'Indian N-plants safe, located in less seismic zones'
The 20-odd nuclear power plants in India, with a generating capacity of 4,780 megawatt (Mw), are located at a much lower seismic area. “They are quite safe,” says the Nuclear Power Corporation (NPC), the state-run operator of the N-plants which is engaged in increasing the country’s nuclear capacity to 63,000 Mw by 2032.
In a quick analysis of India’s disaster preparedness against the backdrop of the explosion at the Fukushima nuclear power project following yesterday’s earthquake and tsunami, NPC said the reactors in India have been designed to withstand earthquakes. “All our plants are situated 300-2,000 km away from the tectonic Himalayan boundary”.
A G Chhatre, NPC’s associate director (stress analysis and seismology), told Business Standard, “If we look at the generation capacities (of N-plants) in various earthquake-prone regions of the world, they are categorised between Zones I and IX. Indian nuclear power plants are situated in Zone II, III and IV. Narora plant, which is the only plant situated in Zone IV, has experienced earthquake of 6.3 on the Richter scale, but it is working safely.” He said Zones VII, VIII and IX are highly seismic prone areas, while Zones II, III and IV are at a much lower seismic area. Japan’s nuclear plants are in Zones VII, VIII and IX, Taiwan’s are in VIII and IX.
| NPC ANALYSIS Location of existing nuclear plants in India | |
| Site | Seismic Zone |
| Tarapur | III |
| Rawatbhata | II |
| Kalpakkam | II |
| Narora | IV |
| Kakrapar | III |
| Kaiga | III |
| Kudankulam | II |
| Source: Nuclear Power Corporation | |
NPC’s joint director Shashikant Dharne said, nuclear plant structures, systems and equipment were designed and qualified for maximum possible earthquake at the location. This was amply demonstrated as Kakrapar plant kept operating during the devastating earthquake in Bhuj near Kutch on January 26, 2001. Narora has withstood several hundred tremors in the last two decades since its beginning of operation in 1989. “All nuclear power plants in the country have operated safely during earthquakes,” he emphasised.
Dharne further said: “All necessary precautions are taken during civil construction and equipment mounting to withstand earthquake tremors.
In Japan, the Fukushima reactors were shut down but it was not sufficient as special products kept generating heat which needed to be absorbed. For that, electricity was required to be drawn from the grid to circulate the coolant. In Japan the grid tripped after the earthquake and the tsunami and electricity was available only for a short time from emergency diesel generators. But they also tripped leading to explosion.” He added that in India multiple back-ups have been put in place to face such unusual turn of events. “Diesel generators of different capacities and makes have been placed at the nuclear plants to provide backup and additional safety systems installed. So ours is quite a different case and cannot be compared with Japan,” he said.