Energy consumption is continually rising in cities and conurbations. However, there is very little space left for new supply networks. High-temperature superconductor cables could be a solution here, as they require much less space than conventional electric cables and are also much more energy efficient, since they transport electricity from A to B with almost no losses. Several demonstration projects have already been successfully completed. The longest high-temperature superconductor cable installed so far covers a distance of one kilometer. A high-temperature superconductor underground cable can replace multiple parallel copper cables, reducing the need for overhead lines.
Busbars are used in industry to transport high amounts of electricity, e.g. for the industrial production of aluminum. This involves massive copper or aluminum bars, which are expensive due to the high amount of material used, difficult to install, and cause high electrical losses. Superconductor busbars are much more compact and lighter in weight and do not cause electrical losses.
Fault current limiters
High-temperature superconductors limit power spikes in public and industrial supply networks and can therefore prevent power outages caused by short circuits. Superconductor fault current limiters reduce the fault current much quicker and more efficient than conventional systems. Power spikes are limited through a physical property of the superconductors: if the amount of electricity is higher than specified, superconductors become normal conductors with high electrical resistance. This process is completely automatic, requiring no electronic control. The amount of electricity is limited as often as required, ensuring grid stability and safety. Once the electricity flow has normalized, the material gets superconducting again.
In conventional generators, copper coils weighting tons are used to generate electricity. If these are replaced by high-temperature superconductors, the weight and volume of the generator are reduced by about a third. This is because high-temperature superconductors have between 10 and 100 times higher current density than copper. This enables the use of extremely lightweight and small generators, which are especially suitable where there is little space, for example on ships or in wind turbines.