83 MW pressurised light-water reactor with enriched uranium fuel of INS Arihant & Arighaat

The Bhabha Atomic Research Centre (BARC) is set to play a pivotal role in powering India's future nuclear submarines through the development of a new 190-MW nuclear reactor. This initiative is part of India's broader strategy to enhance its naval capabilities, particularly in response to evolving geopolitical dynamics in the Indo-Pacific region.

What Are The Key Features of The New 190-MW Nuclear Reactor Developed By BARC

The new reactor is specifically designed for upcoming classes of submarines, including the P77 nuclear attack submarines (SSNs) and the S-5 ballistic missile submarines (SSBNs). This marks a significant advancement from the current fleet, which utilizes an 83-MW pressurized light-water reactor. The enhanced power output of the new reactor will allow submarines to operate more efficiently and for extended periods without surfacing, thereby improving stealth and operational capabilities.

The new 190-MW nuclear reactor that will significantly enhance India's naval capabilities, particularly for its future nuclear submarines, including the P77 nuclear attack submarines (SSNs) and S-5 ballistic missile submarines (SSBNs).

Key Features of the 190-MW Nuclear Reactor

Increased Power Output

The 190-MW reactor represents a substantial upgrade from the existing 83-MW reactors used in the Arihant-class submarines. This increased power output will enable submarines to operate more efficiently and for longer periods without surfacing, enhancing their stealth and operational capabilities.

Dual Configuration

 The reactor will be designed in a twin configuration, allowing it to provide sufficient power for larger vessels, such as a potential future nuclear aircraft carrier weighing around 70,000 tons. This approach not only meets the needs of submarines but also lays groundwork for future naval projects.

Variants For Different Missions: The Reactor Design Includes Two Key Variants:

Tailored for nuclear attack submarines (SSN), this variant can handle dynamic power demands necessary for rapid manoeuvres and operational flexibility.

Designed for endurance missions (SSBN), this variant focuses on maintaining steady power output for long-duration stealth operations.

Advanced Technology And Safety Features

Building on the technology demonstrated by the Arihant-class reactors, the new design is expected to incorporate advanced safety features, improved fuel efficiency, and reduced maintenance requirements. This ensures that the reactors can withstand harsh underwater environments while remaining safe and sustainable for extended missions.

Indigenous Development

The development of this reactor marks a significant step towards self-reliance in India's defence technology. By creating an indigenous nuclear reactor, India aims to reduce dependence on foreign technology and enhance its strategic capabilities amid rising regional tensions.

Operational Flexibility

The reactor's design allows for quick adjustments in power output, which is crucial for SSNs that require rapid changes in speed and depth during operations. This operational flexibility is essential for effective naval warfare.

The development of this reactor is of strategic importance and crucial for several reasons. The initiative reflects India's commitment to self-sufficiency in defence technology, reducing reliance on foreign technology and expertise. BARC has been instrumental in developing indigenous nuclear capabilities since its inception in 1954.

By equipping submarines with more powerful reactors, India aims to bolster its second-strike capability. This capability is essential for maintaining and enhancing a credible deterrent posture, particularly given India's no-first-use nuclear policy. The ability to launch retaliatory strikes from submerged platforms significantly enhances national security.

The urgency for advanced nuclear submarines has intensified due to strategic shifts in the Indo-Pacific region and challenges posed by neighbouring adversary countries. The new reactor will support the construction of advanced submarines that can carry more sophisticated missile systems, such as the K-4 ballistic missile with a range of up to 3,500 km.

Future Submarine Programs

India's future nuclear submarine programs are poised for significant expansion and modernization, driven by strategic imperatives in the face of rising regional threats, particularly from China. India's submarine fleet is undergoing significant expansion with the addition of several new vessels:

INS Arihant and INS Arighat: India has already commissioned its first two nuclear-powered ballistic missile submarines (SSBNs), INS Arihant and INS Arighat. The latter was commissioned in August 2024 and is equipped to carry K-4 ballistic missiles with a range of 3,500 kilometers. The third SSBN, INS Aridhaman, is expected to be commissioned in early 2025, further enhancing India's sea-based nuclear deterrence capabilities.

Project 75: This ongoing project aims to construct six indigenous nuclear-powered attack submarines (SSNs). The Indian government recently approved plans to build two SSNs under Project 77, with a total estimated cost of ₹40,000 crore (approximately $5 billion). These submarines will be designed for conventional warfare and are expected to take about 10-12 years to complete.

In an Expansion bid of the SSBN fleet, India plans to build a total of four Arihant-class SSBNs and at least two more advanced S-5 class submarines. The S-5 class will feature improved capabilities, including a larger payload capacity for ballistic missiles.

Approximately 95% of the components for the new SSNs will be sourced domestically, reflecting India's commitment to self-reliance in defence manufacturing. This move aligns with broader national objectives to enhance indigenous defence capabilities while reducing dependence on foreign technology.

The establishment of specialized facilities, such as the very-low-frequency (VLF) communication station at Vikarabad, is essential for maintaining secure communications with deployed submarines. Additionally, the new submarine base at INS Varsha in the Bay of Bengal will provide strategic advantages during operations against potential adversaries.

BARC's initiative to develop a 190-MW nuclear reactor for India's future submarines is a strategic move that enhances India's naval capabilities while promoting self-reliance in defence technology. As India continues to navigate complex security challenges, these advancements are expected to play a vital role in ensuring national and regional stability.