Design of a SuperConducting Energy Pipeline in MgB2 for the simultaneous transport of liquid hydrogen and electric power over long distances

It is here presented the design of a MgB2 superconducting hydrogen-cooled cable for DC current transmission at low voltage (10 kV). The cable consists of a former made of MgB2 superconducting wires, a dielectric layer and an annular region that allows for the passage of hydrogen at pressures above the critical pressure. The cable is contained within a corrugated cryostat, insulated from the external environment. The use of MgB2 as a superconducting material allows for the operation of the cable at 15-20K, 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, and a relief volume in the case of an accident. The results of this study, mainly performed with a simplified model, benchmarked against the OPENSC2 software, show that the cable is able to support DC current transmission 10 kV, with maximum cable lengths of several tens of km for inner diameters of the cryostat of ~200 mm, supporting a H2 mass flow up to 2 kg/s. A preliminary techno-economic characterization is also performed. Overall, this study demonstrates the feasibility of combining the DC current transmission at low voltage by MgB2 to the transport of liquid hydrogen. Future research will focus on the optimization of the cable design and the development of fabrication methods and to design the auxiliary systems.