Constellation Energy and Amazon on Sept. 30, 2026, announced a 20-year power purchase agreement covering 690 MW from the Calvert Cliffs Clean Energy Center in Lusby, Md., according to Constellation's announcement. The contracted amount includes a 190-MW uprate at the plant; Constellation said about 190 MW of new capacity is expected to come online between 2030 and 2032. A related retail supply agreement supports Amazon operations in the 13-state PJM market.
Constellation tied the contract to the plant's long-term future. The company said Amazon's commitment gives it the revenue certainty to relicense Calvert Cliffs for another 20 years, and that the agreement is expected to enable more than $3 billion in Maryland infrastructure investment, including upgrades across the entire plant. Constellation also said the commitment supports progress toward developing new clean energy power plants at the site, including advanced nuclear technologies.
The Plant and the Contract
Calvert Cliffs sits on the western shore of the Chesapeake Bay in Calvert County and is Maryland's only nuclear plant. Constellation puts its total capacity at 1,790 MW and says it is the state's largest clean energy source, producing about 80% of Maryland's clean energy and enough electricity to power more than 1.3 million homes. The company says the plant employs more than 800 people and pays about $21 million a year in taxes that support schools, roads and other public services.
The deal has two parts: the long-term PPA for 690 MW, which includes the planned uprate, and the separate retail supply agreement tied to Amazon's operations in PJM. Constellation said all electricity from Calvert Cliffs continues to flow to the PJM regional grid.
Amazon's own account, posted on its energy updates page under a Sept. 30 entry, says the upgrade adds 190 MW of carbon-free power, roughly 147,000 U.S. homes' worth, and that its commitment protects "about 850 skilled, well-paying jobs." Amazon also said the commitment "lays the groundwork to explore next-generation nuclear technology at the site." On the same page, the company said its investment in Maryland since 2010 exceeds $20 billion and that it supports more than 33,000 direct and indirect jobs in the state.
What the Companies Said
Constellation Chairman, President and CEO Joe Dominguez said in the company's announcement: "This agreement demonstrates how private investment can strengthen critical energy infrastructure."
Kerry Person, Amazon Web Services vice president of global operations and data center delivery, said in the announcement that "Amazon is committed to investing in carbon-free energy to strengthen the grid and benefit the communities where we operate." Person also said the agreement "supports hundreds of jobs, and brings significant new generation to the regional grid," as quoted from the release by Utility Dive.
Constellation described the deal in the release as an example of "how large energy users can support investments in new, reliable generation while strengthening the broader electric system," according to Utility Dive.
Context: Constellation's Corporate Nuclear Contracts
The Calvert Cliffs agreement follows other long-term corporate contracts for Constellation's nuclear fleet. Utility Dive reported that Walmart entered a long-term PPA with Constellation earlier in 2026 for nuclear energy, environmental attributes and capacity supporting its Illinois operations, and that Constellation signed a nuclear PPA with Meta in 2025 tied to an Illinois nuclear facility. That agreement "will give Meta 1,121 megawatts of nuclear energy beginning in June 2027," Utility Dive reported. Constellation, headquartered in Baltimore, says its fleet totals 55 GW across nuclear, natural gas, oil, geothermal, hydro, wind and solar, and provides about 10% of the nation's clean energy.
What Happens Next
The uprate is the next on-the-record milestone: Constellation and Amazon both give 2030 to 2032 as the expected window for the roughly 190 MW of new capacity to come online. Constellation has said the agreement allows it to relicense Calvert Cliffs for another 20 years but has not announced a date for a relicensing application.
