Prospects for attractive fusion power systems

As one of the alternative sources of energy for the future, fusion power mu st demonstrate that it can be a safe, clean and economically attractive opt ion in a diverse and competitive energy marketplace. Conceptual power-plant design studies for both magnetic- and inertial-confinement approaches allo ws one to translate commercial requirements into design features that must be met if fusion is to play a role in the world's energy mix. As a new tech nology in the energy marketplace, fusion must have advantages to offset the inherent technical risk of a new technology in order to be accepted. Fusio n electricity should have a competitive cost and fusion power plants should achieve a high degree of availability and reliability. Realization of the full safety and environmental potential of fusion will help fusion to achie ve a large advantage over other sources of electricity. Progress in the physics of the magnetic fusion power plant, technology and design is described for tokamaks and alternative magnetic-confinement syste ms. Recent research in this area shows that potential safety and environmen tal attributes of fusion can be realized by using low-activation material a nd care in design. The projected economic prospects show that fusion will b e capital intensive and the trends are towards higher power density and hig her-performance systems in order to enhance the economic competitiveness of fusion. In addition, alternative confinement approaches may offer substant ial economic and operational benefits, although their physics basis is much less developed. Fusion power technologies are far less advanced than plasm a technologies, since the latter have evolved in conjunction with large fus ion experiments. And yet the design, material choices and performance of pl asma-facing and nuclear components are the dominant factors in arriving at an attractive power plant. Fusion power technologies are reviewed, and the R&D needed will be assessed in the context of the world's existing programm es.