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7-22
Even with government support, achieving the postulated schedules would be a difficult
undertaking and would entail considerable risk since it would be impossible to fully
demonstrate an alternate reactor concept before construction on the initial comnercial
size units has to begin. A minimum of six years would be required to construct a nuclear
unit, and a minimum of three years would be required prior to construction for R&D and
licensing approval.
(It currently takes 10 to 12 yr to license and construct LWRs in
the U.S.) At least two additional years of operation of the demonstration unit would be
necessary to establish satisfactory reactor performance. Thus the earliest time a new
reactor concept could be demonstrated is in the 1991-1995 period indicated, and that
assumes that a commitment to proceed has been made by 1980. Because of design, licensing,
and construction schedules, the first comnercial units would have to be ordered well in
advance of the operation of the initial demonstration reactor to achieve the buildup
rates assumed in this study. In order to achieve such commitments prior to the first
successful demonstration, government support would have to extend through the initial
commercial units in addition to the lead plant. The new reactor cycle would also have to
be perceived as economically advantageous to attract the postulated number of customers.
A1 though several of these reactorlfuel options (e.g., PuITh LWRs, denatured advanced
converters, etc.) are based on the use of recycled fissile material, it should be emphasized
that comercial-scale reprocessing is not necessarily required on the same time scale as the
introduction of the recycle fuel types because the demand for recycle fissile material may
be quite modest during the initial introduction phase. In the analysis presented in
Chapter 6, many of the new fuel types are, in fact, introduced before the associated fuel
reprocessing is fully developed, it being assumed that pilot or prototype-plant scale
reprocessing would be adequate to support the initial phase of deployment of fuel recycle.
Hence, although commercial reprocessing of 233U-containing fuels is not projected until
around the turn of the century, limited introduction of denatured 233U fuel is permitted
as early as 1991. A further argument is that commercial-scale reprocessing for the
alternate fuels would not be feasible until the backlog of spent fuel required for plant
startup had accumulated and the number of reactors utilizing recycled fuel could assure
continued operation of commercial-scale facilities. On the other hand, for 33U-containing
spent fuel elements to be available even for pilot-plant processing, it is essential that
early irradiation of thorium in reactors be implemented.
In Section 7.3.1 a possible procedure for implementing and eventually commercializing
the denatured 233U cycle is discussed.
Included is a scenario which would provide for the
early introduction of thorium fuel into current light-water reactors and allow an orderly
progression to the utilization of denatured 23% fuel in breeders.
The major considera-
tions in commercializing these various reactors operating on alternate fuels, and in
particular on denatured 233U fuel, are sumnarized in Section 7.3.2.
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