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Fukushima Daiichi Nuclear Power Plant, 2002
By Kate Marvel and Michael May
Anticipating the future is difficult in any situation, but assessing the prospects for nuclear power in the next fifty years presents especially complex challenges. The public perception of nuclear power has changed drastically since the introduction of the technology, and continues to change. Once viewed as a miracle of modern technology, nuclear power came to be perceived by many as a potential catastrophe. It is now viewed as a potential, albeit potentially dangerous, source of green power. Conventional wisdom in the 1960s held that nuclear power could dominate the electricity sectors of developed countries.
Less than twenty years later, many predicted the complete demise of the U.S. nuclear industry following the Three Mile Island accident in 1979. Yet neither attitude fully forecast the situation today: a nuclear industry that has failed to achieve market dominance, is struggling with the aftermath of the Fukushima accident, but is far from dead. Indeed, the history of long-range planning for nuclear power serves as a caution for anyone wishing to make predictions about the state of the industry over the next half-century. Nonetheless, it is critical to assess its role in the future energy mix: decisions taken now will impact the energy sector for many years. This assessment requires both a review of past planning strategies and a new approach that considers alternate scenarios that may differ radically from business as usual.
While a number of studies have explored the future of nuclear power under various circumstances, a recent study by the authors1 considers what could be potentially game changing events for nuclear energy. We take “the game” to be the current no-surprise scenario for the next fifty years: that is, a slow and uneven growth in nuclear power worldwide. Growth will be very strong in China and India, South Korea, and Russia, and sluggish in the United States and Western Europe, where current plans call for replacing, but not significantly expanding, the existing large fleets. The situation in Japan post-Fukushima is in a state of flux. This course of events will be the result of planned investments and government decisions, coupled with anticipated changes implemented over known horizons. Several variations of this scenario are accepted possibilities.
The ongoing situation at the Fukushima Daiichi Nuclear Power Station in Japan is a game changer for nuclear energy. While accidents are normal in any interaction of a complex facility and humans, they have tended to be game changers, for good and ill. The events at Fukushima were not included in planning horizons, yet they now could significantly affect the future of nuclear power. While the situation continues to evolve, a rough picture of the accident and its consequences has begun to emerge.
A magnitude 9 earthquake, coupled with a 15 meter tsunami that overflowed the seawall, resulted in the failure of the electrical systems that pumped in cooling water to the reactors, leading to overheating in both the reactor cores and spent fuel storage pools, further damage to the cooling systems and the release of large amounts of radiation. The total amount of radiation release is gradually coming into focus, with 5-month cumulative levels outside the exclusion zone ranging up to 115 millisieverts, up to and over 500 millisieverts inside the zone, and total release into the sea, due to emergency cooling with seawater, now estimated at over 15000 trillion becquerels.2
Predictably, opinion polls show a reduction in popular support for nuclear power, particularly in the United States and most of the European Union. However, in the United States, the political response has been muted, with both the Republican leadership and the White House expressing continued support for nuclear power. At the extreme ends, the German government announced it will accelerate the phase-out of nuclear power while, at the time of this writing, China remains committed under its new Five-Year Plan to a target of more than 11 percent of primary energy from nonfossil sources. Meeting that target requires a large expansion of nuclear power.
Safety Reviews. In the immediate aftermath of the crisis, most countries that currently use nuclear power are likely to undertake major reviews of reactor safety. Shortly after the incident, the U.S. Nuclear Regulatory Commission announced an immediate ninety-day review focusing on emergency procedures, to be followed by a more extensive in-depth review of all U.S. reactors. Germany has closed seven of its seventeen reactors for safety checks. China has announced a comprehensive safety review at nuclear plants in operation and under construction. These reviews are emphasizing robustness against any form of loss of cooling, including loss triggered by earthquakes and tsunamis, as well as reconsidering the physical location and operation plan for backup power supplies.
The General Electric Mark 1 Reactor Design
The Fukushima reactors were of the General Electric Mark 1 design and had been in service since the 1970s. While plants of this design have operated safely for a number of decades in a number of locations, the design does not reflect the safety improvements of more recent reactors, particularly with regard to backup cooling systems. In fact, the design has been criticized over the years on several counts, including possible rupture of the reactor containment vessel if all cooling failed and lack of containment for the highly radioactive spent fuel rods that had been removed from the reactor core and were cooling in the water pool. Some of those concerns are accentuated by the reactor’s age and the attendant material degradation. In addition, Japan’s nuclear safety agency has criticized TEPCO, the owner of the reactors, for failing to carry out required inspections of equipment, including essential elements of the cooling systems. It is not clear how much this failure affected the disaster.
Thirty-two reactors of the same type as those at Fukushima are in use in several countries, including twenty-three in the United States. A number have received or are currently being considered for license extensions beyond their original planned lifetime.3
Spent Fuel Storage
Some of the most severe consequences of the Fukushima accident resulted from a loss-of-coolant failure in the spent fuel pools. This possibility has focused attention on the storage and disposal of reactor spent fuel. There are three relevant timescales to consider: short-term storage, where spent fuel must be cooled following its removal from the reactor; medium-term storage, where spent fuel is stored in dry casks, usually on-site; and long-term disposal, which will likely require a geologic repository. Initial reviews are focusing on the immediate hazards of cooling spent fuel once it is removed from the reactor, with special attention paid not only to protecting and containing the spent fuel that is cooling in ponds but also to large amounts of older but still radioactive spent fuel stored in casks, as is the case in the United States, where no longer-term storage or disposal has been approved.
More than the Usual Suspects
The accident at Fukushima will have implications worldwide, but the effects are likely to differ from country to country and region to region. Development in the United States and the European Union has been slow, with the vast majority of added nuclear capacity taking the form of license extensions and renewals. The future of nuclear power will be determined largely by the countries with the most ambitious nuclear development plans: China, India, Russia, South Korea, and to a lesser extent, Brazil, Argentina, and perhaps South Africa. This realignment of the global nuclear future is significant, possibly diminishing the influence of the traditional nuclear powers. The policies of the United States and the European Union may have less influence on the development plans of the rest of the world.
The Fukushima disaster may impact the future of nuclear power more than either the Three Mile Island or Chernobyl accidents. The Three Mile Island accident was contained without public health effects, while the Chernobyl accident involved a Soviet reactor of a model that was not used in the West and that lacked a crucial containment feature. The Fukushima accident, on the other hand, occurred in one of the most technologically advanced countries in the world and one with among the most nuclear experience. Furthermore, it was caused by a tsunami–a worrying aspect, given that many reactors in the world, including practically all of China’s reactors, are located by the sea. Moreover, it is the first nuclear disaster to occur in the Internet age, and information, rumors, and speculation have been reported to a wider audience than ever before.
How will the incident in Japan change the balance between the advantages and drawbacks of nuclear power? Given the developing situation, it is too early to make accurate forecasts of its ramifications; but indications are that the specific political and economic situations of individual countries will dominate their responses. We have noted the early actions of China and the United States. France, South Korea, and other countries that are highly dependent on nuclear-generated electricity have little option but to continue along the nuclear path, at least until new technologies are developed.
Germany, however, is an important exception. Its decision to abandon nuclear power is consistent with the country’s stated aim to phase out alternatives in favor of renewable sources, but it is unclear that wind, solar, and tidal power can compensate for shuttered nuclear plants in the near term. As a result, unless extremely ambitious goals for development, grid integration, and storage are met, Germany’s nuclear future may be replaced by a coal-dependent one. Japan, while heavily dependent on nuclear power, is likely to be strongly affected, perhaps leading to changes in the leadership and regulation of the nuclear industry, as well as changes in such aspects as siting, reliance on seawalls, and location of backup cooling systems. In the longer term, advanced designs that have stronger safety features, and that are less dependent on the operation of backup systems in an emergency, will see their advantage over early designs increase.
It is not possible to anticipate or prevent all accidents, but it is noteworthy that most of the serious accidents that have affected the nuclear industry had earlier, less destructive precursors and were anticipated by engineers, operators, or managers, yet were not prevented. This fact is specifically true in the case of Fukushima: in an earlier incident at Le Blayais in France, the seawall was overrun and some low-lying pumps and generators were flooded, though without release of radiation.4 Japan’s nuclear safety agency had also warned against siting the backup generators on low ground.
The cost of prevention in most cases would have been small, not only compared with the cost in dollars and political support of the most expensive accidents, but also compared with the overall cost of nuclear power. Thus, a major lesson from Fukushima and previous accidents or near-accidents concerns the management and supervision of the nuclear industry and the political and economic set of incentives involved. While this and other lessons tend to be reasonably well internalized within the countries where accidents have occurred, instilling them across national boundaries has been far less successful, a matter of some concern in view of the new entrants into the nuclear power field.
Over the next few months and years, as the details of the Fukushima accident become clearer, they will affect and inform the continuing conversation about the role nuclear energy will play in the future energy mix. Undoubtedly, the competitors to nuclear power, in both the present world and a possible future world where greenhouse gas emissions are taxed or regulated, have been at least temporarily strengthened by the event. For the longer term, while economic factors will continue to play a major role, the perceived likelihood of severe accidents will affect the political acceptability of nuclear power, particularly if it becomes clear that most such accidents can be prevented.
Kate Marvel is currently a postdoctoral researcher at the Carnegie Department of Global Ecology. Michael May is Professor Emeritus (Research) at Stanford University and Director Emeritus, Lawrence Livermore National Laboratory.
1.Kate Marvel and Michael May, Game Changers for Nuclear Energy (Cambridge, Mass.: American Academy of Arts and Sciences, 2011).
2.“Sea radiation from Fukushima seen triple Tepco estimate” Reuters September 9, 2011; Also “Map shows spot with high level of radiation near Fukushima plant,” Mainichi Daily News, September 12, 2011
3.“For details, see Fact Sheet on Reactor License Renewal. Other pages on the Nuclear Regulatory Commission website give the location of the units and additional relevant information” occurs on page 2 at word # 1090 “... lifetime.”
4. A. Gorbatchev*, J.M. Mattéi*, V. Rebour*, E. Vial*, “Report on flooding of Le Blayais power plant on 27 December 1999” (2000) *Institute for Protection and Nuclear Safety (IPSN), B.P. 6, 92265 Fontenay-aux-Roses cedex France; and from Eric de Fraguier, EDF Nuclear Engineering Division, “Lessons Learned From 1999 Blayais Flood: Overview Of EDF Flood Risk Management Plan” USNRC RIC-2010, 11 March 2010
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