Until 1917, it seemed implausible to break the unbreakable tiniest particle called “atom”. But a British physicist, Ernest Rutherford made a breakthrough that led the world to use nuclear technology for many goods. Through a scientific research he proved that splitting of atoms was just possible. Thereafter, nuclear science expanded by leaps and bounds over the years: James Chadwick discovered neutron in 1932; Enrico Fermi researched on bombarding uranium with neutrons in 1934; and Otto Hahn and his colleagues split the nucleus of uranium in 1939. A sustained fission process has been demonstrated in the world’s first nuclear power reactor “Chicago Pile-1” in 1942. Since then, the world paced ahead in nuclear technology and it began to turn the invisible nuclear energy into most useful electrical energy. And today there are about 460 nuclear power reactors in operation worldwide which accounts for about 11% of the global power generation.
Asia’s first nuclear power plant
Almost three decades later uranium atom was first split, India made its earnest efforts to seize on nuclear technology to produce electricity. Aspirations to be a nuclear power generation country arose with the nation’s independence, but it took two decades to realize it. In 1964, India entered into an agreement with General Electric (GE), USA to build Asia’s first ever nuclear power reactors. With little experience in making and running nuclear reactors, India opted for a turnkey contract with GE. Two Boiling Water Reactors, 210 MWe capacity each, started to grow on the west coast at Tarapur in Maharastra, near India’s commercial capital Mumbai. On April 01, 1969 when other countries celebrated the Fool’s Day by hoaxes and pranks, India made its maiden foray into nuclear power generation : The first unit of nuclear electricity produced by splitting of uranium atoms was fed to the national grid. And India became the first country in Asia to accomplish such a scientific feat. Months after Tarapur Atomic Power Station (TAPS) started supplying electricity to the national grid, both the units of the project, TAPS-1 and TAPS-2 commenced commercial operation on October 28, 1969.
Foundation for a long-term energy plan
While gaining experience in nuclear power plant operation at Tarapur, India wanted to push forward with its nuclear ambitions. Parallelly, it made attempts to put in place some more nuclear power plants in the country. But this time, it chose different place and different technology. Rawatbhata near Kota in Rajasthan was the place identified for the new reactors. And Pressurised Heavy Water Reactor (PHWR) that uses heavy water (D2O) as coolant and moderator was narrowed down as an ideal technology. The choice of PHWR was based on a sound plan drawn up by Dr. Homi J. Bhabha who was instrumental in bringing nuclear technology to India.
A fast growing nation, India would need an enormous amount of energy to meet out its dreams to be a developed nation. But with limited domestic reserves of fossil fuel, Bhabha understood, India wouldn’t be able to fulfill the ever growing energy demands of the country and would soon run out of resources if an alternate is not thought of. But he knew that India is bestowed with vast thorium reserves, that about of 30% of world thorium exist in the country along Kerala and Tamilnadu coasts. So, he contrived a three phased plan to harness this great but untapped potential. Upon implementation, he believed, this nuclear porogramme will certainly be a solution to the energy woes of the country.
Here is the plan: In stage one, PHWR technology that uses natural uranium as fuel are to be deployed to produce electricity. In the atomic process, the isotope U-238 present in the natural uranium gets converted into Pu-239. In stage two, Fast Breeder Reactor (FBR) shall be brought in use to generate electricity. Along with Pu-239 (that can be extracted from the spent fuel of PHWR), the abundantly available thorium shall be used as blanket. Once the fuel produces heat energy which is finally converted as electricity, it becomes U-233. In stage three, the Advanced Heavy Water Reactor (AHWR) that can use U-233 with Thorium as fuel can be employed for power production. In this technology, the spent fuel will be same as the fuel. That is, the reactor uses U-233 as fuel and after producing energy it gives back U-233 as spent fuel. That means, once the third stage of this power programme is attained, same fuel can be reused multiple times to generate electricity. Upon successfully accomplishing all the three stages, India no longer has to look for support from other countries in meeting its energy demands. With the domestic resources (mainly thorium), it can be addressed. And thus the three-stage nuclear power programme will pave a path for energy independence.
So, the first step in this insightful plan is to have PHWRs. Although India made headway in nuclear field with the Tarapur reactors, it still was a novice. Particularly, in commercial PHWR it had no expertise then. So, India sought technical support from Canada. Based on the CANDU reactors, India had established its first set of PHWRs in Rajasthan Atomic Power Station (RAPS). Two units, RAPS-1 and RAPS-2, came into service in 1973 and 1981 respectively.
Native nuclear power reactors
If 1970s demonstrated the technological expertise, the next decade 1980s emerged as an indigenization period. India took firm steps to build nuclear power reactors on its own and set off for expansion. With the technical know-how gained from the earlier reactors in RAPS and TAPS, Indian engineers and nuclear scientists began to construct the MAPS reactors in early 1970s. A meticulous plan was made, improved design was created, high precision manufacturing of nuclear components was carried out and state-of-the-art construction techniques were used. Eventually, unit-1 became operational in 1984 and unit-2 in 1986. The twin units in Madras Atomic Power Station (MAPS), both 220 MWe PHWR, are the first home-grown nuclear power reactors in the country.
With MAPS, India developed mastery over the 220-MWe PHWR reactors and raised the bar at par with international standard. With the standardized design for 220-MWe PHWR, India went ahead in constructing more nuclear power reactors in the country. In the same decade, works for two new reactors were kick-started at Narora in Uttar Pradesh. The second set of indeginously developed reactors, of Narora Atomic Power Station, began to supply the commercial power since 1991 and 1992 respectively.
If 1980s saw indigenization and standardization of nuclear power technology, the following decades came as an era of consolidation of technology and expansion. With TAPS, RAPS, MAPS and NAPS the Indian nuclear team became technically sound in the PHWR technology. To add two more reactors in the series of 220 MWe PHWRs, another new site was identified at Kakrapar, near Surat, in Gujarat. On the banks of Moticher lake India’s fifth pair of nuclear power reactors, units 1 and 2 of the Kakrapar Atomic Power Station (KAPS), were established in early 1990s. Shortly after NAPS reactors became commercial, the unit-1 of KAPS started to supply commercial power in May 1993 and its twin KAPS-2 in September 1995.
With Kaiga Generating Station (KGS), located amidst western Ghats in Karwar District in Kanataka, the commercialization phase of Indian nuclear power programme dawned. The sixth pair of PHWRs were established on the banks of Kali river in Kaiga in 2000. In the meanwhile, the Indian nuclear team invested its best efforts for the expansion of the nuclear power programme. Around the same time Kaiga reactors were built, two more similar reactors were being constructed at Rawatbhata which became operational in 2000. After RAPS – 3&4 came to existence; further expansion in the site took place to have two more reactors. Similarly, two more reactors were also added at KGS.
Augmentation of capacity: From 220 to 540 to 700
Having shown its prowess in establishing small nuclear power reactors (100 MWe to 220 MWe), the Indian nuclear power community started to look beyond it. From 220 MWe it made initiatives to at least double the capacity of the reactors to maximize the efforts of nuclear power generation. At Tarapur where India’s first nuclear power reactors were established, two higher capacity reactors, 540 MWe size, were established in 2005 and 2006. Scaling up yielded good results. What’s more? With the augmented Tarapur reactors working fine and has been supplying a large amount of electricity, now India is making even more larger PHWRs at two of its sites namely Kakrapar and Rawatbhata. These 700 MWe reactors have been designed in-house and are being built domestically.
On one hand India has been strengthening its PHWR capabilities year after year, while on the other it ushered in the commissioning of second stage reactor to utilize the spent fuels of PHWRs. A 500 MWe Fast Breeder Reactor is coming up quietly at Kalpakkam near Chennai.
The four-digit power
If the west coast of the country holds a distinction of supplying maiden nuclear electricity, the southern coast holds a distinction of flowing four-digit power from one unit. Producing 1000 MWe or more from a single unit was only a dream before the coming of Kudankulam Nuclear Power Project (KKNPP) in southern Tamilnadu.
The third largest electricity producer in the world after China and United States of America, India has an installed capacity of over three lakh megawatts electric. There are more than 650 thermal power units, about 350 hydropower units, about 50 solar power stations, over a few thousand windmills and 22 nuclear power reactors. But, among all, the unit-1 of KKNPP only
could place India in a list of countries which have four-digit power units. On June 07, 2014 India’s largest electricity plant of any kind KKNPP-1 touched its maximum production capacity of 1000 MWe for the first time and grabbed the attention of the world. Nearly after two years, India’s second largest power unit, the Kudankulam Atomic Power Project -2 began the supply of another 1000 MWe power to the southern grid.
To date, India operates 22 nuclear power reactors with an installed capacity of 6780 MW. And nine more reactors with an installed capacity of 6700 MW are under construction.
The first unit of Kagia Generating Station in Karnataka, a indigenous 220 MWe Pressurised Heavy Water Reactor, has set a new record of continuous operation of over 850 days. It surpassed the record of another Indian PHWR, the Rajasthan Atomic Power Station – 5, which ran for 765 days, and became the world’s second longest run nuclear power reactor.
It has been almost 50 years since India first split the uranium atom to generate electricity. In this half a century nuclear power generation, India has maintained a flawless safety record and has marked over 485 reactor years of safe operation. Since the commencement of commercial operation, all the 22 nuclear power reactors in the country have generated 600073 million units of electricity (as on July 2018). And Asia’s first nuclear power reactors, TAPS-1 and TAPS-2 are supplying electricity even today in a reliable manner. The average cost of nuclear electricity per unit is rupees three, while the TAPS-1&2’s power cost is about one rupee.
The nuclear voyage India undertook in the past five decades illustrates how India has grown as a magnificent nuclear power nation from its nascent stage. It also portrays how the country reinforced its capabilities in the field of nuclear power generation, and diversified the technological expertise from Presurrised Heavy Water Reactor to Fast Breeder Reactor.