Mumbai: On July 23, 2025, Naval Group and Mazagon Dock Shipbuilders Limited (MDL) formally entered into a collaboration agreement for the integration of indigenous energy system plugs, developed by DRDO, onboard the Indian Navy’s Kalvari-class submarines, built entirely by MDL based on successful transfer of technology from Naval Group for its Scorpène® submarine.
This agreement follows the contract signed on December 30 2024, between the Indian Ministry of Defence and
MDL, for the construction and integration of this indigenous propulsion design. Under this agreement, the submarines will undergo a complex process known as “Jumboisation,” involving precision cutting of the hull, safe insertion of the plug, and re-joining of the structure to have a fully operational and safe submarine. As the original equipment manufacturer (OEM) of the Scorpène® submarines, Naval Group will provide technical oversight, proprietary materials, and specialised training to experienced Indian engineers of MDL to ensure seamless integration.
This project, reflects the commitment of MDL and Naval Group in supporting India’s vision of self-reliance in defence manufacturing, contributing significantly to the ‘Aatmanirbhar Bharat’ initiative, with the incorporation of indigenous technologies developed by DRDO into the Kalvari class submarines. This cooperation between the major shipyards is epitome for further strengthening the long-standing defence partnership between France and India, built on mutual trust, technological collaboration, and shared strategic objectives.
Speaking on the occasion, Laurent Espinasse, Executive Vice President of Submarine division at Naval Group, said, “We are honoured to deepen our partnership with MDL and DRDO. The integration of indigenous energy system into the Kalvari-class submarines is a major step forward in our shared journey toward technological and operational advancements. Naval Group is proud of its long-lasting collaboration with the Indian navy, industry and stakeholder, in “walking the talk” by working together in integrating key indigenous technologies into Scorpène® submarines, fully built in India.”
During the kick-off meeting for the project, Cmde S B Jamgaonkar, IN (Retd), Director Submarines and Heavy Engineering division at MDL, said, “As a ‘Shipbuilders to Nation’ and the only defence PSU to construct submarines in India, we are honoured to work towards enhancing the operational capability of the Indian Navy’s submarine fleet. We are pleased to extend our natural partnership with Naval Group and we shall jointly work towards successful integration of the DRDO developed propulsion system with the P75 Project Scorpene submarines. Mazagon Dock Shipbuilders Ltd remain fully committed to delivering this project with the highest standards of quality, precision and within the Project timelines.”
