This week, India’s three-phase nuclear power program passed a historic milestone. The indigenously designed and built 500 megawatt (MWe) Fast Electric Generating Reactor at Kalpakkam in Tamil Nadu reached criticality—the point at which the chain reaction of stable and controlled nuclear fission begins with sustained power output, marking the transition to the operational phase that would generate electricity. This marks India’s entry into the second of three phases of its nuclear programme.
The Department of Atomic Energy devised a three-phase program because although India has limited uranium reserves, it holds a quarter of the global thorium deposits that can be mined from monazite sands on the beaches of Kerala, Odisha and Tamil Nadu. In the first stage, natural uranium is used as fuel in pressurized heavy water reactors to generate power. The spent fuel from these reactors produces plutonium, the main fuel for the second stage, in which the fast-growing reactors generate more fuel than they consume. The prototype fast breeder reactor at Kalpakkam will produce Uranium-233 from thorium, laying the groundwork for the third stage, which will use the Uranium-233 bred in the second stage as fuel.
Today, nuclear power accounts for only 8.78 gigawatts of India’s total installed capacity of more than 520 GW. But experts predict a tripling of nuclear capacity to reach 22.38 GW by 2031-32. And thorium holds the key to that leap.
