Florida nuclear plants to shut ahead of Hurricane Irma

[Rhiannon12866]

(Reuters) - Electricity generator Florida Power & Light said on Thursday it will shut its two nuclear power plants before Irma comes ashore as a very powerful hurricane.

FPL, a subsidiary of NextEra Energy Inc, generates enough power for about 1.9 million homes at the Turkey Point and St. Lucie plants, which are both along Florida’s Atlantic Coast, about 20 feet (6 meters) above sea level.

“We will safely shut down these nuclear plants well in advance of hurricane-force winds, and we’ve finalized plans for that shutdown,” FPL spokesman Rob Gould told a news conference.

The company will adjust the plans as necessary, “depending upon the path of the storm,” Gould said. He would not comment on exactly when the plants would be taken down or how long they could be shut.

More: http://www.reuters.com/article/us-storm-irma-nuclearpower/florida-nuclear-plants-to-shut-ahead-of-hurricane-irma-idUSKCN1BI2IA?il=0

[SHRED]

1. What cools them if they are shut down?

If they lose power??

[Rhiannon12866]

2. I'm hardly an expert on nuclear, but these precautions were mentioned in the article:

Fortunately, we learned from Fukushima.


Gould said FPL might have to turn off some substations ahead of any major flooding, a technique that could help the company restore power faster once any floodwaters recede, rather than keeping them on and allowing the storm to damage them.

FPL’s nuclear plants are protected by thick concrete and reinforced steel and like many plants around the world were bolstered further after the 2011 Fukushima nuclear disaster in Japan, Gould said.

A series of explosions and meltdowns occurred at the Fukushima nuclear plant after a massive earthquake unleashed a powerful tsunami that shut the facility’s cooling systems and led to meltdowns.

[Ghost Dog]

3. Without power to a nuclear power station?

I think that's called... Going critical.

[FBaggins]

4. Backup power

They generally shut down a reactor a day prior to the expected arrival of hurricane-force winds. This isn't because the winds would be expected to directly harm the reactor, but because of the transformers and other transmission equipment that connects them to the grid (in both directions). Losing either outgoing connection to the grid or incoming grid power supply forces them to shut down... and a hurricane has a greater chance of damaging transmission equipment.

In the later case (losing grid power to the plant), they would have to use multiple redundant backup generation to run the pumps that cool the reactor. Depending on the specific reactor, there are probably one or two additional options for cooling. In newer designs, cooling is often possible without power.