In the ongoing first stage, India is using pressurised heavy water reactors (PHWRs) using natural uranium. (Natural uranium contains only 0.7% uranium-235; the rest is mostly uranium-238, which can’t sustain a nuclear reaction. Where natural uranium has a burn-up of around 7 GWd/t, HALEU-Th has a burn-up of 50 GWd/t — i.e. As thorium absorbs neutrons more aggressively than uranium, the authors found the reactor’s current shutdown rods became around 26% less effective. Finally, India’s second stage depends on plutonium produced in the first stage, whereas HALEU-Th produced almost 20x less plutonium than natural uranium.

Source: The Hindu March 10, 2026 04:43 UTC