The status of India’s nuclear programme

The status of India’s nuclear programme

Subject: Science and tech

Section: Nuclear Technology

Context:

• On March 4, Prime Minister Narendra Modi witnessed the start of the process of core-loading the indigenous Prototype Fast Breeder Reactor (PFBR) at the Madras Atomic Power Station in Kalpakkam, Tamil Nadu.

What is PFBR?

• The Prototype Fast Breeder Reactor (PFBR) is a significant advancement in nuclear technology, designed to produce more nuclear fuel than it consumes.
• This reactor marks a pivotal point in India’s nuclear power strategy, representing the commencement of the second stage of India’s three-stage nuclear power programme.
• Initially, India utilized Pressurised Heavy Water Reactors (PHWRs) and natural uranium-238 (U-238) as the primary fissile material in the first stage, producing plutonium-239 (Pu-239) and energy through nuclear fission processes involving U-235 and heavy water as a neutron moderator.
• In the second stage, the PFBR will use Pu-239 along with U-238 to generate energy, U-233, and additional Pu-239. This step is facilitated by Bharatiya Nabhikiya Vidyut Nigam Ltd. (BHAVINI), established by the Department of Atomic Energy (DAE) in 2003.
• The final stage involves combining Pu-239 with thorium-232 (Th-232) to produce energy and U-233. This strategic progression, conceptualized by Homi J. Bhabha, leverages India’s substantial thorium reserves, aiming to achieve self-sufficiency in nuclear energy for the country.

Why was the PFBR delayed?

• The development of the Prototype Fast Breeder Reactor (PFBR) in India has been fraught with setbacks, including prolonged delays, escalating costs, and several broken commitments, attracting a wide array of critics.
• There were international sanctions imposed on India after the ‘Smiling Buddha’ nuclear test, necessitating a switch from the planned enriched uranium to a mixed carbide fuel.
• Additionally, technical issues with the reactor coolant further contributed to the project’s delay, pushing the commercial operation deadline to October 2022.

How does PFBR work?

• The Prototype Fast Breeder Reactor (PFBR) operates on the principle of using a breeder reactor mechanism, where it generates more fissile material (plutonium-239, Pu-239) than it consumes.
• In contrast to Pressurised Heavy Water Reactors (PHWRs) that utilize natural or low-enriched uranium-238 (U-238) and produce Pu-239 as a byproduct, the PFBR takes this produced Pu-239 and combines it with additional U-238 in a mixed oxide form. This mixture is then loaded into the reactor’s core along with a breeder blanket, a layer that interacts with the fission products to create more Pu-239.
• A distinctive feature of the PFBR is its use of fast neutrons (hence “fast” in the name), which are not moderated or slowed down, enabling certain fission reactions that contribute to the breeding process.
• The reactor uses liquid sodium as a coolant in two separate circuits for safety and efficiency. The primary circuit carries the coolant through the reactor core, absorbing heat and radioactivity, and then passes the heat (but not the radioactivity) to a secondary coolant circuit through heat exchangers.
• This secondary circuit then uses the transferred heat to generate electricity.
• Challenges in operationalizing the PFBR have been noted, including the complex behavior of its systems in practical settings compared to theoretical expectations. For instance, the process of preheating the reactor vessel to 150 degrees Celsius took significantly longer than anticipated.

What role can SMRs play?

• Small Modular Reactors (SMRs) are emerging as a promising alternative to traditional large-scale nuclear reactors, especially in the wake of delays experienced with projects like the Prototype Fast Breeder Reactor (PFBR).
• With a maximum capacity of 300 MW, SMRs require less land and incorporate enhanced safety features.
• SMRs also have the potential to utilize low-enriched uranium, which India could import from the U.S. under the 123 Agreement.
• Expanding the role of SMRs in India’s energy mix would necessitate amendments to the Atomic Energy Act (1962) and related legislation to enable private sector involvement under the supervision of the Atomic Energy Regulatory Body (AERB), ensuring that both nuclear fuel and waste management adhere to international safeguards as directed by the Department of Atomic Energy (DAE).

Significance and challenges of Phase II:

• Stage II of India’s nuclear power program, represented by the Prototype Fast Breeder Reactor (PFBR) and its envisioned expansion with four more Fast Breeder Reactors (FBRs), each with a 600 MWe capacity, is aimed at enhancing the country’s nuclear power output.
• Challenges:
  • Renewables, such as solar energy, have become significantly cheaper, making nuclear power less competitive in terms of cost.
  • Public sentiment towards nuclear energy has shifted after the Fukushima Daiichi disaster in 2011.
  • The technical and operational complexities associated with FBRs.
  • The use of thorium in future reactors introduces complications due to the production of various radioactive isotopes, complicating waste handling and storage.
• Recommendations:
  • The International Atomic Energy Agency has recommended establishing an independent statutory regulator, leading to the proposal of the Nuclear Safety Regulatory Authority (NSRA) Bill.

Source: TH