Advances in materials and manufacturing process are yielding the second generation of high-temperature superconducting materials. These so-called 2G materials are now making their grid-connected debut in New York. As reported in the Physics Today article by Jeremy N. A. Matthews, “Next-generation high-Tc superconducting wires debut in the power grid”, a new material called YBCO (YBa2Cu3O7–x) has emerged to replace first-generation BSCCO (Bi2Sr2Ca2Cu3O10-x) high-temperature superconducting cable. YBCO has several advantages over BSCCO including increased energy carrying capacity (106 A/cm2 versus 104 A/cm2 for BSCCO) and reduced dependence on expensive silver sheathing.
In addition to its higher capacity and economic advantages, 2G cable has an inherent security feature. Above a critical current, 2G YBCO wire transitions from being a superconductor to a resistor. This feature enables passive suppression of power surges that can cause current faults in the grid. This novel attribute has attracted funding from the Department of Homeland Security for live, utility-scale testing of YBCO wires, and the intrinsic safety of 2G wire may elevate superconducting cable from a niche curiosity to a mainstay component of the US electricity grid. By strategically replacing power lines with 2G cable, grid failures resulting from current surges could be mitigated.
For more information on the evolution of superconductors for the power grid, please check out my previous blog posts, “SuperGrid Could Transport Electricity and Hydrogen in Parallel” and “Superpower’s 2-G Superconducting Cable Slated For Grid Installation”.