1. 1/10 VUJE, Inc., Okružná 5, 918 64 Trnava, Slovakia; FEI STU, Ilkovičova 3, 81219 Bratislava, Slovakia Thorium Fuel Cycle Under VVER and PWR Conditions 17 th Atomic Energy Research Symposium Yalta, Crimea, Ukraine 24-28 September 2007 Juraj BREZA 1,2, Petr DAŘÍLEK 2, Vladimír NEČAS 1 breza@vuje.sk, darilek@vuje.sk, vladimir.necas@stuba.sk 1 VUJE Inc., Okružná 5, 91864 Trnava, Slovakia 2 Slovak University of Technology, Faculty of Electrical Engineering and Information Technology, Ilkovičova 3, 81219 Bratislava, Slovakia

2. 2/10 VUJE, Inc., Okružná 5, 918 64 Trnava, Slovakia; FEI STU, Ilkovičova 3, 81219 Bratislava, Slovakia CONTENTS  Motivation  Thorium fuel scenario  Results  Conclusions

3. 3/10 VUJE, Inc., Okružná 5, 918 64 Trnava, Slovakia; FEI STU, Ilkovičova 3, 81219 Bratislava, Slovakia  Study of thorium fuel cycle and its application on VVER-440 and PWR reactor  Plutonium transmutation under light water reactor conditions  Participation in project RED-IMPACT focused on advanced fuel cycles MOTIVATION

4. 4/10 VUJE, Inc., Okružná 5, 918 64 Trnava, Slovakia; FEI STU, Ilkovičova 3, 81219 Bratislava, Slovakia Enriched U UOX Fabrication VVER-440 (UOX core) STORAGESTORAGE Final Disposal 4.2 wt% U-235 UOX Open fuel cycle SCENARIOS

5. 5/10 VUJE, Inc., Okružná 5, 918 64 Trnava, Slovakia; FEI STU, Ilkovičova 3, 81219 Bratislava, Slovakia Pu-Th MOX fuel cycle (VVER-440) Enriched U UOX Fabrication VVER-440 (UOX core) STORAGESTORAGE Waste 4.2 wt% U-235 PuThOX Fabrication VVER-440 (PuThOX core) Reprocessing URT UOX Pu - all isotopes PuThOX ThOX FP MA 0.1% Pu 0.1% U U 9.74 wt% Pu (5.40 wt% Pu-239) 1.24 wt% Pu SCENARIOS

6. 6/10 VUJE, Inc., Okružná 5, 918 64 Trnava, Slovakia; FEI STU, Ilkovičova 3, 81219 Bratislava, Slovakia Model of VVER-440 assemblyModel of PWR assembly COMPUTATION MODELS

7. 7/10 VUJE, Inc., Okružná 5, 918 64 Trnava, Slovakia; FEI STU, Ilkovičova 3, 81219 Bratislava, Slovakia target burnup: 50 GWd/tHM core cycle: 320 days, 5 years INPUT DATA Pu content estimation for VVER-440 thorium cycle Pu content estimation for PWR thorium cycle

8. 8/10 VUJE, Inc., Okružná 5, 918 64 Trnava, Slovakia; FEI STU, Ilkovičova 3, 81219 Bratislava, Slovakia RESULTS

9. 9/10 VUJE, Inc., Okružná 5, 918 64 Trnava, Slovakia; FEI STU, Ilkovičova 3, 81219 Bratislava, Slovakia  Both investigated reactors fully loaded with thorium- plutonium fuel can transmute about 46 kg of Pu/tHM but PWR has a better efficiency  Introduction of an advanced fuel cycle in light water reactors does not solve the problem of plutonium burning; it only allows producing less of plutonium than it is produced today with classical UOX fuel  In the case of non-equilibrium cycles, where plutonium will be obtained from the stock of spent fuel, thorium fuel allows to burn Pu into approx. 50% of today store CONCLUSIONS

10. 10/10 VUJE, Inc., Okružná 5, 918 64 Trnava, Slovakia; FEI STU, Ilkovičova 3, 81219 Bratislava, Slovakia Thank you for your attention