The Defence Research and Development Organisation (DRDO) in India recently administered the last developmental examination of the Air Independent Propulsion (AIP) System, a key advancement for diesel-electric submarines.
About the Air Independent Propulsion (AIP) System
Submarines generally belong to two categories: conventional and nuclear. Conventional submarines employ diesel-electric engines, necessitating surfacing to gather atmospheric oxygen almost daily for fuel combustion. The integration of an AIP system allows a submarine to acquire oxygen just once weekly.
This self-designed AIP is a significant endeavor of Naval Materials Research Laboratory (NMRL), part of DRDO, specifically aimed at enhancing the Navy’s capabilities. The project aspires to incorporate this technology into India’s Scorpene class submarine INS Kalvari by 2023.
Advantages of Implementing an AIP System
With the AIP system, submarines need not surface as frequently, significantly amplifying their stealth and lethal qualities. Ordinarily, diesel-electric submarines must surface regularly to replenish their batteries, thus limiting their undersea endurance period. The ‘air-independent’ propulsion technology lowers the diesel generat usage on surface air.
While various types of AIP systems are being developed globally, NMRL’s fuel cell-based AIP is distinctive because of its onboard hydrogen generation.
Fuel Cell Based AIP System Explored
A fuel cell-based AIP system operates through an electrolytic fuel cell that releases energy by combining hydrogen and oxygen, leaving water as the sole waste product, resulting in minimal marine pollution. These cells boast high efficiency without any moving parts, which ensures low acoustic emissions from the submarine, thereby maintaining its stealth capabilities.
About the Naval Materials Research Laboratory
The NMRL is a DRDO laboratory conducting basic research and practical technology development across areas such as Metallurgy, Polymer, Ceramics, Coating, Corrosion and Electrochemical Protection, Marine Biotechnology, and Environmental Sciences. The laboratory’s mission includes the development of AIP systems for naval submarines and fuel cell technologies, providing scientific solutions for all Indian Navy material categories, and undertaking strategic research projects.
Comparing Nuclear Submarines and Conventional Submarines
The primary contrast between conventional and nuclear submarines lies in their power generation system. Nuclear submarines, like INS Arihant and INS Akula, utilize nuclear reactors, while conventional ones, like Project-75 and Project-75I Class Submarines, use diesel-electric engines.
While nuclear-powered submarines are considered crucial for deep-sea operations, conventional diesel-electric ones are indispensable for coastal defense and operations nearshore.
