Nuclear power plant near Chennai all set for milestone event

Far removed from any protest-din, a nuclear power plant 40 km south of Chennai, is all set to achieving a milestone – loading of liquid sodium. The operators of the nuclear power station, which is half the size of the first unit of the Kudankulam nuclear power plant, are awaiting the green signal from the Atomic Energy Regulatory Board, the country’s nuclear power regulator. For the 500 MW ‘prototype fast breeding reactor’, loading of 1,750 tonnes of the coolant liquid sodium is practically the last big event before the unit starts generating electricity. This is an important milestone because nuclear establishments in all countries are watching India’s PFBR, the first plutonium-based fast breeder reactor anywhere in the world.

The Rs 5,677-crore techno-economic demonstration plant that a government of India-owned company is putting up is of crucial importance to the country’s nuclear plans. Its success would set the ball rolling for a clutch of ‘fast breeders reactors’—at least six of them have been planned. Two of the six would come right next door to the PFBR.

Fast breeder reactors are a big deal for Uranium-scarce India because they produce more nuclear fuel than they eat up. You blanket the ‘core’, where the fuel is simmering, with natural Uranium, the neutrons flying out of the core convert the Uranium into Plutonium – a valuable fuel. You blanket it with Thorium, you end up with Uranium – 233, a variety of Uranium that has split-able atoms. (Heat is produced when the atoms’ nuclei are split by a runaway neutron, and the heat is converted into electricity.) The PFBR will have a blanket of a mixture of natural Uranium and Thorium, so apart from electricity, you also get nuclear fuels. India has a fourth of all the Thorium discovered on this planet, so it is wise to use it gainfully. Problem is, Thorium is useless as a fuel, until it is converted into Uranium-233, for which you need fast breeder reactors.

Then why didn’t India start building fast breeders right from the beginning? Because it is not possible.

The fast breeders need a lot of Uranium, or Plutonium. Uranium, India does not have much of, and no other country would give us after 1974, when Pokhran-I happened. Plutonium does not occur in nature, it has to be produced in a nuclear reactor. So, the country had to wait for four decades to have sufficient stock of Plutonium to fire up the fast breeders. And now, it is happening. Asked when would the PFBR start producing electricity, a senior official of Bharatiya Nabhikiya Vidyut Nigam Ltd, which is putting up the plant, said that it would be technically possible to do that in 4-5 months after the liquid sodium loading happens. But then, the schedule would entirely depend upon the regulator, AERB. And the Board could hardly be expected to rush through matters—it would want every step checked out multiple times to satisfy itself over safety. But a little delay would not matter here—after all, it is still a prototype, and in any case it is already well over the planned six years since the construction began in 2004.

Source: Business Line