CALLAWAY COUNTY, Mo.—The 31-year-old Callaway Energy Center is doing some heavy lifting.

Missouri’s lone nuclear power plant produces 11.7 percent of the state’s electricity from one reactor cranking out 1.2 gigawatts, making it the third-largest electricity producer in the state. Its 553-foot-tall, cloud-spewing cooling tower is the second-tallest structure in Missouri behind the St. Louis Arch, two hours’ drive east.

Operated by Ameren Missouri, Callaway’s Westinghouse four-loop pressurized water reactor provides electricity to 1.2 million customers. The $3 billion facility puts more than 800 employees and contractors to work.

In the humming reactor control simulation room, with tan walls filled with dials, knobs, switches, lights and monitors, Barry Cox, senior director of nuclear operations at Callaway, explains that engineers train to make the plant withstand earthquakes, tornadoes and human error. But most of the indicator lights are off and the room is quiet, save the sounds of ventilation.

“This is what it’s like in the plant at night, 2 o’clock in the morning,” he says.

Engineers are working to keep up the steady, if boring, plant operations, especially since the Nuclear Regulatory Commission extended Callaway’s license last year to run until 2044.

“We are a baseload plant,” Cox says. “About 3,565 megawatts thermal and about 1,283 MW electric go out onto the grid. So it’s about 30 percent efficiency from what I have to produce inside the core from a heat point of view to what I get out on the electric grid, and that’s typical for all steam-producing plants.”

But Callaway really flexes its muscles when it comes to zero-carbon-emissions energy in a coal-heavy portfolio. Missouri gets 82 percent of its electricity from coal, and the recently bankrupt Peabody Energy Corp., the nation’s largest coal company, is based in St. Louis.

The U.S. Energy Information Administration reports that Missouri ranks 13th in total greenhouse gas emissions in the United States. Wind, solar, biomass and hydroelectric power provide the state with just 2.2 percent of its electricity. That means 83 percent of Missouri’s carbon-free energy comes from Callaway.

Many analysts are now calling not just to preserve existing nuclear power plants, but to invest in new designs to help fight climate change. “A new round of innovation for nuclear reactors would be quite important,” said Energy Secretary Ernest Moniz last month.

Across the United States, nuclear provides 20 percent of all electricity and more than 60 percent of greenhouse gas-free electricity. But some plants have already shut down ahead of schedule, and others may do so, as well, not because of environmental opposition but because of market forces.

“In the United States today, we have some older plants shutting down,” Moniz said. “The pattern is obvious: It’s principally plants in competitive markets faced with very low natural gas prices.”

A clear role in the Clean Power Plan

Nuclear energy’s clean bona fides may be its saving grace in a wobbling global energy market that is trying to balance climate change ambitions, skittish economies and low prices for oil and natural gas. Many countries are wrestling with the nuclear option as stalwarts like France tap the brakes, Japan uneasily presses on and China drops a cinder block on the gas pedal.

Some nuclear advocates argue that in the climate fight, nuclear energy deserves many of the same considerations as wind, solar and other renewable energy. Callaway and 98 reactors like it in the United States are facing an identity crisis over whether they count as clean. In a country about to go on a strict carbon diet, the nuclear energy industry wants to make sure it’s still on the menu.

However, sticker shock and staunch public opposition continue to haunt the nuclear industry, and other nations are watching the sector closely to see whether they should make billion-dollar investments in reactors to fight climate change and grow their economies.

“Nuclear is without a question the most important environmental technology in the 21st century,” said Michael Shellenberger, an advocate for nuclear power and president of Environmental Progress.

He said nuclear is the highest rung on the energy ladder that civilizations climb as they move to denser fuels from biomass, to coal, to oil, to gas and finally to uranium. “From an energy and environmental and development perspective, I want everybody to go up the hierarchy of energy,” Shellenberger said.

Under U.S. EPA’s Clean Power Plan to reduce emissions in the power sector, new nuclear power plants and reactors upgraded to produce more power count toward states’ carbon goals.

“The language in that rule is very explicit about the role that nuclear can and should play in mitigating against climate change going forward,” said John Keeley, a spokesman for the Nuclear Energy Institute. “We’re really, really excited about that.”

The Clean Power Plan requires Missouri to lower its emissions by 36.7 percent by 2030. The state was one of 27 that filed lawsuits against the rule, and pending legislation may block funding for compliance plans (ClimateWire, April 28).

A reactor that doesn’t need ‘babysitting’?

According to the Missouri Department of Economic Development, the state spent $6.7 billion on electricity generation in 2010. The weighted average price of electricity across economic sectors in Missouri ranked the state 34th in the country.

Keeping the nuclear option open would take a massive bite out of carbon pollution, and a growing cohort of environmental activists is pushing to make this happen. Unlike wind and solar power, nuclear can run at full blast almost all the time while emitting zero carbon dioxide.

The nuclear industry would also like recognition for existing nuclear power plants as a bulwark against climate change, arguing that states should count nuclear energy toward their renewable portfolio standards and afford them the same tax incentives and subsidies as renewables.

Momentum is building for nuclear energy in some parts of the world, with China leading the charge. The country has 32 nuclear reactors online, 22 under construction and more in the planning stages, putting it on a trajectory to hit 150 GW of nuclear power generation by 2030.

In 2012, the Nuclear Regulatory Commission approved the first new reactors in the United States in 30 years. Among students in the country, nuclear engineering is becoming a more popular major (ClimateWire, Dec. 15, 2014).

The renewed interest in nuclear energy has led to startup companies developing “fourth-generation” reactor designs that are walkaway safe, meaning that if left unattended, they safely coast to a halt.

“All three generations of nuclear technology that are out there today require babysitting,” said Microsoft co-founder Bill Gates during a panel last month in Washington, D.C. “The nuclear industry has never designed an inherently safe product.”

Gates is the largest investor in TerraPower, a nuclear energy firm that’s developing a reactor that runs on depleted uranium, a waste product of the enrichment process used to make fuel for conventional reactors, yielding a fiftyfold gain in fuel efficiency.

He acknowledged, however, that it may take a long time for new reactors to gain enough traction to start making a dent in global greenhouse gas emissions. “We’re moving faster than anybody ever has in that space, but that’s about a 30-year period, assuming things go really well,” Gates said.

Nuclear advocates eye many power sources

Other companies, like NuScale Power, are developing small modular reactors. Rather than building one-of-a-kind, billion-dollar, gigawatt-scale plants, NuScale is proposing a reactor with a smaller output fabricated on an assembly line and dropped in place. The smaller scale means lower upfront costs, and mass production would lead to economies of scale.

“To me, what may end up being the most important thing is if this is an attractive technology, the capital requirements and financial structures are so different that it opens up the geography” to other markets that don’t have billions to spend, Moniz said. “This year, we expect that NuScale will be submitting a design certification application to the Nuclear Regulatory Commission. It’s for a roughly 50-MW reactor.”

However, existing reactors are tacking into the wind, in terms of economics and politics. Vermont independent Sen. and Democratic presidential hopeful Bernie Sanders has laid out a plan to decommission every reactor in the United States.

Nuclear supporters warn that letting aging reactors wither would harm the fight against climate change as coal- and natural-gas-fired generators ramp up to fill the gaping void. The 2012 shutdown of the 2 GW San Onofre nuclear plant in California raised generation costs by $350 million the following year, and carbon dioxide emissions in the state increased by 9 million metric tons, the equivalent of putting 2 million more cars on the road.

Mark Jacobson, an energy researcher at Stanford University who found that it’s feasible for much of the world to run on wind, water and sunlight, acknowledged that nuclear energy has some carbon benefits but said it has an insurmountable drawback of opportunity costs, namely the billions of dollars needed upfront and the decades it takes to plan and build reactors.

“If you’re looking at just one technology in isolation, maybe you don’t care about that opportunity cost,” he said. “But when you’re comparing the two technologies, that becomes relevant. If you have $1 to spend, would you rather spend that on nuclear or wind?”

But the nuclear industry isn’t arguing to be the only option on the table, saying instead that it wants to be an appetizing entree in a buffet of energy options to fight climate change.

“You don’t want to go all in on any one technology,” said NEI’s Keeley. “And NEI is pretty clear about that, too. We see a role for renewables. We see a role for natural gas. We see a role for nuclear.”

Reprinted from Climatewire with permission from Environment & Energy Publishing, LLC., 202-628-6500