Progress with superconductors

Superconductors are materials which have zero resistance and can therefore carry high currents with no energy loss due to heating. At present such materials only superconduct at low temperatures requiring cooling.

This is a quote from a report about the progress being made to use such materials in electrical generators as used in power stations. Any small increase in efficiency saves a lot of energy and money. There are references to several Physics concepts including electrical power and efficiency, temperature, heating, centrifugal force as well as superconductivity. Although not yet in the syllabus the term "superconductivity" is becoming important enough that any educated citizen should know what it means.

"The experts from Corporate Technology — the central research organization at Siemens — have acquired a great deal of experience with regard to electric motors and generators whose coils are made from high-temperature superconductors. These superconductors have an operating temperature of around minus 240 degrees Celsius. The electric current density possible with such windings is approximately 30 to 100 times greater than the values achievable with copper coils at room temperature. Following tests on a 400-kilowatt model motor, a four-megawatt (MW) generator operating at 3,600 rpm was subjected to a program of long-term tests. This was followed by tests on a 4 MW high-torque motor at 120 rpm. Each of these projects showed that the high-temperature superconductor technology halved the machines’ losses while also reducing their size and weight. "