Vehicle refueling with liquid hydrogen thermal compression

We have modeled an approach for dispensing pressurized hydrogen to 350 and/or 700 bar vehicle vessels. Instead of relying on compressors, this concept stores liquid hydrogen in cryogenic pressure vessels where pressurization occurs through heat transfer, reducing the station energy footprint from 12 kW h/kgH2 of energy from the US grid mix to 1.5–2 kW h/kgH2 of heating. This thermal compression station presents capital cost and reliability advantages by avoiding the expense and maintenance of high-pressure hydrogen compressors, at the detriment of some evaporative losses. The total installed capital cost for a 475 kg/day thermal compression hydrogen refueling station is estimated at about $611,500, an almost 60% cost reduction over today's refueling station cost. The cost for 700 bar dispensing is $5.23/kg H2 for a conventional station vs. $5.45/kg H2 for a thermal compression station. If there is a demand for 350 bar H2 in addition to 700 bar dispensing, the cost of dispensing from a thermal compression station drops to $4.81/kg H2, which is similar to the cost of a conventional station that dispenses 350 bar H2 only. Thermal compression also offers capacity flexibility (wide range of pressure, temperature, and station demand) that makes it appealing for early market applications.

► Thermal compression design dispenses H2 to 350 and/or 700 bar vehicles. ► Instead of using compressors, LH2 is pressurized by heating. ► Concept shows cost and reliability advantages, at the expense of evaporative losses. ► Thermal compression particularly suited for early market scenarios.