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We’ve all been watching the agony of the Japanese as they struggle to control the nuclear power stations damaged by the earthquake and tsunami. What concerns everyone, I think, is that Japan is one of two countries, along with France, that have made nuclear power really work.1 And now, it seems, even they have trouble with the resource.
Nuclear power has a bad reputation in the United States. During the 1950s, the Atomic Energy Commission and its technology supporters, seeking peaceful uses for fission, urged utilities to build nuclear power plants on the basis that the electricity would be “too cheap to meter.” Free power from rocks—what could be better? Many utilities took up the cause and built one or more nuclear plants. But the energy turned out to be anything but cheap.
For one thing, the regulatory burden on a nuclear plant is much greater than on any other energy resource. When I worked at the engineering company, we had several nuclear projects under way. Every step of design and construction is monitored, documented, and filed for future reference. To take just one example, the steel for rebar in the concrete of the containment is tracked from the steel mill to the construction site using a chain of custody—lot numbers, way bills, dates in and out of storage, final placement in the structure, with signatures all the way—very much like the provenance that follows a piece of evidence from crime scene to trial.
When I worked at the public utility, I met the sort of people who operate, maintain, and refuel a nuclear plant. These are serious, clear-eyed, methodical people. Think of a conscientious peace officer or medical technician—the sort of people you trust. The plant’s safe and efficient operating record is a major point of pride with them. They take their processes and procedures seriously. They never talk or joke about cutting corners. To get a feel for the life inside a nuclear plant, it’s as clean and orderly as a hospital, and there are signs everywhere identifying who has access to which rooms, under what conditions, with what equipment—and every sign carries the signature authorization of the plant manager or area supervisor. No one is in doubt about what he or she is supposed to do in any situation.
The 70 or so nuclear plants in the U.S. have been run successfully and mostly without incident. Today they provide more power than ever before. Improved practice has boosted their capacity—that is, the amount of time the plant actually generates electricity, as opposed to being shut down for maintenance and refueling—from about 56% in the 1980s to more than 90% currently. A safe operating record and high utilization are good things.2
But still … there is the potential for catastrophe when handling highly radioactive material. We experienced loss-of-coolant accidents at Three Mile Island in 1979 through operator error and now in Japan through a natural disaster. Although there was no release of radiation beyond the plant boundaries at Three Mile Island, and it’s unclear what releases there have been or will be in Japan, the potential for harm is there. If containment is breached, there can be widespread environmental damage and human illness, as at Chernobyl. However, it should be pointed out that the Chernobyl reactor was a completely different design, moderated by graphic blocks instead of boiling water, from the reactors in the U.S., Japan, or France. And the Chernobyl accident was attributed to a risky operating procedure that the state commissars wanted to try and the plant engineers argued against. And yet, experiencing only three notable incidents in 60-odd years of reactor operation is a pretty good record.
There was a time when the low energy ratio of nuclear power was its biggest commercial drawback. That is the ratio of energy output from the plant divided by the energy input. In the case of nuclear fuel, that input is determined by the costs of mining the uranium ore, transporting it, refining it, concentrating the fissionable U-235, making the fuel pellets, and assembling the fuel rods. With an average plant capacity factor of 56%, you don’t get enough power out of the plant to make up for the energy—usually in the form of fossil fuels—that you burned to make the fuel. The good news is that, with improved enrichment technologies that lower the cost of fuel and those higher capacity factors that spread the cost over more energy production, the energy ratio is more favorable these days.3
Still, the standard wisdom has been that nuclear energy isn’t actually profitable without completing the nuclear fuel cycle. The final steps in the cycle, which starts with mining the ore and continues through running the reactor, address reprocessing the spent fuel rods to recover the fractions of unburned U-235 and newly created plutonium for making new rods, and then disposing of the radioactive wastes. The United States halted reprocessing of nuclear fuel after an Executive Order by President Carter because he did not want to create a “plutonium economy” that might support nuclear terrorism.
Still, we have do to something with the spent fuel rods. Because we’ve also abandoned work on long-term storage at repositories like salt mines and granite caverns in the deserts of the U.S. west, American plants are now holding their spent fuel in “swimming pools”—which cool and shield the rods with filtered water—at the plant site. And those temporary storage measures are rapidly filling up. There will come a day, sometime in the next ten years, when many existing plants must shut down because they can no longer store additional rods. And there will come a day, sometime in the next 40,000 years, when humanity will have to close down the swimming pools and deal with the decaying rods.
Early on, France undertook the nuclear option in wholehearted fashion. With a single nationwide utility, the French concentrated on a single reactor design, so that everyone in the system would be familiar with its operation and maintenance. They run teams of experts who do nothing but go around the country sequentially refueling plants. And because the shutdown for refueling is also the time when every part of the plant undergoes extensive evaluation, maintenance, and rebuilding as necessary, this team is charged with overall plant health. In contrast, in the United States, each utility builds its own plants as engineering one-offs, choosing from among two different reactor designs and many options for steam supply, turbine, and control systems.4 Each U.S. utility does its own refueling and long-term maintenance, although under supervision of the Nuclear Regulatory Commission, so they each must absorb the costs of the specialized engineering teams required to perform this work.
France reprocesses its fuel to get the extra boost from recovering unburned U-235 and reactor-bred plutonium. And they reprocess fuel from Japan under contract. Reprocessing includes appropriate disposal of low-level radioactive waste from the clay and cladding of the rod bundles, and vitrification and sequestration of the high-level wastes from burned uranium.5 So at least two countries in the world are already dealing with the long-term problem of spent fuel.
With the new fear of global warming from fossil fuel use, many people want to see more nuclear power plants built in the United States. However, the last contract for a new nuclear plant in this country was signed in the mid-1970s. That was before the disasters at Three Mile Island and Chernobyl, and not long after the first commercial power reactors had come on line in the late 1960s. Clearly, even then, the utility companies were coming to understand that nuclear power—far from being “too cheap to meter”—was too expensive to operate. The fact that the later plants were built at all was a matter of engineering pride, political inertia, and the economic desire to recover money already invested.
Before nuclear power can become viable again, we have to address three conditions: a new, inherently safe, stable, and simple reactor design; facilities for long-term storage of wastes; and ideally a facility for nuclear fuel reprocessing. Without these—plus a political climate that gives the nuclear option its irrevocable and unimpeachable blessing—the energy utilities in this country won’t touch new nuclear power.
1. In 1987, at an Energy Daily conference in Washington, DC, I heard the then-president of the French national electric utility, Electricité de France, describe the nuclear option as, “France has no coal. France has no oil. France has no choice.”
2. For an overall analysis of nuclear power in this country, see the U.S. Energy Information Administration.
3. For a detailed analysis of power systems and energy ratios, see the World Nuclear Association.
4. To give just one example of the complexity that exists in the U.S. nuclear power industry, when I worked at the engineering company a group of our engineers and technical writers was put under contract with the local utility, PG&E, to help them bring the Diablo Canyon nuclear plant on line. One of our system engineers walked into the room one day shaking his head. All of the control circuits in the plant operated at 38 volts, he said. I asked if that was a problem. No, he said, the controls would work fine, but 38 volts was a hydro power standard, not the standard voltage used in nuclear plants. PG&E’s design and engineering group got their start in the hydro business, and apparently when they turned to designing their nuclear plants, they used the standards they were familiar with. It doesn’t hurt the plant, but it sure confuses anyone coming in from the outside.
5. Briefly, low-level wastes are common materials that have become irradiated and now emit alpha and beta particles and gamma rays. These are all forms of ionizing radiation and therefore dangerous to humans. But irradiated materials don’t emit fast neutrons, which alone have the power to irradiate other materials in turn and make them radioactive. (Otherwise, the whole world would gradually start to glow.) Only naturally occurring fissionable isotopes like those of uranium and radium, and their decay products like isotopes of strontium and cesium, emit neutron radiation and so they are considered high-level waste.