The reactor designed for a long fuelling cycle time is capable of remaining under water for an extended period, the sortie time being essentially dictated by the endurance of the crew.

The land-based version kept here was conceived and built as a technology demonstrator for the compact pressurised water reactor with a load following capability.

Also known as 'half boat', the entire propulsion plant with primary, secondary, electrical and propulsion systems along with its integrated control was packed in the aft end of the land-based submarine hull designed and built specifically for this purpose.

While in sea the reactor supplies super-heated steam to the propulsion plant to run the submarine, at the PRP Centre the propulsion power is absorbed in the dynamometer which in turn is cooled by sea water.

Banerjee said major components of the submarine reactor were made by domestic industries.

'The reactor vessel is made of special grade steel by Heavy Engineering Corporation, Ranchi, steam generator by Bharat Heavy Electricals Limited (BHEL), pressure valves were made by Audco India, Chennai, and others,' he added.

New materials of construction and new technologies were used in building the reactor. The uranium enriched metallic fuel is new too.

There are around 13 fuel assemblies with each assembly having 348 fuel pins.

'It is not just building a nuclear reactor to power a submarine. For us, it is capacity building in the country to get into high technology areas,' said AEC chairman Anil Kakodkar.

PRP facility director Sekhar Basu said the centre will now be the training ground for personnel planning to operate reactors in submarines apart from carrying out research activities.