历史上，1979 年3月28日凌晨4点00分36秒，Three Mile Island 一号机在仅营运三个月后发生部分熔毁并引发全球关注。事件未立即造成人命损失，但即刻摧毁公众信任：九年内取消 67 座规划设施，且美国反应炉数量于1990年达到 112 个高峰，远低于 AEC 时代曾预估 2000 年 1000 个。重启规划中，营运者必须证明老旧设备仍符合安全标准，其中关键为两台 550 吨蒸汽发生器，最终通过检验；该批在2009年曾以约 6 亿美元更换。2024 年又新增替换3 台 250 吨变压器，花费约 1 亿美元。
监管与训练工作由 Craig Smith 等人主导，反映停机至重启期仍保留「1/100」风险保守观。部分既有机组在修复的同时，产业仍押注新技术。投资者支持 SMR 与融合能源计划，但多数仍停留在研发前段且受 NRC 审查限制，Oklo 事件即为例证。Biden 提出到2050年将核电厂数量扩至三倍，特朗普则主张四倍并在2030年前有 10 座大型机组在建，但燃料链限制仍在，包括仍高度依赖进口浓缩铀。安全指标仍是核心论据：每太瓦时死亡率约为煤炭25、天然气3、核电低于1，而 Microsoft 与 Nvidia 估计生成式 AI 可使许可文件流程加速超过90%。
On May 8, 2026, Bloomberg reports a simulator drill at Three Mile Island, where operators practiced 1960s-era control-room procedures before a restart. The Susquehanna site is expected to return as the Crane Clean Energy Center by mid-2027. A September 2024 Microsoft–Constellation Energy contract requires Microsoft to buy all power from the single remaining operating unit, 835 MW, for 20 years. That power is explicitly directed to AI workloads. The report also lists Google’s 25-year deal for Iowa’s Duane Arnold plant, nuclear procurement deals from Meta and Amazon, and Palisades’ planned 2026 restart, showing AI demand as a central driver of the U.S. nuclear revival.
Historically, at 4:00:36 a.m. on March 28, 1979, a unit at Three Mile Island partially melted down after only three months of operation, triggering global scrutiny. The event caused no immediate deaths but immediately shattered public trust: 67 planned facilities were canceled within nine years, and U.S. reactor counts peaked at 112 in 1990, far below the AEC-era forecast of 1,000 by 2000. In restart planning, operators had to prove legacy equipment still met safety standards, with two 550-ton steam generators as a key checkpoint; they ultimately passed. Those units had been replaced in 2009 for about $600 million. In 2024, three 250-ton transformers were additionally replaced at about $100 million.
Regulatory and training work is led by people including Craig Smith, reflecting a cautious one-in-100 risk mindset in the shutdown-to-restart phase. While part of existing plants is being repaired, the industry still bets on new technology. Investors support SMRs and fusion, but many remain precommercial and constrained by NRC review, with the Oklo case as an example. Biden proposes tripling the number of U.S. nuclear plants by 2050; Trump argues for a quadruple increase and ten large units under construction by 2030. Yet fuel-chain limits persist, including continued heavy dependence on imported enriched uranium. Safety metrics remain a core argument: deaths per terawatt-hour are about 25 for coal, 3 for natural gas, and below 1 for nuclear, while Microsoft and Nvidia estimate generative AI can accelerate permitting paperwork by over 90%.