Özet:
Intensive effort for energy prduction through alternate paths is being spent in developed countries because of the limitedness of resources such as natural gas, petroleum, coal that make great contributions t o energy production. Nuclear energy can be noted as one of the most important amongst these alternatives. R & D work is being carried out for the purpose of reducing the reliance on the U-235 isotope and for more economical utilisation of known Uranium resources because of the limitedness of the isotope U-235 which plays an important role on today's reactor technology. In this study, the Thorium fuel cycle which offers the possibility of reducing mined Uranium ore requirements is examined in connection with the High Temperature Gas cooled Reactor concept which supports the Thorium cycle. The Pebble-Bed core which employs spherical fuel elements is particularly interesting as it provides On-Load Refuelling. A s a prelude, the first chapter provides the basic information to introduce the concept to the reader. The properties of Thorium material are described in chapter 2. Several Thorium fuel cycles are discussed in chapter 3 and the technology associated with Thorium fuel along with HER designs is introduced in chapter 4. A possible strategy utilising Thorium is examined in chapter 5. The sixth chapter covers information about current HTGR models under active development.