Amazon Invests in Nuclear Power: 20-Year Deal with Constellation Energy for 190 MW Capacity

Amazon and Constellation Energy announced a 20-year power purchase agreement (PPA) on September 30, 2026 for 690 megawatts at the Calvert Cliffs Clean Energy Center in Maryland. This includes approximately 190 megawatts of additional capacity to be created through a performance upgrade of the existing facility. The agreement requires capital investments exceeding $3 billion and is part of Amazon's strategy to meet the growing electricity demand of its data centers with carbon-free energy.

Expansion of existing facility instead of new construction

The 190 megawatts of additional capacity will result from expanding the already existing Calvert Cliffs nuclear facility. Construction of new reactors is not required for the project. Constellation Energy, the largest operator of nuclear power plants in the United States, has operated the Maryland facility for decades. The deal provides the company with long-term planning certainty and capital for modernization.

Joe Dominguez, CEO of Constellation Energy, stated on September 30, 2026 that the agreement demonstrates "how private investments can strengthen critical energy infrastructure". Amazon's commitment creates a solid foundation for future investments both in the facility itself and in advanced nuclear technologies.

Strategy for carbon-free electricity

Amazon is driving the expansion of carbon-free electricity sources to power its data centers. The electricity consumption from cloud services and AI applications is rising continuously. With the nuclear power deal, Amazon secures a stable, weather-independent energy source with zero operational CO₂ emissions.

It is not Amazon's largest nuclear power contract: the company agreed in June 2025 with Talen Energy to purchase up to 1,920 megawatts from the Susquehanna nuclear power plant in Pennsylvania. Unlike solar or wind projects, nuclear power plants provide baseload power around the clock. The 190 megawatts correspond mathematically—measured by the average annual electricity consumption of a U.S. household—to the needs of approximately 150,000 households, but at Amazon they are used to operate data centers.

Market reaction to the announcement

Constellation Energy shares (NASDAQ: CEG) rose up to 5 percent in after-hours trading on September 30, 2026. In late night trading, the stock was up 2.7 percent. Investors viewed the long-term revenue security from the 20-year contract positively.

Amazon shares (NASDAQ: AMZN) showed no unusual movements following the announcement. For the company, the investment of over $3 billion is part of a broader strategy to secure its energy supply.

Significance for the U.S. nuclear sector

The deal is a signal for the renaissance of nuclear power in the United States. While Europe discusses phasing out nuclear energy, American tech companies are increasingly relying on nuclear power for their energy-intensive data centers. Microsoft already agreed in 2024 with Constellation to restart a reactor at Three Mile Island, and Google concluded a supply agreement in the same year with reactor developer Kairos Power.

Expanding existing facilities is considered faster and more cost-effective than building new reactors. Calvert Cliffs already has the necessary infrastructure and permits. According to Constellation, the additional 190 megawatts are scheduled to come online between 2030 and 2032.

Outlook and open questions

Constellation Energy plans to use the capital from the Amazon deal not only to increase capacity in Maryland but also to invest in new nuclear technologies. Dominguez mentioned "advanced nuclear technologies" as a possible investment target without providing details. This could refer to Small Modular Reactors (SMR), smaller reactor units that are more flexible than conventional large reactors.

For Amazon, the contract is part of a larger plan for decarbonization. The company has committed to becoming carbon-neutral by 2040. Data centers are among the company's largest electricity consumers. In addition to nuclear power, Amazon also invests in solar and wind projects, which, however, have fluctuating generation output.

Whether other tech companies will conclude similar long-term contracts with nuclear operators remains to be seen. The announcement by Amazon and Constellation is likely to reignite the discussion about the role of nuclear power in the energy transition.