Energy Department Offers Constellation Up to $5 Billion for Nuclear Uprates at Eight Plants

The Department of Energy offered Constellation Energy a conditional loan of up to $5 billion on October 27, 2026, to raise the output of eight existing nuclear plants in Illinois, Maryland and Pennsylvania. DOE says the work will add about 1.1 gigawatts, enough for more than 930,000 homes.

The plants are Braidwood, Byron, Clinton, Dresden, LaSalle and Quad Cities in Illinois, Calvert Cliffs in Maryland and Limerick in Pennsylvania. Their power feeds two grid regions, PJM and MISO. The loan also carries an option to finance later uprates at other Constellation plants. Energy Secretary Chris Wright marked the deal with a visit to Byron the same day.

Photo: MediaGuy768, CC BY-SA 4.0 via Wikimedia Commons

A conditional offer, not a closed loan

The commitment comes from the Office of Energy Dominance Financing, the renamed Loan Programs Office. It isn’t money in hand. Constellation has to meet technical, legal, environmental and financial conditions before DOE signs final loan documents and pays anything out. Several of the office’s recent nuclear deals are at the same stage.

An uprate raises how much power a reactor already running can produce. The usual work is new turbines, generators, pumps and instruments, sometimes with changes to the reactor’s licensed power level that need the Nuclear Regulatory Commission’s approval. It needs no new site and no new reactor, which is why uprates are the fastest way to add nuclear capacity. They’re also limited. Each plant can only be pushed so far.

Some of this work has been in the pipeline for a while. In 2023 Constellation announced an $800 million plan to uprate Byron and Braidwood by about 135 megawatts, and it credited the federal tax credits in the Inflation Reduction Act with making the investment pay. Both plants had been slated for early closure until Illinois passed a state law in 2021 to keep them open. DOE didn’t break the 1.1 gigawatts down by plant, so it isn’t clear how much of the new loan covers projects already planned.

How close Washington is to its 5 gigawatt goal

The loan is tied to a target in one of the President’s May 2025 nuclear orders, “Reinvigorating the Nuclear Industrial Base.” That order told DOE’s lender to prioritize 5 gigawatts of uprates at existing reactors, with a 2030 timeline. In March 2026 DOE launched Project UPRISE, the Utility Power Reactor Incremental Scaling Effort, to get there. DOE’s fact sheet now puts the goal at 2029 and says about 4.7 gigawatts has been identified.

Two loans account for most of that. Constellation’s is the biggest single piece at 1.1 gigawatts. On October 5 DOE offered Vistra a conditional loan of up to $4.2 billion for 433 megawatts of uprates at Beaver Valley in Pennsylvania and Davis-Besse and Perry in Ohio, which also keeps nearly 4 gigawatts running. DOE also counts more than 300 megawatts of uprates in the $26.5 billion loan package for Southern Company’s utilities that closed in February.

“Identified” is a planning word. Two of the three big uprate deals are conditional commitments, and the capacity arrives only as each plant finishes its work during refueling outages.

The wider nuclear book

Uprates are one of three tracks DOE is financing. The second is restarts: Palisades in Michigan with a $1.5 billion loan to Holtec, Crane in Pennsylvania, the former Three Mile Island Unit 1, with $1 billion to Constellation, and Duane Arnold in Iowa with $1.9 billion to NextEra. The third is new construction, led by a $17.5 billion conditional commitment to fund long-lead equipment for new large reactors. The site has tracked how the renamed lender moved its book toward nuclear, gas and the grid and where the AP1000 push and the Palisades restart stand.

Of the three, uprates carry the least construction risk. The reactors exist, the operators know them, and the work happens during outages the plants already schedule. That makes them the most likely piece of the nuclear program to deliver on time. It also means the gigawatts come from plants the country already had.

DOE also claims more than 10,000 project-related jobs from the Constellation work. That figure is the department’s own.

DOE’s demand case is the same one behind its other grid moves. It argues that data centers and new industry are pushing up load faster than new plants can be built. A gigawatt from existing reactors is power that doesn’t wait on a new permit. Whether the loan closes, and on what terms, is the next thing to watch.