Systems and methods for cooling of superconducting power transmission lines

A cooling system, comprising:

• a coolant transmitter configured to transmit a coolant at a pressure greater than atmospheric pressure;
• an evaporation vessel at atmospheric pressure at least partially disposed in the coolant transmitter, the evaporation vessel configured to contain an amount of the coolant at a boiling point of the coolant;
• and
• a pressure reducer fluidically coupled to the coolant transmitter and the evaporation vessel,
• wherein the cooling system is configured such that heat is transferred from the coolant in the coolant transmitter to the coolant contained in the evaporation vessel.

A cooling system, comprising:

• a coolant transmitter configured to transmit a subcooled liquid at a pressure greater than atmospheric pressure, the subcooled liquid exposed to a first side of a heat exchange interface;
• an evaporation vessel at least partially disposed in the coolant transmitter;
• an exit stream conduit configured to divert a portion of the subcooled liquid from the coolant transmitter to the evaporation vessel;
• and
• a pressure regulator at a fluidic interface between the exit stream conduit and the evaporation vessel, the pressure regulator configured to maintain a pressure difference between the exit stream conduit and the evaporation vessel;
• wherein the evaporation vessel is configured to contain an amount of boiling liquid at a pressure lower than the coolant transmitter, the boiling liquid exposed to a second side of the heat exchange interface and configured to absorb heat from the subcooled liquid.