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IB91039: Magnetic Fusion: The DOE Fusion Energy Sciences Program Richard E. Rowberg April 11, 2001 CONTENTS
For over 45 years, the United States has been trying to tame the energy source of the hydrogen bomb to produce electricity. Harnessing fusion, the nuclear reaction that powers the sun, requires confining and heating deuterium and tritium nuclei so that they will produce sustained, controlled nuclear energy. One path, called magnetic fusion energy (MFE), is to use very strong magnetic fields to confine a deuterium and tritium plasma while heating it to fusion temperatures. The potential benefits from fusion are high. The fuel resources are vast. Radioactive waste would be generated, but the long-term buildup would be orders of magnitude less than that of a comparable fission reactor. There have been several experimental fusion devices, the most successful of which is known as the Tokamak (a Russian acronym). Experiments on one in Europe, called JET, and on the U.S. tokamak called TFTR, now shutdown, have produced substantial amounts of fusion power using deuterium and tritium. The next major milestone is to operate at a level where more fusion power is produced than used heating the plasma, and to develop the technology for a fusion power reactor. A conceptual design for such a device, called the International Thermonuclear Experimental Reactor (ITER), was completed by a consortium of the United States, the European Union, Japan, and Russia. While the United States no longer participates in the ITER project, the other partners are considering a construction decision. For FY1999, both the House and Senate directed DOE to undertake a thorough review of all its fusion research activities. A 3-pronged effort to carry out those reviews has been completed, and final reports from the three efforts have been released. These reviews arrived at a number of common themes: substantial progress in the fusion science has been made and the scientific demonstration of fusion can be accomplished; there should be greater convergence of the magnetic and inertial fusion energy research programs; the United States must step-up its participation in the international fusion research effort; the budget for fusion research needs to grow if a proper balance between inertial and magnetic fusion is to be achieved; and more emphasis is needed on the broader applications of plasma science and technology. For FY2001, $248.49 million was appropriated. For FY2002, DOE is requesting the same amount of funding. No major initiatives are planned for the coming fiscal year and the level of effort for all of the activities within the program is expected to stay close to the level for FY2001. On April 9, 2001, the Department of Energy released its FY2002 budget request for fusion energy sciences (FES). DOE is requesting $248.49 million for the program, the same as that approved for FY2001. The FES programs intend to continue work on its major facilities and alternative concepts at about this year's level. In addition, funding for theoretical and basic plasma science research is expected to remain at about the FY2001 level. The program expects to complete the decontamination and decommission of the tokamak fusion test reactor facility in FY2002. Fusion (http://wwwofe.er.doe.gov/) is the fundamental mechanism in the universe for producing energy. It is the nuclear reaction that powers the stars. It is also a major contributor to the explosive power in the hydrogen bomb. Controlling this energy source to produce electricity has been sought since before the first hydrogen bomb was exploded. The potential benefits of controlled fusion are great. Successful development of a fusion power plant, however, is proving to be one of the most difficult scientific and technological challenges. Although progress has been steady, it may be at least 35 to 50 years before an operating power plant is built. Fusion is one of a class of nuclear reactions. Another is fission, which involves the splitting of large nuclei, such as uranium, into smaller elements. Fission is the energy source of the atomic bomb, the first nuclear weapon built, and of nuclear power plants currently operating. Fusion occurs when the nuclei (or core) of light atoms, such as isotopes (or forms) of the element hydrogen (deuterium and tritium), collide with sufficient energy to overcome the natural repulsive forces that exist between such nuclei. When this collision takes place, a D-T reaction is said to have occurred. If the two nuclei fuse, a heavier element, a form of helium, is created, along with a large quantity of energy. For the fusion reaction to take place, the nuclei must be heated to a very high temperature. In a hydrogen bomb, this is done by exploding a fission bomb, uranium or plutonium, forcing the deuterium and tritium together in a violent manner. Fusion reactions are possible between a number of light atoms, including deuterium alone (a D-D reaction); deuterium and helium-3, an isotope of the element helium (a D-3He reaction); and hydrogen and the element lithium, a light metal. All of these reactions occur much less frequently at a given temperature than the D-T reaction. For instance, the fusion energy produced from D-T reactions in a mixture of deuterium and tritium will be about 300 times greater than that from D-D reactions in a mixture of deuterium alone if both mixtures are heated to the same temperature and have the same density. For this reason, research into controlled fusion has concentrated on developing deuterium-tritium fueled reactors. Potential Benefits of Magnetic Fusion Energy The potential benefits of controlled fusion are many. Foremost is that in principle the fuel for such a plant is essentially inexhaustible. One out of every 6,670 water molecules contains deuterium rather than hydrogen, and there are no significant technical barriers to extracting deuterium from water. Tritium, however, does not occur in nature. It can be produced from the element lithium, which is also very abundant, although much less so than deuterium. To achieve the full resource potential of fusion will require reaching the conditions of plasma density, temperature and confinement time needed for energy production from reactions involving deuterium alone. As described below, these conditions are much more harder to reach than for deuterium and tritium which has proved difficult enough. Fusion researchers, however, note that even if success is reached with the D-T reaction, research will need to continue to reach power production from the D-D reaction. Environmental and Safety Considerations There also could be important environmental benefits from fusion. First, a controlled fusion power plant would be inherently safe. A reaction that became "uncontrolled" in such a plant would extinguish itself almost instantly with no part of the system melting and with no significant release of radioactive material. Even major accidents that could occur, such as to the structure of a fusion powerplant would not result in any radiation release. Of course, such an accident could result in significant cost because of severe reactor damage. A second environmental benefit is that the radioactive waste products produced in a fusion plant would be far less of a problem than those produced in a fission plant. Because of the nature of controlled fusion, it would be possible to reduce the long-term buildup of radioactive waste products by up to a million times below that of a fission system of comparable size while the quantity of radioactive material produced in a power plant of a given size may be comparable for the two types of reactions (at least for the first generation, deuterium-tritium fusion plants), the half-life of the radioactive products from such a fusion plant would be on the order of 100 years or less, compared to tens of thousands of years for those from a fission plant. Radioactive products from fusion plants, therefore, would decay much faster than those from fission plants, resulting in the large differences cited above. More advanced fusion systems using fuel combinations which produce few or no neutrons, such as the D-3He reaction, would result in substantially less radioactive waste. Paths to Fusion Energy Production Two paths are being taken in attempts to attain controlled fusion. The first is to confine the light nuclei by a magnetic field and to heat them with an external source of electromagnetic energy. In this case, the deuterium and tritium are in a gas-like condition called a plasma. This process is called magnetic fusion energy (MFE). The other path is to heat very small clusters of solid deuterium and tritium by compressing these clusters with lasers or beams of particles. Such a process is called inertial confinement fusion (ICF) and simulates -- on a very small scale -- the actions of a hydrogen bomb. Once the reaction starts in either case, it is possible in principle for the heat generated by the fusion reactions to be sufficient to cause other light nuclei to collide, thereby sustaining the reaction without an external energy source. Such a condition, called ignition, has not yet been reached in practice. While substantial progress has been made over the last several years in both ICF and MFE, even the less stringent condition of break-even -- the point where power produced by the fusion reactions equals the power supplied by the external energy source -- is still to be achieved. A fusion power plant would operate between break-even and ignition. The ratio of power out to heating power supplied would be significantly greater than for break-even, but external energy would still be supplied to control the reaction rate. By way of comparison, stars operate by using their enormous gravitational force to confine the colliding nuclei. Enough heat is generated by the fusion reactions to force other nuclei to collide and undergo fusion so the reaction is sustained. Because of the large gravitational forces, these nuclei are unable to escape the stellar region before they gain the necessary energy to fuse with one another. Achieving break-even and power amplification would be only the first steps in the process of producing useful power. The energy from the nuclear reactions would have to be converted into another form that could be used to do work. Energy is carried away from the fusion reactions in the form of neutrons moving at high speed. Because neutrons do not have an electrical charge, they are not confined by the magnetic field and will leave the plasma region. The neutrons will give their energy up if they collide with atoms of another material, causing that substance to heat. A prime candidate for this material for future fusion power plants is the liquid metal lithium. Lithium that is heated by colliding neutrons could then transfer that heat to water, producing steam. The steam, in turn, would drive a steam turbine and generator, producing electricity. While there are no fundamental scientific barriers to this process, putting it into practice will be a complicated engineering task requiring substantial development. A second reason for using lithium is that reaction between the lithium atoms and the neutrons would produce the tritium necessary for the reactor fuel. Magnetic Fusion Energy Research Both the magnetic fusion energy (MFE) and inertial confinement fusion (ICF) research activities are funded by the U.S. Department of Energy (http://www.doe.gov). The ICF program currently is primarily oriented to defense applications, for simulation of nuclear weapons, although energy applications are an important part of the research effort. Nearly all of the funds for ICF research come from DOE's Defense Programs (http://www.dp.doe.gov). An major initiative of the DOE ICF program is the National Ignition Facility (NIF) (http://www-lasers.llnl.gov/lasers/nif.html) at DOE's Lawrence Livermore National Laboratory which is currently entering the detailed engineering design stage. The NIF is primarily for weapons applications, but it will also carry out important research for potential energy production from inertial fusion. Magnetic fusion energy research is within DOE's civilian programs and is located in the Office of Energy Research. Although funding for ICF research now exceeds that for magnetic fusion, the latter has been and continues to be the major fusion energy focus in the United States. Magnetic fusion energy research has been underway for nearly 50 years. The scientific challenges are to develop ways to confine a high-density deuterium and tritium plasma and to heat it so that the combination of temperature, density, and confinement time are sufficient that break-even and beyond are reached. Considerable progress has been made in the last 20 years in meeting these scientific challenges. Since the mid-1970s, the amount of measurable fusion power produced in fusion experiments has increased by a factor of nearly 100 million, or eight orders of magnitude. Much of the progress towards achieving those goals has taken place on toroidal (donut-shaped) concepts. The most successful such concept has been the tokamak (a Russian acronym), first demonstrated in the former Soviet Union in 1968. It is a device in which the plasma is contained in a toroidal chamber surrounded by magnetic field coils. The plasma produces a large electric current by circulating within the chamber, and the combination of the magnetic field produced by that current and by the coils imparts a high degree of stability to the plasma. This stability has made possible much longer confinement times than previous devices. Currently, the largest and most successful tokamak still operating is the Joint European Torus (JET) (http://www.jet.uk) which is located in Great Britain and is funded by the European Union. The tokamak fusion test reactor (TFTR) at Princeton Plasma Physics Laboratory (http://www.pppl.gov), which was one of the largest, was shutdown in 1998 because of reductions in the U.S. fusion research budget. Other large tokamaks are operating in Japan, Italy and France, and in San Diego (http://fusioned.gat.com) and at MIT. In September 1994, the TFTR produced 10.7 MW of fusion power using a mixture of deuterium and tritium (D-T) to form the plasma. A ratio of power produced to power used to heat the plasma, called Q, of about 0.3 was reached. In 1997, JET reached an output of nearly 16 MW under the same conditions. In addition, JET results indicate that alpha particles formed by the fusion reaction are providing about 10% of the plasma heating. In TFTR, there was evidence of enhanced confinement of the plasma during the heating pulse and some indications of heating of the plasma by alpha particles. It appears that plasma behavior is improved by the addition of tritium. Many in the fusion research community believe these experiments demonstrate conclusively the scientific feasibility of controlled fusion. In Japan, a large tokamak called the JT-60U (http://www-jt60.naka.jaeri.go.jp), recently reported reaching conditions in a deuterium only plasma which would be equivalent to break-even conditions, Q=1.05, in a plasma of 50% tritium and 50% deuterium. A value of 20,000 kW is expected to be reached on JET within the next few years. The design power output of the International Thermonuclear Experimental Reactor (ITER), as presented in the final report of the project's Engineering Design Activity (EDA) is 1,500,000 kW (http://www.iter.org). In developments that offer great promise for an eventual fusion power reactor, researchers at Princeton, before the TFTR was shutdown, and at General Atomics in San Diego (on its DIII-D tokamak) have been able to greatly enhance plasma confinement in their tokamak devices. In addition, the loss of heat from the plasma has been reduced by over a factor of 40 and the peak density of the plasma increased over three times. The process used has been explored in the past, but only to a limited extent. These new experiments expanded the region in the plasma over which the process was in effect. Scientists at Princeton were also able to perform experiments on the TFTR prior to its shutdown that demonstrated promising new operating regimes for a tokamak plasma. A preliminary prediction by some fusion researchers is that these developments could reduce the size and cost of an eventual fusion reactor based on the tokamak concept by about 50%. Most recently, researchers at General Atomics have reached plasma densities that exceed the limits previously thought possible given the parameters of the DIII-D facility. Because the power output increases as the square of the density (a doubling of density would increase power output by a factor of four), these results portend the possibility of more power from a given size fusion power plant or a smaller power plant to achieve a given power level. The ultimate goal of the worldwide effort in controlled fusion research is to develop useful energy -- most likely electricity -- from a fusion powered reactor. In the central attempt to reach this goal, the major players in the international fusion research effort-- the United States, Japan, Russia, and the European Union -- participated in the engineering design of the largest international science project to date, the International Thermonuclear Experimental Reactor (ITER). The project's ultimate objective was to demonstrate extended operation of a fusion plasma after substantial power amplification has been achieved. It also would have served as an engineering test bed for those systems needed on an operating power plant. The first phase of this project, completed in December 1990, yielded a conceptual design of a reactor. The next phase was the development of a detailed engineering design, called the Engineering Design Activity (EDA), which began in 1992 and was completed in July 1998. The cost of the EDA was about $1 billion. A decision on whether to build the machine was to be made upon completion of the EDA. The ITER Council, however, proposed a 3-year extension to the agreement. This extension was signed by Japan, the European Union, and Russia, in July 1998. The United States, reacting to concerns by Congress, did not sign the extension. On September 29-30, 1998, however, the DOE announced that the United States signed a one-year extension to complete the EDA work. The DOE announcement stated that its action had come after consultations with the chairman of the House Appropriations Subcommittee on Energy and Water Development. During the extension period, alternatives to the ITER design, including a reduced-cost option, have been considered, and discussions of whether to proceed with construction of some form of ITER has taken place. In October 2000, a revised design of ITER was announced (see below) although no construction decision has been announced. Currently the international fusion community is considering options for the next step in the development of fusion energy. Most believe that construction of a burning plasma device -- one that produces more fusion energy than is needed to heat the plasma -- is essential. Many in Europe and Japan hope that the revised ITER will be that device. Others believe that a decision on a burning plasma experiment should wait for more results on the large facilities currently operating in Europe and Japan, including two large stellarators, and on the advanced tokamaks. On October 5, 2000, the Director of the DOE Office of Science asked the FESAC to address key scientific issues about a burning plasma physics experiment. The report is to be delivered by July 2001. Whatever the decision, it would likely be followed by a facility capable of producing small amounts of electric power. Finally, a demonstration fusion power reactor would be built that would verify the economics and reliability of an operating power plant. Currently, some fusion researchers speculate that such a demonstration plant could be operating by 2050. Department of Energy Research Program The nation's magnetic fusion energy (MFE) research program began in 1951 under the auspices of the former United States Atomic Energy Commission. Since that time, the United States has spent over $16.6 billion, in constant 2000 dollars, on research into MFE. Figure 3 (next page) shows the budget history since 1954 in constant 1994 dollars. The MFE appropriations for FY2000 and FY2001, and the FY2002 request are shown in Table 1. These amounts will be discussed in more detail below. The breakdown according to activities is shown in the table. Under science, DOE funds research into the tokamak and alternate confinement concepts, plasma theory, and general plasma science. Within this activity, DOE is funding research on two large tokamak efforts, the DIII-D at General Atomics in San Diego, and the Alcator C-Mod at the Massachusetts of Technology, and the National Spherical Tokamak Experiment (NSTX). Under facilities operations, DOE funds operations and maintenance for the two major tokamak facilities and the NSTX, and decommission of the TFTR. Funding within enabling R&D is directed at basic research in fusion technology and the development of technologies needed to facilitate plasma science research and ultimate development of a fusion energy source. Budget. On October 18, 2000, Congress completed work on the Energy and Water Development Appropriation Bill, 2001 (H.R. 5483, H.Rept. 106-988), and it was signed into law (P.L. 106-377) on October 27, 2000. A total of $255 million is provided for the FES program. After accounting for a general reduction and other adjustments, the final total for FY2001 is $248.49 million. An additional $25 million for high average power laser development was approved in the DOE defense programs account. For FY2001, funding for the major experimental activities under science is slightly above the FY2000 levels. Tokamak research is focusing on advanced tokamak concepts in the DIII-D device, confinement and heating of ignition plasmas in the Alcator C-MOD, and the startup of operations of the Electric Tokamak at UCLA. Under alternative concepts, work is continuing on exploring properties of the spherical tokamak concept on the NSTX, on a proof-of-principle experiment for the compact stellarator, and on concept evaluation experiments for 12 other concepts. In addition, the program's inertial fusion energy (IFE) research efforts are planning to continue a focus on scientific issues associated with heavy-ion accelerators as a possible IFE driver. Funding for theory and general plasma science is also somewhat higher for FY2001 than for FY2000. The increase in the theory is being directed at advanced computational simulation and modeling. Under facility operations, funding should support 17 weeks of operation on the DIII-D facility, 14 weeks on the Alcator C-MOD, and 17 weeks on the NSTX. Installation of a new plasma heating system on the DIII-D is expected to be completed in FY2001. A slight increase in funding was approved for enabling R&D for FY2001. Under engineering research, a focus on supporting existing U.S. fusion research facilities is underway along with the development of a Virtual Laboratory for Technology to manage research on the wide array of fusion technologies. Materials research priorities include advanced materials evaluation and modeling. A total of $19.1 million ($13.3 million for FY2000) was approved for continued decommissioning and decontamination of the TFTR, and $3.2 million (none for FY2000) for waste management at the Princeton Plasma Physics Lab. As a result of these last two items, total funds available for research and facility operations for FY2001 are $225.2 million compared to $225.7 million in FY2000. For FY2002, DOE is requesting the same amount as approved for FY2001, $248.49 million. The budget justification published by DOE shows a request of $238.49 million, but it notes that an additional $10 million will be sent to Congress in a forthcoming budget amendment. Details about how the additional funds are to be allocated have not yet been provided and are not shown in the table above. Funding for science category is currently scheduled to decline by 2.1% from the FY2001 level. Programs in this category include tokamak experimental research, alternative concept experimental research, theory, and general plasma science. Funding for facility operations is currently scheduled to decline by 7.6% from the FY2001 level. Programs within this category include TFTR decontamination and decommissioning (D&D), and operations and maintenance for the DIII-D, Alcator C-Mod, and NSTX facilities. Funding for enabling technologies is now scheduled to decline by 1.0% from the comparable FY2001 level. Programs within this category include engineering research and materials research. The FY2002 funding request levels for these categories and the individual programs are likely to change once the $10 million budget amendment is allocated. Within the science category for FY2002, tokamak-related efforts will focus on increasing plasma heating and stability on the DIII-D device, on exploration of advanced confinement modes in Alcator C-Mod, and on understanding other plasma phenomena in the tokamaks at UCLA and Columbia University. Collaborative research on several large foreign tokamaks is planned for FY2002 focusing on important magnetic fusion energy issues. Under alternative concepts, efforts on the NSTX will focus on increasing plasma current and demonstrating new concepts for initiating and maintaining that current, and on the study of intense heavy ion source drivers and technical assessment of IFE concepts. In addition, funding is planned for 12 small alternative concept experiments, one proof-of-principle experiment, and a design for a compact stellarator proof-of-principle experiment. Theoretical research for FY2002 will continue to focus on the application of advanced computing to solve complex plasma and fusion science problems. The general plasma science program plans to continue funding peer reviewed proposals addressing basic plasma physics and engineering research. Within the facility operations category, funding for FY2002 is planned for completion of the decommissioning and decontamination of the TFTR. In addition, funds are to be provided for operation and maintenance of the DIII-D, C-Mod, and NSTX facilities. The latter is expected to include upgrades to the diagnostics. Funds for 14 weeks of operation of the DIII-D, 8 weeks for the C-Mod, and 11 weeks of the NSTX are included in this portion of the request. In the enabling R&D category, funding for FY2002 is planned for plasma technology development critical for domestic experiments including high power microwave generators and plasma-facing technologies; for technical assessment of critical IFE technologies; and for design studies of the next steps in fusion experiments for achieving fusion energy production. In addition, funding in this category is planned for continued experimental and modeling research on the behavior of materials properties when subjected to fusion plasma particle and heat fluxes. In related activities, 150 fusion researchers, in a statement issued in February 2001, urged Vice President Cheney in his role as director of a task force to develop the Administration's energy policy proposal, to consider an accelerated research effort to develop fusion energy as a long-term energy option. Also, FESAC is currently preparing a report at the request of the Director of the DOE Office of Science that considers a number of issues including the ability of the FES program to meet its five-year goals. A draft of that report suggests that insufficient funding is hindering the program's ability to maintain an adequate rate of technological advance towards fusion energy development. FESAC argues that program goals were predicated on annual appropriations of about $300 million, which has not been met any year since the goals were set. In particular, operating time on the program's major user facilities has been insufficient and decisions about the development of new facilities are being delayed. Program Reviews. Primarily as a result of congressional direction, DOE set in motion three major reviews of its fusion research activities from 1998 to early 1999. One was carried out by FESAC and consisted of two parts. The first summarized "the opportunities and requirements of a fusion energy science program" while the second provided recommendations for proof-of-principle experiments and program balance between tokamak and alternative options, and between inertial and magnetic fusion. The second review -- of the magnetic (MFE) and inertial confinement energy (ICF) programs -- was done by a task force on fusion energy of the Secretary of Energy Advisory Board (SEAB) (see below). That review was in response to the Senate Appropriations Committee in its report accompanying its version of the FY1999 DOE appropriations bill. The task force met four times: March 29-30 in Washington, DC, 29-30 April at the Princeton Plasma Physics Lab, May 26-27 at Lawrence Livermore National Lab, and July 9 in Washington, DC. The third review was carried out by the National Research Council (NRC) to assess the scientific quality of the fusion energy science program. The NRC issued its final report (see below) on October 23, 2000. A major motivation for these studies was for DOE to reexamine how it approaches fusion research by considering all of the options its supports in a comprehensive manner. In addition to the three reviews, a two-week summer workshop on MFE and ICF was held at Snowmass, CO in July, 1999, with the findings of that workshop reported to FESAC for consideration during its program review. Restructuring. The magnetic fusion program is now entering a second phase of its restructuring, which began in 1996. The first phase resulted in a significant shift in program focus from primarily being concerned about fusion energy technology development to one concentrating on plasma and fusion science and technology research. This second phase has been brought about by the ending of U.S. participation in the ITER project and a congressional mandate to review the entire DOE fusion effort including both its IFE and MFE programs. Formal participation in the ITER project by the United States ended in FY1999. The other partners are continuing with the program, however, and currently are reviewing options for the next step in the project. In October 2000, the outline of the new ITER design was announced. The revised design is for a machine significantly smaller than the one that emerged from the Engineering Design Activity that was completed in July 1998. A that time, the partners decided not to proceed with construction because of financial constraints including the U.S. withdrawal from the program. The revised design would cost about 50% of the July 1998 model and would aim at producing a Q of about 5 or greater during steady-state operation and 10 for pulsed operation. While ignition would not be a primary goal of the new design, called ITER-FEAT, it would not be precluded. At this time, however, a decision on whether to proceed with construction is still pending. With the end of the ITER project, Congress directed DOE to reconsider its entire fusion effort in an attempt to bring about more of a convergence between the MFE and inertial confinement fusion programs funded by the agency. While recognizing the need to maintain a strong defense focus for the ICF program, Congress nevertheless expressed its view that more could be done to join the energy aspects of the ICF program with the MFE research effort. The result of this congressional direction was a series of studies -- listed above -- carried out over the last several months exploring ways to bring about this convergence. All of these studies are now complete, and each involved researchers from both the IFE and MFE fields. SEAB Fusion Task Force. The Task Force found that progress in fusion science has been substantial and that the basic scientific feasibility of fusion can be demonstrated http://fire.pppl.gov/SEAB_final_Aug99.pdf. The Task Force also endorsed the broader focus of the MFE program on fusion and plasma science and engineering with greater attention to alternate confinement concepts. Because of the large international and DOE Defense Program (in ICF) efforts, however, the Task Force argued that the Office of Fusion Energy Science (OFES), by itself, is not able to define the direction of the total fusion research effort. To leverage those external efforts more effectively, the Task Force believes that current funding for the OFES is "subcritical," and that more funds are needed - perhaps $300 million per year - if the program is to become more balanced in terms of developing a source of energy. The Task Force also recommended "stable and meaningful" participation in international fusion research, particularly in view of the large cost requirements of future burning plasma experiments including, possibly, ITER. In this connection, early discussions with Congress were deemed important so that any participation could coexist with the current broad-based domestic program. The Task Force noted that any new large international project will require clear understanding of its goals and broad political support. FESAC Report on Priorities and Balance. The FESAC panel endorsed the findings and recommendations of the SEAB Task Force. In addition, the panel considers the current MFE program to be reasonably well in balance but did urge more emphasis on pulsed concepts http://fire.pppl.gov/FESAC_Priorities_Final99.pdf. It noted that restructuring was not yet complete and the program could be strengthened with "moderate" budget growth. The panel recommended four areas as targets for any budget increases:
The panel noted that both IFE and MFE have a fusion energy goal and a strong science focus, and would benefit from greater interaction among researchers and research facilities. The Panel recommended that both IFE and MFE concepts be given equal weight in the developmental process leading up to a possible fusion energy source - concept evaluation (CE), proof-of-principle (PoP), and performance extension. Further, a common peer review process should be established. The Panel recommended six guiding principles for achieving better MFE/IFE balance:
The Panel noted that the OFES IFE program can focus on driver development because the DOE Defense Programs (DP) is concentrating on target physics. The Panel recommended that the OFES IFE program develop the driver knowledge base that would be needed for an integrated research experiment (IRE) using target physics obtained from DP research. The Panel made several recommendations for specific objectives for that knowledge base for an IRE-scale driver, and other objectives for longer term development of an engineering test facility. The Panel concluded with recommendations on spending various budget increments to the MFE program for IFE activities. In all cases, the heavy ion beam option was given priority, with greater funding for the laser drivers and exploratory concepts if more than $30 million were made available to the IFE activities. The panel considered two funding levels for fusion energy research above the FY1999 level -- $260 million and $300 million. In both cases, $10 million for advanced laser development within DP is included, with all other funds being assigned to the OFES. The panel provided details about where incremental funding within OFES should be directed.
Finally, the Panel noted areas of theory and technology that are cross-cutting to the two programs that could be enhanced by expanded budget resources. The theory activities should have a stronger focus and be coordinated with the concept evaluation and PoP stages. FESAC Report on Criteria, Goals, and Metrics. This report was prepared by a special panel for consideration by FESAC during preparation of its report on Priorities and Balance http://vlt.ucsd.edu/fesacmetrics.doc. The panel recommended that DOE continue with the stages of development first described by the FESAC Alternate Concept Review Panel in 1996. Progress through these stages -- concept evaluation (CE), proof-of-principle (PoP), performance extension (PE), fusion energy development, and demonstration -- would be governed by peer and expert review. A set of criteria to make the evaluation was presented by the panel. The panel also noted that the international magnetic fusion effort is about 5-6 times greater than the U.S. effort, and the U.S. should participate as appropriate in order to leverage its research program. In IFE, the U.S. is by far the leader and OFES should supplement the DP effort. The panel developed metrics for each of the nine program elements within IFE/MFE research. The panel stated that a functioning program will have many more projects under consideration at the lowest - CE - level than at the higher levels. The higher levels, however, will dominate the budget because the projects will necessarily be larger. Because of the large cost, international collaboration is essential along with collaboration with the ICF/Defense Programs research effort. A balanced program will involve projects at each stage. A balanced program will see at least one IFE and one MFE approach through all the stages. The CE projects usually require small staffs and can be sited at a number of places. The larger - PoP and above - projects should national in nature although they will require substantial local resources. NAS - Fusion Science Assessment Committee (FuSAC) Final Report. The NAS study, An Assessment of the Department of Energy's Office of Fusion Energy Sciences Program http://fire.pppl.gov/FuSAC_Prepub_Draft_Fig.pdf was carried out to examine the quality of research being supported by the OFES. The FuSAC concluded that U.S. fusion research has made significant advances over the past several years and is now in a position to make critical contributions to guide new scientific discovery in the program. The committee also concluded that the quality of magnetic fusion science is at least as good as that from other major physical science fields within the United States. At the same time, however, the Committee found that the concentration of fusion research on energy production has led to growing "intellectual" isolation between the magnetic fusion research and other scientific fields. As a result, there is insufficient appreciation by other scientists of the quality of magnetic fusion science and a stagnation of the interchange of ideas between fusion and the rest of science. This, according to the Committee, has led to a "negative view of fusion science" and a decline of new entrants into the field. The Committee stated that a more outward looking program, focusing on important scientific goals, would both alter this view and enhance progress towards practical fusion power. The Committee had several other recommendations for the U.S. fusion program. Among them are the adoption achievement of greater understanding of scientific understanding of fusion plasmas as a "central goal"; the reduction of the "scientific isolation" that now exists between fusion researchers and scientists in other fields; the introduction of new centers of fusion science research selected on an open, competitive basis; the development of strong support within the scientific community for U.S. funding of a burning plasma experiment; and the expansion of the role of the National Science Foundation in supporting plasma science research. The Committee concluded its recommendations with support for continued assessment of the prospects for achieving fusion energy, and periodic reviews of the quality of fusion science research. Snowmass Meeting. This meeting brought together IFE and MFE researchers to develop a consensus on the key science and technology issues for plasma science, technology and fusion energy development The participants also identified opportunities for existing and future facilities and programs to contribute to making fusion an attractive energy source http://www.ap.columbia.edu/fusion/snowmass/WG_Summaries.html. The workshop divided into six groups - magnetic fusion concepts, inertial fusion concepts, emerging concepts, plasma science, technology, and energy issues. A number of overlapping issues were identified for the various concepts. Discussion. Several themes emerge from these reports. First, there is general agreement that progress in fusion science has been substantial and that the basic scientific feasibility of fusion will be successful. Such an event, of course, will still leave a number of major scientific and technical issues that must be resolved before an economically attractive fusion power plant can be built. Nevertheless, it appears to be only a matter of time before the fundamental scientific issues are resolved and the participants in these studies urge continued and aggressive pursuit of that goal. Second, greater convergence between the MFE and IFE paths is possible and desirable. The consensus of the reports is that OFES should be primarily responsible for coordination of IFE and MFE research, with most of the incremental IFE work being managed by OFES. It would be necessary, however, for OFES to leverage the work of the international MFE research community and the ICF work funded in DOE Defense Programs. An important implication of this theme is that significantly greater interaction between DOE's OFES and ICR programs appears necessary. In response to this point, the OFES requested a group of fusion researchers, led by Dr. Charles Baker, to develop an integrated program plan (IPP) that incorporated both MFE and IFE. The plan was to incorporate both energy and science goals, describe the interrelationships between the two areas, set milestones, and link program goals and accomplishments. A final report was issued on November 2, 2000 http://vlt.ucsd.edu/. The report takes as its starting point the findings of the three reports discussed above along with another FESAC report, Opportunities in the Fusion Energy Science Program, published in June 1999 http://wwwofe.er.doe.gov/more_html/FESAC/Summary.pdf. The key elements of the IPP are the four MFE and two IFE program goals developed by FESAC. Theses goals are connected to fusion program activities, objectives, and milestones. To achieve these goals, the IPP study group finds that several layers of integration are required including the four MFE goals, the various IFE concepts, the MFE and IFE programs, and the U.S. and world fusion programs. The report also notes that coordination between the OFES and the National Nuclear Security Agency's ICF programs is essential. The body of the report describes in some detail a strategic framework for IFE/MFE integration, the principal scientific goals, and key research categories and their relationship to the goals. At this point, it is unclear how DOE will implement the IPP. It is likely, however, to play an important role in the convergence of the two approaches as DOE carries out the recommendations of SEAB and FESAC in response to congressional direction in this area. A third fourth theme is that strong international participation is essential. As mentioned, the international magnetic fusion research effort is about 5 to 6 times larger than the U.S. effort. Further, there are currently several large one billion dollar plus machines, at the performance extension (PE) stage, either operating or under construction in Japan and Europe in which some level of U.S. participation would be desirable. While the United States has three such PE machines -- the Alcator C-MOD, DIII-D, and NIF -- it is unlikely that any additional fusion machines of that size will be constructed in the United States in the foreseeable future. Therefore, construction of additional PE-size and fusion energy development facilities will undoubtedly require an international effort. Fourth, the reviews strongly urged a budget increase for OFES to about $300 million per year for the next 5 years. The balance between MFE and IFE research recommended in the reviews would not be possible at current budget levels. It was noted at the time that a funding level of $250 million for OFES and an additional $10 million for laser development within the ICF program (amounts approved for FY2000), would go a long way toward achieving a more desirable balance if most of the increment for OFES went to IFE research. For FY2001, $252.4 million was appropriated for OFES and an additional $25 million was approved for high average power laser development in the ICF program. A fifth theme was that more emphasis should be placed on general plasma science and technology research for applications beyond fusion. Several examples were given of such applications in microelectronics, lasers, environmental control, and other areas. In addition, the relation between plasma science and astrophysics, space physics, and materials science was noted. In all cases, the contribution of the plasma science developed in the pursuit of fusion was considered substantial to the entire U.S. science and technology base. In this context, a greater emphasis on plasma science research was considered very important for the program to enhance both the scientific interchange between fusion researchers and the rest of the scientific community and the development of fusion energy. The reviews appear to go a long way in providing the basis for next step in the restructuring of the DOE fusion program. The convergence of the MFE and IFE research efforts along with continued emphasis on plasma and fusion science and technology recommended by the reviewers would make DOE fusion research more comprehensive. The knowledge base needed to make a decision about the next step would also be strengthened. Nevertheless, that decision is still likely to be quite difficult. P.L. 106-60 (H.R. 2605/S. 1186) P.L. 106-377 (H.R. 5483 (4755))
Congressional Research Service. Congress and the Fusion Energy Sciences Program: A Historical Analysis, by Richard Rowberg. CRS Report RL30417 (pdf). January 31, 2000. Executive Office of the President. Office of Science and Technology Policy. Federal Energy Research and Development for the Challenges of the Twenty-first Century. Report of the Energy Research and Development Panel. The President's Advisors on Science and Technology (PCAST). Washington, D.C. November 5, 1997. National Research Council. An Assessment of the Department of Energy's Office of Fusion Energy Sciences Program, National Academy Press. Washington, D.C. (in publication). U.S. Department of Energy. A Restructured Fusion Energy Sciences Program. Advisory Report Submitted to Dr. Martha A. Krebs, Director, Office of Energy Research, U.S. DOE. Fusion Energy Advisory Committee. Washington, D.C. January 27, 1996. ---- Report of FESAC Advisory Panel on U.S. participation in the ITER construction phase to Dr. Martha A. Krebs, Director, Office of Energy Research, U.S. DOE. Fusion Energy Advisory Committee. Washington, D.C. January 1998. ---- Report of the Integrated Program Planning Activities for DOE's Fusion Energy Sciences Program, November 2000. Return to CONTENTS section of this Issue Brief. |
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