Nuclear fusion: Luxurious mirage of a long-term future energy option?

The original vision of controlled thermonuclear fusion as the ideal solution of the energy problems of the mankind collides with the reality of a dramatically expensive research with too long-term, too uncertain and too limited perspectives. After more than four decades of scientific and technical research, other five decades would be required to commercialization of fusion reactors according to the constant projections the fusion community has been reiterating since the 1980s. However, alone, the huge cost/progress ratio of the attempts of the last 20 years to develop just one 'next-step' experiment and the resulting $10 billion proposal with still unresolved basic engineering/technology problems and highly uncertain physics objectives; this cannot support the anticipated rate of progress. Furthermore, due to their nuclear nature, their inherent large (GWe) size and the very complex and sophisticated technologies, fusion power plants would be strongly limited in meeting ecological, economical and political/social requirements of a future energy mix and in fitting into the already growing trend towards liberalization and restructuring of the energy market. These limitations are increasingly undermining the justification of the immense resources dedicated to research and development of fusion and its attractiveness as a virtually unlimited energy source, particularly in comparison with emerging non-nuclear systems such as those based on fuel cells. Operated initially with natural gas- or coal gas-derived hydrogen and ultimately with renewable hydrogen, fuel cells (in particular the high-temperature ones) are becoming the focus of interest for applications in decentralized power and combined heat and power plants, in centralized power stations in the MW range and in the transport sector. Adequately supported, fuel cell technologies can be expected to be commercially established before a hypothetical demonstration of the scientific feasibility of fusion. After a brief review of the historical evolution of major fusion plans, in particular of the next-step projects in Europe, this paper discusses critically the above mentioned aspects of fusion, addressing primarily the most advanced concept, the 'tokamak'. Copyright (C) 1999 John Wiley & Sons, Ltd.