India’s Three Stage Nuclear Programme

• Was formulated by Dr. Homi Bhabha in the 1950s
• India has 25% of world thorium reserves but only 1-2% global uranium reserve
• it will enable the thorium reserves of India to be utilised in meeting the country’s energy requirements

Stage 1 – Pressurised Heavy Water Reactor

• Natural uranium fuelled pressurised heavy water reactors (PHWR) produce electricity

• Natural uranium contains only 0.7% of the fissile isotope uranium-235.
• Most of the remaining 99.3% is uranium-238 which is not fissile but can be converted in a reactor to the fissile isotope plutonium-239
• In PWHR, enrichment of Uranium to improve concentration of U-235 is not required. U-238 can be directly fed into the reactor core

• Generate plutonium-239 as by-product [U-238 → Plutonium-239 + Heat]
• Heavy water (deuterium oxide, D 2O) is used as moderator and coolant in PHWR

Stage 2 – Fast Breeder Reactor

• Would use a mixed oxide (MOX) fuel made from plutonium-239, recovered by reprocessing spent fuel from the first stage, and natural uranium
• plutonium-239 undergoes fission to produce energy, while the uranium-238 present in the mixed oxide fuel transmutes to additional plutonium-239
• Thus, the Stage II FBRs are designed to “breed” more fuel than they consume

• Uranium-235 and Plutonium-239 can sustain a chain reaction. But Uranium-238 cannot sustain a chain reaction, so it is transmuted to Plutonium-239

Stage 3 – Thorium Based Reactors

• an advanced nuclear power system involves a self-sustaining series of thorium-232- uranium-233 fuelled reactors
• This would be a thermal breeder reactor, which in principle can be refueled after its initial fuel charge using only naturally occurring thorium

According to the three-stage programme, Indian nuclear energy could grow to about 10 GW through PHWRs fueled by domestic uranium, and the growth above that would have to come from FBRs till about 50GW

Prototype Fast Breeder Reactor (PFBR)

Prototype Fast Breeder Reactor (PFBR)

• Presently India is heading towards second stage of its nuclear programme
• PFBR is a reactor, which produce more fuel than it consumes
• PFBR is using uranium-238 not thorium, to breed new fissile material, in a sodium-cooled fast reactor design with no moderators required

• Indira Gandhi Centre for Atomic Research (IGCAR) is responsible for the design of this reactor
• 500-MWe Prototype Fast Breeder Reactor (PFBR) at Kalpakkam is getting ready to be commissioned in September.
• It will signal India’s triumphant entry into the second stage of its three-stage nuclear power programme