Ready to run

With the first unit of the Kudankulam Nuclear Power Project reaching criticality on July 13, a project that was envisaged some 25 years ago draws close to fruition.

Published : Jul 24, 2013 12:30 IST

The Kudankulam Nuclear Power project, a file picture. At left is the first unit that went critical on July 13.

The Kudankulam Nuclear Power project, a file picture. At left is the first unit that went critical on July 13.

IT was no empty boast. “We want to show the world we can deliver.” When the late S.K. Agrawal spoke these words on March 13, 2004, he was Project Director of the Kudankulam Nuclear Power Project (KKNPP) in Tamil Nadu. He obviously knew his mind and what Indian nuclear engineers were capable of. It was indeed a great day for Nuclear Power Corporation of India Limited’s (NPCIL) engineers and staff when the KKNPP’s first unit, with a capacity of 1,000 MWe, went critical at 11-05 p.m. on July 13 and applause erupted in the reactor’s state-of-the-art control room.

The much-awaited but long-delayed event demonstrated that India had come of age in a high technology area—that it could not only absorb the Light Water Reactor (LWR) technology from Russia but build LWRs on its own. At 1,000 MWe, KKNPP-1 has the distinction of being the largest single power generating unit in the country. The second unit at Kudankulam, also with a capacity of 1,000 MWe, is all set to reach criticality in eight months from now.

Today, the KKNPP, with its two Russian VVER-1000 units, stands as the model of ideal cooperation between India and Russia. But though the Russians supplied the designs, drawings and all the equipment for the two identical reactors, the NPCIL built them. In the process, the NPCIL had to contend with a new technology, that of LWRs. The sheer size of everything about the two reactors did not deter the NPCIL from insisting in 1998 that its engineers would build the two reactors when a supplementary agreement to the earlier Inter-Governmental Agreement of 1988 was signed on the Kudankulam project.

Massive civil structures and huge mechanical contraptions greet you everywhere at Kudankulam. The reactor building is 80 metres tall. Three hundred pillars support the turbine hall. The reactor pressure vessel (RPV), which forms the heart of a nuclear power plant, weighs 316 tonnes. Made of stainless steel, it is 19.5 metres tall and has a diameter of 4.5 metres. The turbine-generator weighs 380 tonnes. The core-catcher, into which the molten fuel core will drop in the unlikely scenario of an extreme accident, is a huge vessel that weighs 101 tonnes. A mini-port has been built at the Kudankulam site for unloading the massive equipment from Russia by erecting a dyke that needed 30 lakh tonnes of rock in the waters of Gulf of Mannar. Two caissons, concrete structures each weighing 2,500 tonnes, float in the sea.

R.K. Sinha, Chairman, Atomic Energy Commission (AEC), could not hide his joy when the first unit went critical. He told Frontline : “Our nuclear power programme has reached an important milestone today. I am glad and I feel very proud.” Sinha, who is also Secretary, Department of Atomic Energy (DAE), called the Russian VVER-1000 units ”technically perfect” and “among the safest reactors in the world”.

On how he felt on the occasion because the KKNPP had a chequered history and had to fight a long, hard and many-sided battle before the first unit was started up, K.C. Purohit, Chairman and Managing Director, NPCIL, said, “Your feeling is the same as mine. They synchronise.” The next couple of weeks will see the reactor operators performing experiments on the physics of the reactor. After that they will step up the reactor power in stages. “We will generate 400 MWe in 30 to 45 days and the plant will be synchronised with the southern grid. In subsequent stages, after completing the procedural and regulatory requirements, power will be increased in steps of 50 per cent, 75 per cent, 90 per cent and 100 per cent power,” Purohit said.

M.K. Balaji, Executive Director (Operations, Light Water Reactors), NPCIL, was thrilled. “We said we would build the reactors, commission them and operate them. We have done it. We have also assimilated the technology of LWRs,” he said. The first unit reaching criticality was “a joyous occasion” because it could generate power in a safe and sustained manner and bridge the energy gap in the country, he said. Normally, nuclear power reactors were imported on the basis of a turnkey agreement, but India insisted that the Kudankulam project would be based on a technical agreement. That is, while the Russians would provide the drawings, designs and all the equipment, India would build the reactors. “We told ourselves that the best way to learn and go forward was to build the reactors ourselves. Today, the KKNPP is a symbol of self-reliance and marshalling of the LWR technology,” said Balaji, who was earlier Site Director, KKNPP. He described his participation in the construction of the reactors as “a life-time experience” and said he would “cherish this experience forever”.

“All parameters are normal,” said R.S. Sundar, Site Director, KKNPP-1 and 2. “After a long time, the mood here is good.” He called the event a “historic milestone because we have overcome so many obstacles”. The huge Indian and Russian workforce at the site was happy that its hard work had had a positive outcome.

V. Rybkin, a Russian who works as an interpreter, said: “The purpose of our stay here and one of our objectives is to put the project in operation. We have now reached that goal. This was expected because of the great and fruitful cooperation between Russia and India. We are friends. We are brothers.”

On July 17, the reactor operators were busy with reactor physics experiments, which would be followed by a small break. The NPCIL engineers were preparing for “the next step of power rating” of the reactor and synchronisation with the electricity grid, Sundar said.

On July 14, the day after the first reactor reached criticality, the mood was sombre at Idinthakarai, a few kilometres from Kudankulam, which has become the arena of a sustained agitation for two years now against the Kudankulam project. R. Meldred, P. Sundari, P. Sellammal or Leela Visuvasam, all taking part in a daily fast in the forecourt of St. Lourde’s Church at Idinthakarai, were incredulous that the first unit had been started up. They declined to accept the fact that the reactor had gone critical the previous day. All the women participants in the fast dismissed any suggestion on the commissioning of the reactor as propaganda. “The nuclear power plant officials want to instigate us by claiming that they have started the unit. For the past two years, V. Narayanasamy [Minister of State in the Prime Minister’s Office] has been claiming periodically that the unit will be commissioned,” Sundari said. Meldred declared, “We will continue to fight in a dharmic way against the demon of nuclear power.”

S.P. Udayakumar, coordinator, People’s Movement Against Nuclear Energy (PMANE), which has been spearheading the agitation against the KKNPP at Idinthakarai, Uvari, Vijayapathi and other neighbouring villages, said that the “non-violent non-cooperation with this evil of nuclear power will continue”.

N. Nagaich, Executive Director (corporate planning and corporate communications), NPCIL, called the first unit at Kudankulam “the harbinger of the large-size LWR technology in India”. It is the 21st nuclear power reactor in India and the country’s first Pressurised Water Reactor (PWR) belonging to the LWR category. The installed total capacity of these 21 reactors is 5,780 MWe. However, only 20 reactors are operational because the first unit (100 MWe) at Rawatbhatta in Rajasthan has been shut down permanently. The 20 operational reactors have a total capacity of 5,680 MWe.

The VVER-1000 units are located in Radhapuram taluk in Tirunelveli district. They have come up on the shore of the Gulf of Mannar in the Bay of Bengal. They use enriched uranium as fuel and light water as both coolant and moderator. According to Nagaich, there are 55 VVER units operational across the world, and of them 25 are VVER-1000 that generate 1,000 MWe each. The VVER-1000 units have a lineage, having evolved over the years, incorporating advanced active and safety features. They have evolved from variants such as V-187, V-338, V-320, V-413, V-392 and V-428. Of these, V-392 has the most advanced design features and it is this design that the VVER-1000 units have adopted.

Out of 2,000 MWe to be generated from the two reactors at Kudankulam, Tamil Nadu’s share will be 925 MWe. Karnataka will receive 442 MWe, Kerala 266 MWe, Puducherry 67 MWe and the unallocated share will be 300 MWe. The NPCIL will sell the electricity generated from the Kudankulam reactors to the State utilities at Rs.2.50 a unit.

While the original cost of the two units was Rs.13,171 crore, the revised cost is Rs.17,270 crore. Russia had advanced a credit of Rs.6,416 crore to both the units.

With the first unit having been started up, all eyes are now on the second unit. As on July 16, 100 dummy fuel assemblies out of a total of 163 have already been loaded into this unit’s reactor core. The loading of dummy fuel bundles into a reactor marks the commencement of the process of its reaching criticality. Balaji said, “Dummy fuel assemblies are loaded into the reactor for conducting full-scale thermo-hydraulic tests of the reactor systems, prior to the loading of the actual fuel, to assess the design performance of the design systems.” The dummy fuel assemblies are made of lead instead of uranium, each bundle weighing 705 kg. The dummy fuel assemblies are a replica of the actual nuclear fuel assemblies, both in dimension and in weight. Each assembly has a length of 4.57 metres.

Perhaps no other nuclear power project has alternated between hope and despair as much as the Kudankulam project, which has been buffeted by legal battles and sustained agitations. Prime Minister Rajiv Gandhi and Soviet President Mikhail Gorbachev signed the Inter-Governmental Agreement (IGA) in November 20, 1988, on setting up the KKNPP. But soon the project was as dead as a doornail with the Soviet Union disintegrating and differences cropping up between India and Russia over the rupee-rouble repayment ratio. A despondent M.R. Srinivasan, who was AEC Chairman from 1987 to 1990, called it “a non-starter”.

The project, however, erupted into life when, on June 21, 1998, a supplementary agreement to the earlier IGA was signed in New Delhi by Russian Minister for Atomic Energy Yevgeny Adamov and AEC Chairman R. Chidambaram. That Russia stuck its neck out to sign this agreement within a month of India conducting five nuclear tests in May 1998 and becoming an international outcast showed how much Russia valued its friendship with India.

The Kudankulam project began with the first pour of the concrete taking place on March 31, 2002. It raced ahead of schedule by several months during the next four years and a confident NPCIL predicted that the first unit would be started up in March 2007 instead of the targeted December 2007.

When S.K. Jain took over as CMD, NPCIL, in January 2004, the project was six months ahead of schedule in construction activities. On March 30, 2004, he said: “For the Russian Federation, the schedule is to be completed in 67 months, that is, five years and six months. But we are making all serious efforts to see that the first unit reaches criticality in five years [from the first pour of the concrete, that is, March 2007]. So far, things have moved towards the target. The project team at Kudankulam is highly motivated” ( Frontline , April 23, 2004).

But delays in the supply of designs, drawings and equipment by the Russians decelerated the project’s further progress, and the project fell behind schedule by a couple of years. The sustained agitation by the PMANE from September 2011 added to the KKNPP’s troubles. Fishermen and other residents of the neighbouring villages held the plant hostage for several months by blocking the entry of NPCIL employees.

PMANE representatives erected a marquee near the plant’s main gate and insisted that they would not allow more than 50 workers a shift to man the reactors’ equipment, whereas it needed several hundred workers. This went on from September 2011 to March 2012.

What puzzled the Centre and NPCIL officials was that this agitation broke out in September 2011 when the first unit was all set for criticality in December 2011.

Leaders of the PMANE claimed that their limiting the number of workers who could work in a shift was in adherence to the State Cabinet’s resolution of September 22, 2011, which urged the Centre and Prime Minister Manmohan Singh to halt the work on the project until the people’s fears about the project’s safety were addressed. The KKNPP was back on the rails after the State Cabinet, headed by Chief Minister Jayalalithaa, met on March 19, 2012, and in a reversal of its September 22, 2011, resolution adopted a resolution for the early commissioning of the KKNPP.

What forced the State government’s hand was the fact that Tamil Nadu was suffering from a debilitating power cut of more than 12 hours a day—it was facing a shortfall of 4,000 MW. There were protests all over Tamil Nadu against the State government’s handling of the power crisis. By March 2012, the project was behind schedule by five years.

On September 13, 2012, the Supreme Court declined to stay the loading of the fuel into the [first] reactor but agreed to examine the risk associated with the project in view of the safety of the people living around the plant. The court was hearing an appeal by the social activist G. Sundararajan against the Madras High Court’s decision declining to impose any restraint on the project.

The apex court threw out the appeal on May 6, 2013, and allowed the commissioning of the reactor, subject to conditions. The Bench said, “We have to balance ‘economic, scientific benefits’ with that of ‘minor radiological detriments’.” It was part of the national policy to develop, control and use atomic energy for the welfare of the people and economic growth, the judges said. Justices K.S. Radhakrishnan and Dipak Misra, in concurring judgments, listed 15 conditions to be followed before the plant could be commissioned. One of them was that the plant should not be made operational unless the Atomic Energy Regulatory Board (AERB), the NPCIL and the DAE accorded final clearance after ensuring the quality of various components and systems because their reliability was of vital importance. Another direction wanted the AERB, the NPCIL, the Union Ministry of Environment and Forests (MoEF) and the Tamil Nadu Pollution Control Board (TNPCB) to “oversee each and every aspect of the matter including the safety of the plant, the impact on environment, the quality of components and systems in the plant before the commissioning of the plant”. A report to that effect should be filed before the Supreme Court before the plant’s commissioning, the order said.

The AERB, the NPCIL, the MoEF and the DAE duly submitted their reports to the Supreme Court, certifying the safety of the systems and the quality of the components used. Several hours before the first unit went critical, Sinha told Frontline : “The plant has been technically ready for the past two weeks.” The NPCIL received a formal communication from the MoEF on the evening of July 11 saying that the ministry too had submitted its report to the Supreme Court. “Thereafter, within four hours, on the receipt of the permission granted by the CMD, NPCIL, the process of approach to criticality was started at 11.49 p.m. on July 11 and the process is expected to take 48 hours to 72 hours,” the AEC Chairman said.

Nagaich explained the role of the dilution of borons during the reactor’s approach to criticality. Boron (a neutron absorber) is used in the form of boric acid solution in the primary coolant water to keep the nuclear reactor in a sub-critical state before it attains criticality.

“The process of approach to criticality involves gradual dilution of boron, which allows the neutrons in the nuclear fuel mix matrix to multiply till a controlled self-sustaining nuclear fission reaction is attained in the reactor,” Nagaich added.

Data on the concentration of boron in the primary coolant water were gathered with the help of 33 online detectors, and sampling was done with the measurements carried out by special instruments. The count of neutrons was done using special neutron detectors. As was expected, based on the reactor physics calculations, the trend of multiplication of neutrons was observed on the afternoon of July 13. Sinha predicted, “On the basis of the current trend, which is in line with the projections already made, it is expected that criticality will be achieved by about midnight.”

A specialised group of Indian physicists and experts from the Kurchatov Institute at Moscow, which is a leading research and development organisation in nuclear energy, monitored the process of criticality. An AERB observer team was present. Purohit said, “In a well-knit and organised manner, everything has been going on as per the procedures laid down. We expect the process to continue and we will be able to achieve criticality around midnight.”

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