Google, Constellation plan 890 MW in nuclear uprates

Google and Constellation Energy have signed a 20-year agreement intended to add 890 megawatts (MW) to the PJM Interconnection grid by upgrading 11 operating nuclear units. The deal gives a major electricity buyer a direct role in financing more output from existing plants, with the first uprate expected by 2028; it does not fund a new reactor.

Key facts

• The agreement targets 890 MW of added capacity from upgrades at 11 units.
• The 20-year power purchase agreement supports equipment and technology investments at plants in Illinois, Pennsylvania and New Jersey.
• Constellation expects the first uprate to be delivered by 2028.
• A separate 15-year agreement covers an additional 2,700 MW in PJM's existing fleet.
• Constellation says it will invest more than $4.3 billion in connection with the collaboration.

What happened

Google and Constellation said the 20-year power purchase agreement will support new equipment and technology at 11 Constellation-owned nuclear units in Illinois, Pennsylvania and New Jersey. Improvements to thermal and electrical efficiency are meant to increase generation available to the PJM system, rather than shift output from one buyer to another.

The companies also announced a distinct 15-year energy supply agreement for 2,700 MW from Constellation's existing PJM fleet. That arrangement is intended to give operating assets longer-term revenue certainty. The 2,700 MW figure is not part of the 890 MW of additional capacity: one describes an energy supply commitment from existing generation, the other a planned gain in capacity from uprates.

Constellation says the collaboration represents more than $4.3 billion in investment and will sustain about 4,400 existing jobs while creating roughly 7,200 construction jobs during the work. These are company estimates associated with the program, not independently audited employment outcomes. The first incremental capacity is expected in 2028, but the release does not provide a unit-by-unit schedule or specify how much each of the 11 reactors is expected to gain.

The announcement also includes a five-year technology alliance. Constellation plans to use Google Cloud and Gemini Enterprise in work related to generation operations, infrastructure planning and grid security. That agreement is separate from the power purchase and uprate commitments; it does not change the stated 890 MW target.

Why it matters

The deal puts a long-term electricity contract behind a defined package of upgrades to the existing nuclear fleet. Data centers and other large electricity users are seeking firm supply as their demand grows. By connecting a buyer's contract to plant modernization, Google and Constellation are testing a route to new grid capacity that does not depend on completing a greenfield reactor project.

The distinction matters for both timing and claims. An uprate can involve equipment replacements, plant modifications and regulatory review, but it does not require building a new reactor island. The companies have set 2028 as the target for the first delivery, while the full 890 MW is a program target rather than a single near-term commissioning event.

The deal's second 2,700 MW commitment shows another financial mechanism at work: a buyer can underpin revenue from existing generation without that amount necessarily representing additional capacity. Keeping the categories separate avoids overstating the size of the nuclear expansion. The same discipline applies to employment and investment figures, which remain company projections at announcement.

Background

This agreement follows a series of corporate arrangements tied to existing nuclear plants. Constellation and Amazon announced a separate Calvert Cliffs power purchase agreement tied to plant investment. Google's agreement with Constellation is broader in its number of sites and target capacity, but the commercial logic is related: long-term buyer commitments can support plant investment and continued operation.

NNN's guide to nuclear power and data centers tracks how major technology companies are contracting for reliable electricity. Earlier Google arrangements have also linked power purchases to existing plants, including the company's agreement with Fortum for Finland's Loviisa plant. Those contracts differ in their structure and geography, so the 890 MW figure should be read as a specific PJM uprate program, not as a proxy for all nuclear supply Google has contracted.

PJM operates the high-voltage grid across parts of the Mid-Atlantic and Midwest. A capacity increase at a generating plant does not by itself resolve transmission constraints or guarantee delivery to a particular data center. The new megawatts enter a regional system; grid operators, transmission owners and regulators still determine how supply and demand are balanced.

What's next

The next concrete test is delivery of the first uprate by 2028. The public announcement does not name the first unit, give interim construction dates or break down the anticipated gains by site. Those details will show how the 890 MW target moves from a commercial commitment into plant work and grid capacity.

Watch for Constellation's project schedule and any required Nuclear Regulatory Commission approvals or filings tied to individual modifications. The companies also need to clarify how the 15-year, 2,700 MW supply agreement interacts with existing contracts and PJM market obligations. For now, the announced structure combines a long-term purchase commitment with upgrades at operating reactors; the scale and pace of delivery remain to be demonstrated.