Nuclear Power

Poised For Rebirth

By Cynthia Washam

“NO NUKES!” was once the battle cry of environmentalists, but with concerns about global climate change and new nuclear power plant designs, you’re more likely to hear today’s environmentalist holler, “MORE NUKES!”

The phrase “Atoms for Peace” seems as much a part of 1950s nostalgia as saddle shoes and sock hops. But like most ideas of the past, the vision that President Eisenhower had of nations sharing nuclear technology to generate electricity, rather than weapons, is becoming relevant once again as the world embarks on a new era of nuclear-power generation.

The Vienna-based International Atomic Energy Agency expects at least 60 new nuclear plants to be built worldwide within the next 15 years, and many more later. The worldwide demand for electricity is expected to surge 75% between 2000 and 2020. China and other developing industrial countries will be at the forefront of the growing need.

Here in the United States, a nuclear plant hasn’t been licensed since 1984. Yet 16 power companies in the past couple of years have indicated an interest in building up to 25 new nuclear plants. The first ones are expected to start lighting our homes around 2016.

“I think we’re looking at a real rebirth in the industry,” says J. David Robertson, associate director of the research reactor at the University of Missouri and 2006 chairman of the ACS Division of Nuclear Chemistry and Technology. “Every indication is that the industry is ready to build some more.”

The Bubble Bursts

The excitement that ushered in nuclear power’s first wave soon abated as utilities realized that this new source of electricity came at a high cost. A 1000-megawatt (MW) plant costs up to $2 billion to build, 2.5 times the cost of a natural-gas plant with the same output. Twenty years after Eisenhower’s 1953 Atoms for Peace speech before the United Nations, domestic utilities stopped planning nuclear plants, instead sticking with natural gas and coal.

That move was fine with the public, which had grown wary of nuclear power. A partial core meltdown at the Three Mile Island plant near Harrisburg, PA, in 1979, confirmed their fears. Radiation released during the mishap was well below levels associated with health effects, yet high enough to scare the public. Support for nuclear power after the incident dropped precipitously. “Three Mile Island was a huge financial loss for the industry, and it pointed out its weaknesses,” says Harold McFarlane, president of the American Nuclear Society and deputy associate lab director for nuclear programs at the U.S. Department of Energy’s Idaho National Laboratory.

Concerns that might have abated a few years after Three Mile Island were rekindled in 1986, when a reactor exploded at the Chernobyl nuclear plant in the Ukraine, spreading a plume of radioactive fallout across the western Soviet Union, Europe, and as far east as the North American coast. Fifty people died from the explosion, and another 4000 died or are expected to die prematurely from radiation exposure. Two decades later, radiation is still too high for people to venture unprotected within a 30-square-kilometer area surrounding the plant.

With nuclear-plant construction in limbo, American power companies met their customers’ growing demand for electricity with new coal and natural-gas plants. These affordable fuels gave them little reason to seek other sources of power.

Nuclear plants, meanwhile, quietly upped their output by operating more efficiently. They’ve provided 20% of the U.S. energy supply through the past decade, even as six nuclear plants were decommissioned. Nuclear plants now operate at 90% of their capacity, higher than any other type of power plant.

Much of the power boost came from uprates. An uprate increases the flow of steam from the reactor to the turbine generator, raising electricity output up to 20%. Since 2000, the Nuclear Regulatory Commission (NRC) has approved more than 60 uprates, which has boosted output by almost 2800 MW.

The surge from uprates, though, is temporary. Nuclear plants in the United States are growing old. By 2015, 40% will face an end to their 40-year operating licenses. Extensions from the NRC can buy them another 20 years. By 2030, though, the Energy Department forecasts a 45% growth in energy use. Clearly, the country will need new power supplies.

Choice of Environmentalists

The idea that atomic power should meet that need was inspired largely by a group of scientists, engineers, nuclear operators, and activists convened by the Massachusetts Institute of Technology (MIT). The product of their efforts was the influential 2003 report, The Future of Nuclear Power: An Interdisciplinary MIT Study.

“We took people from very different disciplines and spent two and a half years together looking at integrative aspects of the issue,” says Ernest Moniz, the committee’s co-chair and MIT’s director of energy studies. “That started the dialogue among environmental groups, governments, industry, utilities.”

Moniz and his colleagues decided to study the future of nuclear power in light of the growing threat of global warming. A third of all greenhouse gases come from electricity generation. According to the Nuclear Energy Institute (NEI), the country’s 103 nuclear plants in 2005 spared us 682 million metric tons (t) of carbon dioxide (CO2 ), the output of 96% of the country’s passenger cars. A tripling of the world’s nuclear-power output by 2050 would save 1.8 billion t of carbon emissions from coal plants, the MIT study predicted.

“Nuclear, on a global basis, makes a contribution [toward abating global warming] by displacing CO2 emissions,” says Thomas B. Cochran, the director of the Natural Resources Defense Council’s nuclear program and a member of the MIT committee. Cochran is among a number of leading environmentalists guardedly supporting nuclear power as a means of stemming global warming. In a Washington Post editorial last April, Greenpeace co-founder Patrick Moore urged the country to embrace nuclear power. He considers it the only electricity source clean and reliable enough to replace coal.

Surprisingly, the environmental benefits that Cochran and Moore see in nuclear power have not registered with the public. Many Americans actually believe nuclear plants emit CO2. “Concern about global warming has so far been uncorrelated with support for nuclear power,” says Stephen Ansolabehere, an MIT political scientist and study participant. Ansolabehere conducted opinion polls on energy sources in 2002, 2003, and 2006. “Nuclear power has a relatively low level of support among all of the energy options—gas, oil, coal, wind bio, hydro, and solar.”

The Cost of Carbon

When the MIT group published its study four years ago, utilities had little reason to care how people felt about new nuclear plants; they couldn’t afford to build them no matter how much the public came to support them. However, nuclear plants would become economical, the MIT study proposed, if polluters had to pay for the carbon they emit.

The idea of taxing polluters and rewarding non-polluters has been tossed around for more than a decade. Proponents contend that businesses would limit their use of fossil fuels if they had to pay a high price for them. Some envision a tax on carbon emissions, possibly coupled with tax breaks for taxpayers using cleaner technology. Another scenario would involve carbon credits that companies could trade, so that a company could exceed its quota by trading credits with a company that releases less than its share.

“It’s the industry’s belief that there will be a carbon policy,” Moniz says. “A lot of members of Congress talk about it. The question is when and what structure it will take.”

The mere threat of carbon controls is likely to influence power companies’ choice of plants, says Richard Meserve, the president of the Carnegie Institution and a former NRC chairman. “Coal is still cheap, and coal plants have cheaper capital costs,” he says. “But a generating company has to anticipate they would operate a nuclear plant 40 years or longer. There’s a significant likelihood over that time period there will be carbon constraints. There’s a lot more certainty about the costs for a nuclear plant.”

A Push from Uncle Sam

Along with the carbon-tax threat, power companies now have several more concrete reasons for going nuclear. One is their dependence on foreign suppliers for natural gas. Natural gas in the 1980s became the darling of the industry. It was cheap and didn’t spew as much carbon as coal plants. But in the last decade, the cost of the once-cheap fuel jumped from $2 to $12 per thousand cubic feet. With little natural gas left to tap domestically, the United States is at the mercy of international vendors. “Gas prices are higher and volatile,” Moniz says. “Utilities don’t like uncertainty. The cost of operating a nuclear plant is stable and low.”

Natural-gas plants also are expensive to run. Producing 1 kilowatt-hour at a gas plant costs 6 cents. At a coal plant, it’s 2 cents, and at a nuke, 1.7.

To encourage nuclear-plant construction, the MIT group recommended tax credits for reactors with new, safer designs. Two years later, Congress passed the tax break, along with other construction incentives, in its Energy Policy Act of 2005. The act allows operators to take tax credits of 1.8 cents per kilowatt-hour for the first 6000 MW produced. It also offers loan guarantees to develop energy technology, including nuclear power, that reduces or avoids producing carbon emissions. Another perk for developers of new nuclear technology is federally underwritten insurance against regulatory delays and other unpredictable setbacks.

The act spurred a flurry of activity among power companies. Nearly 30 years since the last nuclear plant was licensed, 16 utilities are planning to build up to 25 new plants. “We’re going to see the costs of building the plants come down,” says spokesman Steve Kerekas of the Nuclear Energy Institute, an organization of plant operators. “Because the incentives favor the first folks to go through the process, it’s accelerated the applications.”

Not Your Grandmother’s Nuke

Cost savings also will come with the switch from yesterday’s unique plant designs to a generation of clones. Operators will choose new plants from several approved models. Standard designs will not only cut building and operating costs but also slash licensing time. The NRC has already approved four new designs and is reviewing several more.

Kerekas of the Nuclear Energy Institute says that he expects most new plants to spring up alongside old ones. “You’ve got your infrastructure in place,” he says. “You’ve got your community relations in place.”

And, there’s strong public support to build new reactors next to existing ones. Although most Americans oppose building new nuclear reactors, 76% of those living within 10 miles of a nuclear reactor would welcome another one, according to the Nuclear Energy Institute. “Folks around the plant interact with men and women who work at the plants,” says Kerekas, explaining the support among plant neighbors.

The newest reactors, called Generation III, will look and operate much like the Generation IIs dotting the landscape today. A chain reaction in the fuel rods will heat water circulating through the core. Hot water piped to a steam generator then will spin a turbine that produces electricity. However, Generation IIIs will be bigger than their parents. Most plants will be 1000–1600 MW. Generation IIs typically are 1000 or smaller.

The biggest differences will be in the safety features. “When you have a very large plant, you can afford the overhead of additional safety equipment,” Meserve says. The cores of Generation III reactors, for example, will be surrounded by two 51-inch-thick concrete walls designed to withstand the impact of a commercial jet.

Passive emergency core-cooling systems will replace systems requiring electricity-powered pumps. “Emergency tanks might be high and work by gravity,” Meserve says. “Or they might be under pressure. When pressure in the primary system goes down, the secondary system would start up. [Electronically powered] active components can fail. With these systems, you’re relying on nature.”

The Cycle Solution

The highest hurdle on the road toward expanding nuclear power is the lack of a permanent site to store the waste. Radioactive material has been “temporarily” stored at nuclear plants for decades, while policymakers iron out objections to the proposed national repository at Yucca Mountain, NV.

Yet another, less obvious, obstacle to increasing nuclear power is the earth’s limited supply of uranium. “Some suggest we would run out in 200 years or so,” says Hans Gougar, manager of the advanced energy systems program at the Idaho National Laboratory.

That’s assuming tomorrow’s nukes run like today’s. Gougar and his colleagues know better. They’re working on the Energy Department’s Advanced Fuel Cycle Initiative to develop fuel cycles that would minimize the problems of supply and waste. The products of their efforts are expected to power Generation IV plants built within the next 25 years.

Traditional light-water reactors use fuel pellets or rods made of the abundant uranium-238 enriched with 3–5% of the more reactive and less plentiful uranium-235. It’s this reactive uranium that fuels the fission reaction. As the reaction continues, fission byproducts accumulate, eventually reaching a high enough concentration to have a significant negative impact on reactor efficiency. At this point, the highly radioactive “spent fuel” rods are removed and put into storage in concrete basins of water until it becomes cool enough to move into “dry” storage.

Tomorrow’s faster, breeder reactors would use fuel enriched with 20–50% uranium-235 and generate far less radioactive waste. “You start with a higher enrichment of uranium and because of the different materials in the reactor core, you get 10–100 times more uranium consumed,” Gougar says.

Although the fuel would contain more uranium-235, less of the element would be needed because it would be used so much more efficiently. “If we enrich the uranium and use the fast reactor cycle,” Gougar says, “we can extend the uranium supply much longer.”

Fast reactors would not only generate less waste but also expand the de facto capacity of waste repositories. The capacity of Yucca Mountain and other sites is limited by the heat that spent fuel generates. According to the Energy Department, Yucca Mountain could store 50 times more waste if it came from fast reactors. That would be enough storage to last at least through the end of this century.

Because the more highly enriched uranium burns much hotter, Generation IV reactors will require more-efficient cooling systems. An international team of designers have proposed several types of coolant, including fluoride salt and liquid sodium. Four of the six Generation IV models produce hydrogen, which someday might tackle another source of greenhouse gas—automobile exhaust. Forward-thinking nuclear researchers envision the hydrogen from nuclear plants being used to power cars cleanly.

“Our energy needs are increasing at the same time we’re becoming more concerned about the catastrophic climate effects,” Gougar says. “Fast reactors make sense.”

Trashing Nuclear Waste

If we all treated our trash in the same way that the nuclear-power industry does, thanks to the current political quagmire, our yards would look and smell like the city dump. The United States has yet to establish a permanent site for nuclear waste, forcing plants to stash their radioactive waste in spent-fuel pools and on-site dry casks.

“The absence of a permanent strategy is seen by the public as evidence of weakness in the overall strategy for managing the energy sources,” says Richard Lester, a nuclear-engineering professor at the Massachusetts Institute of Technology (MIT) and contributor to the 2003 report, The Future of Nuclear Power: An Interdisciplinary MIT Study.

The MIT group supports geological disposal such as the depository at Yucca Mountain, NV. But for years, the nuclear-waste depository designed for the site has been hopelessly tangled in red tape. The U.S. Department of Energy started studying the suitability of Yucca Mountain 20 years ago. Overwhelming opposition from residents and concerns about seismic activity around the site has slowed the site’s development. Eight years after the depository was slated to open, the Energy Department says that it won’t accept radioactive waste before 2017.

Policymakers originally planned for Yucca to hold 70,000 metric tons (t) of waste. With 56,000 t already in temporary storage at nuclear plants, the Bush Administration is now asking that the repository take up to 120,000 t.

Add the waste from a new generation of nuclear plants to the existing garbage pile, and Yucca Mountain will be full only a short time after opening—unless the United States adopts more efficient breeder reactors, or reprocesses its used fuel. Reprocessing would reduce radioactive waste by 95%. France, Russia, the United Kingdom, and Japan have recycled their radioactive waste for years. But the U.S. government in the 1970s abandoned reprocessing in an effort to prevent weapons-grade plutonium from getting into the wrong hands.

Until reprocessing can be made more secure, the MIT group endorses the ban. “I think we have a long way to go before [fuel reprocessing] should happen,” Lester says. “For economic, environmental, and proliferation concerns, we argue that we should continue with the once-through fuel-cycle approach.”

The Bush Administration, though, seems to be moving toward reprocessing. Early in 2006, President Bush introduced the Global Nuclear Energy Partnership, a plan that would promote reprocessing among the United States and allied nuclear powers. The partnership evokes Eisenhower’s Atoms for Peace plan. Allies that have nuclear weapons would share their nuclear-power technology with other countries. The allies also would supply uranium to countries that aren’t members of the nuclear-weapons club and take back their radioactive waste. Because both enrichment and reprocessing produce materials that could be used in weapons, the partnership aims to minimize the risk of nuclear-weapons proliferation by limiting uranium enrichment and reprocessing to the allies.

Energy Department researcher Harold McFarlane sees promise in recycling. “Even if we increased the use of nuclear energy by a factor of 10,” he says, “we’d still need only one repository.”

But to MIT’s Lester, reprocessing isn’t worth the proliferation risk. He and his colleagues recommend sending all radioactive waste into storage. “The administration advocates a policy that would preclude most other countries from reprocessing,” Lester says. “Is this a sustainable position for the U.S. to take?”

One day, he believes, radioactive fuel can be recycled in a way that won’t generate materials suitable for weapons. “My hope is that we will neither put all our eggs in the Yucca Mountain basket or recycling,” he says. “We need serious programs that look at ways to improve our waste-disposal techniques.”

Cynthia Washam, once an ardent opponent of nuclear power, is a freelance science writer who lives just a few miles from the St. Lucie nuclear-power plant in Florida. She writes the CareerView column for Chemistry.