New Delhi: Prime Minister Narendra Modi on Monday congratulated both Indian and Russian atomic energy scientists after the second unit at Kudankulam achieved criticality last evening.
“Second reactor at Kudankulam became critical yesterday. This is a piece of great news, which makes us happy. I congratulate the atomic energy scientists, both from Indian and the Russian side for this major technological success,” tweeted the Prime Minister, who is presently in Kenya on the last leg of his four-nation tour to the African continent.
The second unit of Kudankulam Nuclear Power Project (KKNPP 2) attained first criticality at 8.56 p.m. on Sunday. It will add 1000 MWe electricity to the southern grid and raise the contribution of nuclear power in the country to 6780 MWe.
The process of First Approach to Criticality (FAC) was started on July 8 with the dilution of the boric acid in the primary coolant water and the neutron multiplication in the reactor core of the Unit 2, said Nuclear Power Corporation of India (NPCIL) Site Director R.S. Sundar in a statement.
KKNPP 2 is the 22nd nuclear power reactor in the country and India’s second Pressurised Water Reactor belonging to Light Water Reactor category. With this, now the KKNPP site holds a distinction for having two largest power reactors in the country.
The units of KKNPP in Kudankulam in Tamil Nadu’s Tirunelveli district are the Water-Water Energetic Reactor (VVER or WWER)-1000 type reactors setup with technical cooperation from the Russian Federation.
“The reactor was loaded with fuel assemblies containing about 80 tonnes of Uranium Oxide. Subsequently, a number of safety tests at the operating temperature and pressure were carried out successfully, ensuring the performance of various equipment as per the design intent,” he said.
“The first approach to criticality was undertaken after conforming to all the criteria for system performances as per the design requirements and after meeting all the stipulated statutory and regulatory requirements. After this, the unit has attained criticality smoothly. A team of the Atomic Energy Regulatory Board (AERB), NPCIL and Russian specialists is supervising the whole process,” he added.
“As a next step, reactor power will be increased in stages to generate 1000 MWe electricity as per laid down procedures and regulatory clearances. At the first stage the plant will be synchronised to the southern grid with about 400 MWe power within expected period of 30 to 45 days from the date of criticality,” said Sundar.
In the subsequent stages, after completion of procedural and regulatory requirements, power will be increased in steps of 50 percent, 75 percent, 90 percent and 100 percent.
The state-of-the-art KKNPP reactors incorporate enhanced safety features ensuring the highest level of safety in line with the current international standards. These are ‘Generation III+’ reactors incorporating a combination of active safety systems as well as passive safety systems like Passive Heat Removal System (PHRS), Hydrogen Recombiners, Core Catcher, Hydro Accumulators and Quick Boron Injection System (QBIS), he said.
This combination of multi-layered safety features ensures safety of the plant, public and environment.