Kudankulam 1 cleared for criticality

Friday, 12 July 2013

UPDATED: The box noting achievement of criticality was added to this story on 15 July.

The two-year delay in commissioning India's new reactors at Kudankulam may soon be over now that operators have been authorised to 'approach first criticality' at unit 1.

Permission to commence chain reaction in the reactor core and begin a program of low-power tests was granted by the Atomic Energy Regulatory Board (AERB) on 11 July. It marks the next stage of a commissioning program that in several weeks' time, and with separate permission, should culminate in the reactor raised gradually to full power and subsequently handed over to owner Nuclear Power Corporation of India Ltd for commercial operation.

Criticality achieved

A two day process to reach criticality was started late on 11 July, achieving self-sustained chain reaction at 11.05pm on 13 July, according to Nuclear Power Corporation of India Ltd.

The unit is one of two VVER-1000 pressurized water reactors built as part of an bilateral agreement between India and Russia signed back in 1988. Construction began in 2002.

Yesterday's permission to start the first reactor, even at low power, is an important milestone for the unit, which was completed in March 2011. Shortly afterwards came the accident at Fukushima Daiichi, and with encouragement from foreign activists a powerful opposition movement emerged among local people. This saw one protestor killed, engineers blocked from the site for weeks, and all levels of government increasingly drawn into the legal battles over the justification of the project.

Eventually in May this year a panel of two Supreme Court judges declared their opinion that "there is need for nuclear energy for the welfare of the public and for the welfare of the people of India." They stressed that "apprehension expressed by some sections of the public... has no basis." They recommended that criminal charges against certain protestors be dropped, "so that peace and normalcy be restored at Kudankulam."

The court also underlined that the proper regulatory safety procedures must be followed, and the AERB noted that it is observing this direction. Some performance issues were identified with a number of pumps in the passive core cooling system in April and these have been replaced.

When both units are in operation the power plant will supply 1900 MWe to the southern state of Tamil Nadu, including the major port of Tuticorin, 100 kilometres away.

Researched and written
by World Nuclear News