ITER presents the United States and its international partners with the opportunity to explore new and exciting frontiers of plasma science while bringing the promise of fusion energy closer to reality. The ITER project has garnered the commitment and will draw on the scientific potential of seven international partners, China, the European Union, India, Japan, the Republic of Korea, Russia, and the United States, countries that represent more than half of the world's population. The success of ITER will depend on each partner's ability to fully engage itself in the scientific and technological challenges posed by advancing our understanding of fusion. In this book, the National Research Council assesses the current U.S. Department of Energy (DOE) plan for U.S. fusion community participation in ITER, evaluates the plan's elements, and recommends appropriate goals, procedures, and metrics for consideration in the future development of the plan.

ITER presents the United States and its international partners with the opportunity to explore new and exciting frontiers of plasma science while bringing the promise of fusion energy closer to reality. The ITER project has garnered the commitment and will draw on the scientific potential of seven international partners, China, the European Union, India, Japan, the Republic of Korea, Russia, and the United States, countries that represent more than half of the world's population. The success of ITER will depend on each partner's ability to fully engage itself in the scientific and technological challenges posed by advancing our understanding of fusion. In this book, the National Research Council assesses the current U.S. Department of Energy (DOE) plan for U.S. fusion community participation in ITER, evaluates the plan's elements, and recommends appropriate goals, procedures, and metrics for consideration in the future development of the plan.

A central step in the mission of the U.S. Fusion Energy Sciences program is the creation and study of a fusion-powered "star on earth", where the same energy source that drives the sun and other stars is reproduced and controlled for sustained periods in the laboratory. This "star" is formed by an ionized gas, or plasma, heated to fusion temperatures in a magnetic confinement device known as a tokamak, which is the most advanced magnetic fusion concept. The ITER tokamak is designed to be the premier scientific tool for exploring and testing expectations for plasma behavior in the fusion burning plasma regime, wherein the fusion process itself provides the dominant heat source to sustain the plasma temperature. It will provide the scientific basis and control tools needed to move toward the fusion energy goal. The ITER project confronts the grand challenge of creating and understanding a burning plasma for the first time. The distinguishing characteristic of a burning plasma is the tight coupling between the fusion heating, the resulting energetic particles, and the confinement and stability properties of the plasma. Achieving this strongly coupled burning state requires resolving complex physics issues and integrating challenging technologies. A clear and comprehensive scientific understanding of the burning plasma state is needed to confidently extrapolate plasma behavior and related technology beyond ITER to a fusion power plant. Developing this predictive understanding is the overarching goal of the U.S. Fusion Energy Sciences program. The burning plasma research program in the U.S. is being organized to maximize the scientific benefits of U.S. participation in the international ITER experiment. It is expected that much of the research pursued on ITER will be based on the scientific merit of proposed activities, and it will be necessary to maintain strong fusion research capabilities in the U.S. to successfully contribute to the success of ITER and optimize the benefits to the U.S. from ITER participation. To that end, a U.S. Burning Plasma Organization has been formed to help focus U.S. fusion research activities needed to support burning plasma research. In addition, U.S. scientists participate in the International Tokamak Physics Activity to coordinate these activities with international partners. U.S. scientists also collaborate directly with international colleagues through several multilateral International Energy Agency implementing agreements and through U.S. bilateral agreements with the European Union and other ITER partners.

Fusion offers the prospect of virtually unlimited energy. The United States and many nations around the world have made enormous progress toward achieving fusion energy. With ITER scheduled to go online within a decade and demonstrate controlled fusion ten years later, now is the right time for the United States to develop plans to benefit from its investment in burning plasma research and take steps to develop fusion electricity for the nation's future energy needs. At the request of the Department of Energy, the National Academies of Sciences, Engineering, and Medicine organized a committee to develop a strategic plan for U.S. fusion research. The final report's two main recommendations are: (1) The United States should remain an ITER partner as the most cost-effective way to gain experience with a burning plasma at the scale of a power plant. (2) The United States should start a national program of accompanying research and technology leading to the construction of a compact pilot plant that produces electricity from fusion at the lowest possible capital cost.

In January 2003, President George W. Bush announced that the United States would begin negotiations to join the ITER project and noted that "if successful, ITER would create the first fusion device capable of producing thermal energy comparable to the output of a power plant, making commercially viable fusion power available as soon as 2050." The United States and the other ITER members are now constructing ITER with the aim to demonstrate that magnetically confined plasmas can produce more fusion power than the power needed to sustain the plasma. This is a critical step towards producing and delivering electricity from fusion energy. Since the international establishment of the ITER project, ITER's construction schedule has slipped and ITER's costs have increased significantly, leading to questions about whether the United States should continue its commitment to participate in ITER. This study will advise how to best advance the fusion energy sciences in the United States given developments in the field, the specific international investments in fusion science and technology, and the priorities for the next ten years developed by the community and the Office of Fusion Energy Sciences (FES) that were recently reported to Congress. It will address the scientific justification and needs for strengthening the foundations for realizing fusion energy given a potential choice of U.S. participation or not in the ITER project, and develops future scenarios in either case. This interim report assesses the current status of U.S. fusion research and of the importance of burning plasma research to the development of fusion energy as well as to plasma science and other science and engineering disciplines. The final report will present strategies that incorporate continued progress toward a burning plasma experiment and a focus on innovation.