Lessons from Japan used at U.S. plants

Think the days of nuclear energy in Florida are numbered? Not so fast. Our need to produce electricity from a balanced mix of clean energy sources will keep nuclear energy in the limelight for decades to come.

But in the wake of the accident at Japan's Fukushima nuclear plant, the U.S. nuclear industry knows it must engage in a thorough reassessment of the safety risks from producing nuclear energy.

Although U.S. nuclear plants have an excellent safety record, and have shown they can withstand the potential consequences of a killer hurricane, as the Turkey Point plant did when Hurricane Andrew knocked out power to the plant for five days in 1992, utilities here at home are taking the Japanese experience very seriously.

The response to the Fukushima accident illustrates this: Already, safety changes have been made at Florida's five nuclear reactors (FP&L's St. Lucie Units 1 and 2, FP&L's Turkey Point Units 3 and 4, and Progress Energy's Crystal River plant) as well as at other U.S. nuclear plants. The Nuclear Regulatory Commission directed electricity companies to test their plants' emergency diesel generators and to make sure reactors have adequate backup power to withstand the effects of natural disasters from multiple sources. And the NRC almost certainly will order further safety measures as it draws the necessary lessons from Japan's accident.

All of the evidence so far shows that the Fukushima reactor problems were caused not by their age or condition, but rather from a failure outside the reactor system — a disruption, due to the earthquake and tsunami, of electric power supply needed to pump water to cool the fuel rods. The concrete and steel containment domes around the reactors withstood the force of the quake and tsunami — a testament to their robustness, but it was a loss of power that led to the explosions and partial meltdowns.

Here at home, one of the questions arising from the Japanese accident is whether nuclear reactors being built in the United States will be safe. The NRC is currently weighing certification of Westinghouse's AP1000 reactor. That decision, originally expected for late this summer or early autumn, may be delayed to give regulators more time in view of the Japanese accident.

The Westinghouse design, if approved, would be used for the first new nuclear plants to be constructed in the United States in more than 30 years. Progress Energy has contracted with Westinghouse and the Shaw Group for two AP1000 reactors to be built in Lee County.

The AP1000 is safer than the disabled reactors in Japan, because in the event a coolant pipe breaks, it is designed to shut down safely without relying on electricity, diesel generators or pumps. Instead, the reactor relies on gravity to circulate water and compressed gas to keep the core from overheating.

Safety would be enhanced at operating reactors if spent fuel rods currently being stored in engineered water pools at nuclear plant sites are shifted to concrete-and-steel dry casks and eventually transported to an interim storage facility until construction of a deep-geologic repository at Yucca Mountain in Nevada is completed.

Because of the horrible accident in Japan, it is easy to dismiss nuclear technology as a failure, but that would be the wrong lesson to draw. The Three Mile Island accident in 1979 obliged the U.S. nuclear industry to make a number of changes in plant design and operation, which led to a significant improvement in the safety and performance of nuclear plants in the United States. Today American nuclear technology exceeds anything available elsewhere.

Yet there are those politicians and some environmental groups prepared to forgo nuclear energy. This would be wrong. No technological system is immune to accident. Antinuclear critics should consider the staggering costs in industrial accidents, health effects, quality of life, environmental damage and long-term risk from the pursuit of fossil fuels. Eleven people were killed when the Deepwater Horizon oil rig exploded in the Gulf of Mexico a year ago, and the ensuing oil spill was one of the worst environmental disasters in U.S. history.

No one thought of ending coal mining after the deaths of 29 miners at the Upper Big Branch coal mine in West Virginia. Fossil fuels also have the hidden costs of climate change.

I believe we will go forward and build more nuclear plants. Now, more than ever, we must do everything possible to keep our nation's and Florida's economy strong. It will not happen if we fail to provide enough base-load electricity for households, businesses and industries. For the sake of our environment as well as security, much of our electricity should come from nuclear energy.

Jack Ohanian is professor emeritus of Nuclear and Radiological Engineering at the University of Florida.

Lessons from Japan used at U.S. plants 04/17/11 [Last modified: Sunday, April 17, 2011 5:30am]

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