Innovative Approaches to Minimize Boil-off Losses from Liquid Hydrogen Storage Systems

b. Innovative Approaches to Minimize Boil-off Losses from Liquid Hydrogen Storage Systems This subtopic solicits proposals for novel concepts, ranging from component level to system scale, that substantially mitigate, recapture, or beneficially use boil-off from either bulk stationary storage of liquid hydrogen, transfers of liquid hydrogen, or liquid hydrogen storage systems onboard transportation vessels, such that boil off is less than 0.1%. Examples include but are not limited to development of novel materials and components that manage heat transfer from liquid equipment, concepts to capture and recover boil-off vapor, and innovative integration of station components (e.g., cryo-pumps and liquid dewars). Hydrogen is transported and stored in liquid form in applications where demand is significant and stable, but where overall regional hydrogen demand is not large enough to warrant the use of pipelines. Sectors that use liquid hydrogen include space applications, industrial facilities (e.g. metal processing plants), and fueling stations for hydrogen vehicles and material handling equipment. Given the exceptionally low boiling point of liquid hydrogen (20 K), boil-off losses throughout the delivery pathway, which includes trucking, offloading to a facility, storage and use of the liquid hydrogen at the facility, can be a substantial cost contributor. Mitigation of these boil-off losses will become increasingly important as newer applications for liquid hydrogen emerge, e.g. in heavy-duty transportation, marine vessels, and rail vessels where hydrogen may be stored onboard in liquid form. These applications will require a wide range of onboard liquid hydrogen storage capacities, from around 60 kg for long-haul Class 8 trucks, to thousands of kgs for larger marine vessels. Boil-off losses in these use cases are intimately tied to dormancy and duty cycles and could be just as significant as those present in refueling stations. Strategies to eliminate the boil-off of fuels in general have been explored in many other industries to date, including the aerospace and liquefied natural gas (LNG) sectors. Approaches that have been studied include innovative methods of insulation, mixing of layers within liquid dewars to prevent stratification, use of cryo-coolers, recovery of boil-off to power ancillary equipment, and sophisticated cryo-pump designs. Many of these approaches are capital-intensive, which prohibits their widespread use and would hinder any ability to achieve HFTO's hydrogen cost targets. Phase I of the effort is expected to involve an in-depth analysis that includes a preliminary design of the selected component(s) or strategy, as well as specific research, development, and (if reasonable within the Phase I budget) proof-of-concept testing of any new components or processes to show that they have the potential to be incorporated into a liquid hydrogen storage system. Phase II should focus on prototype development and testing at a scale relevant to demonstrate the viability of the concept for the specific application or use case being targeted. Identification of commercialization strategies and a market analysis should also be included. Identification of potential commercialization partners, with indication of commitment, would greatly strengthen Phase II proposals. Questions Contact: Zeric Hulvey, Zeric.Hulvey@ee.doe.gov