THORIUM BREEDER REACTOR EVALUATION. PART I. FUEL YIELDS AND FUEL CYCLE COSTS OF A TWO-REGION MOLTEN SALT BREEDER REACTOR

The MSBR (lOOO Mwe station) is capable of giving fuel yields of about T^yr (doubling time = \\ years) at a fuel cycle cost of approximately I.5 mills/kwhr.At fuel yields of 1 to 256/yr (DT = 100 to 50 years), the fuel cycle cost extrapolates to 0.65 mills/kwhr; at 4^/yr (DT = 25 years), the fuel cycle cost is about 0.85 mills/kwhr.All systems were optimized with respect to fuel cycle processing times.The effects on breeding performance of uncertainties in the epithermal value of 11-233^ uncertainty in value of the resonance integral of Pa-233, variable thorixm inventory in fertile stream and inclusion of ZrF* in reactor fuel were evaluated.These effects may be summarized as follows:1.A ±10^ variation in the epithermal value of Ti-233 from "recommended" value causes a ±2.5 to ±3Vy^ variation in fuel yield but only a ±0.o6 mills/kwhr variation in fuel cycle cost.2. Using 900 barns instead of 1200 barns for Pa-233 resonance integral has only a small effect on breeding performance; the lower value increases fuel yield about 0.25^/yr and lowers fuel cycle cost about 0.01 mills/kwhr.3. Doubling the thorivim inventory adds about 1.9^/yr to fuel yield and 0.2 mills/kvdir to fuel cycle cost. h.Five mole $ ZrF4 in LiF-BeFg-UF* fuel salt decreases fuel yield about 0'%/yv, but fuel cycle cost is negligibly affected.