Sustainability and economy of energy supply with HTGR fueled by uranium from seawater

Fukaya, Yuji   ; Goto, Minoru  ; Ohashi, Hirofumi ; Tachibana, Yukio ; Kunitomi, Kazuhiko 

Sustainability and economy of energy supply with HTGR fueled by uranium from seawater have been investigated. To sustain the nuclear energy safely by electricity generation with HTGR, the uranium resources must be inexhaustible. Uranium exists in seawater as a solute of huge amount, which is 4.5 billion tons and corresponds to a duration period of approximately 70 thousand years. The uranium dissolved in seawater is in an equilibrium state with the uranium on surface of sea floor, which is approximately a thousand times of the amount dissolved in seawater. This suggests that almost all of the uranium, which is 4.5 trillion tU and corresponds to the duration time of 70 million years, can be recoverable. The uranium from seawater is almost inexhaustible natural resource. The economy of electricity generation using uranium from seawater is assessed for HTGR. As a result, HTGR can realize lower cost than that of LWR using conventional uranium.