UPDATE 1-Duke to retire Florida Crystal River nuclear plant

Feb 5 (Reuters) - Duke Energy Corp, the biggest power company in the United States, said Tuesday its Progress Energy Florida utility will retire the Crystal River nuclear plant in Florida.

The plant has already been safely shut down and offline since late 2009 due to damage done to the reactor's containment structure during a power upgrade and the replacement of the unit's steam generators.

The company said in a release it is reviewing alternatives to replace the power produced by the reactor, including the potential construction of a new natural gas-fired plant. The company said it is evaluating potential sites for new plant capacity that may be needed in the future to meet Florida customer needs.

Duke said the four coal plants at Crystal River with a capacity of 2,291-megawatts (MW) will remain in service. The reactor had a capacity of 860 MW.

"We believe the decision to retire the nuclear plant is in the best overall interests of our customers, investors, the state of Florida and our company," Jim Rogers, CEO of Duke Energy said in a release.

"This has been an arduous process of modeling, engineering, analysis and evaluation over many months. The decision was very difficult, but it is the right choice," Rogers said.