Dec. 18, 2025 — Constellation Energy Corporation (NASDAQ: CEG) is back in the spotlight after a sharp pullback that hit many “AI power” and nuclear-linked names at once. CEG was recently trading around $340.97, down about 6.8% versus the prior close. [1]
The move comes even as the fundamental newsflow around Constellation has been broadly constructive: a record-setting PJM capacity auction that underscored tightening power supply, fresh federal license renewals for major Illinois nuclear plants, and another step forward in Constellation’s Calpine acquisition process—highlighted today by a Federal Register notice detailing the Justice Department’s proposed settlement and divestiture requirements. [2]
Below is what’s driving Constellation Energy stock on 18.12.2025, what the latest headlines mean for the business, and what analysts are watching next.
Why Constellation Energy stock fell: the “AI power trade” wobbles again
CEG’s drop is less about a single Constellation-specific negative headline and more about a broad de-risking in power and AI-adjacent infrastructure stocks—triggered by renewed debate over how much electricity future AI systems will really need.
A key narrative catalyst: a funding round for AI chip startup Mythic, which reignited market anxiety that more power-efficient chips could reduce the long-term electricity demand implied by today’s data-center boom. That “maybe the AI buildout won’t be as power-hungry as priced” fear hit several power-related winners at once; Barron’s noted Constellation and peers falling sharply in the same session. [3]
That matters because, in 2024–2025, Constellation increasingly traded like a “picks-and-shovels” play on AI infrastructure: not a software company, but a large-scale supplier of the one thing every data center ultimately consumes—reliable electricity.
The PJM capacity auction: record prices, a reliability shortfall, and a giant demand signal from data centers
If you want the most important power-market datapoint in today’s CEG story, it’s this: PJM’s 2027/2028 Base Residual Auction cleared at the FERC-approved cap of $333.44/MW-day across the PJM footprint. PJM said the auction procured 134,479 MW of unforced capacity (UCAP) and demand response, with additional fixed resource requirement (FRR) regions procuring more—bringing the total available to 145,777 MW UCAP. [4]
The bullish interpretation for generators like Constellation
High capacity prices generally mean higher future capacity revenues for generators that clear the auction—one reason investors have been enthusiastic about established nuclear and gas fleets in constrained regions.
TipRanks reported that Constellation said all of its PJM power plants cleared the 2027–2028 auction, with results effective June 1, 2027, supporting continued monetization through capacity revenues. [5]
The bearish (or at least politically complicated) interpretation
PJM also said the region fell short of its reliability requirement by 6,623 MW, the first time the entire RTO (including FRR areas) fell short—though PJM cited mitigating factors and stated it still expects to be “very close” to its reliability standard in the delivery year. [6]
Reuters framed the same auction as a warning sign for consumers: record-high capacity prices could continue pushing power bills higher across a region serving about one-fifth of Americans, after some areas saw bills jump more than 20% starting last summer. [7]
The detail that ties PJM directly to AI growth
PJM’s release included a blunt demand signal: the forecast peak load for 2027/2028 is ~5,250 MW higher than the prior year’s forecast, and nearly 5,100 MW of that increase is attributable to data center demand. [8]
So even on a day when markets questioned AI’s ultimate power appetite, PJM’s planning numbers—at least in this footprint—point in the opposite direction: data centers are already reshaping load forecasts at grid-operator scale.
NRC renews licenses for Clinton and Dresden: extending cash-flow runway into mid-century
One of the most Constellation-specific positives this week is regulatory: Constellation said the U.S. Nuclear Regulatory Commission approved 20-year license renewals for its Clinton and Dresden clean energy centers in Illinois. [9]
Key details from Constellation’s announcement:
- Clinton is approved to operate through 2047
- Dresden’s reactors are approved to operate through 2049 and 2051
- Constellation said it is investing more than $370 million in upgrades tied to relicensing efforts
- The company said the renewals preserve 2,200+ jobs and $8.1 billion in tax revenues (federal, state, and local) [10]
Reuters also highlighted the same approvals and investment figure, placing them in the broader context of rising nuclear demand linked to data centers and electrification. [11]
For CEG stock, license extensions are not just feel-good policy wins—they can reduce “end-of-life” uncertainty on major assets, which can support valuation when markets are pricing long-duration cash flows.
Calpine acquisition: what changed today (and why it matters)
Constellation’s planned acquisition of Calpine has been one of the biggest strategic swings in U.S. power markets. The deal was announced in January 2025 as a move to combine major nuclear scale with a large natural-gas generation and retail platform. [12]
Today’s headline: the Federal Register notice (Dec. 18, 2025)
A Department of Justice Antitrust Division notice published today in the Federal Register lays out the government’s proposed settlement structure under the Antitrust Procedures and Penalties Act (the “Tunney Act”), including the specific facilities that must be divested. [13]
According to the notice, the DOJ alleged the acquisition would violate Section 7 of the Clayton Act, and the proposed final judgment requires divestitures in:
ERCOT (Texas)
- Jack A. Fusco Energy Center (near Houston)
- Calpine’s minority ownership interest in Gregory Energy Center (near Corpus Christi)
PJM
- Bethlehem Energy Center (PA)
- Edge Moor Energy Center (DE)
- Hay Road Energy Center (DE)
- York Energy Center (York 1 and York 2) (PA) [14]
The notice also states that public comment is invited within 60 days. [15]
The earlier official steps that set up today’s publication
On Dec. 5, the DOJ announced it would require divestitures to address competition concerns, describing the transaction as a proposed $26.6 billion acquisition and stating the remedy involves divesting six power plants across Delaware, Pennsylvania, and Texas. [16]
Also on Dec. 5, Reuters reported Constellation reached an agreement with DOJ on conditions to complete what Reuters described as a $16.4 billion acquisition (different headline number than DOJ’s; deals are often reported with different valuation conventions). [17]
Constellation’s own statement: “final regulatory clearance”
Constellation said the DOJ resolution marked the final regulatory clearance needed to complete the transaction, and added detail on required divestitures. It stated that:
- FERC approved the transaction conditioned on divestiture of four Calpine Mid-Atlantic assets (Hay Road, Edge Moor, Bethlehem, York 1)
- The DOJ resolution adds divestitures including York 2 (828 MW, PA), Jack Fusco (605 MW, TX), and a minority interest in Gregory (385 MW, TX)
- Closing can begin once the court signs the stipulation and order agreed to by the parties and DOJ [18]
A financing breadcrumb: Constellation’s 8‑K on Calpine note exchanges
In a Dec. 9 Form 8‑K, Constellation disclosed it was commencing private exchange offers and related consent solicitations tied to multiple series of outstanding Calpine notes—an example of the capital-structure work that often runs alongside large mergers. [19]
Earnings and operating backdrop: what Constellation last reported
While today’s tape action is dominated by macro narratives, Constellation’s most recent quarterly release still anchors many models.
In its third-quarter 2025 update, Constellation reported:
- GAAP net income of $2.97 per share
- Adjusted (non-GAAP) operating earnings of $3.04 per share
- Full-year 2025 adjusted operating earnings guidance narrowed to $9.05–$9.45 per share
- Nuclear output (including owned output from Salem and South Texas Project) of 46,477 GWh in Q3 2025; excluding Salem and STP, Constellation cited a 96.8% capacity factor for its nuclear plants at ownership [20]
Those operational metrics matter because nuclear economics can swing with outage performance, refueling schedules, and realized power prices—especially when a stock is priced for both growth and reliability.
Analyst forecasts and price targets for CEG stock: bullish, but with valuation scrutiny
Despite the selloff, “Street math” still skews positive.
MarketBeat’s compilation shows Constellation with:
- A consensus price target around $405.93
- A high forecast around $481 and a low around $258
- A “Moderate Buy” consensus based on analyst ratings (as compiled by the site) [21]
On the incremental news side, MarketScreener reported that UBS raised its price target to $420 from $385 while maintaining a Buy rating (via MT Newswires). [22]
At the same time, valuation is clearly part of the conversation. MarketBeat listed CEG at a P/E ratio around 39 and a dividend yield around 0.45%, a combination that signals the market is pricing CEG less like a sleepy utility and more like a long-duration infrastructure growth asset. [23]
What investors are watching next: 5 near-term catalysts that could move CEG stock
- PJM follow-through after the auction
PJM said it will conduct an Incremental Auction for the 2027/2028 delivery year in February 2027, and that its board is considering proposals related to integrating data centers and other large loads. Policy reaction risk is real when bills rise—but so is the incentive to build capacity. [24] - Calpine closing timeline and divestiture execution
The path now runs through court process and divestiture logistics. Today’s Federal Register notice (and comment period) is part of that machinery. [25] - Nuclear fleet performance and additional life extensions
The Illinois renewals extend major assets deep into the 2040s/2050s—great for duration, but the market will keep scoring execution: outage discipline, capex, and regulatory relationships. [26] - Big Tech demand signals: buildout continues, but efficiency narratives can whipsaw the trade
Today’s selloff shows how sensitive “power-for-AI” stocks are to any hint that compute efficiency improves faster than load growth. Barron’s linked the day’s volatility directly to that debate. [27] - 2026 guidance and the shape of realized power pricing
Constellation’s 2025 guidance range is set; the next big re-rating moments typically come from updated forward expectations and proof that market structure (capacity + energy) can support earnings durability. [28]
Bottom line on Dec. 18, 2025: CEG is caught between two powerful narratives
Constellation Energy stock is living in the overlap of three structural stories:
- Grid tightening and capacity price escalation (especially in PJM)
- Nuclear asset longevity reinforced by license renewals
- Scale transformation via the Calpine acquisition—plus the regulatory conditions attached to it [29]
Today’s pullback looks like a reminder that even strong fundamentals can be temporarily overruled by market positioning and narrative shocks—particularly when a stock is treated as a proxy for the AI infrastructure cycle.
References
1. www.marketbeat.com, 2. www.pjm.com, 3. www.barrons.com, 4. www.pjm.com, 5. www.tipranks.com, 6. www.pjm.com, 7. www.reuters.com, 8. www.pjm.com, 9. www.constellationenergy.com, 10. www.constellationenergy.com, 11. www.reuters.com, 12. www.constellationenergy.com, 13. www.federalregister.gov, 14. www.federalregister.gov, 15. www.federalregister.gov, 16. www.justice.gov, 17. www.reuters.com, 18. www.constellationenergy.com, 19. www.sec.gov, 20. www.constellationenergy.com, 21. www.marketbeat.com, 22. www.marketscreener.com, 23. www.marketbeat.com, 24. www.pjm.com, 25. www.federalregister.gov, 26. www.constellationenergy.com, 27. www.barrons.com, 28. www.constellationenergy.com, 29. www.pjm.com
