Cryogenic fuel system with auxiliary power provided by boil-off gas

A method for providing auxiliary power, the method comprising:

• determining a mode of operation at which a vehicle system is operating;
• determining an auxiliary energy level;
• determining an available boil-off auxiliary energy level that is available from a boil-off gas stream from a cryotank configured to hold a cryogenic fluid;
• and
• operating a boil-off auxiliary power unit based on the mode of operation, the auxiliary energy level, and the available boil-off auxiliary energy level, wherein the boil-off auxiliary power unit is configured to utilize the boil-off gas stream to provide energy to one or more auxiliary components of the vehicle system.

A tangible and non-transitory computer readable medium comprising one or more computer software modules configured to direct at least one processor to:

• determine a mode of operation at which a vehicle system is operating;
• determine an auxiliary energy level;
• determine an available boil-off auxiliary energy level that is available from a boil-off gas stream from a cryotank configured to hold a cryogenic fluid;
• and
• operate a boil-off auxiliary power unit based on the mode of operation, the auxiliary energy level, and the available boil-off auxiliary energy level, wherein the boil-off auxiliary power unit is configured to utilize the boil-off gas stream to provide energy to one or more auxiliary components of the vehicle system.