By: Donald Jones, retired nuclear industry engineer, 2019 April 1
Most of India’s nuclear reactors are of the pressurized heavy water reactor (PHWR) type with horizontal pressure tubes, just like the Canadian designed CANDU. In fact the first PHWR (not the first nuclear reactor) in India was the Rajasthan Atomic Power Project (RAPP) unit and was a CANDU designed by Atomic Energy of Canada Limited (AECL) that used the Douglas Point unit in Ontario as reference design but modified to aid localization. RAPP-1 entered commercial operation 1973 December. While RAPP-1 was being constructed the design of RAPP-2 was started. However the detonation of a nuclear device by India in 1974 curtailed completion of the design by AECL and India was on its own as far as nuclear technology was concerned. The design was completed by India and RAPP-2 eventually entered commercial operation in 1981 April. Since those early days India has developed its own indigenous designs of PHWRs with net electrical outputs of 202 MW, 490 MW, and 630 MW. They bear little to no resemblance to Douglas Point. All 14 PHWR units operating in 2018 (excludes RAPP-1 which has been shutdown since 2004, Kakrapar units 1 and 2 which were shutdown due to coolant channel leaks, and Madras unit 1 which was shutdown during 2018 for some unknown reason) were 202 MW (220 MW gross) except for two 490 MW (540 MW gross) units. There were four 630 MW (700 MW gross) units under construction with none in operation. All PHWR power units, except for RAPP-1, are designed, owned, and operated by Nuclear Power Corporation of India Ltd. Several of the country’s PHWRs have been refurbished for extended life operation. For more detailed information on the Indian nuclear program see, Nuclear Power in India (reference 1).
The performance data are taken from the Power Reactor Information System (PRIS) database of the International Atomic Energy Agency (IAEA). Note that the Load Factor term used in the PRIS database has the same meaning as Capacity Factor (CF). CFs are based on the (net) Reference Unit Power and on the (net) Electricity Supplied, as defined in the PRIS database, so capacities referenced in this article are net electrical MW output. The lifetime, or cumulative, CF is based on the date of commercial operation and will include the outage time if the unit has been refurbished. Only the performance of India’s PHWRs is reviewed in detail but India’s four operating non-PHWR units are mentioned.
Lifetime CFs and some recent annual CFs have suffered because of uranium shortages and India’s technical isolation because of it not being a signatory to the Nuclear Non-Proliferation Treaty. Things eased somewhat with the Nuclear Suppliers’ Group agreement achieved in 2008 but the civil liability law introduced in 2010 has still restricted access to foreign technology. Some units are not under International Atomic Energy Agency (IAEA) safeguards and cannot use imported uranium and domestic uranium is in short supply. All this has affected and may still be affecting plant performance. Even so at the end of 2013 Rajasthan unit 5 held the world record in lifetime CF at 94.4 percent, according to Nuclear Engineering International magazine (PRIS data give 94.9 percent to end of 2013). On 2014 September 6 Rajasthan unit 5 achieved a 765 day continuous run at full power. On 2018 December 31 Kaiga unit 1 was taken offline for maintenance after completing 962 days of unbroken operation since 2016 May 13, a world record, with a CF of 99.3 percent. This shows what good design and good operation/maintenance can accomplish.
Kaiga-1 entered commercial operation in 2000 November. Annual CF for 2018 was 98.8 percent with a lifetime CF of 73.9 percent.
Kaiga-2 entered commercial operation in 2000 March. Annual CF for 2018 was 100.5 percent with a lifetime CF of 73.7 percent.
Kaiga-3 entered commercial operation in 2007 May. Annual CF for 2018 was 87.2 percent with a lifetime CF of 64.8 percent.
Kaiga-4 entered commercial operation in 2011 January. Annual CF for 2018 was 101.7 percent with a lifetime CF of 84.0 percent
The average annual CF for the four units for 2018 was 97.0 percent and lifetime CF was 74.1 percent. All four units are 202 MW.
Kakrapar-1 entered commercial operation in 1993 May. Was shutdown due to coolant channel leaks.
Kakrapar-2 entered commercial operation in 1995 September. Was shutdown due to coolant channel leaks.
Both units are 202 MW. Unit 1 suffered a small LOCA (loss of coolant accident) on 2016 March 11 when there was a rupture in a fuel channel assembly and unit 2 has been offline since a coolant channel leak in 2015. All coolant channels are being replaced in both units. Replacement work began 2016 July and was completed on unit 2 on 2018 August.
Madras-1 entered commercial operation in 1984 January. Unit appears to be shutdown during 2018.
Madras-2 entered commercial operation in 1986 March. Annual CF for 2018 was 85.5 percent with a lifetime CF of 57.5 percent.
Both units are 205 MW and both were refurbished 2002-2005 for life extension when their capacity was restored back to 205 MW from 155 MW.
Narora-1 entered commercial operation in 1991 January. Annual CF for 2018 was 91.8 percent with a lifetime CF of 58.2 percent.
Narora-2 entered commercial operation in 1992 July. Annual CF for 2018 was 84.1 percent with a lifetime CF of 61.1 percent.
Both units are 202 MW. Unit 2 was refurbished 2009-2010.
Rajasthan-1 entered commercial operation in 1973 December. Annual CF for 2018 was zero percent with a lifetime CF of 17.9 percent.
Rajasthan-2 entered commercial operation in 1981 April. Annual CF for 2018 was 72.5 percent with a lifetime CF of 56.7 percent.
Rajasthan-3 entered commercial operation in 2000 June. Annual CF for 2018 was 75.4 percent with a lifetime CF of 77.1 percent.
Rajasthan-4 entered commercial operation in 2000 December. Annual CF for 2018 was 81.9 percent with a lifetime CF of 79.8 percent.
Rajasthan-5 entered commercial operation in 2010 February. Annual CF for 2018 was 88.2 percent with a lifetime CF of 93.1 percent.
Rajasthan-6 entered commercial operation in 2010 March. Annual CF for 2018 was 87.2 percent with a lifetime CF of 77.5 percent.
The average annual CF for units 2 to 6 (excludes RAPP-1) was 81.0 percent with an average lifetime CF of 76.8 percent. Rajasthan unit 1 (RAPP-1) is 90 MW and unit 2 is 187 MW. Units 3 to 6 are 202 MW. RAPP-1 was shutdown in 2004 and the Department of Atomic Energy, as owner, is considering its future. RAPP-2 was derated in 1990 to 187 MW and has been refurbished. On 2014 September 6 Rajasthan unit 5 completed 765 days of continuous operation at full power. Units at other Indian stations have also had some long periods of continuous operation. At the end of 2013 unit 5 also held the world record for lifetime CF at 94.4 percent, according to Nuclear Engineering International magazine.
Tarapur-3 entered commercial operation in 2006 August. Annual CF for 2018 was 92.1 percent with a lifetime CF of 76.4 percent.
Tarapur-4 entered commercial operation in 2005 September. Annual CF for 2018 was 85.9 percent with a lifetime CF of 67.8 percent.
Tarapur 3 and 4 are 540 MW gross units.
Nuclear units other than PHWRs on India’s grid
Kudankulam-1 began commercial operation 2014 December 31. It is a Russian PWR (pressurized water reactor) with gross electrical power of 1,000 MW.
Annual CF for 2018 was 53.6 percent with a lifetime CF of 50.1 percent.
Kudankulam-2 began commercial operation 2017 March 31 and has same power rating as unit 1.
Annual CF for 2018 was 33.8 percent with a lifetime CF of 39.0 percent.
Tarapur-1 began commercial operation in 1969 October 28. It is a United States General Electric BWR (boiling water reactor) and was India’s first nuclear reactor with a reference electrical unit power (net) of 150 MW (from PRIS) and gross electrical power of 160 MW.
Annual CF for 2018 was 72.1 percent with a lifetime CF of 62.7 percent.
Tarapur-2 also began commercial operation 1969 October 28. Unit 2 has same power rating as unit 1.
Annual CF for 2018 was 41.9 percent with a lifetime CF of 63.6 percent.
Average CF of all PHWRs
The average annual CF of all 14 PHWRs (out of a total of 18) operating in 2018 was 88.0 percent with an average lifetime CF of 71.5 percent.
Kaiga unit 1 holds the world record for continuous operation with an unbroken run of 962 days that ended 2018 December 31.
1. Nuclear Power in India, World Nuclear Association, http://www.world-nuclear.org/information-library/country-profiles/countries-g-n/india.aspx