By Laila Kearney

NEW YORK, Jan 24 (Reuters) - NextEra Energy NEE.N has spoken with regional grid operators and filed notice with federal regulators about a possible restart of its Duane Arnold nuclear power plant in Iowa, the company's CEO, John Ketchum, told Reuters on Friday.

After decades in decline, U.S. nuclear power has become a highly-desired electricity source for Big Tech's AI data centers. Nuclear's ability to supply vast quantities of around-the-clock energy that is virtually carbon-free has boosted shares of nuclear power plant companies over the last year.

"We are very excited about the way Duane Arnold is moving forward," Ketchum said.

No fully-shut U.S. nuclear reactor has been brought back to life, but Duane Arnold would be among three plants in the country in the process of attempted restarts. One of the sites - Constellation Energy's CEG.O Three Mile Island plant, which is being renamed Crane Clean Energy Center, in Pennsylvania - secured a power purchase agreement to deliver power from the plant for Microsoft MSFT.O data centers.

The roughly 600-megawatt Duane Arnold Energy Center, which shut in 2020 after operating for 45 years, would likely also feed power to data centers, Ketchum said, though no contracts have been signed.

The facility has undergone an initial engineering assessment, which found the plant's reactor is in strong shape and the broader plant could be restored to operations by as early as late 2028.

Duane Arnold cooling towers, which were destroyed in a powerful wind storm, will need to be rebuilt, Ketchum said, adding he expects construction to be straightforward and not require nuclear expertise.

There is also work to be done on transmission, and equipment for the site has not been ordered, he said.

Two near-term milestones on potentially restarting Duane Arnold include a detailed analysis and inventory of the site's condition and securing a customer to buy power from the site, he said.

(Reporting by Laila Kearney; Editing by Rod Nickel)

((Laila.kearney@thomsonreuters.com; (917) 809-0054;))