Shares of Constellation Energy rocketed 13.2% to $303.01 Tuesday after the company disclosed what may be the largest single corporate power deal in U.S. history. Google contracted for 3,590 megawatts of power from Constellation in PJM, the nation's largest grid, with new nuclear energy accounting for about a quarter of that supply. The announcement caps a stunning week: just days earlier, Amazon and Constellation finalized a 20-year agreement involving 690 MW and more than $3 billion in investment at Maryland's Calvert Cliffs plant. Together, the two deals commit over $7 billion in new investment and lock in Big Tech as the backbone of Constellation's revenue for decades.

  • Two Mega-Deals in One Week Signal a New Business Model. The Google agreement includes a 20-year power purchase agreement backed by over $4.3 billion for upgrades at 11 nuclear facilities across Illinois, Pennsylvania, and New Jersey, adding 890 MW of new nuclear capacity by 2028.

Separately, the companies signed a 15-year energy supply agreement covering an additional 2,700 MW from Constellation's existing fleet. For shareholders, this means decades of locked-in cash flows from a single creditworthy counterparty — a dramatic shift from selling power into volatile wholesale markets.

  • Constellation Now Has Three Tech Giants Paying for Its Plants. Over the last two years, Constellation unveiled an agreement to restart its Three Mile Island reactor for Microsoft, while Google contracted to restart NextEra's Iowa nuclear plant.

The trend follows similar nuclear energy commitments from Amazon and Microsoft as AI workloads drive unprecedented power demand. Constellation is converting its aging fleet from a cost center into a prized asset — but execution risk across 11 simultaneous plant upgrades is real.

  • The PJM Grid Rule Change Is the Hidden Catalyst. PJM has proposed requiring data center customers to either bring their own power or face being shut off during peak demand — and the Google-Constellation deal is a direct response to that proposal. This regulatory shift effectively forces hyperscalers to sign exactly these contracts, giving Constellation pricing power it never had.

  • The Stock's Surge May Be Getting Ahead of Itself. CEG has jumped from $254 to $303 in under a week — nearly 19% — on two deals that deploy billions over decades. The combined company now controls 55 GW of generating capacity after its $21.8 billion Calpine acquisition earlier this year, meaning the 890 MW of new nuclear represents just 1.6% of total fleet capacity. Investors are paying today for earnings that won't fully materialize until the late 2020s and beyond.