The US Fast Breeder Reactor Development Programme U.S. CIVILIAN REACTOR DEVELOPMENT STRATEGY* The world energy problem has spared few nations from its effects. While there are many common aspects of the problem which nations face, each nation likewise has its own distinct set of requirements, resources and relationships which inevitably shape the direction of its national policies and programs. U.S. energy strategy is directed toward achieving energy self-sufficiency. Among the important implications of this policy are increased use of coal, including its conversion to gas and petroleum liquid to compensate for diminishing supplies of gas and oil, increased utilization of nuclear power, and the development of new energy technologies. Nuclear power will be required to provide a larger share of total electric energy demand than hitherto projected and the pace of constructing and licensing nuclear plants will need to be stepped up. U.S. civilian reactor strategy is based on LMFBR Priority recognition that domestic uranium (and LMFBR has had a history of over 20 years thorium) resources taken as those which can of successful technology development. be utilized in ways that are economically Progress in the LMFBR program, reasonable and environmentally acceptable particularly since the late 1960's, has been are finite, and that the breeder is needed encouraging. Economic projections based soon to assure long-term energy supply. It on increased experience in the U.S. and is also based on the fact that, of the over abroad, and on continuing economic 200 nuclear power plants now in operation, analyses, support the case for the earliest under construction or on order in the U.S., introduction of the LMFBR system into the preponderance arS of the light water utility systems consistent with technological reactor (LWR) type, which operate on the and industrial capability. Program uranium-plutonium cycle. This requires experience and repeated analyses have both that initial use of the breeder be on the validated the decision to accord priority same fuel cycle. Consistent with this to the LMFBR. Independent technical and requirement, the U.S. highest priority effort economic reviews, and the priority given is on the Liquid Metal Fast Breeder the LMFBR by France, Germany, Italy, Reactor (LMFBR). Japan, the U.K. and the USSR, reinforce the While the U.S. priority effort is on the U.S. position in this matter. LMFBR, the wisdom of providing other reactor options has been recognized. To this LMFBR Program Implementation end the U.S. is carrying forward technology The breeder program can be characterized efforts on a number of other concepts, as as consisting of two major phases: the first will be discussed later in the paper. phase is "research and development"; the * Condensed from a paper by: T. Nemzek, USAEC; R. Laney, Argonne National Laboratory; A. Squire, Hanford Engineering DEvelopment Laboratory; S. lacobellis, Rockwell International; B. Wolfe, General Electric Company; J. Landis, General Atomic Company; J. Taylor, Westinghouse Electric Corp. March 1974 37 SIZE • SAFETY • PERFORMANCE TECHNOLOGY DEVELOPMENT- PREDICTABILITY- ECONOMY COMMERCIAL PHASE LMFBR PROGRAM UTILITIES CHOOSE TO BUY LMFBR's DEMO DEMO COMPONENTS & SYSTEMS OPERATION ELECTRICAL PRODUCTION ECONOMICS PUBLIC ACCEPTANCE ADVANCED FUELS & MATERIALS SAFETY COMPONENTS & SYSTEMS OPERATION BASE TECHNOLOGY 1950 1960 1970 1980 1990 second is "utility commitment". The development effort to complete and advance first phase includes all of the necessary the development of technology cannot be research and development such as the over-emphasized. This is an indispensable establishment of the basic technology in requirement of a successful program to areas like fuels, materials, physics and heat develop nuclear energy systems adequate to transfer. It includes concept selection and meet U.S. national needs. the development of capability to build reliable components and it includes Within this context a first step toward successful demonstration of the concept to achieving a truly national program was the preparation of a formal LMFBR Program produce electricity on a utility system. Plan, developed over a period of three The second phase, termed "utility years with the assistance of all the major commitment", is reached when, by their program participants, and first issued in choice, utility companies repeatedly select 1968. This plan was recently revised and the developed concept as a power plant for re-issued to reflect the advances in their systems. technology and the more precise definition Of necessity a strong technology program of objectives which had taken place since. must underlie both phases. The importance Preparation of the Program Plan provided a of sustaining a strong research and forum for decision making in that it 38 included reviews and participation by fuel assemblies and other reactor materials industry, national laboratories, the electric at a combination of conditions (neutron utilities and the USAEC. In its development flux, specific fuel power rating and there was an underlying emphasis on temperature) corresponding to those in facilities; facilities to permit testing of large commercial reactors. The FFTF's physics, fuel, components and closed loops and extensive instrumentation instrumentation; facilities to design and will give the U.S. program a flexible proof-test needed components and to capability for testing and measuring the serve as a focal point for identifying actual performance of fuels and materials. and hard needs for research and development, and as vital building blocks In designing and constructing the FFTF a with which industry capability could be program has been developed that goes developed. considerably beyond the engineering design of the FFTF itself. This program has an Central to achieving breeder capability is objective of testing fuels, materials and the reactor itself. Full understanding of components under conditions as near as material and fuel performance in the special possible to LMFBR operational environment of the reactor core is vital requirements. Thus, FFTF is providing a to the success of any reactor system. The focusing mechanism and pace and relevance fast breeder reactors have a particularly for the entire LMFBR program. difficult problem resulting from damaging The next and most recent step in our effects of fast neutron irradiation on breeder program has been the initiation of structural and fuel materials. For this reason, work on the first breeder Demonstration the U.S. program has placed emphasis Plant. A partnership agreement among the on developing capability for acquiring the AEC and two of the major utility systems best possible understanding of materials in the United States — Commonwealth behavior in the fast breeder environment Edison and the Tennessee Valley and developing materials which can meet Authority — was signed in July 1973 to the demanding conditions of this build the 380 MWe Clinch River Breeder environment. This program required Reactor (CRBR) in the State of Tennessee. converting an existing facility, the EBR-II, Utility industry support for the CRBR to an irradiations test reactor, increasing includes financial contributions in excess of its plant capacity factor, and its power level, $ 240 million from about 350 investor improving the capability for and publicly-owned electric utilities. instrumentation of tests, and changing much of the fuel loading from the initial metal All these steps are pre-requisites to entering fuel to the fuels of interest in early fast the "utility commitment" phase when the breeder reactors. However, EBR-II has utilities will have sufficient confidence limitations with respect to core height, flux in their breeder system so that it will be density and neutron energy spectrum and chosen for general use. Discussion is going the lack of closed loops. on as to the additional measures by which this phase will be approached. These limitations and other considerations lead logically to the further step of Alternate Breeder Concepts designing and constructing the Fast Flux Test Facility (FFTF). As mentioned earlier, other breeder options The FFTF will provide a powerful capability are being held open by carrying forward for evaluating the performance of reactor technology development efforts for reactor 39 concepts such as the Light Water Breeder The GCFR concept appears attractive as a Reactor (LWBR), the Molten Salt Breeder parallel effort to the LMFBR. Its good Reactor (MSBR), and the Gas-Cooled Fast neutron economy leads to high breeding gain, Breeder Reactor (GCFR). Successful and its high temperature gas coolant leads development of the LWBR would make to high plant efficiency, as well as the available about 50% of the potential energy long-range possibility of use in conjunction of thorium fuel resources. Successful with a direct cycle gas trubine. completion of LWBR breeding demonstration in the Shippingport reactor, The GCFR would be characterized by a scheduled for operation in 1975, would fully integrated nuclear steam supply system demonstrate technical feasibility of enclosed in a reliable pre-stressed concrete converting cores in existing and future reactor vessel. The coolant would be LWRs to the LWBR mode of operation. The circulated by steam-turbine-driven axial MSBR, also a thorium cycle thermal blowers. The primary circuit would be breeder, has promise for efficient use of backed up by at least two auxiliary coolant thorium fuel resources in part resulting