Superconducting power and transport system

A system comprising:

• a tube infrastructure that includes one or more tubular structures disposed along a path;
• a transport subsystem, disposed within the tube infrastructure, that includes a magnetic levitation mechanism for supporting and moving one or more magnetic levitation cars within at least one of the one or more tubular structures;
• and
• an electric power distribution subsystem, disposed within the tube infrastructure, that distributes electrical power to locations along the path, and that also provides power to the transport subsystem's magnetic levitation mechanism, the electric power distribution subsystem including one or more electrical transmission lines;
• wherein the tube infrastructure is shared between the transport subsystem and the electric power distribution subsystem,
• wherein the one or more cars have an active seal system of seal structures disposed on the outside thereof such that each of the seal structures is not in contact with a wall of the tubular structure when an interior of the seal structure is at less than a local ambient air pressure, each of the seal structures is in contact with the wall of the tubular structure when the interior of the seal structure is at the local ambient air pressure, and each of the seal structures is in closer compliant contact with the wall of the tubular structure when the seal interior is above ambient air pressure.