At age 44, the Oyster Creek power plant on the coast of New Jersey is the oldest operating nuclear reactor in the country. Like a lot of fortysomethings, it’s starting to show signs of age. Rust has severely damaged the reactor’s steel radiation barrier. Workers at the site discovered that tritium, a radioactive form of hydrogen, was leaking from underground pipes. And state regulators said that to keep its operating license, the plant’s owner, Exelon, would need to install costly new cooling towers. Instead, Exelon opted to pull the plug. Oyster Creek is now scheduled to close in 2019, taking 630 megawatts of electricity—enough to power 600,000 homes—off-line.
Oyster Creek will be one in a wave of recent nuclear shut-downs. On Friday, Southern California Electric announced that it will shut down the San Onofre nuclear power plant, which powered 1.4 million homes in San Diego County. Last month, the Kewaunee nuclear power plant in Wisconsin was shut down after its owner, Dominion, concluded that it could no longer operate it profitably. In February, Duke Energy announced that it would close the Crystal River 3 nuclear power plant in Florida, after determining that it would be too expensive to upgrade the plant's equipment.
In the coming years, as the rest of the aging U.S. nuclear fleet starts to push 50, 60, and beyond, worrisome questions will arise. How long can nuclear facilities operate safely or economically? If more of the country’s 104 nuclear-power plants go down, where will the electricity to replace their output come from? And without a steady supply of nuclear power—the largest source of zero-carbon electricity—how can the U.S. meet the rising energy demands of a growing economy without emitting vast new quantities of the carbon pollution that causes global warming?
“It’s an important question about our energy future,” said John Deutch, a former director of energy research at the Energy Department and the coauthor, along with Energy Secretary Ernest Moniz, of an influential report, “The Future of Nuclear Power,” from MIT. “This will become a progressively larger question in terms of U.S. electricity capacity.”
Nuclear power is a cornerstone of the nation’s energy mix. It generates 20 percent of our electricity, and it’s the only major form of energy that doesn’t emit carbon pollution. To be sure, renewable-energy sources such as wind and solar power are growing rapidly—but, combined, they still supply only about 5 percent of the nation’s electricity. And renewables are intermittent. They produce power when the sun shines or the wind blows. Only nuclear generates cheap, reliable electricity all day and all night, no matter the weather.
Most of today’s plants were built during America’s love affair with nuclear power in the 1960s and 1970s; they were granted 40-year operating licenses. But orders for new U.S. plants froze after the Three Mile Island nuclear meltdown in 1979. Over the past few years, 73 of the nation’s existing plants have reached the end of their 40-year operating spans but have been granted 20-year renewals.
However, even if those plants keep operating safely, the United States will need more nuclear power to maintain current of supplies of zero-carbon energy. National electricity demand will increase 28 percent by 2040, according to the Energy Department. For nuclear power to keep supplying 20 percent of that electricity, the industry would need to build about 25 reactors by 2040, according to the Nuclear Energy Institute, an industry advocacy group. But that almost certainly won’t happen.
As the urgency of global warming grows, interest in nuclear power is reviving. Five U.S. reactors under construction are set to come on line in the next decade. But it’s not expected that many more will be built. The economics simply don’t make sense. Building a nuclear facility is an expensive proposition, fraught with legal and insurance liability. It costs $5 billion to $20 billion and can take a decade to complete a plant, compared with the $1 billion to $3 billion and one to three years that it takes to build coal- or natural-gas-powered plants. “The new reactors being discussed will not be enough to offset capacity reduction from those that are being retired,” Deutch said.
In the coming years, as electricity demand grows and more nuclear plants shut down, the bulk of that capacity is likely to be filled by coal and natural-gas plants. Of course, replacing a fleet of zero-carbon energy plants with a fleet of carbon-polluting energy plants could significantly increase U.S. fossil-fuel pollution at a moment when the majority of scientists say it’s essential to do the opposite to stave off catastrophic global-warming scenarios.
Meanwhile, electric utilities want to squeeze as much life as they can out of existing nuclear plants. “We treat every one of our plants like we want them to run as long as possible,” said Rick Rhodes, a spokesman for Duke Energy, based in Charlotte, N.C. The company owns 11 nuclear-power plants; the oldest, Robinson, in Hartsville, S.C., is 42. “It’s a weakness of our industry,” he said. “We don’t have any option but to do that.”
Nuclear-safety advocates agree. “Aging can cause nuclear plants to be compromised,” said David Lochbaum, director of the Union of Concerned Scientists’ Nuclear Safety Project. “Nuclear-power plants are like cars. Not all the parts can be expected to last a lifetime. The key to safety is to monitor and replace them before they break down. That costs money. The temptation for some companies is to defer things to a later date. Aging represents another opportunity to fail.”
Owners of nuclear-power plants over 40 that have received 20-year license renewals are looking ahead to what will happen when the plants hit 60. In the absence of a wave of new nuclear power, utilities say they hope they can keep the plants running, by diligently updating materials and equipment.
For now, it’s unclear how long they can do that—and what happens when they can’t. As John Keeley, a spokesman for the Nuclear Energy Institute, said, “One area of uncertainty will be, is there life after 60?”
CORRECTION: An earlier version of this story misspelled Ernest Moniz's name.