Amazon's 20-year contract pays for a 190 MW nuclear uprate at Calvert Cliffs due in 2030-32

The 690 MW in the contract includes the uprate ^[2]. Take out the 190 MW and about 500 MW is output the plant already produces ^[2]. That is roughly 28% of its 1.79 GW ^[3]. The uprate adds about 10.6% to current capacity ^[1]. Constellation's preliminary analysis in February 2025 put the possible gain at roughly 10%, so the figure has held ^[8].

That February 2025 announcement came five to seven years before the 2030-32 window for first new power ^[5]. Constellation is also spending $68 million on 24 electrical breakers to upgrade the plant substation ^[9]. In November 2025 it sized the uprate and said "new equipment and technology" would be required ^[10]. Its public description of the work Amazon is funding stops at "state-of-the-art improvements" across the plant ^[6].

The regulator has no schedule yet. Scott Burnell, a senior public affairs officer at the NRC, told ENR that plant owners file uprate and license-renewal requests publicly. He said the commission can provide a review schedule only after it finds an application acceptable ^[13]. The agency also held an earlier closed session with Constellation, on Feb. 25, about potential power-uprate requests at plants it did not identify ^[14].

The license dates are the constraint that is easy to miss. The same contract pays for the extra megawatts and for the license years they need. If the uprate arrives at the end of its window, Unit 1 has about two years of operation left under its current license ^[4]. A 20-year contract signed this decade outlasts both units' current licenses ^[6]. ENR reports that the deal gives Constellation the revenue certainty to seek another two decades of operation ^[4]. The more than $3 billion is split across the uprate, plant modernization and work supporting longer operation ^[6].

Calvert Cliffs has done this twice before. In 1977 it became the first US plant approved for a power uprate: a 5.5% stretch uprate of 140 MWt on each of its two Combustion Engineering pressurized-water reactors ^[15]. In 2009 the NRC approved a 1.4% measurement-uncertainty-recapture uprate of 37 MWt per unit ^[16]. Those figures are thermal megawatts. The 190 MW is quoted as an increase in output ^[1], so the earlier percentages and the new 10.6% are measured on different bases.

ENR's report covers one plant and does not address regional supply or demand. It cannot support a general claim that power will be scarce. For this contract, I'd plan on 2032, the late end of Constellation's window. I'd also treat the 190 MW as conditional on an uprate review and a license renewal that have yet to happen ^[3][13][5].