Florida Power and Light is closing two nuclear plants along the state's Atlantic coastline ahead of Hurricane Irma, the company said Thursday, Sept. 7.

FPL Public Information Officer Rob Gould said FPL's Turkey Point and St. Lucie nuclear generators will be powered down. Other non-nuclear plants are expected to generate enough to power to make up for losses from the nuclear plants closing unless they are severely damaged by the storm.

FPL is the third-largest electric utility in the U.S. and serves nearly 10 million people in the southern half of Florida.

Some customers could be without power for weeks if Irma's "worst fears are realized" and FPL has to rebuild the electrical system instead of just repairing it, Gould said. "There is simply no way to hurricane-proof an electrical system. It's virtually impossible," Gould added.

"No grid is designed to be able to withstand a category 5 storm that has been approaching 180 or 185 miles per hour," Gould said. "It's just not practical."

But since 2005, FPL has invested $3 billion in strengthening its electrical grid with updated technology and new underground lines. The nuclear facilities in particular are "among the strongest in America and arguably in the world," Gould said.

Gould made it clear that Floridians should expect to be without power for at least some time, but how long power will be off is unclear. FPL started preparing for the storm "well over a week ago," Gould noted.

"We are probably more ready than we have been for any other storm in our company's history," Gould said. FPL has "virtually a small army" of 11,000 extra linemen coming to the service areas expected to be hit hardest by Irma's damage, primarily in the Miami-Dade area.

One of Irma's biggest threats to Florida is that the storm's path is somewhat unclear and damaging winds could spread across the state. Some supplementary crews are staying put along the Gulf coast and in the northern parts of Florida should the storm change path and centralize damage there instead.

The Turkey Point nuclear generating station, located near Homestead, Florida, south of Miami, withstood the impact of Hurricane Andrew in 1992 as the eye of the storm passed over the facility. Andrew was the last storm that made landfall in Florida as a Category 5 hurricane.

Turkey Point nuclear facility.
Turkey Point nuclear facility.

Hurricane Andrew cost FPL's Turkey Point station about $90 million in damages as facilities around the nuclear reactor that were touted as hurricane-proof took serious beatings, according to the Miami Herald. Andrew -- and its more than 17-foot storm surge -- left Turkey Point running on backup generators for more than a week as the reactor was cooled following a shutdown. But no nuclear components were harmed by Andrew's damage.

The St. Lucie power plant is nearby, located on the coast between Melbourne, Florida, and West Palm Beach, Florida. St. Lucie wasn't in as direct of a path of Andrew as Turkey Point was, but the reactor withstood Hurricane Frances in 2005 and Hurricane Wilma in 2006.

It took weeks -- and in some places months -- to rebuild the power grid after Hurricane Andrew, Gould said. In some homes, a complete leveling of the structure means that even if FPL is ready to restore power, there's no house to restore it to.

St. Lucie nuclear plant.
St. Lucie nuclear plant.

The nuclear reactors at Turkey Point and St. Lucie will remain offline until it's safe to restore crews and generation. The plants will undergo thorough inspection ahead of returning to power and all evacuation routes will be cleared of debris.

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