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Advancing Hydrogen Flight
It is a truth universally acknowledged that delivering hydrogen fuel to airport locations is one of the big challenges that might slow the aviation transition. ZeroAvia intends to get the ball rolling by ensuring the solutions are ready for our first operators flying passengers and cargo, with plans to be in the air within two years.
Meet our first-of-a-kind hydrogen refueling and dispensing truck, developed at our Cotswold Airport R&D facility in the UK.
For many early adopting airlines, they will be at the vanguard of a new era of flight, but clean hydrogen production will also be in its infancy still – meandering down the cost curve and with airport infrastructure yet to be in place. We need to get affordable hydrogen to the first airport sites from a handful of production locations. To maintain favorable economics, any vehicle bringing that hydrogen to the airport needs to minimize the number of trips by maximizing the amount of hydrogen it can deliver per refuel.
No practical vehicle exists today with these capabilities, so we have gone ahead and designed and built one!
ZeroAvia’s Gaseous H2 Mobile Storage & Dispensing (GMSD) truck has been designed to maximize the amount of useable hydrogen fuel stored and increase the number of aircraft refuels possible thanks to some unique innovations.
The 40ft truck is capable of carrying around 780kg of gaseous hydrogen stored at 500 bar, split across six banks of 12 composite cylinders (72 gaseous hydrogen tanks). The system includes an integrated onboard compressor, which affords it a wide hydrogen filling pressure range of between 20 bar and 500 bar. When filled, GMSD operates via a cascade fill architecture, enabling a substantial increase in usable hydrogen capacity and a reduction in refill trips.
The refueler will demonstrate the viability of hydrogen refueling at airports and support regulatory and operational understanding of the safety case for GH2.
ZeroAvia’s custom-designed hydrogen refueling truck stores gas at pressures of up to 500 bar, enabling an effective pressure differential for transfer into aircraft tanks operating at 350 bar. During refueling, hydrogen flows from the truck’s storage system to the aircraft via this gradient, ceasing once pressure equilibrium is reached between the dispensing system and the aircraft. The truck’s storage is divided into multiple banks, and hydrogen is delivered sequentially—from the lowest-pressure bank upward—following a cascade refilling process. This method inherently leaves a residual volume of low-pressure hydrogen in each cylinder, which cannot be transferred once equilibrium is achieved. To address this, ZeroAvia’s truck incorporates an onboard compressor that actively re-pressurizes and consolidates the remaining hydrogen into the highest-pressure bank, thereby maximizing the usable supply and extending the effective refueling capacity.
The truck provides early adopting airline customers with a source of flexible and readily available hydrogen and has been designed to meet industry standards of operation and safety in an airport environment. ADR certification allows for transport of hydrogen on public roads in the UK and Europe. Importantly, the truck will provide a parity in refueling time compared to existing fuel alternatives, enabling hydrogen aircraft to match the turnaround time of fossil fuel predecessors.
ZeroAvia’s mobile gaseous hydrogen refueling truck can support hydrogen aircraft operations by providing readily available hydrogen, of the right quality, and stored at the right pressure in large quantities. The refueler design overcomes a number of the infrastructure and logistical challenges, and ZeroAvia is already working through a variety of demonstration cases. The GMSD operates with proven refueling protocols for gaseous hydrogen, but the unique combination of features for optimizing usable hydrogen will aid in the drive towards aviation adoption.
GH2 refueling solutions are key to getting the first hydrogen aircraft flying, but liquid hydrogen is necessary for large aircraft that are moving the bulk of passengers and cargo. ZeroAvia is already in the process of designing and testing a mobile liquid hydrogen refueling system and we’ll share more on this system in due course.
We are taking the first steps to build the hydrogen supply chain of the future to ensure our early customers have access to fuel. We are also working with airports, innovative energy companies and other players to drive the transition at large.
