Fast reactor energy characteristics

The fast reactor has characteristics which make it likely that most of the uranium atoms in natural uranium can be consumed by the process known as breeding. Consequently, if this type of system can be developed a nuclear energy electricity generating system should operate with a much smaller supply of fuel than in the case of natural uranium or slightly enriched uranium thermal fission reactors. The advantages of the fast reactor are therefore bound up with the cost and availability of uranium ores. 

A. Netchaev, et al., Safety Characteristics of the Multipurpose Fast Reactor (MPFR) , Annals of Nuclear Energy, 28, 1717-1732 (2001). 

Taking into account that energy stored in the coolant (heating, chemical and compression potential energy) is minimal in comparison with other coolants used and previously mentioned physical special characteristics of fast reactors and RI integral design, one could look forward to designing the RI of ultimately achievable self-protection. 

Analysis of the characteristics of liquid-metal coolants, such as sodium (Na), lead (Pb) and lead-bismuth eutectic (Pb-Bi), makes it possible to decide on the coolant for the new fast reactor considered as a basic component of large-scale nuclear power, which will be capable of taking over the greater part of the electricity generation increase and, possibly, of providing for other energy-intensive processes. 

Fast reactors hold a unique role in the actinide management mission because they operate with high-energy neutrons that are more effective at fissioning actinides. The main characteristics of the SFR for actinide management mission are ... 

Neutronic calculations show that fast neutron fluxes at fusion reactor magnet locations are rather high and the energy deposited by neutrons compares to or exceeds that by y-rays [2]. It is therefore important to establish the characteristics of radiation damage due to fast neutrons in comparison with those due to y-rays. 

The projections are based on a recent forecast (Case B) by the Energy Research and Development Administration (ERDA) of nuclear power growth in the United States (2) and on fuel mass-flow data developed for light water reactors fueled with uranium (LWR-U) or mixed uranium and plutonium oxide (LWR-Pu), a high temperature gas-cooled reactor (HTGR), and two liquid-metal-cooled fast breeder reactors (LMFBRs). Nuclear characteristics of the fuels and wastes were calculated using the computer code ORIGEN (3). 

The Chapter is organized as follows. First, some fuel cycle characteristics used in comparative analysis of energy systems with different reactors are introduced. Second, open fuel cycle features and support strategies are surveyed for the nearer-term concepts. Then, the several proposed fuel cycle features and support options for the closed cycle concepts are surveyed. After that, fuel and ore resource utilization efficiencies for small reactors with long refuelling interval are discussed and are compared to those of standard light water reactors (LWRs) and typically projected liquid metal cooled fast breeder reactors (LMFBRs). Implications on fuel cycle costs are discussed, and the notion of fuel leasing is presented. 

The classification of the neutron-energy spectrum of a given reactor is determined principally by the neutron-moderating materials which it contains. If the nuclear masses of the nonfuel components of the reactor are relatively low, then the neutron spectrum will correspond to that of a thermal reactor (cf. Fig. 1.4c) if they are large, a fast spectrum will result (cf. Fig. 1.4o). The spectrums of intermediate reactors may be due to a number of nuclear characteristics, the presence of nuclear masses of moderate magnitudes being one cause. 

T. Jevremovic, Y. Oka and S. Koshizuka, Conceptual Design of an Indirect-Cycle, Supercritical Steam Cooled Fast Breeder Reactor with Negative Coolant Void Reactivity Characteristics, AnraA of Nuclear Energy, Vol. 20, 305-313 (1993)... 

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