Abstract
The ambience within which fusion development planning is undertaken is changing.
Recent publications by the Intergovernmental Panel on Climate Change and by the Stern
Review (by the former Vice-President and Chief Economist of the World Bank) have
removed most of the residual uncertainties about the reality, causation, pace and cost of
climate change. European and Governmental decisions, and demonstrations of public
support, have displayed increasing commitment to mitigating climate-changing emissions.
It is becoming more widely appreciated that during the second two-thirds of this century
continued world economic development, and continued growth in energy consumption, must
co-exist with the reduction of carbon emissions to very low levels, and that this will give rise
to large political and economic forces. The concluding of the ITER Treaty and the Broader
Approach Agreement has removed much uncertainty relating to the near-term steps of fusion
development. Concerns over energy security and diversity of supply have also markedly
increased.
Thus, it has become reasonable to plan on the assumption that in twenty years time
ITER and IFMIF will have been successful and the world will be eager for clean, secure
energy supplies. Previously published ‘fast track’ scenario studies all assumed a sequential
model of fusion development, severely constrained by funding. The present paper explores
the economic justification for relaxing these assumptions, drawing on the lessons to be learnt
from self-consistent energy/environment/economics modelling, and the resulting potential
for more rapid, but cost-effective, fusion deployment. This includes the consideration of the
acceptability of reduced targets for the economic performance of the first generation of
power plants (as might be evinced, for example, by pulsed operation or ITER design-basis
plasma physics, lower fluence-limited lifetime for some components, and lower power
density), and overlapping of development stages with risks controlled and options held open
by broadening of the development stages, for example by several IFMIF and DEMO
devices.
