Context: 

Recently, the Prime Minister witnessed the start of core loading for India’s indigenous 500 Mwe Prototype Fast Breeder Reactor (PFBR) in the nuclear plant at Kalpakkam, Chennai.

Background of India’s Nuclear Energy Programme

• Atomic Energy Commission: The Atomic Energy Commission (AEC), set up in 1948 under the leadership of Homi J. Bhabha, marked the beginning of India’s nuclear program.
• Atomic Energy Establishment: In 1954, the Atomic Energy Establishment, Trombay (AEET), was founded, which later became the Bhabha Atomic Research Centre (BARC).
• Nuclear Power: India’s first nuclear power plant was commissioned in 1969 at Tarapur, Maharashtra, which marked a significant step in the country’s nuclear power generation.
• Pokhran Tests: India demonstrated its nuclear capabilities to the world with the peaceful nuclear explosion at Pokhran in 1974, and later in 1998.
• Indigenous Development: Post the Pokhran tests, India faced international embargos which led to the development of indigenous technology for both power generation and strategic purposes.

What is India’s 3 Stage Nuclear Program:

• The goal of the three-stage nuclear programme is to use India’s enormous uranium deposits, which make up around 25% of the global total. 
  • In addition, India only possesses 2% of the world’s uranium deposits, making them scarce.

• Stage I: Pressurized Heavy Water Reactors (PHWRs):

  • Pressurized heavy water reactors (PHWRs) are used in the first phase of India’s three-stage nuclear power development.
  • These reactors create plutonium-239 as a byproduct in addition to power.
  • PHWRs were selected for the first phase because of their effective reactor design, which maximizes the use of uranium.
  • Utilization and Operation of Uranium:
    • Use of Natural Uranium: PHWRs burn natural uranium, which is primarily composed of uranium-238.
    • Production of Plutonium: In a reactor, uranium-238 can be transformed into plutonium-239.
    • Heavy Water Usage: In PHWRs, heavy water, or deuterium oxide, or D2O, is used as a coolant and moderator.
  • PHWR Series: Based on the original Canadian CANDU reactors, India has built a series of PHWRs known as the IPHWR series.
    • Reactor designs with capacities of 220 MWe, 540 MWe, and 700 MWe are part of the IPHWR series.
  • Installed Capacity: First-stage PHWRs from the IPHWR series make up the majority of India’s current nuclear power capacity.
  • Upcoming Developments: In order to augment PHWRs, India is developing reactors based on Pressurised Water Reactor technology, such as the IPWR-900 reactor platform.

• Stage II: Fast  Breeder Reactor (FBR): 

  • Fast breeder reactors (FBRs) are used in the second phase of India’s three-stage nuclear power development.
  • Composition and Type of Fuel:
    • Type of Fuel:  FBRs use a mixed oxide (MOX) fuel composed of plutonium-239 recovered from spent fuel from the first stage and natural uranium.
    • Fission Process: In order to produce energy in FBRs, plutonium-239 undergoes fission.
    • Breeding Fuel: FBRs are able to “breed” more fuel than they consume because uranium-238 in the mixed oxide fuel transmutes to more plutonium-239.
  • Change to Thorium:
    • When there is enough plutonium-239 in stock, thorium can be added to the reactor as a blanket material.

• Stage III: Thorium-Based Reactors:

• • In the third stage of India’s three-phase nuclear power programme, self-sustaining reactors powered by uranium-233 and thorium-232 will be deployed.
  • Features of Reactors:
    • Refueling: Reactors classified as thermal breeder reactors are able to be refuelled with naturally occurring thorium following the initial fuel charge.
    • Fuel Composition: The main fuel used in the reactor is thorium-232, which is converted to uranium-233 to provide energy.
  • Implementation Plan:
    • Capacity Growth: By using PHWRs and FBRs, the third stage is expected to help India’s nuclear energy sector grow beyond 10 GW.
    • Timeline: It is anticipated that full thorium reserve exploitation in India would take place three to four decades after fast breeder reactors begin commercial operations.
  • Other Methods:
    • Indian Accelerator Driven Systems (IADS): To exploit thorium, innovative accelerator-driven systems are being developed in partnership with Fermilab, a US laboratory.
    • Advanced Heavy Water Reactor (AHWR): The Advanced Heavy Water Reactor (AHWR) is a reactor design that is ready for deployment and runs on fuel composed of uranium-thorium MOX and plutonium-thorium MOX. It can use thorium to produce a sizable amount of its electricity.
    • Molten Salt Reactor: An experiment to determine whether molten salt technology can be used to produce thorium is being conducted with the Indian Molten Salt Breeder Reactor (IMSBR).

Prototype Fast Breeder Reactor

• Beginning of Stage II: The country’s three-stage nuclear power programme begins with PFBR, the second stage, where the spent fuel from the first stage will be “reprocessed and used as fuel.”
• Feature: This sodium-cooled PFBR’s ability to create more fuel than it consumes makes it special and contributes to future fast reactors’ ability to become self-sufficient in their fuel supply.
• Design and Construction: The nation’s first fast breeder reactor, the PFBR was created by the Indira Gandhi Centre for Atomic Research (IGCAR).
• Responsibility: The Department of Atomic Energy’s (DAE) public sector enterprise Bharatiya Nabhikiya Vidyut Nigam Ltd (Bhavini) is in charge of constructing fast breeder reactors in India.

Advantages of Fast Breeder Reactors

• Efficient Utilization of Resources: FBRs can utilize uranium more efficiently by converting non-fissile uranium (U-238) into fissile plutonium (Pu-239). An example of this is the Prototype Fast Breeder Reactor (PFBR) at Kalpakkam.
• Reducing Nuclear Waste: FBRs can help in reducing the amount of nuclear waste due to their ability to burn actinides, which are major contributors to long-term radiotoxicity of nuclear waste.
• Energy Security: FBRs are vital for long-term energy security in India, which has limited reserves of uranium but abundant reserves of thorium. This thorium can be converted into fissile uranium-233 in FBRs.