Utility power generation producer Constellation is entering into a 20-year power purchase agreement (PPA) with global tech giant Amazon to support the continued operation and expansion of the Calvert Cliffs Clean Energy Center nuclear plant in Lusby, Maryland.

The long-term deal reportedly will enable more than $3 billion to upgrade the 1,790-MW Maryland nuclear plant’s infrastructure. Including roughly 190 MW of new, emissions-free generating capacity through plant uprates coming online between 2030 and 2032.

Both parties have also reportedly finalized a retail supply agreement to match consumption Amazon operations across the 13-state PJM market. Constellation emphasized that all of the electricity generated by the Calvert Cliffs plant will continue to flow into the main grid interconnection.

While most corporate PPAs don't power the company directly, that investment in renewables or nuclear power can bring more carbon-free energy onto the overall grid.

“This agreement demonstrates how private investment can strengthen critical energy infrastructure,” said Constellation CEO Joe Dominguez in a statement. “Amazon’s commitment supports the long-term operation of Calvert Cliffs for generations to come and creates a strong foundation for future investment in both the facility and in advanced nuclear technologies.”

The sustained revenue stream enables Constellation to meet its commitment to relicense the plant for another 20 years.

The Calvert Cliffs Clean Energy Center is Maryland’s only nuclear plant and generates roughly 80% of the state’s carbon-free energy. It contains two pressurized water reactors capable of delivering 1,756 MW combined.

In 2025, Constellation invested $100 million in the Calvert Cliffs power plant on the western shore of the Chesapeake Bay as the eastern U.S. power generation owner and operator increasingly banks on America’s renewed focus on nuclear energy. 

For Amazon, this PPA will also help the company manage its volatile energy costs for regional data centers and facilities through locking in a predictable price per MWh rate over the 20-year period.

“Amazon is committed to investing in carbon-free energy to strengthen the grid and benefit the communities where we operate," said Kerry Person, vice president of Amazon Web Services (AWS) global operations and data center delivery. "This long-term agreement with Constellation sustains the continued operation and expansion of Maryland's largest source of carbon-free energy, supports hundreds of jobs and brings significant new generation to the regional grid.”