Thorium vs. Uranium: Global Energy Futures
Thorium is approximately three times as abundant as uranium in the earth’s crust, reflecting the fact that thorium has a longer half-life. In addition, thorium generally is present in higher concentrations (2-10%) by weight than uranium (0.1-1%) in their respective ores, making thorium retrieval much less expensive and less environmentally damaging per unit of energy extracted. Countries with significant thorium mineral deposits include: Australia, India, Brazil, USA, Canada, China, Russia, Norway, Turkey, Venezuela, Sri Lanka, Nigeria, South Africa, and Malaysia.
Naturally occurring thorium has one isotope- thorium-232. In the DBI reactor, the initial start up fuel mix is a combination of thorium and uranium-235. The uranium acts as the “seed” source of neutrons needed to achieve criticality for the first reactor. This combination of fuels decreases the time and capital required to start the thorium fuel breeding cycle. As the DBI reactor design begins producing electricity, Uranium-233, bred from the Thorium-232, increased core reactivity and power output. Over time, the original uranium-235 is burned up and subsequently the reactor is fuelled only with Thorium-232. Over the life of the DBI reactor design (approx. 60 years), about 3% of the original load mass (thorium only) will be added every 18 months. Depending upon operational choices available with the DBI designs, no or very little additional uranium will be needed. _DBI
More information on the future of thorium energy: Flibe