India, a country with a burgeoning population and with very high power needs, was short on the energy resources whether it be petroleum or good quality coal. But there was one power source India had in abundance which could potentially power it for almost 6 centuries on its own which was THORIUM. Thorium is one of the actinide metals which can theoretically be used for nuclear power generation by converting the Thorium-232 to Uranium-233. Naturally occurring Thorium by itself is not a radioactive element. Hence it is necessary for the conversion of Thorium into Uranium through nuclear reactions.
Homi Jehangir Bhabha was the eminent Indian Nuclear Scientist who was aware of the potential that India’s Thorium reserves had and he was also aware of the very low Uranium-235 reserves present in India. This resource demography made it necessary for India to utilize Thorium for its nuclear power reactors in order to achieve self sufficiency. But at the start of the nuclear programme the nuclear scientist faced the non-availability of nuclear research in the field of Thorium enrichment for use in nuclear reactors. This led to initialization of one of the most innovative nuclear programme in the world which was named as ‘The Three Stage Nuclear Programme’.
During the early years of nuclear research the international scientific community thought that the radioactive Uranium reserves present on Earth was very less and hence showed interest in utilizing Thorium as a fuel which was abundant in the earth’s crust. But after some years of exploration, large deposits of Uranium were found world over. This led to a sharp decline in the cost of the Nuclear power produced through Uranium. Due to this the interest in Thorium research dwindled as the complexities in its enrichment were very high and hence escalated its costs which made its research and commercialization non-viable. Unlike the other nations, very small deposits of radioactive Uranium was found in India and this made it necessary for the Indian Government to authorize the Thorium enrichment research which was undertaken under the Three Stage Nuclear Power Programme.
Dr. Bhabha split the whole nuclear power programme into three stages with a particular reactor design and power generation target in mind. He envisaged proper utilization of the Uranium reserves in order to make power production through Thorium self sufficient. The three stages of the nuclear expansion are as follows:
- Stage 1: The stage 1 envisaged construction of Pressurized Heavy Water Reactors (PHWR) which could use natural uranium to produce electricity with Plutonium-239 as a by-product. Today almost all of the nuclear plants installed in India are PHWRs. It was determined that the Uranium reserves in India could only support up to 10 GW of power capacity and hence it was kept as a target which when achieved would kick start the Stage 2 of the nuclear programme. Since in 1950s, when this programme was started the PHWR was easily available hence it was adopted for easy installation of these reactors as India had the required technical expertise to operate such reactors. But after the embargo placed on India due to the 1974 nuclear test, the development of this stage slowed down and India had to develop its own reactors in order to achieve its objectives.
- Stage 2: The objective of stage 2 was to develop upon the expertise and fuel generated through the stage 1 reactors by developing fast breeder reactors which would use plutonium generated as byproduct in the stage 1 reactors for its fuel cycle. The Stage 2 have been designed to ‘breed’ more fuel than they consume by converting the Uranium-238 present in the mixed oxide fuel to plutonium-239. A target of 50 GW power generation through these reactors has been set up. With the setting up of new stage 1 reactors at various sites, India has almost achieved its goal of generating 10GW power through stage 1. This in effect has initiated the stage 2 of the program. This stage is necessary as when the required inventory of plutonium is achieved then Thorium can be introduced as a blanket material which will be converted to Uranium-233 to be used in the Stage 3 reactors. BARC has developed India’s first Prototype Fast Breeder Reactors and India has also undertaken construction of 4 more FBR at various locations in the country.
- Stage 3: Stage 3 is the Holy Grail for India which when completed will completely transform the Indian subcontinent and this is the goal toward which India is working relentlessly and due to this India is at the forefront of Thorium nuclear research. Stage 3 envisages development of Nuclear Reactors which can use thorium as the fuel for the power generation. Stage 3 reactors can only be developed when India would achieve the stage 2 goal of 50 GW power through FBR. Hence no significant effort has been put forward for this stage. Due to all the embargos and miscalculation of the inherent processes involved in the setting up of nuclear plants the initial timeline for the completion of all the three stages has been shifted from 30 years to 70 years. This means that the Thorium reactors will only be available after 2050 for power generation.
The timeline involved in the development of the three stage nuclear programme is very long but India has continued to step forward on the path illuminated by it. But India has also taken parallel approaches to develop its Thorium nuclear reactor. One of the options developed by India is the Advanced Heavy-Water Reactor which is slated to be used in the stage 3 of the nuclear programme. BARC has completed the design of the AHWR and is slated to start the construction of 300MW prototype reactor. AHWR has been one of the few reactors in the world that have already strived to meet the requirements of innovative next-generation nuclear reactors as has been spelt out in several international forums.
The Nuclear Programme of India is surely moving forward in the right direction albeit slowly but this delay cannot be criticized as India’s nuclear programme is an uncharted territory which can hold many surprises for its explorers. With the recent finding of new Uranium reserves in India and the Indo-US nuclear deal has provided a shot in the arm for the stage 1 and 2 of the program as it has enabled ample supply of the nuclear fuel for coming decades and free trade opportunities for latest nuclear technology which India had to develop on its own if the embargo on its nuclear programme had not lifted. The next few years will be quite eventful for Indian nuclear research with the development of new prototype reactors and setting up of new commercial reactors. This has surely instilled new vigor in the program and the scientist working on it. The road forward is harsh but no doubt India will continue to move forward against all odds just like it has done all these years and will achieve new milestone in the nuclear research.