Liquid Hydrogen Refueler for Hydrogen-Electric Aircraft Applications
ZeroAvia
Recipient
Hollister, CA
Recipient Location
$642,642
Amount Spent
Active
Project Status
Project Update
The project team completed a hazard and operability (HAZOP) study for the LHMSD system in July 2024. Findings from the HAZOP are being incorporated into ongoing work to lock the process and instrumentation diagram and the front-end engineering design documents for the mobile refueler, zero boil-off system, and LH2 tank to a third-party systems integrator. After the system is built and passes factory/site acceptance tests, it will be commissioned at a code-compliant site.
The Issue
Present liquid hydrogen (LH2) refuelers suffer from several technological deficiencies, the most significant of which is boiloff-gas venting. During a warm fill for an LH2 tank, the LH2 flashes into gaseous hydrogen. Also, since LH2 is stored at very cold temperatures (20K or -423F) there is constant environmental heat ingress from surroundings that causes the stored liquid hydrogen to flash and boil-off, which is generally cold, dense gaseous hydrogen that vents into atmosphere. In addition to being wasteful, this is a process that presents a combustion hazard since it settles down to the ground before warming and rising. Fugitive hydrogen also has second-order greenhouse gas effects. This proposed project seeks to address this challenge and several more through innovative approaches and design.
Project Innovation
Only LH2 has the gravimetric energy density required to fuel zero-emission flight, however handling -423 ºF liquid in the first-ever civilian application requires the full system and several of its components to be pulled forward through several TRL levels. The full system integration into a vehicle that meets highest safety and airside certification standards has never been done before. Subsystems such as state-of-the-art insulated LH2 tanks will be integrated with zero boil-off technologies. LH2 pumps will be able to achieve high flow rates and therefore low fill times for large-capacity aircraft tanks. Finally, system safety for practical ground operations must be paramount and therefore highly automated (control system & HMI panels) as well as fail-safe (redundant sources of on-board power: fuel cell and battery/inverter).
Project Goals
Project Benefits
By unlocking hydrogen aviation in California, ZeroAvia projects a pull-through in terms of H2 demand ramping to 66 tons per day by 2032 across the State of California from just 10 regional airports. This firm demand will help lower the cost of hydrogen and reduce emissions in the communities surrounding the airports. In the future, the LHMSD could also help decarbonize ports and other locations where LH2 fuel is in demand.
Consumer Appeal
The LHMSD offers reduced cost by reducing the operational costs of LH2 when compared to existing systems. This can be achieved by limiting the wastage due to boil off in traditional systems. Additionally, the LMHSD is automated, reducing the personnel time required to operate the system. Mobility and <0.05% boil off are key elements desired by a wide array of industries including aviation and this product will fit within these.
Environmental Sustainability
The LHMSD offers a zero-boiloff storage system (highly integrated insulation system in addition to cryocooler), a fast flow rate umbilical used for filling vehicles, and a safe, automated control system to unlock the use of LH2 to reduce emissions from difficult-to-electrify transportation end-uses.
Key Project Members
Gurjap Singh
Subrecipients
Match Partners
