- Email: [email protected]
The future of nuclear energy
Fuel Processing Technology 71 Ž2001. 197–204 www.elsevier.comrlocaterfuproc
The future of nuclear energy John I. Sackett ) Argonne National Laboratory, P.O. Box 2528, Idaho Falls, ID 83403-2528 USA
Abstract Nothing will be as important to the people of the world in the next century and beyond as energy to provide clean water and electricity. But how will this need be met with the increasingly recognized need to substantially reduce carbon dioxide emissions? Nuclear power provides a compelling option, but it must meet certain requirements in order to gain public and political support. In this paper, those requirements are examined and the imperative for continued research into advanced nuclear power technologies is discussed. Published by Elsevier Science B.V. Keywords: Nuclear; Technology; Energy
1. A perspective on nuclear power development Nuclear power started with the discoveries before and during World War II, a remarkable time in our history. The defining event took place at the University of Chicago on December 2, 1942 when it was demonstrated that the nuclear fission reaction, with its release of enormous amounts of energy, could be sustained and controlled. This demonstration ushered in the nuclear age. Following World War II, the United States government and the University of Chicago organized Argonne National Laboratory ŽANL. to continue research into peaceful uses of this awesome power. ANL’s first director, Walter Zinn, soon identified the need for a remote site that could host the construction of experimental nuclear power plants w1x. After a search that included candidate sites in Idaho and Montana, the site in Idaho was established as the National Reactor Testing Station in 1949. The first reactors built in Idaho were the Experimental Breeder Reactor I ŽEBR-I., which was the first
)
Fax: q1-208-533-7249.
0378-3820r01r$ - see front matter. Published by Elsevier Science B.V. PII: S 0 3 7 8 - 3 8 2 0 Ž 0 1 . 0 0 1 4 7 - 3
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J.I. Sackettr Fuel Processing Technology 71 (2001) 197–204
reactor to operate in Idaho and the first in the world to produce electricity, the prototype reactor for the Nautilus submarine, and the Materials Test Reactor ŽMTR.. The construction and operation of the Boiling Water Reactor Experiment ŽBORAX. soon followed, which eventually tied into the grid and made Arco, Idaho the first town in the world to be lit with nuclear energy. From this simple beginning—a string of eight dim light bulbs and 4 h of power to a small desert town—nuclear power has grown to account for about 17% of the electric energy production world wide with more than 400 plants in operation w2x. In the United States, there are more than 100 plants in operation, accounting for nearly 20% of our electric power production w3x. It is important that even though there have been no new nuclear plants built in the last 15 years, we as a nation have been able to meet our growth in electric energy consumption primarily because of improvements in the efficiency and reliability of operation of nuclear power plants. They are now on-line, producing power, close to 80% of the time, up from 58% just 20 years ago w4x. The point is that despite all of the negative press, commercial reactors are operating very well and are an increasingly important part of our energy mix. Nuclear power is important not only for the economic benefit, but also for environmental benefits. The reactor designs currently in use evolved from work primarily associated with what was done for the Navy. Following World War II and through the 50s, the Navy was exploring the use of different reactor types and designs for its growing fleet of nuclear powered ships w1x. The primary companies doing this work were Westinghouse and General Electric. The Navy considered pressurized water reactors, boiling water reactors, and liquid metal reactors, and eventually chose the pressurized water reactor for reasons having to do with safety and operation while at sea. Westinghouse and GE’s early reactor development work, therefore, concentrated on the water-cooled reactor types. When the time came to develop land-based commercial reactors for electricity production, the water-cooled reactors already developed for naval propulsion were the only reactor technology design that was sufficiently mature for commercial implementation. Most commercial reactors today are water-cooled. The present reactor designs utilize only a fraction of the available fuel, less than 1%, with the remainder discarded as Aspent fuel.B As the energy needs grow, this spent fuel waste problem will likely mean that different reactor designs will take the place of the current generation reactors. Other reactor designs have been used around the world, but none as extensively as the water-cooled reactors. The other reactor designs currently in operation include gas-cooled reactors, sodium-cooled reactors, and the Chernobyl type reactors that are a derivative from the Russian weapons program. None of these reactor types has been deployed as extensively as the water-cooled reactor designs. Of the currently operating reactor designs, only the few operating sodium-cooled reactors Žcommonly referred to as breeder reactors. are of a type that can greatly extend the available fuel supply. It is worth noting that the operating, maintenance and fuel costs of the existing reactors are competitive with gas, oil and coal-fired electrical generation Že.g., Ref. w5x.. When the exorbitant debt payments needed to amortize the construction and capitol improvement costs are included, however, the current fleet of nuclear power generators is not competitive. It was expected that the cheaper fuel costs of nuclear power would have made it more competitive with fossil fuel energy sources. However, the expected
J.I. Sackettr Fuel Processing Technology 71 (2001) 197–204
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escalation of fossil fuel cost that motivated the electrical industry to go nuclear simply did not materialize, and construction costs and the accommodation of licensing requirements made nuclear power more costly. This country is now proceeding to deregulate the traditional utility companies, leading many of them to sell off their generation assets, including their nuclear units. These sales are resulting in sizeable write-downs of the construction debt, and essentially revaluing the plants at today’s market prices. This makes them competitive in the deregulated market. For example, in July 1999, the auction sale of the Pilgrim Nuclear Power Station closed at $25 million for a plant that cost nearly $1 billion to build. Pilgrim is now operating profitably by Entergy Nuclear in the deregulated power market of Massachusetts. There are several companies like Entergy that are active in purchasing and consolidating the country’s nuclear assets. As a result, one of the nuclear industry’s early problems, the ownership of reactors by well meaning but technically inadequate utilities, is being solved. A few large, competent nuclear operating companies are emerging that will own and operate the current fleet of nuclear plants over the next several decades, and it is expected that operating efficiency of these plants will improve. While existing reactors are increasingly competitive, the question is whether new, more modern reactor designs could be economically competitive. Today, nuclear power utilization is on a plateau. Some new plants of an updated design are being built—all outside the United States—and roughly an equal number of older plants are being retired and decommissioned. Legacy issues, such as waste disposal, contaminated enrichment facilities, and low power plant reliability are being addressed. Public opposition that reached a peak following the accident at Chernobyl has subsided, and a recent poll of Americans shows that the majority wants and expects nuclear power to be a part of the US’ future electricity generation mix. The world’s population has reached 6 billion people and is projected to reach 10 billion in the next century. More than 30% live in poverty without access to electricity. Their life span averages less than 40 years. With access to even a modest amount of electricity and the benefits it brings, the data show that life span increases dramatically, to about 65 years. Significantly, the quality of life also increases dramatically. Energy is fundamental to improving the quality of peoples’ lives. Deregulation is spurring much innovation in the power generation business, favoring small distributed generating sources that may well be suitable for deployment in many of these developing nations as their economies begin to expand. Natural gas will grow in importance, particularly in the United States. But many countries do not have access to gas, the infrastructure to support it, or either. Electricity can be produced by many means, but only nuclear, coal and natural gas together have the potential to meet the needs of the next century, driven by the rapid growth of developing countries. Demand for electricity is conservatively predicted to triple by the middle of the next century w6x. Some would say that we cannot afford such growth. However, we cannot deny to the growing population of the world the benefits of a higher standard of living. Just as important, it has been demonstrated over and over again that countries with high standards of living have low population growth and less environmental degradation. So, in addition to improving the lives of individual people, such economic growth can also benefit the globe environmentally. That is really the key question: can we manage
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energy growth in a way that can meet the needs of a hungry world, stabilize economies and protect the environment? This is a challenge worthy of us all. Coal, in its present form, is not an ideal solution for a simple reason: air pollution and global warming. The science to predict effects of CO 2 emission is still immature, and there is much uncertainty, but if the predictions are correct, it will have profound effects on climate, even at current levels of emissions. Evidence increasingly supports the concern that global temperatures are increasing and that we will see the effects of human activity on global climate. What those effects will be and how to address them are the present questions. There is talk of CO 2 sequestering, but the required technology is far-off. The use of natural gas can help, but it, too, produces a CO 2 by-product. We can talk about energy conservation, but that is for the developed nations, not the developing nations. We can talk about new technologies, solar, biomass, etc., and they have their place, but they have a very limited capacity and will play only a small part. For nuclear to provide even one-third of the carbon-free energy supply necessary to stabilize CO 2 levels, it would require building the equivalent of 100 large plants per year, starting now. If nuclear power is to play an essential part in addressing the greenhouse problem, slow, steady growth will not be sufficient.
2. The challenges for nuclear power The challenges for nuclear power are fourfold: Ž1. nuclear power must first of all be economically competitive; Ž2. waste products from the nuclear fuel cycle must be manageable; Ž3. the public must have confidence in the safety of operating nuclear power plants and associated supporting facilities; and Ž4. weapon-usable materials must be properly managed and safeguarded to ensure that no material is diverted to nuclear weapons. I now elaborate on each of these challenges. 2.1. Economics Any power source must make sense in a competitive market. Nuclear power suffers from the fact that each plant built in this country was one of a kind, with only a few exceptions. Further, each one had to be of best possible construction to satisfy safety requirements, requirements which were continually being changed through the early years of development. The designs resulted in increased capital costs and very large staffing requirements, driving up the cost of electricity. The automobile industry could not succeed on a broad scale until it moved away from hand-building individual luxury cars and moved toward mass production of vehicles that comply with known and accepted standards. The same applies to nuclear plants. The cars of today are vastly superior in every respect, especially safety, to those that preceded them. They are a great value. The same must happen with nuclear power. Smaller, modular plants produced in factories are part of the answer. Standardization of a few designs is another part of the answer. Surprisingly, cheaper and simpler can also mean safer.
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2.2. Waste management Management of nuclear waste is an issue dominated by emotional considerations. To this end, the permanent repository at Yucca Mountain in Nevada is intended to permanently isolate materials from the biosphere, for a million years or more. There is currently an intense debate in Congress over employing interim storage instead of permanent burial. Transmutation of the waste, using reactors or accelerators is also being considered in the US and other countries. Internationally, several studies are considering improved methods of fuel management that include recycle. One thing is clear: burning less than 1% of the available fuel and discarding the rest, as we currently do, is bound to create a waste problem. To this end, many nations are considering means to recycle long-lived components of spent LWR fuel Ži.e., actinides. into proliferationresistant reactors and fuel cycles that will fission those isotopes into short-lived isotopes. We can expect other international initiatives to develop, such as deep-burn reactors and other concepts that more fully use the fuel without requiring recycling. 2.3. Safety The enemy of safety is complexity. Our nuclear plants have become increasingly complex, in part, ironically, because of the addition of many safety systems. Although it is often more expedient to engineer a safety fix with the addition of a new system, I think we need to return to the fundamental design of the reactor and take advantage of the inherent physics to ensure that it will respond safely. It is possible to design an aircraft that can glide after the engines are lost, and to stall at such a slow speed that it can be landed safely on rough terrain. Likewise, it is possible to design a reactor that will inherently decrease power after losing all electrical power, without requiring active safety systems. This concept was proven at Argonne in 1986, when all safety systems and cooling systems on the Experimental Breeder Reactor-II were disabled at full power w7x. Because this reactor employed inherent safety in its design, the reactor power decreased safely, and the reactor never overheated. Such features are being incorporated into the newest reactor designs and concepts. One benefit is that their safety systems can then be simplified, and costs reduced. This is a field of research and development with great promise for the future. Existing commercial reactors in the United States and elsewhere are safe, and new designs will be safer still. Yet, there are reactors operating in many countries of the former Soviet Union that must be monitored carefully to avoid another accident on the scale of Chernobyl. Many have no containment vessels and inadequate emergency core cooling systems. Such issues as these must be addressed; the United States must provide the leadership to do so. 2.4. Proliferation of weapons material A requirement for substantial growth of nuclear power is to prevent the proliferation of material that could be diverted to use in nuclear weapons. This is probably the
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greatest fear of those in the US who strongly oppose nuclear power, especially its use in developing countries. It is such an emotional issue that there is talk about putting the genie back in the bottle, walking away from the technology. Our present problem is that nuclear power grew out of the weapon programs of Russia and the United States and these technologies are perceived as being closely linked. We can do better. The first step is to burn down, to destroy, and to eliminate the excess weapons material that we currently have available. Reducing the inventories will greatly assist in managing the material that remains. Simply speaking, if the remaining material is locked away in reactor systems to be destroyed, it cannot be used for weapons. Even more importantly, it can easily be monitored. What we need are reactor systems and associated fuel cycles that make extremely difficult or impossible the diversion of material to weapon use. And we need the monitoring systems to make any attempt at diversion obvious to all.
3. The future for nuclear power 3.1. AdÕanced reactor deÕelopment We are then confronted with the challenges of economics, safety, waste and proliferation. These are not new challenges. We addressed them at Argonne in the early 80s with the development of the Integral Fast Reactor ŽIFR. concept w8x, and created a great deal of excitement in the process. We demonstrated that a proliferation-resistant fuel cycle, that is transparent for those who would monitor it, could be developed. We demonstrated that fuel could be recycled to the reactor, so that fuel and fission products could be burned, not added to the waste and buried. We demonstrated that we could simplify the design, greatly improving the economics. And we demonstrated that safety could be assured through the proper use of natural physical principles. In short, the IFR program was a great technical success. It made significant progress in both defining the questions to be asked and in answering them. Even though the IFR was terminated for political reasons in 1994, it has laid the groundwork for important work in the future. Similar characteristics are now being incorporated into concepts being developed in the international arena. I expect that the next major activity in nuclear reactor deployment will build upon the existing systems for which we have a great deal of experience, and for which improved designs have already been developed ŽAGeneration-IIIB reactor designs, commonly referred to as advanced light water reactors.. They involve both pressurized water and boiling water reactor systems. These plants incorporate many of the improvements described above, especially those related to safety and economics. Examples of these plants are currently being built in Japan and will further enhance the ability to build more when the demand develops. This is an evolutionary step not unlike how other major technical advances have been pursued in aviation or automotive fields. However, there is also the opportunity for a revolutionary step, to what are being referred to as AGeneration-IVB designs, not unlike the move of the aviation industry from propellerdriven airplanes to jets.
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It is important that the United States maintain its expertise if it is to maintain international leadership for the stewardship of existing plants and the building of new plants. Problems will arise and it is important that we are able to deal with them. Developing nations will turn to nuclear power to improve the lives of their people, and it is important that we are sufficiently engaged with the technology to ensure that this is done in a safe and secure manner. The only way for other nations to respect the United States as a leader in policy is to be a leader in the technology. Fortunately, there are important initiatives emerging. Congress has funded the Nuclear Engineering Research Institute ŽNERI. at about $20 million annually, a relatively low level, but an important beginning. The funds support a number of nascent, innovative research initiatives from universities and national laboratories to develop new approaches to nuclear reactor design, among other things. The DOE is also taking leadership in drawing other countries together to pursue extremely innovative, Generation-IV concepts. Let me describe one such initiative. There is being developed a water-cooled reactor with a core that is envisioned to operate for 14 years without refueling. At 14 years, the whole core will be replaced. Because there is no need for refueling, there is no need for a refueling system and the cost it entails. Because there is no movement of fuel, there is no risk of diversion of material. Such designs are possible and have captured the imagination of an international audience. In the example mentioned for a light water reactor design, the French and the Japanese are participating. Another reactor design, a pebble-bed gas-cooled reactor, has attracted an even broader international audience. Also, there is resurgent interest in liquid metal-cooled reactors. At the present moment, the US is not committed to any particular line of advanced reactor development. This, along with initiatives such as NERI, allows technologists to rethink how the atom can best be harnessed. Previous experience with advanced reactor and fuel cycle development has identified sound concepts for addressing concerns over economics, waste management, safety and proliferation. The challenge is to improve these concepts and incorporate them all into a system that is sufficiently attractive, that it will be selected for deployment over less-desirable options.
4. Conclusion We can all be thankful for nuclear power, for it may well be essential to the long-term survival of civilization. Within the seeds of its potential for great good, are also the seeds for great harm. We must ensure that it is applied for great good. What is not in question is whether we can live without it, we cannot. United States leadership is crucial in determining how this technology is developed and applied. The size and capability of the United States’ technical community is decreasing, a trend that cannot be allowed to continue. It is my belief that in the future, the need, the vision and the confidence in nuclear power will be restored, but only if we address the immediate challenges before us. It is a national challenge worthy of the best people this nation has to offer.
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References w1x J.M. Holl, Argonne National Laboratory, 1946–96. University of Illinois Press, 1997. w2x M. Damian, Atoms in flux. Forum for Applied Research and Public Policy, Executive Sciences Institute, Davenport, IA, Spring 1996, p. 88. w3x Nuclear Energy Institute, Meeting Our Clean-Air Needs with Emission-Free Generation, May, 1999. w4x Nuclear Energy Institute, Nuclear Power Plant Performance, September, 1999. w5x Nucleonics Week, 40, Ž27. Ž1999. July 8. w6x British Petroleum Company PLC, BP Statistical Review of World Energy. Brittanic House, London, 1998. w7x The experimental breeder reactor-II inherent safety demonstration, in: S.H. Fistedis ŽEd.., Nuclear Engineering and Design, vol. 101 Ž1. Ž1987.. w8x The technology of the integral fast reactor and its associated fuel cycle, in: W.H. Hannum ŽEd.., Progress in Nuclear Energy, vol. 31 Ž1r2. Ž1997..
The future of nuclear energy John I. Sackett ) Argonne National Laboratory, P.O. Box 2528, Idaho Falls, ID 83403-2528 USA
Abstract Nothing will be as important to the people of the world in the next century and beyond as energy to provide clean water and electricity. But how will this need be met with the increasingly recognized need to substantially reduce carbon dioxide emissions? Nuclear power provides a compelling option, but it must meet certain requirements in order to gain public and political support. In this paper, those requirements are examined and the imperative for continued research into advanced nuclear power technologies is discussed. Published by Elsevier Science B.V. Keywords: Nuclear; Technology; Energy
1. A perspective on nuclear power development Nuclear power started with the discoveries before and during World War II, a remarkable time in our history. The defining event took place at the University of Chicago on December 2, 1942 when it was demonstrated that the nuclear fission reaction, with its release of enormous amounts of energy, could be sustained and controlled. This demonstration ushered in the nuclear age. Following World War II, the United States government and the University of Chicago organized Argonne National Laboratory ŽANL. to continue research into peaceful uses of this awesome power. ANL’s first director, Walter Zinn, soon identified the need for a remote site that could host the construction of experimental nuclear power plants w1x. After a search that included candidate sites in Idaho and Montana, the site in Idaho was established as the National Reactor Testing Station in 1949. The first reactors built in Idaho were the Experimental Breeder Reactor I ŽEBR-I., which was the first
)
Fax: q1-208-533-7249.
0378-3820r01r$ - see front matter. Published by Elsevier Science B.V. PII: S 0 3 7 8 - 3 8 2 0 Ž 0 1 . 0 0 1 4 7 - 3
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J.I. Sackettr Fuel Processing Technology 71 (2001) 197–204
reactor to operate in Idaho and the first in the world to produce electricity, the prototype reactor for the Nautilus submarine, and the Materials Test Reactor ŽMTR.. The construction and operation of the Boiling Water Reactor Experiment ŽBORAX. soon followed, which eventually tied into the grid and made Arco, Idaho the first town in the world to be lit with nuclear energy. From this simple beginning—a string of eight dim light bulbs and 4 h of power to a small desert town—nuclear power has grown to account for about 17% of the electric energy production world wide with more than 400 plants in operation w2x. In the United States, there are more than 100 plants in operation, accounting for nearly 20% of our electric power production w3x. It is important that even though there have been no new nuclear plants built in the last 15 years, we as a nation have been able to meet our growth in electric energy consumption primarily because of improvements in the efficiency and reliability of operation of nuclear power plants. They are now on-line, producing power, close to 80% of the time, up from 58% just 20 years ago w4x. The point is that despite all of the negative press, commercial reactors are operating very well and are an increasingly important part of our energy mix. Nuclear power is important not only for the economic benefit, but also for environmental benefits. The reactor designs currently in use evolved from work primarily associated with what was done for the Navy. Following World War II and through the 50s, the Navy was exploring the use of different reactor types and designs for its growing fleet of nuclear powered ships w1x. The primary companies doing this work were Westinghouse and General Electric. The Navy considered pressurized water reactors, boiling water reactors, and liquid metal reactors, and eventually chose the pressurized water reactor for reasons having to do with safety and operation while at sea. Westinghouse and GE’s early reactor development work, therefore, concentrated on the water-cooled reactor types. When the time came to develop land-based commercial reactors for electricity production, the water-cooled reactors already developed for naval propulsion were the only reactor technology design that was sufficiently mature for commercial implementation. Most commercial reactors today are water-cooled. The present reactor designs utilize only a fraction of the available fuel, less than 1%, with the remainder discarded as Aspent fuel.B As the energy needs grow, this spent fuel waste problem will likely mean that different reactor designs will take the place of the current generation reactors. Other reactor designs have been used around the world, but none as extensively as the water-cooled reactors. The other reactor designs currently in operation include gas-cooled reactors, sodium-cooled reactors, and the Chernobyl type reactors that are a derivative from the Russian weapons program. None of these reactor types has been deployed as extensively as the water-cooled reactor designs. Of the currently operating reactor designs, only the few operating sodium-cooled reactors Žcommonly referred to as breeder reactors. are of a type that can greatly extend the available fuel supply. It is worth noting that the operating, maintenance and fuel costs of the existing reactors are competitive with gas, oil and coal-fired electrical generation Že.g., Ref. w5x.. When the exorbitant debt payments needed to amortize the construction and capitol improvement costs are included, however, the current fleet of nuclear power generators is not competitive. It was expected that the cheaper fuel costs of nuclear power would have made it more competitive with fossil fuel energy sources. However, the expected
J.I. Sackettr Fuel Processing Technology 71 (2001) 197–204
199
escalation of fossil fuel cost that motivated the electrical industry to go nuclear simply did not materialize, and construction costs and the accommodation of licensing requirements made nuclear power more costly. This country is now proceeding to deregulate the traditional utility companies, leading many of them to sell off their generation assets, including their nuclear units. These sales are resulting in sizeable write-downs of the construction debt, and essentially revaluing the plants at today’s market prices. This makes them competitive in the deregulated market. For example, in July 1999, the auction sale of the Pilgrim Nuclear Power Station closed at $25 million for a plant that cost nearly $1 billion to build. Pilgrim is now operating profitably by Entergy Nuclear in the deregulated power market of Massachusetts. There are several companies like Entergy that are active in purchasing and consolidating the country’s nuclear assets. As a result, one of the nuclear industry’s early problems, the ownership of reactors by well meaning but technically inadequate utilities, is being solved. A few large, competent nuclear operating companies are emerging that will own and operate the current fleet of nuclear plants over the next several decades, and it is expected that operating efficiency of these plants will improve. While existing reactors are increasingly competitive, the question is whether new, more modern reactor designs could be economically competitive. Today, nuclear power utilization is on a plateau. Some new plants of an updated design are being built—all outside the United States—and roughly an equal number of older plants are being retired and decommissioned. Legacy issues, such as waste disposal, contaminated enrichment facilities, and low power plant reliability are being addressed. Public opposition that reached a peak following the accident at Chernobyl has subsided, and a recent poll of Americans shows that the majority wants and expects nuclear power to be a part of the US’ future electricity generation mix. The world’s population has reached 6 billion people and is projected to reach 10 billion in the next century. More than 30% live in poverty without access to electricity. Their life span averages less than 40 years. With access to even a modest amount of electricity and the benefits it brings, the data show that life span increases dramatically, to about 65 years. Significantly, the quality of life also increases dramatically. Energy is fundamental to improving the quality of peoples’ lives. Deregulation is spurring much innovation in the power generation business, favoring small distributed generating sources that may well be suitable for deployment in many of these developing nations as their economies begin to expand. Natural gas will grow in importance, particularly in the United States. But many countries do not have access to gas, the infrastructure to support it, or either. Electricity can be produced by many means, but only nuclear, coal and natural gas together have the potential to meet the needs of the next century, driven by the rapid growth of developing countries. Demand for electricity is conservatively predicted to triple by the middle of the next century w6x. Some would say that we cannot afford such growth. However, we cannot deny to the growing population of the world the benefits of a higher standard of living. Just as important, it has been demonstrated over and over again that countries with high standards of living have low population growth and less environmental degradation. So, in addition to improving the lives of individual people, such economic growth can also benefit the globe environmentally. That is really the key question: can we manage
200
J.I. Sackettr Fuel Processing Technology 71 (2001) 197–204
energy growth in a way that can meet the needs of a hungry world, stabilize economies and protect the environment? This is a challenge worthy of us all. Coal, in its present form, is not an ideal solution for a simple reason: air pollution and global warming. The science to predict effects of CO 2 emission is still immature, and there is much uncertainty, but if the predictions are correct, it will have profound effects on climate, even at current levels of emissions. Evidence increasingly supports the concern that global temperatures are increasing and that we will see the effects of human activity on global climate. What those effects will be and how to address them are the present questions. There is talk of CO 2 sequestering, but the required technology is far-off. The use of natural gas can help, but it, too, produces a CO 2 by-product. We can talk about energy conservation, but that is for the developed nations, not the developing nations. We can talk about new technologies, solar, biomass, etc., and they have their place, but they have a very limited capacity and will play only a small part. For nuclear to provide even one-third of the carbon-free energy supply necessary to stabilize CO 2 levels, it would require building the equivalent of 100 large plants per year, starting now. If nuclear power is to play an essential part in addressing the greenhouse problem, slow, steady growth will not be sufficient.
2. The challenges for nuclear power The challenges for nuclear power are fourfold: Ž1. nuclear power must first of all be economically competitive; Ž2. waste products from the nuclear fuel cycle must be manageable; Ž3. the public must have confidence in the safety of operating nuclear power plants and associated supporting facilities; and Ž4. weapon-usable materials must be properly managed and safeguarded to ensure that no material is diverted to nuclear weapons. I now elaborate on each of these challenges. 2.1. Economics Any power source must make sense in a competitive market. Nuclear power suffers from the fact that each plant built in this country was one of a kind, with only a few exceptions. Further, each one had to be of best possible construction to satisfy safety requirements, requirements which were continually being changed through the early years of development. The designs resulted in increased capital costs and very large staffing requirements, driving up the cost of electricity. The automobile industry could not succeed on a broad scale until it moved away from hand-building individual luxury cars and moved toward mass production of vehicles that comply with known and accepted standards. The same applies to nuclear plants. The cars of today are vastly superior in every respect, especially safety, to those that preceded them. They are a great value. The same must happen with nuclear power. Smaller, modular plants produced in factories are part of the answer. Standardization of a few designs is another part of the answer. Surprisingly, cheaper and simpler can also mean safer.
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201
2.2. Waste management Management of nuclear waste is an issue dominated by emotional considerations. To this end, the permanent repository at Yucca Mountain in Nevada is intended to permanently isolate materials from the biosphere, for a million years or more. There is currently an intense debate in Congress over employing interim storage instead of permanent burial. Transmutation of the waste, using reactors or accelerators is also being considered in the US and other countries. Internationally, several studies are considering improved methods of fuel management that include recycle. One thing is clear: burning less than 1% of the available fuel and discarding the rest, as we currently do, is bound to create a waste problem. To this end, many nations are considering means to recycle long-lived components of spent LWR fuel Ži.e., actinides. into proliferationresistant reactors and fuel cycles that will fission those isotopes into short-lived isotopes. We can expect other international initiatives to develop, such as deep-burn reactors and other concepts that more fully use the fuel without requiring recycling. 2.3. Safety The enemy of safety is complexity. Our nuclear plants have become increasingly complex, in part, ironically, because of the addition of many safety systems. Although it is often more expedient to engineer a safety fix with the addition of a new system, I think we need to return to the fundamental design of the reactor and take advantage of the inherent physics to ensure that it will respond safely. It is possible to design an aircraft that can glide after the engines are lost, and to stall at such a slow speed that it can be landed safely on rough terrain. Likewise, it is possible to design a reactor that will inherently decrease power after losing all electrical power, without requiring active safety systems. This concept was proven at Argonne in 1986, when all safety systems and cooling systems on the Experimental Breeder Reactor-II were disabled at full power w7x. Because this reactor employed inherent safety in its design, the reactor power decreased safely, and the reactor never overheated. Such features are being incorporated into the newest reactor designs and concepts. One benefit is that their safety systems can then be simplified, and costs reduced. This is a field of research and development with great promise for the future. Existing commercial reactors in the United States and elsewhere are safe, and new designs will be safer still. Yet, there are reactors operating in many countries of the former Soviet Union that must be monitored carefully to avoid another accident on the scale of Chernobyl. Many have no containment vessels and inadequate emergency core cooling systems. Such issues as these must be addressed; the United States must provide the leadership to do so. 2.4. Proliferation of weapons material A requirement for substantial growth of nuclear power is to prevent the proliferation of material that could be diverted to use in nuclear weapons. This is probably the
202
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greatest fear of those in the US who strongly oppose nuclear power, especially its use in developing countries. It is such an emotional issue that there is talk about putting the genie back in the bottle, walking away from the technology. Our present problem is that nuclear power grew out of the weapon programs of Russia and the United States and these technologies are perceived as being closely linked. We can do better. The first step is to burn down, to destroy, and to eliminate the excess weapons material that we currently have available. Reducing the inventories will greatly assist in managing the material that remains. Simply speaking, if the remaining material is locked away in reactor systems to be destroyed, it cannot be used for weapons. Even more importantly, it can easily be monitored. What we need are reactor systems and associated fuel cycles that make extremely difficult or impossible the diversion of material to weapon use. And we need the monitoring systems to make any attempt at diversion obvious to all.
3. The future for nuclear power 3.1. AdÕanced reactor deÕelopment We are then confronted with the challenges of economics, safety, waste and proliferation. These are not new challenges. We addressed them at Argonne in the early 80s with the development of the Integral Fast Reactor ŽIFR. concept w8x, and created a great deal of excitement in the process. We demonstrated that a proliferation-resistant fuel cycle, that is transparent for those who would monitor it, could be developed. We demonstrated that fuel could be recycled to the reactor, so that fuel and fission products could be burned, not added to the waste and buried. We demonstrated that we could simplify the design, greatly improving the economics. And we demonstrated that safety could be assured through the proper use of natural physical principles. In short, the IFR program was a great technical success. It made significant progress in both defining the questions to be asked and in answering them. Even though the IFR was terminated for political reasons in 1994, it has laid the groundwork for important work in the future. Similar characteristics are now being incorporated into concepts being developed in the international arena. I expect that the next major activity in nuclear reactor deployment will build upon the existing systems for which we have a great deal of experience, and for which improved designs have already been developed ŽAGeneration-IIIB reactor designs, commonly referred to as advanced light water reactors.. They involve both pressurized water and boiling water reactor systems. These plants incorporate many of the improvements described above, especially those related to safety and economics. Examples of these plants are currently being built in Japan and will further enhance the ability to build more when the demand develops. This is an evolutionary step not unlike how other major technical advances have been pursued in aviation or automotive fields. However, there is also the opportunity for a revolutionary step, to what are being referred to as AGeneration-IVB designs, not unlike the move of the aviation industry from propellerdriven airplanes to jets.
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It is important that the United States maintain its expertise if it is to maintain international leadership for the stewardship of existing plants and the building of new plants. Problems will arise and it is important that we are able to deal with them. Developing nations will turn to nuclear power to improve the lives of their people, and it is important that we are sufficiently engaged with the technology to ensure that this is done in a safe and secure manner. The only way for other nations to respect the United States as a leader in policy is to be a leader in the technology. Fortunately, there are important initiatives emerging. Congress has funded the Nuclear Engineering Research Institute ŽNERI. at about $20 million annually, a relatively low level, but an important beginning. The funds support a number of nascent, innovative research initiatives from universities and national laboratories to develop new approaches to nuclear reactor design, among other things. The DOE is also taking leadership in drawing other countries together to pursue extremely innovative, Generation-IV concepts. Let me describe one such initiative. There is being developed a water-cooled reactor with a core that is envisioned to operate for 14 years without refueling. At 14 years, the whole core will be replaced. Because there is no need for refueling, there is no need for a refueling system and the cost it entails. Because there is no movement of fuel, there is no risk of diversion of material. Such designs are possible and have captured the imagination of an international audience. In the example mentioned for a light water reactor design, the French and the Japanese are participating. Another reactor design, a pebble-bed gas-cooled reactor, has attracted an even broader international audience. Also, there is resurgent interest in liquid metal-cooled reactors. At the present moment, the US is not committed to any particular line of advanced reactor development. This, along with initiatives such as NERI, allows technologists to rethink how the atom can best be harnessed. Previous experience with advanced reactor and fuel cycle development has identified sound concepts for addressing concerns over economics, waste management, safety and proliferation. The challenge is to improve these concepts and incorporate them all into a system that is sufficiently attractive, that it will be selected for deployment over less-desirable options.
4. Conclusion We can all be thankful for nuclear power, for it may well be essential to the long-term survival of civilization. Within the seeds of its potential for great good, are also the seeds for great harm. We must ensure that it is applied for great good. What is not in question is whether we can live without it, we cannot. United States leadership is crucial in determining how this technology is developed and applied. The size and capability of the United States’ technical community is decreasing, a trend that cannot be allowed to continue. It is my belief that in the future, the need, the vision and the confidence in nuclear power will be restored, but only if we address the immediate challenges before us. It is a national challenge worthy of the best people this nation has to offer.
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References w1x J.M. Holl, Argonne National Laboratory, 1946–96. University of Illinois Press, 1997. w2x M. Damian, Atoms in flux. Forum for Applied Research and Public Policy, Executive Sciences Institute, Davenport, IA, Spring 1996, p. 88. w3x Nuclear Energy Institute, Meeting Our Clean-Air Needs with Emission-Free Generation, May, 1999. w4x Nuclear Energy Institute, Nuclear Power Plant Performance, September, 1999. w5x Nucleonics Week, 40, Ž27. Ž1999. July 8. w6x British Petroleum Company PLC, BP Statistical Review of World Energy. Brittanic House, London, 1998. w7x The experimental breeder reactor-II inherent safety demonstration, in: S.H. Fistedis ŽEd.., Nuclear Engineering and Design, vol. 101 Ž1. Ž1987.. w8x The technology of the integral fast reactor and its associated fuel cycle, in: W.H. Hannum ŽEd.., Progress in Nuclear Energy, vol. 31 Ž1r2. Ž1997..