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It’s Always Too Soon for Nuclear
Power—and Already Too Lateby Stan Cox
Having positioned itself in recent years for a comeback, the nuclear power industry is now, once again, on the defensive. Its promoters are arguing that nothing has changed, because this year’s nuclear disaster in Japan occurred under exceptional circumstances (as if the only catastrophes that can strike us are ones we anticipate). While the disaster in Japan has done much to strengthen anti-nuclear movements, it is important not to forget the many pre-Fukushima reasons why nuclear power has always been a bad idea.
With painfully little time in which to turn the tide on ecological ruin, both the conservation measures and the energy technologies on which we place our bets now had better be the right ones. If they aren’t, we will not have time to change our minds and go to Plan B later. If greenhouse gases are to be controlled, we will need not only to expand renewable energy but also to make very deep cuts in electricity consumption.
Political and economic decision-makers don’t like forcing choices like that, so it’s usually at this point in the discussion that the biggest deus ex machina of all, nuclear energy, is rolled out. Public support for a “nuclear renaissance” is being pumped up by the erroneous impression that nuclear plants produce electricity with few or no carbon emissions. Policy makers and even some environmental organizations and environmentalists who should know better have been only too happy to step to the front of the chorus.
To cover projected growth in world energy demand up to 2050 with nuclear energy would take another 18,500 plants…
Nuclear plants currently account for about 10% of the nation’s electric generating capacity and satisfy about 20% of total consumption (because they run closer to capacity a greater portion of the time than do other types of power plants). If we are to rely on nukes to replace coal and other fossil fuels in satisfying demand for electricity, we’ll need to start building new plants again, and fast. Look at the nation’s peak electricity demand in summer, which exceeds the winter peak by 144 billion kW.
To cover that additional peak demand—most of which can be chalked up to air-conditioning and refrigeration—would require the collective capacity of all 103 existing nuclear reactors in the United States, plus the construction of 43 additional average-size reactors. That would leave no nuclear-generated peak power for anything else, and to cover increased cooling demand additional plants would have to come on line every year.
Atomic cannibalism
In 2008, Joshua Pearce, assistant professor of mechanical and materials engineering at Queen’s University, published figures showing that if we were to cut world greenhouse emissions by 60% in an effort just to “stall” global warming, and if all non-fossil-fuel energy were to be supplied by nuclear plants, the number of nuclear plants worldwide would have to increase from the current 350 or so to almost 8,000. To cover projected growth in world energy demand up to 2050 with nuclear energy would take another 18,500 plants; in total, then, we would be putting into service 1.8 nuclear plants per day over a 40-year period.
Nuclear generation is “carbon-free” only if you ignore the resources consumed in constructing reactor plants, mining and refining uranium and other minerals, transporting materials, handling wastes, and decommissioning the plant. Taking all of that into account, nuclear plants still do have far lower greenhouse potential over their lifetimes than do coal- or gas-fired power plants. But the enormous amounts of energy that must be spent in advance to create the capacity required to generate nuclear energy in the future would require us first to go into deficit carbon spending for years.
…to generate nuclear energy in the future would require us first to go into deficit carbon spending for years.
Pearce examined the energy and emissions costs that would be incurred with a rapid buildup in America’s nuclear capacity, taking into account the entire lifecycle of nuclear plants and using the most complete data available on the energy requirements of each phase of that cycle, and concluded that with a high nuclear-industry growth rate, carbon savings provided by newly built plants will be “cannibalized” by the heavy carbon costs of building more plants each year and dealing with ever-mounting wastes. Therefore, during the very period between now and 2050 when deep cuts are needed to prevent runaway warming, we would be nullifying all of our progress. In the all-nuclear scenario, all emissions reductions achieved up to 2050 would be canceled out by growing emissions from plant construction, supply, and operation. [1]
Peak uranium?
What if the global economy were able to multiply the number of nuclear plants in service by 20- or 50-fold as required? Would there be enough uranium in the world to fuel them? Pearce describes the huge quantities of energy required to obtain fissionable uranium isotopes out of uranium ore, which contains only a fraction of a percent to a few percent uranium oxide (U3O8). Furthermore, it is unclear how much of the planet’s useful uranium ore, and how much of the radioactive isotope 235U, remain to be mined. Without further growth, currently known reserves would keep the global nuclear industry running easily beyond 2050.
But with strong growth, says the International Atomic Energy Agency, nuclear generation could exhaust today’s known, affordable uranium reserves well before 2050, with deficits arising as early as 2026. “Very high-cost” reserves and “unconventional” reserves—both costly in energy as well as money terms—would be needed to keep the industry growing. New, high-quality uranium deposits surely remain to be discovered, but it has been more than 20 years since “world class” deposits containing large quantities of high-quality ore have been discovered. As might be expected, the bigger the deposit, the lower the quality, on average; any significant new deposits will probably lie deeper underground than current ones and be more expensive to mine.
…it has been more than 20 years since “world class” deposits containing large quantities of high-quality ore have been discovered.
“Breeder reactors,” which produce new fissionable material faster than they consume the material they’re fed, have long been proposed as a source of abundant fuel, but the processes required to produce fuel for and run them are extremely dirty, dangerous, and expensive. Pearce told me, “Breeder reactors have a long list of contamination problems. To make a dent in climate change, it would have to be done on a really big scale. I’m not sure anyone would be organizing for that on a large scale. That would be crazy.”
He sees a need to spend our carbon wisely now, to build an infrastructure that can save carbon later: “Solar energy grew at close to a 50% rate last year; that made it a net carbon emitter for the year! No problem; we can overshoot a little. That’s OK.” But, he says, we can’t hit that atmospheric concentration that represents a point of no return: “We have to get all this stuff on line before we reach that threshold.” Solar, wind, geothermal, waste heat—all, he says, have more potential to reduce emissions in the near future than does nuclear energy. But no combination of energy sources can sustainably support current consumption levels.
Nuclear wastes: all questions, no answers
The hottest issue in the nuclear industry continues to be the handling of its waste products. The question of a permanent home for 62,000 metric tons of used nuclear fuel rods now stored in flimsy buildings alongside the reactors from which they came has so far stumped America’s scientific and political leaders. Bombmaking, power generation, and other uses of radioactive elements leave behind a wide variety of unneeded, hazardous isotopes. One of them, cesium-137 (137-Cs), is what makes used fuel rods fresh out of the reactor extremely “hot” (in both the thermal and the radioactive sense) and dangerous.
Today in America, fuel rods are almost always stored on site as they come out of the reactor, in nearby pools of water; a typical pool holds 400 tons of such rods, five times the tonnage in the reactor core itself, with twice as much 137-Cs per ton of rod. A study led by Robert Alvarez of the Institute for Policy Studies estimated that a fire resulting from an accident (such as the dropping of a cask of fuel that cracks the floor, draining the pool) or from sabotage could spread radioactivity over an area of 1,200 to 16,000 square miles. The National Research Council projected in 1997 that such an incident could result in 54,000 to 143,000 extra cancer deaths, 0.5 to 1.5 million acres of agricultural land condemned, and evacuation costs of $117 to $566 billion. [2]
Such a disaster was narrowly averted at the Fukushima Daiichi power plant in Japan, in March–April, 2011. There was leakage of water from the used fuel pool next to reactor number four, which caused a serious radiation leak; however, plant workers managed to dump enough seawater onto the pool to prevent a fire of the kind described by Alvarez and colleagues. The Fukushima workers had the good fortune of being a stone’s throw from the world’s largest body of water.
But what if calamity were to strike where water is limited? Head into the desert west of Phoenix, follow the biggest strands of power lines upstream, and you’ll find the 3,875-megawatt Palo Verde nuclear generating plant, the country’s largest. The plant generates huge quantities of heat; the 15,000 gallons of water per minute required to cool the plant’s radioactive cores come from treated municipal effluents. More than 20 years’ worth of used nuclear fuel, along with other, less dangerous wastes, have accumulated on the heavily secured six square miles of desert around the plant. Much of the used fuel sits in deep pools of water. Were the reactor cores and/or storage pools to undergo the kind of spectacular failure that devastated Fukushima—caused, as always, by some event that “never could have been predicted”—the volume of water required to keep the situation from spinning even farther out of control would not be available.
The US national target is containment of nuclear wastes for 210,000 years. [3] That won’t be easy; in just one-twentieth as many years, humans went from the hunter-gatherer life to the nuclear age. The most problematic element is plutonium, with stable isotopes ranging in half-life from 88 years to 88 million years. High-level radioactive wastes in Europe are commonly vitrified before storage. The process, which produces safer-to-handle, glassy hunks of still highly radioactive material, is finding support in the United States. But vitrified wastes, like all reactor wastes, generate lots of heat and have to be kept in an air-cooled containment area for as long as 40 to 50 years before they have lost enough heat that they can be buried, still emitting radiation, deep in the earth. And vitrification won’t work with plutonium; the element has to be removed from wastes that are to be vitrified. Until recently, it was hoped that a ceramic material called zircon (a compound containing zirconium, silicon, and oxygen) could be laced with 10% plutonium and remain stable for tens of thousands of years. But recent research found that radiation from the plutonium would degrade zircon’s structure in only 1,400 years, with the plutonium still almost as radioactive as when it was first stored. [4]
… how can a “Keep Out!” warning be communicated down through the millennia?
Vexing problems continue to multiply in the world of nuclear energy, yet for every problem, proponents offer a seemingly miraculous solution. One of the most seductive approaches to dealing with radioactive wastes is reprocessing, which is designed to increase fuel supplies and attack the waste problem simultaneously. By chemically teasing apart the elements in used fuel, it is possible to recover uranium and plutonium that can be used as fuel in conventional or breeder reactors, while leaving wastes that are easier to handle than was the original used fuel.
Or that’s how it’s supposed to work. France has long had reprocessing facilities capable of handling 1,600 tons of used fuel annually. But more than 30,000 tons of potentially usable reprocessed uranium fuel has piled up in storage. Meanwhile, France has accumulated an estimated 630,000 cubic meters of radioactive wastes sitting at two sites, leaking radioactivity, with little prospect of finding a new home anytime soon. [5]
In producing huge inventories of plutonium and other radioactive wastes, we have taken on a (literally) heavy responsibility, with no plan for how to deal with it in either the near or the distant future. Now respected people are insisting that we enter a new crash program to expand nuclear power, multiplying the burden of such wastes manyfold. And if we build 21st-century society around nuclear power, there’s no backing out. We will be committing the human species, probably for the remainder of its run here on Earth, to the care and feeding of a complex, high-maintenance infrastructure that cannot fail if we are to keep the ecosphere safe from radioactive wastes.
Durable physical barriers are only one part of the problem. Even if they work, how can a “Keep Out!” warning be communicated down through the millennia, into the mists of a distant future when, if our species is still around, it is likely no one will use any language, script, or medium known today? And how to ensure that whatever message we use will repel and not attract the curious? Scientists, artists, linguists, and various other breeds of thinkers have been pondering that problem for years, coming up with little beyond ideas like using bright colors and jagged graphics.
When it gets too hot for nuclear power
Meanwhile, back here in this lifetime, natural forces will continue to offer reminders of how fragile our own efforts at climate control are. During a 2006 European heat wave, the government of France, a nation that gets 80% of its electricity from nuclear plants, announced that “to guarantee the provision of electricity for the country,” reactors would be allowed to discharge waste water at higher temperatures than are normally allowed under environmental laws. That alarmed environmentalists, who pointed to a government finding that when heated water was drained from the reactors three years earlier, “hot water temperatures might have led to high concentrations of ammoniac [ammonium chloride], which is potentially toxic for the rivers’ fauna.” Antinuclear activist Stephane Lhomme told reporters, “Global warming is showing the limits of nuclear power plants.” [6]
Water from Lake Michigan normally used to cool the reactor cores had itself become overheated…
On the last day of July 2006, American Electric Power Co. shut down one of two nuclear reactors in Bridgman, Michigan, that supply electricity to Chicago and other areas. Water from Lake Michigan normally used to cool the reactor cores had itself become overheated by the summer’s blazing temperatures, and inside the containment building, it was 120 degF. [7] The following summer, the Tennessee Valley Authority shut down the Browns Ferry reactor in northern Alabama when its water supply from the Tennessee River reached 90 degF, an ineffective temperature for cooling the core. A utility spokesperson said, “It’s the hottest in 20 years. We don’t believe we’ve ever shut down a nuclear unit because of river temperature.” [8]
Both incidents were especially untimely, occurring at times of peak power usage by air-conditioning; record temperatures first pushed air-conditioning demand and electricity usage to the limit and then shut them off. Future warming of the atmosphere by greenhouse gases is expected also to raise the temperatures of rivers and other water bodies that supply cooling water for nuclear energy [9], so the frequency of plant shutdowns during times of peak air-conditioning demand could rise in coming years. Finally, as Alyson Kenward notes, coastal nuclear plants are further threatened by the rise in sea levels that is expected with continued climate disruption.
It is far too early to start expanding nuclear-power capacity, and because of the many intractable dangers, it always will be too early. Meanwhile, in view of the massive up-front carbon emissions required to build large numbers of nuclear plants, it’s already too late as well.
Stan Cox is a senior scientist at The Land Institute in Salina, Kansas. This article is adapted from pages 164–169 of Cox's book Losing Our Cool: Uncomfortable Truths About Our Air-Conditioned World.
Notes
1. Joshua Pearce, Thermodynamic Limitations to Nuclear Energy Deployment as a Greenhouse Gas Mitigation Technology, International Journal of Nuclear Governance, Economy and Ecology 2 (2008), 113-30.
2. Robert Alvarez et al., Reducing the Hazards from Stored Spent Power-Reactor Fuel in the United States, Science and Global Security 11 (2003), 1–51.
3. Valerie Brown, Nuclear Waste: With Plutonium, Even Ceramics May Slump, Science 315, 5809 (2007)
4. Ian Farnan, Herman Cho and William Weber, Quantification of Actinide -Radiation Damage in Minerals and Ceramics, Nature 445 (2007), 190-93.
5. Solveig Torvik, The French Fix, Seattle Post-Intelligencer, April 22, 1998; Shaun Burnie, French Nuclear Reprocessing—Failure at Home, Coup D’etat in the United States, Public Citizen, May 2007, http://www.citizen.org/cmep/energy_enviro_nuclear/nuclear_power_plants.
6. Julio Godoy, European Heat Wave Shows Limits of Nuclear Energy, CommonDreams.org, July 28, 2006, http://www.commondreams.org/headlines06/0728-06.htm.
7. Shannon Harrington, U.S. Heat Wave Heads to Northeast, May Break Records, Bloomberg News, July 31, 2006.
8. Beth Rucker, Heat Wave Kills 41 in South, Midwest, Associated Press, August 17, 2007.
9. This effect has been seen in rivers and lakes in Europe. See R. E. Hari, D. M. Livingstone, R. Siber, P. Burkhardt-Holm, and H. Güttinger, Consequences of climatic change for water temperature and brown trout populations in Alpine rivers and streams,” Global Change Biology 12 (2006), 10–26; D. M. Livingstone, Impact of secular climate change on the thermal structure of a large temperate central European lake, Climatic Change 57 (2003), 205–225.
[12 dec 11]