Hydrogen and its Role in the Future of Sustainable Commercial Aviation 

Recently, I had the chance to watch the Blue Angels from I-5. The show was definitely breathtaking, but the spectatorship was perhaps more absurd. Cars slowed to watch the jets whiz past their heads. People lined the bridges to watch the military planes do acrobatic tricks. Lake Washington, which usually only has two or three boats in it, was filled with hundreds of boats carrying those watching the show from the water. But when the traffic cleared, the people left, and the lake returned to normal, one thing remained in the air: smoke. 

According to the San Francisco Chronicle, the show jets emit around 825,600 lbs. of CO2 in a show week, equivalent to the amount burned driving from San Francisco to Atlanta 375 times in an average car.  

Despite its unmistakably large environmental impact, the aviation industry as a whole is one of the hardest industries to fully decarbonize. Although several present efforts focus on SAF (Sustainable Aviation Fuel) as a commercially viable alternative, these substitutes do not eliminate carbon emissions. On June 9, 2026, experts at the 5th annual H2-Aero Symposium shared the latest advances in a new sustainable solution: hydrogen aviation. 

In hydrogen aviation, aircraft are powered primarily in one of two ways: fuel cells or gas turbines. In a fuel cell, pure hydrogen gas reacts with oxygen from the air to produce electricity used to power the aircraft, while water and heat are the sole byproducts. As this method results in a complete redesign of the aircraft engines, it is currently only used to power small aircraft. Among the many challenges this redesign brings is the need for extensive Balance of Plant (BoP) systems to maintain optimal operating conditions (e.g, temperature, air pressure). This requirement causes two main problems. First, it occupies additional weight and space that ideally should be occupied by passengers and cargo. Second, these systems consume energy, which decreases the power available for the aircraft, and results in efficiency loss. Companies at the symposium, notably ZeroAvia, are currently developing solutions to these limitations. Specifically, ZeroAvia’s ZA2000 engine uses HTPEMs (High Temperature Proton Exchange Membranes) to decrease the need for sophisticated BoP systems, thereby increasing energy density and efficiency.  

Meanwhile, other companies, particularly Airbus and Rolls-Royce, are pursuing a different approach. As hydrogen is flammable, it can be used to fuel the traditional gas turbine engines used today. This will inevitably require modifications to the engines, including an optimized combustion chamber, fuel injectors to convert liquid hydrogen to gas, and different control systems. Nevertheless, there are many disadvantages to this approach, the foremost of which concerns the storage of hydrogen.  

Hydrogen gas has low energy density. For this reason, many companies store it as liquid hydrogen instead. However, to achieve a liquid state, hydrogen must be stored at -253o C. Consequently, storage tanks require the integration of auxiliary cooling systems, which occupy weight and space. This makes the traditional method of storing fuel in the space-constrained wings unviable, prompting several companies to develop alternative storage solutions. For example, a proposal from UK’s Aerospace Technology institute stores fuel and auxiliary systems at the back of the plane. To balance the weight, additional wings, known as canards, are installed in the front of the plane. Even so, the use of canards presents stability issues and aerodynamic complications that must be resolved. 

Despite these challenges, we at EcoAero believe that hydrogen’s versatility gives it the potential to be a technically viable clean aviation fuel. However, the development of the necessary infrastructure is the main hindrance to larger-scale adoption. For hydrogen to be commercially viable, airports must develop adequate hydrogen refueling and storage systems which will take time and money. 

Even if airports respond to a hydrogen revolution, another aspect of sustainable hydrogen aviation is the ability to commercially produce clean hydrogen. Today, most hydrogen produced is grey hydrogen, meaning it comes from “natural gas fixing”, a process that releases CO2. Despite their varying technical challenges, both gas turbines and fuel cells rely on hydrogen fuel to reduce their carbon emissions. Even if all the technical challenges presented are resolved, we will not truly have a clean aviation industry if hydrogen is produced in greenhouse-gas-emitting settings. Thus, a way to commercially produce sustainably sourced hydrogen is what will ultimately ensure that hydrogen aviation is the panacea to green aviation future.  

Image sourced via Civil Aviation Authority. Used for editorial purposes only. No commercial use. All rights belong to their respective owners.