Statement of Ronald C. Davidson U.S. House of Representatives Madame Chairman, Members of the Committee thank you for the opportunity to testify before this Committee on behalf of the Princeton Plasma Physics Laboratory and in favor of a revitalized national effort to develop fusion energy. I would also like to thank you for your sustained support for the development of magnetic fusion as one of our nation's long-term energy sources. Role of Fusion Energy Energy is the lifeblood of our nation's economic and energy security. For this reason, the United States must develop adequate domestic sources of energy. In the short term, energy conservation and increased efficiency are needed, while a secure, environmentally safe energy source is developed for the longer term. Fusion is such an energy source, with a plentiful fuel supply available from the deuterium in ordinary water. Fusion has the potential to satisfy the world energy needs for many centuries without producing acid rain or global warming gases. Fusion will produce very low radioactive waste, and will use materials unsuitable for proliferation of nuclear weapons. The goal of the Department of Energy's magnetic fusion energy program is to build an attractive fusion demonstration reactor in the 2025 time frame, thereby allowing fusion to be developed as a commercial energy source around 2040. Fusion could be developed on a faster time scale if a stronger national commitment were made. Providing secure, safe energy for the future of the world's growing and developing population is one of the great challenges facing humankind. I have no provide that required energy. What was once thought impossible is now generally accepted, and the debate has turned to the questions: When will we get there and can we afford it? Harnessing the energy process of the stars is a major scientific and technological challenge, but we know the steps required to achieve practical fusion power production, and significant technical progress has been made towards this goal. During the past decade, the rate of progress in fusion could have been greater. The rate of progress has been determined, not by technical impediments, but by the level of effort and national commitment. The need for new electric power plants is apparent. By the middle of the next century, the world will spend tens of trillions of dollars on electricgenerating capacity to replace existing plants and to meet the demands of a growing population. I believe that a significant fraction of that capacity should be provided by fusion plants, rather than the technologies of today that threaten our air, our climate, and even our safety. I also believe that those plants should display labels reading "Made in the USA." Technical Status In the 1970s, the United States, Europe, Japan and the Soviet Union made significant investments in the development of magnetic fusion. What has been accomplished with these investments? Let us compare fusion progress with that in computer memory chips. One of the great scientific achievements of the past twenty years has been the fabrication of computer memory chips, which has increased from 120 characters per chip in 1970 to 2,000,000 characters per chip in 1992 an increase of twenty thousand. During the same period, magnetic fusion experiments have demonstrated fusion reactions increasing from onehundredth of a watt in 1970, to 1,700,000 watts achieved on the Joint European Torus (JET) in 1991 an increase of one hundred million! When the construction of the Tokamak Fusion Test Reactor (TFTR) began at Princeton in 1976, one goal was to produce fusion plasma temperatures of one hundred million degrees Celsius as required in a fusion reactor. TFTR easily surpassed this goal, producing temperatures of four hundred million degrees Celsius, and has been the world leader in producing, optimizing and investigating such high-temperature plasmas. The TFTR experiments, using deuterium (an isotope of hydrogen) as a "low octane" fusion fuel to optimize plasma conditions, have produced world-record fusion power for this fuel. This fall, TFTR is expected to produce about five million watts of fusion power in experiments using tritium, a "high octane" fusion fuel, mixed with deuterium, which will be the fuel mixture used in a fusion reactor. This power level is three times the power produced in Europe's largest experiment, JET, which is five times larger in volume than TFTR. In 1994, TFTR expects to increase the power level to about ten million watts, which would satisfy the TFTR design goal established in 1975 for the production of one-to-ten million watt-seconds of fusion energy. A key remaining scientific issue in magnetic fusion is associated with the self-heating of the plasma by the fusion reaction products called alpha particles, thereby allowing the fusion reaction to be self-sustaining. Far beyond the original goals of TFTR, scientists now project that the initial indications of selfheating of a plasma by alpha particles are likely to be detected for the first time in TFTR. While the TFTR experiments have taken longer than originally projected because of funding limitations, more has been accomplished than was planned, and the funds required to complete the TFTR program will be $250 million less than estimated in the early 1980s. Similarly, the world-wide fusion program has made significant advances in the science and technology goals set forth in the mid-1970s. The time has come to move forward with a new generation of fusion devices to address the technical issues remaining to develop magnetic fusion as a practical energy source. Near-Term Requirements The critical tasks required to achieve the goal of a practical fusion demonstration reactor are: • Determination of deuterium-tritium plasma confinement and alpha-particle heating on the Tokamak Fusion Test Reactor (TFTR), followed by demonstration of a self-heated reactor-grade plasma and associated nuclear technologies on the International Thermonuclear Experimental Reactor (ITER); Development of the advanced, steady-state Tokamak Physics Experiment (TPX), a national facility to improve the tokamak concept, leading to a more compact and economical fusion demonstration reactor; and Development of low-activation neutron-resistant materials for the reactor structure. The solutions to these technical tasks are pursued most effectively on parallel paths in a collaborative world fusion program. The highest priority in the U.S. fusion program is to carry out expeditiously the TFTR program and extract the maximum information on deuterium-tritium plasmas, alpha-particle heating and tritium-handling technology. While technical surprises are not anticipated, confirmation of the expected deuterium-tritium results in TFTR is needed in order to proceed with the construction of the International Thermonuclear Experimental Reactor (ITER). The U.S. should be a leading partner in ITER, an engineering test reactor to demonstrate the scientific and technological feasibility of magnetic fusion energy, which has been identified as a required step in the development of fusion for more than a decade. The ITER Engineering Design Activities (EDA) is an international collaboration among the United States, Europe, Japan and the Russian Federation. ITER is being conservatively designed to operate reliably on the basis of today's scientific knowledge and is expected to produce one billion watts of fusion power for a duration of about fifteen minutes. In many aspects, ITER will be a reactor prototype that would satisfy the Energy Policy Act of 1992 goal of a technology demonstration that would verify the technical feasibility of fusion power production at the levels required in a commercial power plant. ITER is a very important step in the international quest to develop fusion energy and merits strong support by the United States' Congress, including the identification of a candidate U.S. site suitable for ITER and a fusion demonstration reactor. The Energy Policy Act of 1992 also calls for the design and construction of a major new national facility for fusion research and technology development consistent with U.S. participation in ITER and industrial participation in the development of the technologies required for fusion. The Tokamak Physics Experiment (TPX) has been identified by U.S. fusion experts as this major new facility with the goal to improve the performance and effectiveness of the tokamak reactor concept. TPX will be a unique facility worldwide and will develop improvements leading to new operating modes for ITER, testing of divertor concepts and high-heat-flux components, and allowing ITER to carry out more effectively its technology testing phase. Very importantly, successful results on TPX will lead to a smaller, more economical fusion reactor that would operate continuously, similar to existing power plants. TPX will be the first tokamak with the capability to operate continuously with fully superconducting magnets in the elongated divertor geometry planned for ITER and the fusion demonstration reactor. TPX construction will also play the very important role of placing U.S. industry in a strong position to compete internationally for major ITER tasks and subsystems. TPX has been organized as a national activity and is designed to follow TFTR, taking advantage of existing hardware and facilities at the Princeton site. I am pleased to report that the national TPX team, comprised of scientists and engineers from more than seventeen universities, laboratories and industries, has recently completed the conceptual design of TPX, and this design underwent a highly successful Conceptual Design Review (CDR) by an international committee of experts who urge proceeding expeditiously with detailed design and construction of TPX. On behalf of the national TPX team, I request this Committee's strong support for design and construction of TPX starting in FY94, an essential step to maintain a vigorous U.S. fusion effort, to provide for strong U.S. participation in ITER, and to lead to a more compact, economical fusion demonstration reactor. The design and construction of TPX and ITER benefit significantly from the results of existing tokamak experiments, such as the DIII-D device at General Atomics, PBX-M at the Princeton Plasma Physics Laboratory, and Alcator C-Mod at the Massachusetts Institute of Technology. These devices are testing concepts that improve tokamak performance at short pulse lengths or develop advanced divertor configurations that withstand high heat fluxes. I urge strong support for operation of these facilities and for upgrades of the DIII-D tokamak at General Atomics. |