Thermal management in space is a big issue. The ISS has big radiators on the long truss, and lots of plumbing for cooling. For a superconducting magnetic shiel

Thermal management in space is a big issue. The ISS has big radiators on the long truss, and lots of plumbing for cooling. For a superconducting magnetic shield, it depends how much power is used to maintain it. MgB2 supports high currents compared to cuprates, so I guess once it's turned on it doesn't need much?