A cryogenic hydrogen storage system reduces hydrogen loss by providing an initial supply of hydrogen wherein the initial hydrogen has an initial para/ortho hydrogen ratio. The initial hydrogen having an initial para/ortho hydrogen ratio is adjusted to produce final hydrogen having a final para/ortho hydrogen ratio with a greater amount of ortho hydrogen. The cryogenic hydrogen storage system is refueled with the final hydrogen having a final para/ortho hydrogen ratio with a greater amount of ortho hydrogen.
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