Amazon signs 20-year Calvert Cliffs PPA backing a 190 MW nuclear uprate

Constellation and Amazon announced on September 30, 2026 a 20-year power purchase agreement at the Calvert Cliffs Clean Energy Center in Lusby, Maryland. Per Constellation's release, the agreement "includes 690 megawatts of power, including the 190 megawatt uprate," and will enable more than $3 billion of Maryland infrastructure investment, including improvements across the entire 1,790 MW plant and approximately 190 MW in total of new generating capacity coming online between 2030 and 2032. The parties also entered a related retail supply agreement to support Amazon operations in the 13-state PJM market, the release says. Neither the release nor Amazon's Calvert Cliffs update names a price.

Constellation frames the contract as doing two more things. In the release's words, Amazon's commitment "will help provide Constellation with the revenue certainty to relicense the plant for another 20 years" and, as the release puts it, make progress toward "new clean energy power plants at the site." The electricity, the release says, "will continue flowing to the PJM regional grid just as it does now." Joe Dominguez, Constellation's chairman, president and chief executive officer, is quoted: "This agreement demonstrates how private investment can strengthen critical energy infrastructure." Maryland Matters, whose September 30, 2026 report includes an interview with Constellation senior executive vice president David Dardis, said the financial specifics of the deal remain confidential and quoted him on forecasting: "And one thing we know about future power prices is: We're always wrong."

Amazon's version of the deal, on its carbon-free energy updates page, carries figures the Constellation release does not. Amazon puts the 190 MW at "enough to power about 147,000 U.S. homes" and says the companies "are exploring ways to generate even more carbon-free energy at the site, including new nuclear units." Constellation's release narration says "new clean energy power plants" and the Dominguez quote "advanced nuclear technologies"; per Maryland Matters' September 30 report, Constellation also said it plans to evaluate the possibility of new small modular nuclear reactors on the site.

Licenses, uprates and the regulator

Calvert Cliffs is two pressurized water reactors whose licenses have been renewed once already: the NRC's facility pages list Unit 1's license as issued July 31, 1974, renewed March 23, 2000 and expiring July 31, 2034, and Unit 2's as issued August 13, 1976, also renewed March 23, 2000, and expiring August 13, 2036.

A further 20 years would come through subsequent license renewal. The NRC's status page for those applications, last reviewed September 15, 2026, shows no Calvert Cliffs application received, under review or completed: its received section reads "No content at this time," its under-review section names three other plants, and Calvert Cliffs is not among the completed applications. The future-submittals table names no Calvert Cliffs entry either, but it carries four Constellation Energy Generation submittals whose plant the NRC lists as "Unnamed," letter of intent "Proprietary," notice of intent dated December 7, 2023, two scheduled for 2030 and two for 2034; the page does not rule out a planned Calvert Cliffs filing. The release names no date for an application and does not mention the NRC.

The uprate is a licensing action as well: the NRC's power uprates page says the maximum power level "is included in the license and technical specifications for the plant" and that a licensee may change those documents only after the NRC approves its application. The release's schedule puts the new capacity online between 2030 and 2032, inside the current licenses.

Constellation's hyperscaler contracts, compared

Two earlier Constellation agreements with the same term and the same kind of buyer each attached a different nuclear project. The September 20, 2024 agreement with Microsoft was for a restart: Constellation said the 20-year PPA would "pave the way for" the launch of the Crane Clean Energy Center and the restart of Three Mile Island Unit 1, a plant the release subhead put at "approximately 835 megawatts"; the Department of Energy later closed a $1 billion loan for that restart. The June 3, 2025 agreement with Meta covered the output of the Clinton Clean Energy Center, 1,121 MW, beginning in June 2027, when Constellation said Illinois's ratepayer-funded zero emission credit program expires; that release said the deal would expand Clinton's output by 30 MW through plant uprates. At Calvert Cliffs the uprate is the headline: 190 MW, against Clinton's 30 MW, at a plant that is operating today.

Amazon's side of the pattern is the grid connection. Its June 11, 2025 agreement with Talen Energy for Susquehanna in Pennsylvania, 1,920 MW at the full contract quantity through 2042 in Talen's words, came with a plan to move the existing co-located arrangement to what Talen called a "front-of-the-meter" arrangement after transmission reconfigurations Talen expected in the spring of 2026. Calvert Cliffs starts where Susquehanna was headed: the release says all the plant's output "will continue flowing to the PJM regional grid just as it does now," and Dardis told Maryland Matters, "Nothing about this agreement changes that."

The grid in question is short. As The Duck Curve reported on October 1, 2026, FERC accepted PJM's one-time Reliability Backstop Procurement on September 29, 2026 but suspended it to February 28, 2027; the procurement would buy up to 6,831 MW, per the order the amount by which PJM's 2028/2029 Base Residual Auction cleared short of the reliability requirement once Fixed Resource Requirement resources are counted, before offsets and opt-outs. The Calvert Cliffs uprate's 2030-to-2032 window lands after that delivery year.

The county where Amazon withdrew a data center

Amazon's previous Calvert County proposal ended differently. On August 4, 2026, Maryland Matters reported, citing a county news release, that Amazon Web Services was abandoning its plans to develop data centers on the Calvert Cliffs campus; per a county planning document the outlet cited, the proposal was for "multiple data center campuses" covering 2.4 million square feet, and the company had submitted it to the county in early May. The same report said the three county commissioners who had voted against a pause on data centers were all ousted in their primaries.

On September 30, 2026, Dardis told Maryland Matters that Constellation remains open to a data center or another large customer at the site but that as of now "nothing is in the works," and that "we would only do so in partnership with Calvert County and other important stakeholders."

He also said Constellation will likely seek other long-term contracts with power users in Maryland; that could include the state's utilities, which he said could use power purchase agreements to hedge their power costs.

Outlook

If Constellation means to relicense on the strength of this contract, the first public sign would be a letter of intent or a named entry in the NRC's future-submittals table, where four Constellation rows now sit as "Unnamed"; the release gives no filing date, and the 2030-to-2032 window for the uprate implies an uprate application well before then. Dardis's remark that Maryland's utilities could be among the next contract partners suggests more of the post-uprate plant, roughly 1,290 MW by our arithmetic (1,790 MW plus 190 MW, less the 690 MW contracted), could be sold on long-term terms; no such contract has been announced.