Superconducting power cables
Near zero resistance
Wherever electric current flows, there is electrical resistance. That’s why part of the energy is lost along the way from the power plant to the electrical socket. But that resistance vanishes in some materials at very low temperatures – they become superconductors and let current flow almost entirely unimpeded. Superconducting cables are cooled with liquid nitrogen. When vaporized below atmospheric pressure, the gas can reach a temperature of minus 209 degrees Celsius. That compensates for the heat that the superconducting cable absorbs from its surroundings. A return system provides for an energy-efficient closed circuit.