Imagine your neighbourhood with a nuclear power plant a short drive away. You can see the tips of the cooling towers from your upstairs window. You know the plant is a source of clean, greenhouse-gas-free (or almost-free) energy production. It is a new, “inherently safe” designed plant, built with subsidies from the federal government, your taxpayer dollars. The waste from the plant is kept on site in a reinforced bunker — that and the armed-guard force protect it from sabotage. The waste will eventually go to a repository located within 800 kilometres of your home. In fact, most communities have similar nuclear power reactors; yours is not unique. They are helping to defer the deleterious effects of greenhouse gases on the climate. But are you comfortable with it there?
Worldwide electricity demand is expected to increase in the years to come, not only from familiar residential and industrial uses but also potentially from new demands such as the formation of hydrogen fuel. Given a business-as-usual scenario of the future, where the world’s population increases to about ten billion by 2100, electricity generation is expected to almost double by 2020, quadruple by 2060, and quintuple by 2100. In concert with the growing evidence of a link between fossil fuels and climate change, a decrease in reliance on fossil fuels for electricity supply is needed. Estimates suggest that by 2020, carbon emissions from electricity generation alone will contribute double that of the current rate. If these levels are not reduced, the associated climate warming may produce disastrous results. How can we meet the electricity needs of an evolving world but reduce carbon emissions? Nuclear power may provide the answer.
Currently, 16 percent of the world’s electricity is supplied by nuclear power. Certainly the current nuclear capacity reduces the atmospheric load of greenhouse gases that would otherwise be generated by coal-, oil-, or gas-burning plants. The question is, can nuclear step into the void and actually expand enough to take a bigger bite out of the carbon load?
First, it is important to understand where nuclear power is in relation to other sources of electricity. As of March 2003, there were 437 commercial nuclear power reactors in thirty-one countries, with a total of about 360 gigawatts capacity, enough to power 400 million California homes. In comparison, fossil fuel plants had a worldwide capacity of about 2,400 gigawatts at this time, enough for almost 3 billion California homes. Though the United States gets only 19 percent of its electricity from nuclear power, it still has the largest nuclear energy fleet in the world. As of 2003, the United States had 103 licensed operating reactors in thirty-one states.
Much has been made of the potential for expanding nuclear power, but this would only occur over the long term. Nuclear capacity has hardly grown in the last fifteen years and will not likely grow much over the next fifteen years. The United States, for instance, last ordered a new nuclear power plant in 1978, and no plant ordered after 1973 was built (in large part, this was due to the accident at Three Mile Island). Thirty-three new nuclear plants are being constructed in eleven countries, predominantly India, China, Ukraine, Russia, and Japan. Little expansion is occurring in Europe and none in the United States or Canada.
In the United States and some European countries such as France, the trend is to extend the lifetime of existing reactors. The U.S. Nuclear Regulatory Commission (NRC) has begun granting twenty-year licence extensions for power plants. Germany, Sweden, and Belgium, on the other hand, have voted to phase out nuclear power before all plants have completed their licensed lifetimes. Furthermore, Austria, Denmark, Greece, Ireland, Italy, and Norway have prohibited the use of nuclear power. At the same time, many nuclear power plants in the United States and Europe have had power uprates, which have allowed the plants to increase their electricity-generating capacity. These power uprates enable the plants to produce electricity more competitively.
Deregulation of energy markets in the United States and elsewhere has allowed the restructuring of electric utility companies. For nuclear power, that has meant consolidation. In the U.S., for example, in 1991, 101 utility companies owned 110 reactors, but by 1999, the number of owners had decreased to 87, of which 12 owned more than 50 percent of the total generating capacity. Restructuring of nuclear utilities allowed larger companies to take advantage of economies of scale in maintaining and operating their plants. Previously, a company that owned a single nuclear power station may have decided to shut down instead of investing to replace aged, expensive equipment, whereas larger power plant owners can absorb these costs more easily.
The short-term future of nuclear power in countries like the United States looks somewhat brighter than it has in years. The regulatory climate is more favourable than before, and existing plants are more economical and therefore more competitive with fossil fuels, because the capital costs of building the nuclear power plants have been paid or the costs shifted to ratepayers. Finally, there are new reactor designs on the horizon.
But the future is not clear. Currently, all major expansion is occurring in developing countries, and even that is limited. Nuclear power is stagnating or shrinking in most developed countries. But nuclear power is the only currently existing, large-scale, geographically unlimited source of greenhouse-gas-free (or at least reduced) electricity. And for those countries that do not have cheap access to fossil fuel resources, nuclear power may be one of the only sure sources of reliable electricity. What would it take to expand nuclear power on a large scale, and what scale of expansion would reduce climate-change effects?
Nuclear power will not be the only answer to our energy needs in the future. First, nuclear power can only reduce greenhouse gas emissions from electricity production — not from fossil fuel use in transportation, for example. Second, the claim that nuclear power produces no greenhouse gas emissions is not actually correct. Greenhouse gases are emitted during the extraction of uranium for fuel, as well as during uranium processing and enrichment. Greenhouse gases are also emitted in the production of construction materials for nuclear power plants, such as concrete and steel. In addition, there are some minor emissions of greenhouse gases during reactor operations by secondary generators that are required in case of accidents. These generators must be tested on a regular basis, and during the testing they emit carbon dioxide and other gases.
Most nuclear power reactors in operation in the world today — those termed light water reactors — require uranium to be enriched in one of its naturally occurring isotopes, uranium-235, for use in fuel. The enrichment process can be very energy intensive, depending on the exact method used. The most energy-intensive enrichment process is gaseous diffusion, where uranium hexafluoride gas is passed through membranes that retard the movement of the heavier uranium-238 isotope. These plants tend to be huge as well as energy intensive. The Paducah, Kentucky, gaseous diffusion plant gets most of its electricity from coal-burning power plants. Thus, its annual operation creates the emission of about as much greenhouse gases as that from three 1,100-megawatt coal plants.
Other enrichment technologies, such as centrifuge plants, are less energy intensive than gaseous diffusion; nonetheless, they still use electricity. Unless a system can be made in which all the electricity used in uranium mining, milling, and enrichment comes form nuclear power itself, nuclear-produced electricity will result in the emission of some greenhouse gases.
The larger question that we are trying to address is, what is a reasonable expectation for greenhouse-gas-emission reductions from nuclear power? Today’s nuclear power plants save 600 million tonnes of carbon per year from going into the atmosphere from equivalent power-producing coal-fired plants. But this is just 10 percent of the total amount of carbon released into the atmosphere each year. Nuclear power saves even less, about 250 million tonnes of carbon per year, for gas-fired power plants. For nuclear power to make a substantial dent in carbon emissions, it would have to reduce emissions by at least a third. By 2100, given that electricity usage may have increased five-fold, nuclear power would have to increase its share of production from one-sixth (what it is today) to one-third multiplied by five, or about ten times.
What does a ten-fold increase in nuclear power generation translate into?
This would entail building in the order of 3,200 new mid-sized nuclear plants worldwide, 900 of them in the United States alone. The implications of such an expansion are impressive in terms of the waste and nuclear weapons materials produced. If these 3,200 new plants were of the same variety as those that now exist in the United States, namely, light water reactors, then the amount of used nuclear fuel produced on an annual basis would be 72,000 tonnes. That amount is equivalent to that planned to fill the entire U.S. repository at Yucca Mountain, Nevada. One percent of that fuel, 720,000 kg, would be plutonium, of which only 4 kg is needed to make a nuclear weapon.
What does this mean overall? First, it is important to note that I am only considering long-term scenarios here, where the tenfold increase takes place between 2050 and 2100. It would not be possible to increase capacity so greatly over the short term, within the next ten or twenty years. It would simply take too long to build all the nuclear plants and supply all the equipment and personnel.
Over the long run, however, it would be possible to complete such an expansion. In doing so, a number of significant issues would require resolution before the world turned to nuclear power as a (partial) solution to greenhouse gas emissions. These include the cost of building new power plants, safety issues posed by the existence of over 3,000 plants, huge volumes of nuclear wastes, nuclear weapons proliferation, and the potential for terrorist strikes on nuclear power plants. Other issues include public acceptance of nuclear power and the low-level doses of radiation it imparts, and infrastructure issues, especially those of an aging workforce with few replacements and a decreased manufacturing capability.
Whether nuclear power is an attractive alternative to governments and investors depends partly on the comparative costs per kilowatt-hour of electricity generated. In some countries, nuclear power is currently competitive or even cheaper than fossil fuel alternatives. This is true for countries like Japan, France, Finland, and Canada, which have few fossil fuel resources. In all countries, nuclear power is characterized by high initial capital investments in comparison to coal- and gas-fired power plants. Note that although the current per-kilowatt-hour cost of nuclear-produced electricity in France, Japan, and Canada is low, these countries are not adding new nuclear plants at the moment. That may be largely due to the high cost of capital investment needed to build a nuclear plant.
Initial capital costs for nuclear power plants tend to run about 60–70 percent of per-kilowatt-hour electricity generating costs. In contrast, nuclear power has relatively low production costs, which include fuel, operations, and maintenance. The average cost to build a new nuclear reactor in the United States is estimated to be between US$1.5 billion and US$3 billion. In comparison, the cost of building an equivalent-size natural gas power plant is around US$450 million. In the past, nuclear electricity sales have not recovered capital costs, and in the United States these costs have consistently been underestimated by about three times the original estimate.
Another variable in nuclear power economics is construction time. For a country like the United States where no nuclear power plants have been built for decades, the construction time is a great unknown. It could take as little as five years or longer than ten years. It is difficult for an investor to commit to such uncertainty on the return on investment. Construction times tend to be much longer than for an equivalent natural gas plant. In deregulated energy markets, projects with long construction times are possible only with favourable interest rates and payback periods.
In addition to the capital and production costs, there are external costs such as those for managing and disposing of nuclear waste. The U.S. Nuclear Waste Policy Act required utility companies to charge ratepayers US0.1¢ per kilowatt-hour for a Nuclear Waste Fund, which would cover the costs of disposing of spent fuel in a geologic repository. From 1983 to 2002, U.S. ratepayers paid over US$16 billion into the Nuclear Waste Fund, but only US$8 billion has been spent on the characterization of Yucca Mountain in Nevada, because the U.S. Congress has used the rest to defer budget deficits.
Other external costs are those for decommissioning nuclear power plants and those to cover insurance funds in case of catastrophic accident. Decommissioning costs may, in fact, be underestimated. In the United States, two studies showed that estimates of decommissioning costs had risen from about US$300 million per reactor to US$500 million per reactor in one year. Because evidence suggests that these costs may continue to rise, and because no light water reactor has been completely decommissioned (including spent-fuel removal), there is reason to believe that utility companies may not be collecting enough money to cover these costs in the future.
An additional source of economic uncertainty with nuclear power is the potential for high external costs from plant aging. As a plant ages, large and expensive pieces of equipment may need to be replaced. Moreover, even if the plant owner sees no need for part replacement, the regulators may require it. An example is the experiences of the Davis-Besse plant in the United States. It was a surprise to both the plant owners and the NRC that holes developed in the reactor head, which, if they had gone completely through the head, would have resulted in a large accident. The reactor owner has been trying to fix the problem, but the reactor has been off-line for over a year now and the NRC has yet to allow it to resume operations.
A ten-fold expansion in nuclear power would occur only if initial capital costs were somehow controlled. This could be done via investment guarantees and government subsidies, as some in the U.S. Senate are trying to provide. To be successful, nuclear power has to compete with other energy sources, and some renewable technologies may be less costly and more competitive in the future than they are now.
Nuclear reactors harness the energy produced by the splitting of atoms (fission), usually uranium, though sometimes plutonium. In doing so, a reactor requires two processes: moderation of the energy of the neutrons that split the atoms to the energy needed to maximize fission, and cooling of the reactor components — to safely run the reactor. The coolant also performs the important job of transferring heat energy produced by the reactor to the turbines that produce electricity.
Reactors are generally distinguished by the types of fuel, moderator, and coolant that they use. In the United States, reactors were developed from those used in nuclear submarines. The most successful of these was the light water reactor, which used fuel slightly enriched in uranium-235. Light water reactors use regular water as both coolant and moderator. Two types of light water reactors are in use in the world today: pressurized water reactors, in which the core of the reactor and its water are kept under high pressure so that the water does not boil, and boiling water reactors, in which the water is allowed to boil, generating steam to run the turbines.
Britain and Canada decided to base their initial reactor designs on uranium fuel that didn’t require enrichment. Britain developed gas-cooled reactors, which used carbon dioxide gas as a coolant and graphite as a moderator. These are known as Magnox reactors after the magnesium-rich alloy used to clad the uranium metal fuel. Later models of Britain’s gas-cooled reactors used slightly enriched uranium dioxide fuel. Canada developed the CANDU (short for CANadian Deuterium Uranium) reactor, which uses natural uranium as a fuel and heavy (deuterium-based instead of hydrogen-based) water as both coolant and moderator.
Two other reactor designs merit mention. The Soviets designed a light water–cooled, graphite-moderated reactor known as the RMBK, the most infamous example of which is the Chernobyl reactor. Many of these reactor types are still in operation in Russia and Eastern Europe. The other important design is the liquid-metal fast-breeder reactor. This reactor uses fast neutrons and does not need to slow them down with a moderator. The coolant used is either sodium or lead-bismuth. Although a number of countries had fast-breeder reactor programs, many of them shut down due to cost and technical difficulties. Only three of these reactor types are in operation in the world now.
For those who remember them, the experiences of living through the Chernobyl and Three Mile Island nuclear power plant accidents were nail-biting moments. The 1979 Three Mile Island plant accident did not result in large releases of radiation, but the seeds of uncertainty planted in the public’s mind spelled the end of expansion for the nuclear industry in the United States. The 1986 Chernobyl accident, unfortunately, was a different story; it resulted in forty-two immediate deaths (from exposed workers) and has caused a twenty-five-fold increase in childhood thyroid cancers in nearby Belarus. It will also likely result in an additional 6,500 cancer deaths in nearby residents and “liquidators” who worked to contain the radiation. A third reactor accident — involving a nuclear-weapons-production reactor, not a civilian power reactor — at the Windscale plant in Sellafield, England, in 1957 released radioactivity in amounts between that of Three Mile Island and Chernobyl.
The problem with safety issues for nuclear power is the public’s well-founded fear of radiation — which can injure or kill but cannot be sensed — based on the destruction wrought by the United States’ use of nuclear weapons in Japan at the end of World War II. Nonetheless, many years have passed since the nuclear industry experienced an accident. The emphasis now is on safety issues from aging nuclear power plants and the enhanced safety of new plant designs.
The existing fleet of nuclear power plants is aging fast. For example, the average age of the world’s operational nuclear power reactors is twenty-one years. As mentioned earlier, the United States is already beginning to extend the licensed lifetimes of nuclear power plants from forty years to sixty years. One example of an aging problem that could affect safety is the corroded lid on the reactor at the Davis-Besse plant.
A tenfold increase in the number of reactors would greatly increase the potential for safety issues. It would certainly over-burden existing regulatory agencies, which would have to adjust accordingly, including increases in government appropriations. With so many reactors, would all equipment, operators, and regulators be of top quality?
There are a number of new reactor designs that claim to be safer to operate than the more ubiquitous light water reactor designs of the 1970s. Some of these new reactor designs have not fallen far from the original “tree” and are based on the light water reactor workhorse in use in the United States and much of Europe and Asia. One advantage of these systems is that there will be a standardized plan for the reactors. U.S. nuclear reactors have unique designs, which has not allowed the U.S. nuclear industry to take advantage of economies of scale. The new design will be simpler and the plants will have a longer life, about sixty years. The simpler design will reduce the probability of a reactor accident. Finally, the reactors will be designed to burn fuel longer, to reduce waste volumes. These designs are mostly for large-scale plants, but some are mid-size (600-megawatt) designs.
Nuclear engineers have not limited themselves to simply modifying existing reactor designs; some have designed advanced reactors. One is the high-temperature gas reactor (HTGR), the first of the new generation of which is planned for construction in South Africa. Though the design is not new, it takes advantage of a modular plan (so that additional modules can be added to a single site to increase capacity) and a more accident-resistant fuel. These reactors are expected to be much more efficient than existing nuclear power plants. The HTGR uses helium as a coolant and operates at high temperatures, about 950°C. The fuel is designed either as “pebbles” of uranium coated with carbon and silicon carbide or as uranium embedded in graphite and arranged in hexagonal prisms. The pebble type of fuel is planned for the South African reactor, thus it is termed the “Pebble Bed Reactor.”
Although HTGRs are described as “inherently safe” in design, they do have some potential safety issues. One is the fact that they are designed without containments — large, reinforced structures built around the reactor vessel itself. A containment is what the Chernobyl reactor lacked, and so when it melted down, there was no structure available to contain the radioactivity. High-temperature gas reactors can be designed without containments because the probability of a meltdown is very low, due to the fuel’s ability to slow the fission process (splitting of uranium atoms) as the temperature increases. On the other hand, the reactors are susceptible to fire if air or water comes into contact with the fuel, and these reactors produce more spent fuel than do comparable-size light water reactors.
The other advanced design under discussion also is not new, but entails numerous obstacles which relegate it to the far future, if it is to be used at all. This is the fast neutron reactor, which typically takes advantage of the fast neutrons emitted by plutonium and therefore requires plutonium fuel. The idea behind these reactors is that they not only produce electricity but also replace or breed their fuel through nuclear reactions with a uranium “blanket,” thus they are often referred to as fast-breeder reactors. For coolant these reactors require some type of liquid metal such as sodium or lead-bismuth; others require a gas. Current designs of these plants are exorbitantly expensive. In addition, the use of plutonium fuel can lead to diversion for and proliferation of nuclear weapons.
Nuclear waste remains an unresolved problem in all countries that use nuclear power for electricity production. Considering that 20 to 30 tonnes of used nuclear fuel are produced per gigawatt per year, the current capacity of the world’s nuclear power plants produces between 7,000 and 11,000 tonnes of spent fuel annually. In many countries, this spent fuel continues to reside at reactor facilities, awaiting final disposal. In some countries, such as France, the United Kingdom, Russia, Germany, and Japan, this fuel has been transported to reprocessing facilities, where its unused uranium and newly produced plutonium are extracted. Only one of these reprocessing countries so far has succeeded in using a large portion of the plutonium as fuel in existing reactors; the rest simply stockpile the separated plutonium.
The reprocessors are not off the hook in dealing with nuclear waste, however. They have reduced the overall volume of high-level waste, but they have vastly increased the volumes of low-level and intermediate-level wastes. And the high-level waste contains all the thermally and radioactively hot materials that the original spent fuel contained. When disposing of waste, the volume is not as important as the heat production.
The international consensus for solving the problem of high-level waste is to dispose of it in geologic repositories, whether in the form of spent fuel or vitrified high-level reprocessing waste. Most countries with nuclear power are developing a geologic repository, though the task has proved more difficult than previously thought. The United States, Finland, and Sweden have perhaps the most “advanced” waste disposal programs, though none have come close to actually opening a repository.
The issues facing successful disposal of nuclear waste fall into two main categories: political and technical. Though many in the nuclear industry claim that the nuclear waste problem is technically solvable, there are still many uncertainties attached to the science and engineering of nuclear waste disposal. First of all, it is one endeavour for which we will never know the results. If the waste leaks 1,000 years from now and affects humans living near the repository site, a result that is judged a failure by most repository regulations, we won’t know it.
Second and perhaps more important is the fact that disposal is using the barriers provided by the local geology in addition to the engineered ones of the waste canisters, the tunnel, backfill, and others. Because one of the main barriers to the release of radionuclides to the environment is the geology, predictions of geologic conditions and behaviours of radionuclides and engineered materials in the geologic system over geologic time periods are essential to ensuring a successful repository location. These predictions rely on geology, a retrodictive (explaining the past), not predictive, science. Therefore, geologic disposal of nuclear waste will entail some amount of uncertainty. And this is the link to the political issues.
It is not clear that, given the inherent uncertainty in ensuring safety when disposing of nuclear wastes, it will ever be politically feasible to open a repository. There are a number of models for attempting to do so, ranging from the democratic methods of France, Finland, and now Germany, where the public in the site location is given ultimate veto power over potential sites, to the more top-down approach favoured by the United States. U.S. site selection was essentially done by Congress in the Nuclear Waste Policy Act Amendments of 1987, in which it forewent the plan to characterize and select from three sites to one, the Yucca Mountain site in Nevada.
The problem for a future with a ten-fold increase in nuclear power production is the huge amounts of waste produced. To manage and dispose of an annual production of 70,000 to 110,000 tonnes of spent fuel will require a new way of dealing with the waste. For comparison, the Yucca Mountain site in the United States is currently designed to hold 70,000 tonnes of waste. The ten-fold increase would require tens to hundreds of Yucca Mountain–type sites. It’s not clear that this will be either technically or politically feasible.
The decision may be to wait for a better alternative to geologic repositories to come around. But this would mean that an industry is allowed to continue to produce highly toxic wastes without an implemented and proven plan to deal with them. One technology on the horizon is transmutation of nuclear waste, which allows the alteration of many long-lived radionuclides into shorter-lived ones. This technology will still require some type of geologic repository for the disposal of the shorter-lived radionuclides, though. It will also require the construction of new and expensive reactors or accelerators.
The hardest part of making a nuclear weapon is obtaining the nuclear materials to power it. Therefore, perhaps the most serious problem with a large expansion of nuclear power is the threat to international security from the proliferation of nuclear weapons. There has always been a direct connection between nuclear power and nuclear weapons because the materials used to power the weapons are the same as those used to power reactors, the fissile materials plutonium and highly enriched uranium. England obtained some of the plutonium for its nuclear weapons from power reactors. India got its first significant quantities of plutonium, used for a “peaceful nuclear explosion” in 1974, from a research reactor of Canadian power reactor design.
Our international system to detect the diversion of fissile material has already been challenged by Iraqi and North Korean diversions. How would the system handle ten times more reactors? Clearly, proliferation-resistant nuclear energy technologies are required.
One potential proliferation-resistant power reactor technology is the Radkowsky concept, which uses thorium instead of uranium fuel in existing light water reactors. The advantage here is that less plutonium is produced when the fuel is irradiated or “burned” in the reactor than in typical light water reactor designs. Thorium fuel is not a complete solution, though, as it produces the isotope uranium-233, which can be used to make nuclear weapons. The idea is to dilute this with uranium-238 to levels impossible to make usable nuclear explosions.
Another suggestion is to use high-temperature gas reactors. With this type of reactor, proliferation resistance is obtained through the high burnup (long fuel irradiation time) of the fuel, which creates plutonium isotopes that make the manufacture of nuclear weapons difficult. Of course, the reactor need not be operated in that manner. Furthermore, HTGRs use fuel that is more enriched in uranium-235 compared with that used in light water reactors. Thus, countries using HTGRs may need enrichment technologies. Once uranium is enriched to 20-percent uranium-235 (the level needed for many HTGR designs), it is relatively easy to enrich further to 90 percent, posing proliferation risk.
Finally, some have suggested fast-breeder reactor technologies in which plutonium is not separated from the fission products in the fuel. The fission products make the use of this material as a nuclear weapon impossible. Of course, a country with the right resources can still separate the plutonium from the fission products. Moreover, the use of breeder reactors creates more plutonium, increasing the diversion/theft problem.
Used nuclear fuel from light water reactors cannot be used in nuclear weapons, though the plutonium in it, which makes up about 1 percent of the mass of the fuel, can be. Perhaps the main problem with nuclear power is that some of the associated technologies — reprocessing of spent fuel to separate plutonium and uranium enrichment technologies — pose the highest proliferation threats. Separated plutonium can easily be fashioned into nuclear weapons by knowledgeable people. Highly enriched uranium is arguably even easier to make into nuclear weapons. Thus, for years the world has safeguarded these technologies in non–nuclear weapons states.
The problem with a ten-fold expansion in nuclear power is the resulting growth and spread of these technologies. Clearly, they would have to be controlled. Perhaps the best way to do so would be through the use of international uranium enrichment, reprocessing, and reactor production facilities. An additional step to ensure proliferation resistance would be internationalizing nuclear waste disposal, so that all nuclear material was controlled and accounted for from cradle to grave. The question is, how to internationalize these technologies? Who would host these facilities — and who would be dependent upon the good will of the hosts?
The problem with internationalizing these facilities is that it would create two classes of country: those deemed responsible and stable enough to host these facilities, and the rest. Furthermore, many countries find nuclear energy attractive because it allows them to become independent of others for their energy resources. Internationalizing the nuclear fuel production facilities would continue the energy dependence of many countries.
Finally, there is a problem with the large existing stocks of separated plutonium in the civilian energy sector. Over 200 tonnes of separated plutonium remains in storage in the United Kingdom, France, Russia, and other countries, with no immediate plans for its use. Though the material is (for the most part) well-guarded and accounted for, there remains the possibility of diversion or theft. These stockpiles would need to be responsibly dealt with before the step was taken of making a large expansion in nuclear power. This would increase the security of all nations by showing that there were no intentions to use this material in nuclear weapons.
Concerns about security and terrorism at nuclear power plants are not new, but they were certainly highlighted by the September 11, 2001, terrorist attacks in the United States. Nuclear power plants have two main vulnerabilities: the core of the reactor and its spent fuel pool storage. Depending on the reactor design, both can be vulnerable. Some reactors are designed with the spent fuel pools inside the containment; in other designs they are outside, with less protection against attack and more potential for radiation release. Some reactors are designed with spent fuel pools on floors above ground level. If the pool in such a reactor was damaged, it could potentially drain the cooling water, leading to a fire and fuel meltdown. The reason spent fuel pools are of concern is that they often contain many times the amount of fuel in the reactor core, and thus the potential for fire is higher in the event of sabotage.
Most nuclear reactors are facilities that restrict the persons allowed to enter. Nonetheless, the security threat exists. The threat could be from an outside attack from the air, water (many nuclear power plants are located on bodies of water), or ground and could be assisted by one or more insiders, helping from within the facility itself. The problem of security at nuclear plants is exemplified by the over 50-percent failure rate of security tests done at U.S. reactors. With a ten-fold increase in nuclear power plants, the risk from terrorist attack also increases.
Perhaps the solution to the risk is inherently safe reactors and inherently safe fuel. There are very few new reactor designs that have these qualities, though the Swedish-designed Process Inherent Ultimate Safe (PIUS) reactor may come close. There are no obvious solutions to the security problem at this time, short of guarding the facilities as nuclear weapons facilities are guarded, a proposition far too costly for the nuclear industry.
An expansion to more than 3,500 nuclear reactors worldwide implies first tackling the major issues of cost, safety, waste, proliferation, and security. The cost of nuclear power must be competitive not only with fossil fuels but also with renewable energy technologies, such as wind, that will become mature in the twenty-first century. Safety and cost are linked, and the new, safer reactor designs must prove to be cost competitive as well, in both the industrialized and developing worlds. The nuclear waste problem must be proven solvable, given the large amounts of waste expected to be produced with a tenfold increase in generating capacity. And perhaps most importantly, there must be enough international infrastructure and organization to deal with the proliferation and security issues.
One other problem will need to be solved before expanding nuclear power. Currently, there are no plans for phasing out nuclear power — decommissioning all the reactors, ensuring that no material is diverted to nuclear weapons or terrorists, and disposing of the wastes. Given that one day nuclear power will no longer be needed, how will phase-out occur with ten times as many reactors? Is it ethical to embark on such an increase without definite plans to deal with any of these issues? In comparison to coal-fired plants, where there is no worry about diversion of fuel to nuclear weapons, the problem of nuclear power phase-out is much more complicated.
Because of all the potential problems, many of them very serious, that a ten-fold increase in nuclear power will bring, a world with increased nuclear power will not be modelled on the current situation of nuclear power use. There will have to be a way to deal with the waste problem, because it will not be solved with geologic repositories — the public simply would not allow that (seeing how they have yet to allow it). If that is the case, then some type of reprocessing and/or transmutation will be required to deal with the spent fuel. And in that case, there will have to be tight controls to avoid the proliferation of nuclear weapons. Because the amount of plutonium produced in such a scenario is on the order of 150,000 bombs’ worth per year, reprocessing will need to be done in a single international centre. I suggest a single centre because the non-proliferation advantage would be lost to competition among fuel suppliers if there was more than one centre. And one centre would be the most equitable, if it were truly international.
In the end, such a large expansion in nuclear energy may only be possible if the connection between nuclear energy and nuclear weapons is fully broken. For this to be done, nuclear weapons would likely have to be abolished and sworn off by all countries. In today’s world, it is difficult to imagine such a scenario.
At this time, it is not at all clear that these issues will be resolved in the long term. If they are not, the potential for harm from reactor accidents, nuclear weapons use, or terrorist attacks will make a large expansion of this energy form undesirable, even given its beneficial effects on the climate. In the end, with nuclear power we must weigh the risks and their potentials: could there be a nuclear bomb from diverted nuclear materials, and is the explosion of one of these weapons worth the money saved from renewable energy technologies and the advantages for the climate? I’m not sure we are able to answer that question right now.