It is indeed a good news for the energy managers of power-starved Tamil Nadu. Electricity will start cascading from the first unit of the Kudankulam Nuclear Power Project (KKNPP) by December. The mandatory pre-commissioning milestone event of loading of ‘dummy fuel assembly' into the reactor core of the first of the 2 X 1,000 MWe unit began on Friday.
“Since we've planned to complete the loading of dummy fuel assembly by mid-May and commence the loading of actual fuel of enriched uranium assemblies during September, we'll be in a position to commission the first reactor by December,” Chairman and Managing Director, Nuclear Power Corporation of India, Shreyans Kumar Jain told reporters at the KKNPP site. “About 50 per cent of the power generated by this reactor will be given to Tamil Nadu.”
A total of 163 dummy fuel assemblies, each 4.57 metres long and weighing about 705 kg, are being loaded into the reactor for full-scale thermo-hydraulic tests of the reactor systems, prior to the loading of actual fuel, to assess the design performance of the systems.
After being transported from the fuel storage building in special containers, which will also be used for transporting actual fuel assemblies, the dummy fuel assemblies are being loaded into the reactor core.
The re-fuelling machine for handling the actual fuel assemblies during the plant's operation has already been erected and commissioned. The machine has been calibrated with dummy fuel assemblies to validate its accuracy for safe operation with nuclear fuel.
After the design evaluation through hydro test and ‘Hot Circulation Flushing' of the primary coolant system, actual nuclear fuel will be loaded to eventually make the reactor critical, when controlled and self-sustained fission chain reaction is triggered to generate electricity.
Another significant milestone event of ‘rotation of the turbine generator rotor on barring gear' was achieved in January for the first unit. Sea water cooling systems, chiller plant, compressor plant and diesel generator plant have been commissioned successfully.
Meanwhile, the second unit has reached the advanced stage of construction as the tertiary dome for the passive heat removal system has been completed. The assembly of reactor pressure vessel is now in progress.
“Within the next three months, loading of dummy fuel assembly [actually removed from the first reactor] into the second reactor core will take place so that the second unit will start generating electricity six to eight months after the first reactor attains criticality,” Dr. Jain said.
Head, Atomstroyexport at KKNPP, Y.W. Dudkin, expressed immense satisfaction with the quality of construction of the 1,000 MWe reactors, for which this Russian firm provides technical support.