Room-Temperature Superconducting Power Line SuperLink Goes Live in China: Transmission Losses Drop From 5% to 0.01%

State Grid Corporation of China announced on May 1 that its 800km ultra-high voltage transmission line from Jiuquan, Gansu to Changsha, Hunan has completed full-line integration of room-temperature superconducting cable segments and entered commercial operation. Named SuperLink, the line uses copper-oxide room-temperature superconducting material in a critical 200-kilometer segment, reducing transmission losses from approximately 5% for traditional copper conductors to 0.01% — a 500-fold reduction.

SuperLink's technical foundation is the copper-oxide room-temperature superconductor breakthrough achieved by the Chinese Academy of Sciences Institute of Physics team in late 2028. The material achieves zero resistance at 15°C under normal pressure — while not truly "room temperature ambient pressure" (requiring mild cooling to maintain 15°C), it has eliminated the liquid nitrogen or liquid helium cooling requirements of earlier superconductors. Team leader Academician Zhao Zhongxian said at the commissioning ceremony: "From the discovery of superconductivity in 1911 to actual use in power transmission lines today, humanity has walked one hundred and eighteen years."

The Economic Equation

SuperLink's economics require careful calculation. Superconducting cable itself costs approximately 12 times traditional cable, but due to negligible losses, the 800km line saves approximately 470 million kWh annually — translating to about 330 million RMB in electricity cost savings. Combined with eliminated intermediate substations (traditional UHV transmission requires substations every 200km), infrastructure costs are partially offset. State Grid's Economic Research Institute assessment concluded SuperLink's total lifecycle (30-year) comprehensive cost is approximately 18% lower than traditional solutions.

But large-scale superconducting cable deployment faces material supply bottlenecks. Copper-oxide superconductor fabrication requires high-purity rare earth oxides, with current global annual production sufficient for only about 500km of superconducting cable. State Grid plans to expand superconducting transmission to 3,000km by 2030, but achieving this depends on rare earth supply chain expansion.

Global Impact

SuperLink's commissioning has drawn widespread attention from the international power industry. India's Power Minister Raj Kumar Singh expressed interest in introducing superconducting technology on the Delhi-Mumbai transmission line after visiting China. The European Commission's Directorate-General for Energy issued a statement urging Europe to accelerate superconducting transmission R&D investment to avoid falling behind in next-generation grid infrastructure.

However, the US Department of Energy has expressed concern about SuperLink's technological independence. The core fabrication process for copper-oxide superconductors is held by the Chinese team, and the US currently lacks mass production capability. Energy Secretary Jennifer Granholm told Congress the US needs to build "an independent and competitive supply chain" in superconducting materials.