Superconductivity: an emerging power-dense energy-efficient technology

As the world becomes more "electrified," efficient distribution and use of electrical power becomes increasingly important. Loss of electrical energy due to resistance to current flow translates into wasted energy and wasted economic resources. Superconductivity offers zero (dc) to near zero (ac) resistance to electrical flow; thus, the use of superconducting materials can improve the overall electrical system efficiency while significantly reducing the size and weight of power components and machinery. Although superconductivity was first discovered in 1911, the requirement of an extreme cryogenic environment (near absolute zero temperature) limited its utility. With the discovery in 1986 of a new class of "high-temperature superconductors (HTS)" that operate at substantially higher temperatures (although still cryogenic), remarkable progress has been made in advancing a broader use for superconducting technology. Full-scale demonstrations are now permitting the development of engineering skills required for systems implementation and are quantifying system benefits of this new HTS technology. This article briefly reviews some of the fundamental attributes of superconductivity and discusses how they can benefit our electrical power system. The article then briefly describes some of the ongoing U.S. demonstration projects (transmission lines, transformers, motors/generators, etc.), showing the benefits of superconductivity.