Transport refrigeration unit with vented cryogenic cooling

A method for transporting an object with a Transport Refrigeration Unit (TRU), comprising:

• providing one or more evaporators inside the TRU each containing two manifold tubes located at opposite ends of the evaporator and a multiplicity of cooling tubes traversing between the manifold tubes;
• providing one or more super-insulated vacuum tanks located in front of, beneath or inside the TRU, filled with liquid nitrogen, carbon dioxide or a cryogenic coolant connected to the one or more evaporators using vacuum-insulated pipes;
• metering a flow of nitrogen through the evaporator with a solenoid or pneumatic valve located upstream or downstream of the evaporator;
• controlling the temperature with a circuit that operates the solenoid or pneumatic valve;
• flow restricting a flow of the cryogenic coolant through the evaporator;
• venting the spent coolant outside the TRU;
• and
• distributing cooled air uniformly throughout the TRU with a multiplicity of fans, wherein at least one fan is located adjacent to and above at least one of the evaporators;
• supplying the spent coolant vented from a first compartment to a mechanism that generates and supplies energy to a multiplicity of compartments and wherein a multiplicity of insulated dividers separate the TRU into multiple compartments, each maintained at a different temperature.