Infrastructure · 30 October 2026 · 5 min read

Constellation’s nuclear loan is still conditional. The gigawatts are not funded

On 27 October the Energy Department offered up to $5 billion for uprates at eight plants in Illinois, Maryland and Pennsylvania, and said the work would add nearly 1.1 gigawatts. Constellation says the papers are not signed, and that the offer is not a decision to proceed at every site. The company separately says deals with Google and Amazon prompted plans for more than $7 billion, and about 1,080 megawatts. The department’s figure and the company’s figure are not written as the same number.

Two large concrete cooling towers at a nuclear station, one trailing steam, with fields in the foreground. — The photograph published with coverage of the Byron station in Illinois, one of the eight plants named in the offer. The towers are the plant that already runs. They are not an uprate, and the loan has not closed.

The Energy Department said on 27 October that its Office of Energy Dominance Financing had made a conditional loan commitment of up to $5 billion to Constellation, for nuclear uprates and modernisation at plants in Illinois, Maryland and Pennsylvania. The department says the work will add nearly 1.1 gigawatts, the equivalent of more than 930,000 homes, and support more than 10,000 project-related jobs. The plants it names are Braidwood, Byron, Clinton, Dresden, LaSalle and Quad Cities in Illinois, Calvert Cliffs in Maryland, and Limerick in Pennsylvania. An uprate is more electricity from a reactor that already exists. It is not a new plant, and “will add” is the department’s description of a project that has not been funded.

Both sides say the money is not out. The department says a conditional commitment indicates an intent to lend, and that Constellation must still meet technical, legal, environmental and financial conditions before definitive documents are signed and the loan is funded. Constellation’s own release says the conditional commitment is subject to due diligence, negotiation of definitive financing documents and satisfaction of applicable conditions, and that it does not, by itself, represent a final decision to proceed with any individual uprate or at every facility under consideration. A financial close is a different document. Alliant’s generation loan was described as closed. This one is not.

The customer agreements are older than the loan offer, and they are not the loan. Constellation says recent 20-year agreements with Google and Amazon have incentivised it to invest more than $7 billion to add approximately 1,080 megawatts. An agreement announced last year with Meta, it says, supports a 30-megawatt expansion at Clinton. Constellation said the Google and Amazon agreements show how long-term customer commitments can incentivise billions of dollars of investment. Incentivise is not the same verb as built. Approximately 1,080 megawatts is the company’s figure for what those deals prompted it to plan. Nearly 1.1 gigawatts is the department’s figure for what the uprates would add. The releases do not say the two numbers are the same megawatts, and 1,080 megawatts is not a cheque from the department.

Secretary Chris Wright called uprates a way to get more from plants that already exist. That can be true of a turbine change and still not be true this year. Nothing in either release gives a date the first extra megawatt would reach the grid, a price for the electricity, or a statement that any of the eight plants has already been uprated under this offer. Until the documents are signed and a reactor is producing the extra power, the news is a conditional offer and a set of customer contracts. It is not 1.1 gigawatts on the system.