Superconductivity for hydrogen economy

The emerging hydrogen economy is expected to deal with a large amount of liquid hydrogen produced from the renewable energy resources. The main advantage of liquid hydrogen in comparison with other forms of its storage and transportation is in allowing wide use of superconductivity, which would optimise energy efficiency of the economy. The basic element of the infrastructure for hydrogen economy is a network of superconducting pipelines carrying simultaneously liquid hydrogen and loss-free electricity. The most likely material for such infrastructure is MgB₂, the only superconductor efficiently working at boiling temperature of liquid hydrogen and not showing strong critical current reduction on grain boundaries. The cheap techniques for the preparation of MgB₂ are hot isostatic pressing, resistive sintering and paint coating. These and other advanced techniques are able to provide MgB₂ with suitable for the infrastructure structural and superconducting properties. The preparation of a large-area superconducting joint between two pieces of MgB₂ as a technique enabling this infrastructure is reported. A potential of synergy between liquid hydrogen and superconductivity is revealed in a range of possible new energy applications.