To meet its rapidly growing energy demand, some opine that India should pursue research and development on thorium as the future fuel of nuclear energy. In this context, what advantage does thorium hold over uranium? 1. Thorium is far more abundant in nature than uranium. 2. On the basis of per unit mass of mined mineral, thorium can generate more energy compared to natural uranium. 3. Thorium produces less harmful waste compared to uranium. Which of the statements given above is/are correct?

Thorium is approximately three to four times more abundant in the Earth's crust than uranium [1]. Regarding energy yield, thorium can generate more energy per unit mass of mined mineral compared to natural uranium because natural uranium contains only 0.7% fissile U-235, whereas thorium-232 is fertile and can be converted into fissile U-233, allowing for more efficient fuel utilization and higher burnup. Furthermore, thorium produces significantly less long-lived radioactive waste and transuranic elements (like plutonium) compared to the uranium cycle [1]. The radiotoxicity of thorium waste reaches natural levels in about 10,000 years, whereas uranium waste takes nearly 200,000 years. These factors make thorium a promising future fuel for India, which possesses large indigenous thorium reserves in monazite sands [2].

Sources

1. [1] https://www.sciencedirect.com/science/article/abs/pii/S0306454916300305
2. [2] Environment and Ecology, Majid Hussain (Access publishing 3rd ed.) > Chapter 9: Distribution of World Natural Resources > thorium > p. 40