of hydrogen-powered aviation.

Hydrogen-powered aircraft: how do they work ?

Hydrogen-powered aircraft typically rely on one of two primary methods for propulsion:

• Hydrogen fuel cells: These work by converting hydrogen into electricity to power electric motors. Fuel cells combine hydrogen with oxygen in an electrochemical process, producing electricity with only water as a byproduct. This process is completely emission-free at the point of use, making it an attractive solution for a greener future in aviation. (See Hydrogen Fuel Cell on Wikipedia)

• Hydrogen combustion engines: In this scenario, hydrogen is burned directly in modified jet engines, similar to traditional aviation fuel. However, hydrogen burns more cleanly, producing fewer carbon emissions compared to kerosene. (See Hydrogen combustion engine on Wikipedia)

Despite the clear environmental benefits, implementing these technologies at scale is complex, which brings us to the next question—when will we see hydrogen planes in the skies?

The technological hurdles

Transitioning to hydrogen as a fuel source presents several technical challenges that need to be addressed before hydrogen-powered aircraft can become commercially viable.

1. Energy density: While hydrogen has a higher energy content per kilogram than traditional jet fuel, it is far less dense by volume. This means that hydrogen must be stored in large tanks, which may affect aircraft design and payload capacity. Engineers are currently exploring how to optimize the shape, material, and placement of hydrogen tanks on aircraft. (See Hydrogen energy density on Wikipedia)

2. Cryogenic storage: Hydrogen must be stored at extremely low temperatures (below -253°C) to remain in liquid form, which is necessary for practical use in aviation. Developing reliable and safe cryogenic tanks is one of the key technical obstacles. (See Cryogenic liquid hydrogen on Wikipedia)

3. Refueling infrastructure: Airports will need a complete overhaul of their current fuel supply systems to accommodate hydrogen refueling stations. This infrastructure is currently limited to a few research and experimental facilities, and a global rollout will require significant investment and coordination. (See Hydrogen infrastructure on Wikipedia)

When will hydrogen-powered aircraft be available ?

While hydrogen-powered aircraft are not commercially available yet, several prototypes are already in development, and timelines are becoming clearer. Based on current projections, here are some key milestones:

• Short-haul hydrogen aircraft: Airbus, a major player in the industry, has committed to bringing a hydrogen-powered aircraft to market by 2035. This initial rollout is expected to focus on short- and medium-haul flights (under 2,000 km), where hydrogen technology is most feasible in the near term. (See Airbus Zero-Emission Concept on Wikipedia)

• Long-haul flights: Due to the storage challenges of hydrogen, long-haul flights may take longer to adopt hydrogen propulsion systems. Some experts predict this may not happen until after 2050, depending on breakthroughs in hydrogen storage and aircraft design.

• Experimental flights: Companies like ZeroAvia and Universal Hydrogen are already testing smaller hydrogen-powered planes. ZeroAvia recently conducted successful test flights with a hydrogen fuel cell-powered aircraft, and the company is aiming to certify its first commercial aircraft by 2025. These early experiments are crucial for proving the viability of hydrogen in commercial aviation. (See ZeroAvia on Wikipedia)

Environmental impact: Is hydrogen the answer ?

Hydrogen offers a major advantage over fossil fuels because it produces zero carbon emissions when used in fuel cells or in combustion engines with minimal emissions. But is it the ultimate solution for a sustainable future in aviation?

While hydrogen eliminates CO₂ emissions, it’s important to note that most hydrogen today is produced through a process called steam methane reforming, which involves natural gas and generates significant carbon emissions. (See Steam reforming on Wikipedia)

However, green hydrogen, produced via electrolysis (using renewable energy to split water into hydrogen and oxygen), could eventually solve this issue. Scaling up green hydrogen production is essential for hydrogen-powered aircraft to fulfill their promise of zero-emission travel. (See Green hydrogen on Wikipedia)

The path to commercialization

Aviation regulators, airlines, and governments are gradually aligning to make hydrogen-powered aircraft a reality, but this process requires coordinated global efforts.

• Government support: National governments, particularly in Europe and the US, are increasingly setting targets for hydrogen adoption in aviation. For example, the European Commission’s Clean Hydrogen Alliance is pushing for large-scale hydrogen adoption across various sectors, including aviation. (See Clean Hydrogen Alliance on Wikipedia)

• Investment in infrastructure: Developing hydrogen storage, refueling, and production capabilities on a global scale will require enormous investment. This will likely come from both the public and private sectors, as the aviation industry cannot bear the costs alone. Additionally, existing airports will need to be retrofitted with hydrogen refueling facilities to support future fleets.

• Airline initiatives: Several airlines have announced plans to transition part of their fleet to hydrogen. EasyJet, for example, has partnered with Wright Electric to develop hydrogen-powered planes for its short-haul routes by the 2030s. (See Wright Electric on Wikipedia)

When can we fly on hydrogen planes ?

The journey toward hydrogen-powered aircraft is progressing rapidly, but it will be some time before these planes become a standard part of commercial aviation. Early adopters can expect to see short-haul hydrogen flights by the mid-2030s, with long-haul hydrogen planes coming later, likely post-2050. In the meantime, advancements in both hydrogen production and storage technologies will be crucial in determining how quickly this vision becomes a reality.

While hydrogen isn’t the only answer to decarbonizing aviation, it plays a vital role in achieving the goal of zero-emission flights. Continued innovation, investment, and international cooperation will be necessary to ensure hydrogen-powered aircraft soar above the clouds sooner rather than later.