Conceptual Design of a SuperConducting Energy Pipeline for LH2 and Power Transmission Over Long Distances

The design of a single-pole MgB
₂
superconducting hydrogen-cooled cable for DC current transmission at low voltage (10 kV) is presented here. The cable consists of a former made of MgB
₂
superconducting wires, a dielectric layer and an annular region that allows for the passage of hydrogen at inlet pressures above the critical one. The cable is contained within a corrugated cryostat, insulated from the external environment. The use of MgB
₂
as a superconducting material allows for the operation of the cable in the range 15–27 K, which reduces the cooling requirements and increases the efficiency of the system. The hydrogen-cooled annular region, acting as a pipeline for the cryogen transport, allows at the same time the efficient cooling of the cable, while the corrugated cryostat provides additional insulation and structural support, together with a relief volume in the case of an accident. The results of this study, mainly performed with a simplified model, benchmarked against the OPENSC
²
software, show that the cable is able to support DC current transmission at 10 kV, with maximum cable lengths of several tens of km for inner diameters of the cryostat >120 mm, supporting a H
₂
mass flow rate >1 kg/s. Overall, this study demonstrates the feasibility of combining the DC current transmission at low-medium voltage by MgB
₂
to the transport of liquid hydrogen, providing at the same time instantaneous storage of chemical power.