On July 10, the Indian civilian nuclear program crossed another milestone with the second light water nuclear reactor (LWR) at Kudankulam going critical – the first stage in the production of electricity.
In what is termed a ‘first approach to criticality’, control rods that absorb neutrons were replaced with boric acid in primary coolant water and diluted gradually to increase the concentration of neutrons. As the number of neutrons in the 80-tonne uranium core reached an optimum, it set off a sustainable chain fission reaction that produced heat in a controlled manner.
In a press release issued by the Nuclear Power Corporation of India Ltd (NPCIL), R.S. Sundar, the site director of the Kudankulam Nuclear Power Project (KKNPP), noted that in the next step the reactor power will be increased in stages of 50%, 75%, 90% and 100% to generate the full capacity of 1,000 MWe, after each prior stage secures Atomic Energy Regulatory Board (AERB)’s approval. The plant is also expected to be synchronised to the southern grid in 30-45 days, when it would be generating 400 MWe of power.
While this is good news for the power-starved states in the south, the history of the first Kudankulam unit suggests there could be speed bumps on the road ahead. KK1, the newest LWR and the country’s biggest nuclear reactor at the time of its commissioning in 2013, has faced multiple technical challenges since then – reducing its overall efficiency and sparking off critical voices against Kudankulam again and again.
In terms of debate and controversy, the Kudankulam plant has been one of the most criticised infrastructure projects of our times. From its inception in a 1988 deal with the erstwhile USSR to its ongoing implementation, the journey has had significant political, diplomatic and scientific developments. Here’s a timeline.
November 1988 – Rajiv Gandhi and Mikhail Gorbachev sign an Intergovernmental Agreement to construct two pressurised light water reactors of the VVER (water-water energetic reactors) kind at Kudankulam. Under limited international nuclear commerce sanctions because of Pokhran-1 tests in 1974, India finds a lone friend in the USSR for its civilian nuclear programme.
April 1992 – The Nuclear Suppliers Group (NSG), founded in response to Pokhran-1, adopts new guidelines for transfer of nuclear supplies. It says importing states must be party to the Nuclear Non-proliferation Treaty (NPT), which India was (and is) not. In the light of NSG’s new guidelines and stiff opposition from its members, Russia finds it challenging to implement the 1988 agreement. Nonetheless, it ends up taking a pro-India stand, arguing that the deal doesn’t invoke the new requirements as it was struck prior to 1992, i.e., it gets ‘grandfathered’.
June 1998 – The project, which was in limbo for a long time due to the disintegration of the USSR, is revived after a supplementary agreement between NPCIL and Rosatom (Russia’s Federal Atomic Energy Agency). The agreement finalises the Russian VVER design and engineering supervision arrangements for the construction of the two reactors at Kudankulam. The nature of the agreement is not the usual turnkey one where the project is completed and handed over, but a partnership of technical nature in which Russians supply the designs, drawings and reactor equipment while Indians build the plant.
March 2002 – Construction of the KK1 and KK2 units begins. Date of completion is projected to be 2007. Anti-nuclear protests step up.
February 2008 – Another intergovernmental agreement is signed between Russia and India for joint construction of four additional plants at Kudankulam. But as this is signed post the NSG’s 1992 guidelines, India has to wait for the NSG to waive its guidelines.
September 2008 – NSG grants India a waiver.
September 2011 – In the aftermath of Fukushima, protests against the Kudankulam plant intensify. There is large outpouring of concern about the safety of the reactor in case of a tsunami like the one in 2004. Tamil Nadu’s Chief Minister Jayalalithaa orders suspension of all activities at the plant until people’s concerns are addressed. An expert committee is constituted by the state to look into the safety of the plant.
November 2011 – Former president A.P.J. Abdul Kalam visits the plant in his individual capacity and certifies the plant as safe. He proposes implementation of Kudankulam PURA (Providing Urban Amenities in Rural Areas), a scheme to build infrastructure and boost local economy, in order to win over locals.
March 2012 – In a significant U-turn propelled by acute power shortage in the state, Jayalalithaa gives consent to completion of the nuclear plant, claiming that the expert committee found the plant safe. She also announces a Rs 500 crore package for infrastructural development on the lines of Kalam’s recommendations. Both the units, 99% complete and 95% complete respectively by then, resume work.
July 2013 – KK1 goes live after successfully approaching first criticality, a full seven years beyond the expected deadline. NPCIL claims the same things as it did for KK2: that the plant would be connected to the grid in 30-45 days while generating 400 MWe and that the full scale operation would take place in stages.
October 2013 – KK1 is connected to the southern grid when generating only 160 MWe as opposed to the predicted 400 MWe. The reactor does not hold for long, tripping immediately and forcing a brief outage. It is restarted soon after.
April 2014 – Progress is achieved on the 2008 agreement to install additional capacity. India and Russia ink a deal to build the third and fourth units at Kudankulam at a projected cost of Rs 33,000 crore, expecting to start the project by 2016 after getting regulatory approvals from the AERB.
June 2014 – KK1 achieves full capacity generation of 1,000 MWe, becoming the single largest power generating unit in the country. The power generated is distributed between the southern states: Tamil Nadu gets 56%; Karnataka, 22%; Kerala, 13%; Andhra Pradesh, 5%; and Puducherry, 3%.
September 2014 – A year since its connection to the grid, the plant develops issues with the turbine and is closed down till December for inspection and maintenance. NPCIL reports this as a maintenance and repair drive before going into commercial operation.
December 2014 – Once reopened, the plant starts commercial operation on December 31.
January 2015 – Connection of the reactor to the electricity grid trips again, forcing shutdown of the plant.
May 2015 – There’s yet another shutdown because of “reactor trip due to transient in-steam generator level control.”
June 2015 – The reactor goes offline for ‘planned’ annual refuelling and maintenance. The expected date of reopening in October is not met due to a fault in one of the reactor’s coolant pumps being observed later. The delay in arrival of parts from Russia and the subsequent repairs pushes the restarting deadline.
Jan 2016 – KK1 finally opens after a seven-month halt.
Feb 2016 – Just three weeks after reopening, the reactor shuts down briefly due to a leak noticed in the conventional (non-radioactive) parts of the reactor. While the Department of Atomic Energy terms this long line of leaks, trips and outages in KK1 as “teething problems” in adapting to new technology, many critics attribute the repeated shutdowns to poor quality of components sourced and NPCIL’s incompetence in constructing the nuclear reactor.
February 2016 – Construction work begins for KK3 and KK4.
July 2016 – KK2 gets ready for commissioning after AERB’s approval for ‘first approach to criticality’. At 8:56 pm on July 10, the plant attained criticality and sustained fission, a whole decade behind schedule.