Thirty years ago, the United States experienced the worst nuclear plant accident in American history. Since that time, increased vigilance in safety has made the nation’s 104 nuclear plants – including the 12 reactors operated by Entergy Nuclear – an even stronger and safer form of energy generation.
“What happened 30 years ago at Three Mile Island served as a call to action for everyone in the nuclear industry,” said Mike Kansler, chief nuclear officer for Entergy Nuclear. “Although there were no ill safety effects to the public or plant workers, we made it our business to learn from the event. It made us safer and more secure. It made us better.”
The incident, which occurred on March 28, 1979, tested the built-in safety systems of Three Mile Island Unit 2 in Middleton, Pa., in a real-world event. Those plant safety systems performed as designed, resulting in no injuries and no deaths, even as the reactor experienced the nation’s only partial meltdown, a condition that can occur when fuel is not properly cooled.
Although human error worsened the situation when a malfunctioning valve went undetected, the huge containment structures made of steel-reinforced concrete did as their name suggests – they contained the accident, preventing radiation from escaping into the atmosphere.
“At least a dozen epidemiological studies conducted over the past three decades by various agencies and universities concluded that any amount of radiation released during the incident was too small to result in health effects,” Kansler said. “But that’s not good enough. This event should never have happened in the first place. It’s our business to make sure it doesn’t happen again.”
The nuclear energy industry learned many lessons from the incident, Kansler noted. Both Entergy Nuclear and the nuclear industry have implemented those lessons over the past three decades for drastic improvements to an already safe record, and 51 reactors (roughly one-half of all in the United States today) have been built since.
Today, some of the most significant improvements result from training reforms for plant staff. Operators today are trained in procedures and taught to understand how to respond to situations that might take them beyond the bounds of those procedures.
Each Entergy Nuclear plant training facility includes a simulator that replicates a nuclear control room, allowing operators to learn and be tested on various scenarios that fall outside of normal operations.
In addition, many changes facilitated by the Nuclear Regulatory Commission in the past 30 years have increased the redundancy of plant equipment, meaning that if a system fails, it will have a backup ready to take over immediately.
When it comes to safety, added layers of protection only enhance nuclear energy’s capability to provide clean, efficient power, with performance levels increasing steadily over time. In 2008, U.S. nuclear plants surpassed coal, natural gas, oil and all other fuels that make electricity by operating to more than 90 percent of their total rated capacity. Nuclear plants also generated approximately 805.7 billion kilowatt-hours of electricity last year, enough to serve the total year’s electricity needs of one-fifth the U.S. population.
In fact, as a whole, the nuclear energy industry provides a safer working environment than a typical office setting, according to the Occupational Safety and Health Administration. Entergy Nuclear takes that standard to an even higher level. Of the nine nuclear plants owned by Entergy, all but two are certified under OSHA’s prestigious Voluntary Protection Program, which recognizes the highest levels of safety commitment at an industrial work site. Entergy’s remaining two plants – Palisades and dual-unit Indian Point Energy Center – are in the process of applying for VPP status as well.
As performance levels have improved with sweeping improvements to emergency response planning, training, radiation protection and other areas of nuclear operations, utility companies have made new investments in the construction of new commercial nuclear plants.
These new plants will have designs that build on the safe features of current reactors. The NRC says it expects to receive applications for 34 new nuclear reactors through 2010, and many states are now reviewing options to ensure the best possible ratepayer prices in preserving the ability to enhance their current nuclear output.
Entergy Corporation is an integrated energy company engaged primarily in electric power production and retail distribution operations. Entergy owns and operates power plants with approximately 30,000 megawatts of electric generating capacity, and it is the second-largest nuclear generator in the United States. Entergy delivers electricity to 2.7 million utility customers in Arkansas, Louisiana, Mississippi and Texas. Entergy has annual revenues of more than $13 billion and approximately 14,700 employees.