Kudankulam Nuclear Power Plant, Tamil Nadu, India
The Kudankulam Nuclear Power Plant (KNPP) is under construction 650km south of Chennai, in the Tirunelveli district of Tamil Nadu, India. The project is being developed by the Nuclear Power Corporation of India (NPCIL).
Two 1,000MW pressurised water reactor (PWR) units based on Russian technology are being erected in phase one of the project. The plant is also scheduled to be added with four more PWRs as per the agreement signed between India and Russia in December 2008.
Atomstroyexport, a subsidiary of the Russian State Nuclear Energy Corporation Rosatom, is the supplier of equipment and fuels for the nuclear power project.
Kudankulam nuclear power plant construction and protests
Concrete work for units one and two of the KNPP started in March 2002 and July 2002 respectively. NPCIL expects to start commercial operations from unit one and unit two of the NPP in 2013 and 2014 respectively.
The construction works at the project site were stopped in October 2011 due to blockage by protestors. The project works resumed in March 2012 with the permission of the Tamil Nadu Government.
In May 2013, the Indian Supreme Court dismissed the petitions by nuclear activists questioning the safety of the nuclear power plant and granted the go-ahead for the commissioning of the first two units.
However the Atomic Energy Regulatory Board (AERB), NPCIL and the Department of Atomic Energy of India have been asked by the court to ensure the safety of the plant and give final clearances before the start of commercial operation.
Controversy over KNPP
Kudankulam NPP has been a controversial project since its inception, with protests by local residents and various activist groups over potential radiation threat and issues related to nuclear waste disposal by the plant.
The anti-Kudankulam campaign got intensified with Fukushima nuclear incident in Japan following the earthquake and tsunami there in 2011.
It was alleged that KNPP is located in a tsunami prone area and more than one million people residing within the 30km radius of the nuclear power plant cannot be evacuated safely in the occurrence of any nuclear disaster.
The People's Movement Against Nuclear Energy (PMANE) is at the fore front of the anti-Kudankulam campaign.
The identification of four faulty crucial valves in reactors at Kudankulam and the arrest of a few Russian officials for sourcing substandard materials for the nuclear equipments further fuelled the opposition to the KNPP.
Kudankulam nuclear power plant details
NPCIL and Rosatom finalised the reactor design and engineering supervision arrangements for the construction of the KNPP phase one in 1998.
Construction of the INR 140bn ($2.47bn) phase one of the Kudankulam nuclear project started in 2001. The first two units of the NPP were originally scheduled for commissioning in December 2007 and December 2008 respectively.
The project has, however, experienced significant time-overrun due to persistent agitation and protests by locals and nuclear activists over safety concerns. The timeline for commissioning the project has been extended many a time.
Kudankulam NPP will have a production life of 60 years, which is extendable by another 20 years. The plant is expected to supply power at a cheaper rate of about INR 2.50 per unit.
The home state Tamil Nadu is allocated 50% (925MW) of the power generated from KNPP. The neighbouring states will share 35% of the residual power, including 442MW for Karnataka, 266MW for Kerala and 67MW for Puducherry. The other 15% of the generated power will remain unallocated and be added to the central pool.
Reactor at India's KNPP
Kudankulam (or Koodankulam) is India's first nuclear plant to use imported PWR technology. The existing nuclear power plants in India use pressurised heavy water reactor (PHWR) technology or boiling water reactor (BWR) technology.
The plant uses the advanced version of Russian-developed PWR nuclear technology called VVER. VVER stands for Vodo-Vodyanoi Energetichesky Reactor, which means Water-Water Power Reactor. The VVER technology has completed more than 1,500 reactor-years of operating time.
The KNPP is installed with AES-92 (or V-466 model), the latest version of the third generation VVER-1000, that offers greater safety and longer lifespan.
Safety features at Tamil Nadu's nuclear facility
The AES-92 design features a combination of active and passive safety solutions. It retains the traditional active safety provisions, such as the use of neutron absorbing control rods to control the reactivity.
The passive safety system incorporated in the design relies on natural factors, such as pressure differentials, gravity or natural convection to ensure protection against malfunction of the reactor during emergency situations.
The passive safety facilities of the AES-92 reactor system include the fast injection of high pressure boron, provision of extra tanks for long-term supply of borated water to the reactor in a passive way, and the system for inter-containment area passive filtration.
The reactor building is provided with a series of passive hydrogen re-combiners to convert abnormal production of hydrogen into water. The design also includes a system for containing the molten-core of the reactor during severe accident.
The AES-92 type reactor has a double protective containment with the inner envelope made of steel and the outer one made of heavy reinforced concrete steel, to prevent radioactive release into the environment during possible disasters including earthquakes, a tornado or aircraft crash. The inner containment is equipped with a water sprayer system to ease the steam pressure in the reactor.
Contractors involved with the Indian nuclear power station
Atomstroyexport is responsible for the technical design, construction supervision, technical support for reactor commissioning, as well as for training the operation and maintenance staff of the plant. It is also responsible for supplying the equipment and materials for the NPP.
Bharat Heavy Electricals is responsible for setting up the machines at the plant. NPCIL takes care of construction, erection and commissioning of the plant.
Commercial operation of a 192MW run-of-the-river Allian Duhangan hydroelectric power plant began in April 2010.
The Rajasthan Atomic Power Project (RAPP), located in Rawatbhata in the north Indian state of Rajasthan, currently has six pressurised heavy water reactor (PHWR) units operating with a total installed capacity of 1,180MW.