|Fig. 1: Homi Bhabha. (Source: Wikimedia Commons)|
Dr. Homi Bhaba devised India's three-stage nuclear power program in the 1954. It was formulate to provide energy security to India. The main aim was to capitalize on India;s vase thorium reserves while accounting for its low uranium reserves. India has only about 2% of the global uranium reserves but 25% of the world;s thorium reserves. 
The three stages are: 
Natural uranium fuelled Pressurized Heavy Water Reactors (PWHR)
Fast Breeder Reactors (FBRs) utilizing plutonium based fuel
Advanced nuclear power systems for utilization of thorium
The first stage involved using natural uranium to fuel Pressurized Heavy Water Reactors to produce electricity and producing plutonium-239 as a byproduct. Using Pressurized Heavy Water Reactors rather than Light Water Reactors was the best choice for India given its infrastructure. While Pressurized Heavy Water Reactors used unenriched uranium, Light Water Reactors required enriched uranium. Also, the components of PWHR could be domestically manufactured in India, as opposed to LWRs, which would need some components to be imported. Furthermore the byproduct plutonium-293 would be used in the second stage. 
The second stage involves using plutonium-239 to produce mixed-oxide fuel, which would be used in Fast Breeder Reactors. These reactors have two processes. Firstly plutonium 293 undergoes fission to produce energy, and metal oxide is reacted with enriched uranium reacts with mixed-oxide fuel to produce more plutonium-239. Furthermore once a sufficient amount of plutonium-239 is built up, thorium will be used in the reactor, to produce Uranium-233. This uranium is crucial for the third stage. 
The main purpose of stage-3 is to achieve a sustainable nuclear fuel cycle. The advance nuclear system would be used a combination of Uranium-233 and Thorium. Thus India's vast thorium would be exploited, using a thermal breeder reactor. Currently this stage is still in the research stage. Thus India is looking to simultaneously using its thorium in other technologies. The options include Accelerator Driven Systems (ADS), Advanced Heavy Water Reactor (AHWR) and Compact High Temperature Reactor (CHTR). [5,6]
Currently India has 21 reactors that produce 5780 MW, 6 under construction aimed to produce 4300 MW and 33 planned aimed to produce 33000 MW. Currently India's installed capacity of energy is 230,000 MW so nuclear energy could form a significant portion of India's energy output. 
© Shiv Parekh. The author grants permission to copy, distribute and display this work in unaltered form, with attribution to the author, for noncommercial purposes only. All other rights, including commercial rights, are reserved to the author.
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 S. A. Bhardwaj, "Indian Nuclear Power Programme - Past, Present and Future," Sadhana 38, 775 (2013).
 R. G. Busher, "India's Baseline Plan for Nuclear Energy Self-Sufficiency," Argonne National Laboratory, ANL/NE-009/03, January 2009.
 M. R. Srinavasan, "A Nuclear Dream Is Set to Come True," Deccan Chronicle, 29 Dec 13.
 A. Kalam and S. P. Singh, "Nuclear Power Is Our Gateway to a Prosperous Future," The Hindu, 6 Nov 11.
 S. Banerjee, R. K. Sinha and S. Kailas, "Thorium Utilization for Sustainable Supply of Nuclear Energy," J. Phys. Conf. Ser. 312, 062002 (2011).
 "Energy Statistics 2013," Central Statistics Office, Government of India, March 2013.