India's three stage nuclear power programme

India's three stage nuclear power programme was formulated to use the available Uranium and Thorium reserves found in the monazite sands of coastal regions of South India. However, the long term focus of the programme is more on enabling the Thorium reserves of India to be utilized in meeting the country's energy requirements, as Thorium is far more abundant in India than Uranium. Importance of nuclear energy was recognised as soon as India became independent. The Atomic Energy Act, 1948 was published with sole intent to develop nuclear research for peaceful purposes.

Stage I - Pressurised heavy water reactor

In the initial stage of the programme, Natural uranium fuelled Pressurised heavy water reactors (PHWR) which would produce Plutonium-239 as by-product, while providing power for the country. Almost the entire existing base of Indian nuclear power (4700MW) is composed of these PHWRs, and all these reactors would come under the first stage of the programme. In addition, the reactors that are under construction at Kakrapar, Rawatbhata and Banswara would also come under the first stage of the programme.

Stage II - Fast breeder reactor

In the second stage, Fast breeder reactors (FBRs) would be used with a fuel that is derived from the Plutonium-239 created in the first stage of the Programme and the country's naturally occurring Thorium-232 reserves, to produce Uranium-233 as a by-product during normal power generation for the country. The Fast breeder reactor at Kalpakkam that is to be commissioned in 2013 would come under this stage of the programme.

India's fast breeder reactor is based upon the LMFBR technology -"Liquid Metal Fast Breeder Reactor." In Indira Gandhi Centre for Atomic Research, liquid sodium metal is used as the coolant in the nuclear reactor. Liquid sodium cools the reactor, carrying heat from the primary vessel to the steam generator, a sodium-water heat exchanger also known as NaX. For chain reaction, a fast reactor must use fuel that is relatively rich in fissile material. The superior neutron economy of a fast neutron reactor makes it possible to build a reactor that, after a relatively large initial fuel charge of Plutonium, requires only natural (or even depleted) Uranium feedstock as input to its fuel cycle.

Stage III - Advanced nuclear power system

See also: Thorium fuel cycle

The Advanced nuclear power system involves a self-sustaining series of thorium-232-uranium-233 fuelled reactors, such as Advanced Heavy Water Reactor(AHWR). It is a thermal breeder reactor, as after its initial fuel charge of enriched Uranium, Plutonium or MOX, it requires only naturally occurring Thorium as input to its fuel cycle.

According to the latest news, the design for AHWR is ready and construction will start after the site is identified in 6 months time from late 2011. It will take another 18 months to get clearances on regulatory and environmental grounds. Construction of the AHWR will begin that timeperiod, and it would take another six years for the reactor to become operational. If everything goes according to plan, the reactor could be operational by the end of the decade.

It is this Stage III technology, in combination with the Stage II technology that enables it, which will radically revolutionize the sustainability of modern industrial civilization. It does so by stretching out the power generation capacity of societies to well over 1000 years, if only the economically mine-able reserves are used; and by some accounts to a period long enough that it is not genuinely forecast-able if all Thorium that is mine-able using Thorium energy infrastructure is used.

See also

• Energy policy of India
• Nuclear power in India
• Energy security
• Indo-US civilian nuclear agreement
• IEEE Spectrum Q&A With: Sudhinder Thakur
• IEEE Spectrum Q&A: Thorium Reactor Designer Ratan Kumar Sinha