NEW YORK, December 29, 2025, 23:50 ET — Market closed
- Constellation Energy shares closed down 0.6% at $358.33.
- Utilities were modestly higher, while U.S. stocks ended lower in holiday-thinned trading.
- Investors continue to track power-demand drivers and the company’s pending Calpine acquisition steps.
Constellation Energy Corp shares slipped 0.6% on Monday, ending at $358.33 as trading volumes thinned in the final week of the year.
The dip matters because Constellation has become a proxy for the U.S. power-demand boom tied to artificial intelligence data centers, which are pushing grid planners and regulators to focus on supply constraints and reliability.
That backdrop has kept power producers in the spotlight even on quiet sessions, with investors balancing long-term demand themes against near-term catalysts such as regulatory milestones and financing steps tied to big deals.
Constellation traded between $356.63 and $369.00 and finished below its $360.00 opening price.
Utilities broadly held up, with the Utilities Select Sector SPDR Fund edging up about 0.2%. Vistra and NRG were little changed, while Talen fell about 1%.
Wall Street’s main indexes ended lower as technology shares retreated from last week’s gains that pushed the S&P 500 to record highs, according to Reuters. Minutes from the Federal Reserve’s previous meeting and weekly jobless claims are due later this week in an otherwise light data calendar. 1
For Constellation, traders have stayed focused on the power-price outlook in key markets such as PJM Interconnection, which runs the grid across a 13-state Mid-Atlantic and Midwest region. Capacity prices — payments to generators for being available when the grid needs them — hit $333.44 per megawatt-day in PJM’s latest auction, Reuters reported earlier this month. 2
Another overhang is Constellation’s planned acquisition of Calpine, a deal that would expand its generation footprint beyond its nuclear-heavy base. Constellation said on Dec. 5 it reached a resolution with the U.S. Department of Justice and that the Federal Energy Regulatory Commission approved the deal subject to divestitures, Reuters reported. 3
Financing steps tied to the Calpine transaction remain in motion. Constellation Energy Generation said on Dec. 23 it extended the expiration of private exchange offers and related consent solicitations for certain Calpine notes, moving the deadline to Jan. 12, 2026. 4
Constellation has also moved to extend the operating lives of key nuclear assets. The U.S. nuclear regulator approved 20-year license renewals for the Clinton and Dresden plants, Reuters reported, and Constellation chief generation officer Bryan Hanson said, “These license extensions will allow Clinton and Dresden to stay online for another two decades.” 5
Before the next session, traders are likely to watch for any regulatory filings or divestiture updates tied to the Calpine deal, along with power-market signals that affect forward pricing and contract demand across PJM and other regions.
Market calendars estimate Constellation’s next earnings date in mid-February, though the company has not confirmed a publication date. 6
On the technical side, Monday’s low near $356.63 is the closest support level on traders’ screens, while the session high near $369.00 marks the first resistance point after the stock’s late-December range.
