The Three Mile Island Trade

Key Takeaways

• Microsoft signed 20‑year PPA for Three Mile Island, targeting 2028.
• PJM grid delays push expected connection to 2031, adding risk.
• Constellation’s stock rose 57% in 2025, fell ~20% in 2026.
• Hyperscalers capture baseload power, shifting costs to residential ratepayers.
• Nuclear‑AI deals illustrate emerging risk‑transfer model in U.S. energy market.

Pulse Analysis

The revival of Three Mile Island reflects a broader shift where AI‑driven hyperscalers are financing legacy nuclear assets to secure carbon‑free baseload. While the $1.6 billion investment promises a steady supply for machine‑learning workloads, the project must navigate a maze of NRC approvals, turbine refurbishments, and grid‑capacity constraints. PJM’s revised interconnection date of 2031 underscores how physical and regulatory timelines often outpace commercial contracts, creating a hidden risk buffer that utilities like Constellation must absorb.

Financial markets initially cheered the deal, propelling Constellation’s shares up 57% in 2025 as investors priced in the perceived upside of a nuclear renaissance. However, the subsequent 20% pullback in 2026 reveals a correction as investors recognize that the utility bears construction overruns, safety inspections, and potential revenue shortfalls if the plant misses its target. This risk transfer model—where tech firms lock in price but leave execution risk to power producers—mirrors similar structures in renewable PPAs but is amplified by nuclear’s longer lead times and higher capital intensity.

Beyond the balance sheet, the arrangement raises systemic questions for the American grid. By diverting a sizable chunk of baseload capacity to private contracts, residential ratepayers may shoulder higher costs to fund infrastructure that no longer serves the public pool. Moreover, the rapid influx of hyperscaler‑backed nuclear projects could crowd out future investments in new reactors, SMRs, or renewable upgrades, potentially limiting the nation’s overall decarbonization pathway. Policymakers and regulators will need to address these dynamics to ensure that the pursuit of AI‑grade energy does not compromise grid reliability or equitable pricing.