System and method for controlling boil-off gas from liquefied hydrogen

A method for controlling boil-off gas from liquefied hydrogen, comprising:

• operating a boil-off gas controlling system that comprises:
• at least two storage tanks storing liquefied hydrogen, and
• an internal temperature maintenance device disposed inside each of the at least two storage tanks and configured to cause each storage tank to be operated in a high-temperature mode or in a low-temperature mode to induce or suppress vaporization reaction of the stored liquefied hydrogen,
• wherein the at least two storage tanks comprise a first storage tank,
• wherein operating the boil-off gas controlling system comprises operating the first storage tank in the high-temperature mode or the low-temperature mode,
• wherein operating the first storage tank in the low-temperature mode comprises maintaining at least a portion of the liquefied hydrogen stored in the first storage tank at a first temperature being a densification temperature to suppress an ortho-para conversion reaction of hydrogen, and
• wherein operating the first storage tank in the high-temperature mode comprises maintaining at least a portion of the liquefied hydrogen stored in the first storage tank at a second temperature being a temperature exceeding a triple point of the liquefied hydrogen through recovery of cold heat from the liquefied hydrogen stored in the first storage tank.