FPL mystery: How did small fire knock out power to millions?
Feb 27, 2008
South Florida Sun-Sentinel--Feb. 27, 2008
By John Holland and Julie Patel
It took only three minutes for an overheated switch and then a fire at a power substation near Miami on Tuesday afternoon to shut down a nuclear plant south of the city and trigger Florida’s largest blackout in at least 20 years. Figuring out why is going to take longer.
Florida Power & Light Co. executives said they can’t explain how malfunctions at a substation triggered a domino effect that left at least 2.5 million Floridians without power and affected 20 electrical substations as far away as Daytona Beach and Tampa. Internal controls should have kept the outages from spreading so quickly and that far, company officials said.
“We still don’t know why that didn’t work,” FPL President Armando Olivera said.
Company officials do have a grasp on the sequence of events, tracing it from an overheated voltage switch and subsequent fire at the Miami-Dade County substation at 1:08 p.m., to a precautionary and automatic shutdown of the Turkey Point nuclear power station.
“These types of fires are initiated by what amounts to a short circuit, not unlike a short circuit you’d see at your own household,” Olivera said. “Typically a disconnect switch failing by itself would not cause these type of widespread problems.”
The power failure began at the substation at Flagler and 92nd Avenue in Miami-Dade and soon affected “virtually the whole state,” Olivera said. At its peak, more than 1 million electricity customers from all Florida utilities were without power. Most of the outages were in Miami-Dade and Broward counties. Lights started coming on in most areas within an hour, and by 4:30 p.m. virtually everyone had power restored.
While FPL officials said they were surprised by the cascading outages, energy experts said it’s common for a shutdown at one substation to ripple to others.
“If you don’t, you could have a small problem become a very major problem really quickly,” J.R. Kelly, public counsel with the Committee on Public Service Commission Oversight. By shutting down quickly, the substations averted potentially far more lasting damage, he said.
But Mike Bedley, a partner with Fort Lauderdale-based energy consulting firm Apex Power Services Corp., said FPL isn’t off the hook yet.
“The good news is that they were safely shut down and we can give them some credit for that,” Bedley said. “But there are some questions. … Did that many plants need to be tripped offline or were there other errors that caused more units to shut down?”
Bedley also said FPL may want to look into whether it was doing enough to maintain its equipment, especially on a day with relatively low demand for electricity. “How did the switch get overheated when it wasn’t a hot day?” he said.
One minute after computer systems detected the fire, two generators at the Turkey Point nuclear power plant in south Miami-Dade County began shutting down as an automatic safety measure, FPL nuclear chief Art Stall said. With the generators off, power began going out across Florida almost immediately.
The result was the biggest outage the company has experienced since at least the 1980s.
“If you get a big imbalance between your demand and your ability to meet that demand …. [the power grids] begin to turn people’s lights off,” Olivera said.
The day’s events caught the attention of environmental groups and others opposed to FPL’s concentration of energy production in huge power plants like Turkey Point.
“Aside from the safety concerns about nuclear power, there’s a real problem when you have huge areas of the state depended on two or three of these huge facilities,” said Stephen Smith, executive director of the Southern Alliance For Clean Energy, an environmental advocacy group that has questioned FPL’s plans for new nuclear power plants in Florida.
The Federal Energy Regulatory Commission, which has responsibility for electricity grid reliability, said it wants to know whether there were any violations of federal grid reliability rules.
Olivera said he can’t rule out human error or anything else at this point.
“In the coming hours and days we will conduct an extensive investigation of everything,” Olivera said. “We have to look at this objectively and look at all possibilities.”