Thorium-Based Nuclear Reactors In India
India had chalked out a three-stage nuclear power program to use Thorium as a viable and sustainable option, right at the inception of its nuclear power program.
India has the largest deposits of Thorium in the world. However it is not possible to build a nuclear reactor using Thorium (Thorium-232) alone due to its physics characteristics. Thorium has to be converted to Uranium-233 in a reactor before it can be used as fuel.
Thus the three stage nuclear power program thus aims to use of the domestically available fissile resource by first mixing it with natural Uranium in Pressurised Heavy Water Reactors, followed by mixing it with Plutonium obtained from the spent fuel of Pressurized Heavy Water Reactors, in Fast Breeder Reactors.
Large scale use of Thorium will subsequently follow making use of the Uranium-233 that will be bred in Reactors. The utilisation of Thorium, as a practically inexhaustible energy source, has been contemplated during the third stage of the Indian Nuclear Program.
As is the case with generation of electricity from coal, there will be no emission of greenhouse gases from Thorium and therefore, it will be a clean source of energy.
Development of technologies pertaining to utilisation of thorium has been a part of ongoing activities in the Department of Atomic Energy. With sustained efforts over the years, India has gained experience in different areas of the Thorium fuel cycle.
Efforts are currently on to enlarge the present Thorium related R&D work and activities to a bigger scale and towards development of technologies for the third stage of our nuclear power program. Safety has been accorded paramount importance in all Thorium technology development studies.
Commercial utilisation of Thorium, on a significant scale, can begin only when abundant supplies of either Uranium-233 or Plutonium resources are available.
Accordingly, the large-scale introduction and utilization of Thorium in the program has been contemplated after an adequate inventory of Plutonium becomes available from our Fast Breeder Reactors (FBRs), comprising the second stage of the Indian nuclear power program.
The first commercial Fast Breeder Reactor should be going on steam by March 2026. Thereafter we will be setting up a number of FBRs.
Then after a decade or two of large scale deployment of FBRs there will be enough Plutonium to start a never ending Thorium cycle.
In preparation for the utilisation of Thorium in Third Stage of India’s Nuclear Power Program, efforts towards technology development and demonstration are being made now so that a mature technology for Thorium utilisation is available in time.
