 The European grid consists mainly of shorter transmission circuits, which are less vulnerable to damage.The (nearly direct) currents induced in these lines from geomagnetic storms are harmful to electrical transmission equipment, especially transformers—inducing core saturation, constraining their performance (as well as tripping various safety devices), and causing coils and cores to heat up.In extreme cases, this heat can disable or destroy them, even inducing a chain reaction that can overload transformers.