The use of high temperature superconductors (HTS) in long term tokamak fusi
on reactors is analyzed in this paper. The well-documented physical al prop
erties of high temperature superconductors are used in the evaluation. Shor
t-sample wires and tapes of Bi2Sr2CanCun+1Oy. materials, with n = 1, 2 (ref
erred to as BSCCO), and YBCO (YBa2CuO7-x) tapes approach their single-cryst
al performance limits. They provide a useful reference frame as well as a s
tarting point of what may be possible in the future. In this paper, the des
ign issues that arise when this technology is used in tokamak magnet applic
ations will be investigated by extrapolating the properties of short sample
YBCO thick films and BSCCO tapes to longer lengths. The properties of YBCO
operating at elevated temperatures ( > 10 K) will also be summarized. The
limitations imposed on the performance and lifetime of the HTS materials be
cause of the fusion environment will be reviewed. The consequences of imple
menting an HTS configuration in a fusion environment will then be described
. The use of I-ITS material may offer an opportunity for a fundamentally di
fferent approach to magnet design and construction leading to either lower
cost or reduced maintenance. Reduced cost magnets requiring decreased shiel
ding, with better access and easier maintenance may be feasible. (C) 2001 E
lsevier Science B.V. All rights reserved.