Constellation Energy -- How the Business Works
Natural Gas (Calpine): ~33 GW of primarily combined-cycle and peaking gas plants. Dispatches during high-demand periods to complement nuclear baseload. Provides flexibility for customer solutions.
Geothermal: The Geysers complex in California -- the largest geothermal facility in the world. Provides renewable baseload generation with high capacity factors.
Retail Supply: 2.5 million residential and commercial customers served directly. Provides stable, recurring revenue base.
Data Center Contracts: Structuring deals both in front of and behind the meter. Pairing nuclear with gas, batteries, and demand response. Buyers described as "far more sophisticated and aggressive" with each passing quarter.
Capacity Markets: PJM capacity auctions provide additional revenue for maintaining reliable generation. The 2025/2026 auction delivered meaningfully higher capacity revenues. CEG is the dominant generator in PJM.
Clean Energy Policy: Bipartisan support for nuclear energy. Executive orders and PJM rulemaking expected to clarify data center interconnection rules.
Nuclear power plants have a unique economic profile. Once the reactor is fueled and operating, the marginal cost of producing each additional MWh is near zero -- uranium fuel represents less than 10% of total operating cost. This means that virtually all revenue above fixed operating costs flows directly to the bottom line.
The fleet runs at 94%+ capacity factors, meaning the plants produce power more than 94% of all hours in a year. This is ~4 percentage points above the U.S. nuclear industry average and far above wind (~35%) or solar (~25%) capacity factors. Nuclear delivers firm, 24/7 baseload power regardless of weather conditions -- exactly what data centers require.
Asset lives extend 40+ years, with most operating licenses being extended to 60 or even 80 years by the NRC. These are effectively perpetual infrastructure assets with no replacement pathway -- building new nuclear capacity takes 10-15 years and costs $10B+ per GW. The existing fleet is irreplaceable at any reasonable cost or timeline.
The IRA nuclear production tax credits (~$25/MWh, inflation-adjusted) guarantee a minimum revenue per MWh, creating a price floor that backstops base earnings in any power price environment. When wholesale prices exceed the PTC threshold, nuclear units capture full market upside with no cap. This asymmetric payoff -- floored downside, uncapped upside -- is the core of the investment thesis.
The Calpine acquisition, closed January 2026, transforms Constellation from a nuclear-focused generator into the largest and most diversified power producer in the United States. The strategic logic is straightforward: nuclear provides clean, low-cost baseload power, but customers -- especially data centers -- also need flexible peak capacity. By pairing nuclear with gas, Constellation can offer a complete power solution that no competitor can match.
The Geysers -- Calpine brings the largest geothermal complex in the world, located in Northern California. Geothermal provides renewable baseload generation with high capacity factors, complementing the nuclear fleet and adding clean energy credentials in a state where nuclear is not available.
Financial impact: Management expects $2B+ annual incremental free cash flow and ~$2 of EPS accretion in FY2026, despite DOJ-mandated divestitures (York 2 and Jack Fusco stations) and higher-than-expected purchase accounting depreciation. The underlying Calpine business is "performing better than originally projected." A $5B share repurchase authorization provides additional capital allocation flexibility, and no buyback is included in the guided 20%+ base EPS CAGR through 2029.
Nuclear Generation (core franchise). Constellation operates ~22 GW of nuclear capacity across 13 sites, representing ~23% of all U.S. nuclear output. The fleet produced 182,690 GWh in FY2025 at a 94.7% capacity factor. Nuclear plants run continuously as baseload generators -- they produce the same amount of power whether demand is high or low, day or night, summer or winter. Fuel costs are minimal (uranium is cheap relative to energy output), so the marginal cost of each additional MWh is near zero. Revenue comes from selling this power into wholesale markets, through long-term PPAs, and directly to retail customers. The IRA nuclear production tax credits (~$25/MWh) guarantee a minimum revenue floor, while market prices above that level flow directly to earnings. The Crane Clean Energy Center (formerly TMI Unit 1) restart -- an ~835 MW reactor with a 20-year Microsoft PPA -- would be the first-ever restart of a decommissioned U.S. nuclear plant if successful in 2027.
Natural Gas Generation (Calpine fleet). The ~33 GW Calpine gas fleet consists primarily of combined-cycle gas turbines (CCGTs) and simple-cycle peaking plants. CCGTs are efficient, lower-emission gas plants that can run for extended periods. Peakers fire up during high-demand hours -- hot summer afternoons, cold winter mornings -- earning premium prices during scarcity. The gas fleet complements nuclear: where nuclear provides steady, 24/7 baseload, gas provides the flexibility to ramp up and down with demand. For data center customers, this means Constellation can guarantee both continuous clean power (nuclear) and backup/peak capacity (gas) under a single contract. The gas fleet also participates in PJM and other capacity markets, earning payments for being available to generate when the grid needs it most.
Geothermal (The Geysers). The Geysers in Northern California is the largest geothermal complex in the world, producing electricity from naturally occurring underground steam. Geothermal is a renewable baseload resource -- like nuclear, it generates power continuously without depending on weather. The Geysers provide Constellation with a clean energy asset in California, where the company has no nuclear presence. This broadens the geographic and customer reach of the clean energy platform.
Commercial Platform (PPAs, retail, data centers). The commercial business serves as the distribution layer for all generation assets. Constellation sells power through three primary channels. First, long-term PPAs with corporates, utilities, and data centers provide contracted, predictable revenue -- the pipeline stands at 147 million MWh of contracted and targeted deals. Second, wholesale market participation in PJM and other ISOs captures real-time pricing. Third, retail supply to 2.5 million residential and business customers provides stable, recurring cash flow. The commercial team structures increasingly sophisticated deals for data center customers, offering configurations that include both front-of-meter and behind-the-meter power supply, paired with batteries and demand response.
Regulatory and Policy Framework. The regulatory pillar underpins the economics of the entire business. Nuclear PTCs under the IRA provide the earnings floor (~$25/MWh). PJM capacity market payments compensate generators for maintaining reliable capacity. State-level clean energy standards create demand for zero-carbon power. Federal policy under both administrations has been supportive of nuclear, and Constellation actively engages with policymakers on data center interconnection rules, capacity market reform, and clean energy incentives. CEO Dominguez has positioned the company to adapt commercial structures to any regulatory outcome -- whether colocation, behind-the-meter, or traditional grid-connected configurations.