Bilibino 1-4, Russia

Bilibino Nuclear power plant (NPP) in the Chukotka Autonomous Okrug, Russia, houses the world's smallest commercial nuclear reactor. The plant, owned and operated by state-owned Rosenergoatom, is equipped with four EGP-6 light water graphite reactors (LWGR) with gross power capacity of 12MWe each.

The EGP-6 reactors are based on Russia's high power channel-type reactor design known as RBMK (Reaktor Bolshoy Moshchnosti Kanalniy). The four reactors at the Bilibino NPP were commissioned between 1974 and 1976, and have a thermal capacity of 62MWt each.

CEFR (China Experimental Fast Reactor)

China Experimental Fast Reactor (CEFR) currently operating at the China Institute of Atomic Energy in Tuoli, about 35km south of Beijing, is the world's second smallest nuclear reactor. It is a fast breeder reactor (FBR) of BN-20 model with gross power capacity of 25MWe and thermal capacity of 65MWt.

The reactor is owned by China National Nuclear Corporation and operated by China Institute of Atomic Energy. Its construction began in May 2010 and connection to the grid was achieved in July 2011.

The two 35MWe capacity nuclear reactors being constructed for the world's first floating nuclear power station in Russia, called Akademik Lomonosov, rank as the third smallest nuclear reactors. The Akademik Lomonosov floating NPP is expected to begin commercial operation in 2016.

The two KLT-40S 'Floating' pressurised water reactors (PWR) were designed by OKBM Afrikantov and have been under construction since April 2007. Rosenergoatom will own and operate these two reactors each of which have a thermal capacity of 150MWt.

Rajasthan 1, India

The first nuclear reactor unit of the Rajasthan Atomic Power Station located about 65km away from Kota in Rajasthan, India, is currently the world's fourth smallest nuclear reactor. The Rajasthan 1 nuclear reactor, owned and operated by India's Nuclear Power Corporation, has a gross power capacity of 100MWe.

Construction of the horizontal pressure tube type pressurised heavy-water reactor (PHWR) started in August 1965. The reactor started commercial operation in December 1973 and has a thermal capacity of 346MWt.

KANUPP (Karachi Nuclear Power Plant), Pakistan

The 137MWe reactor operating at the Karachi Nuclear Power Plant (KANUPP) in the Sindh Province of Pakistan is the fifth smallest nuclear reactor in the world. It is Pakistan's first commercially operated nuclear reactor and is owned and operated by Pakistan Atomic Energy Commission.

Construction of the reactor unit began in August 1966 and commercial operation commenced in December 1972. It is a CANDU (CANada Deuterium Uranium)-type pressurised heavy-water reactor (PHWR) with a thermal capacity of 433MWt.

Tarapur 1-2, India

The first two of the four reactors operating at the 1,400MW Tarapur Atomic Power Station located 12km from Boisar in Maharashtra, India, are currently the sixth smallest nuclear reactors in the word. The reactors, owned and operated by India's Nuclear Power Corporation, have a gross power capacity of 160MWe each.

Construction of the Tarapur 1 and 2, two boiling water reactor (BWR) units (model- BWR-1 with Mark 2 containment), began in October 1964. Both the reactors started commercial operation in October 1969 and have a thermal capacity of 530MWt each.

Rajasthan 2, India

The second reactor unit operating at the Rajasthan Atomic Power Station, India, is the seventh smallest nuclear reactor in the world. The Rajasthan 2 reactor is a horizontal pressure tube type pressurised heavy-water reactor (PHWR) and has a gross power capacity of 200MWe.

Constructed between 1968 and 1980, and owned and operated by India's Nuclear Power Corporation, the reactor started commercial operation in April 1981 with a thermal capacity of 693MWt.

Shidao Bay 1, China

The reactor unit under construction for the upcoming Shidao Bay NPP near Rongcheng in the Shandong Province of China ranks as the world's eighth smallest nuclear reactor. Shidao Bay 1 is a high temperature gas-cooled reactor (HTGR) with a gross power capacity of 211MWe and a thermal capacity of 500MWt.

The reactor design was developed by China's Tsinghua University, construction began in December 2012 and commissioning is expected in 2017. China Huaneng Group is the owner of the reactor while Huaneng Shandong Shidao Bay Nuclear Power Company will operate the Shidao Bay NPP.

Rajasthan 3-6/ Kaiga 1-4/Kakarapar 1-2/Madras 1-2/ Narora 1-2, India

Units 3-6 of the Rajasthan Atomic Power Station, the four units of the Kaiga Atomic Power Station in Karnataka, the two units operational at the Kakarapar Atomic Power Station (KAPS) in Gujarat, the two units operating in the Madras Atomic Power Station at Kalpakkam in Tamil Nadu, and the two units of the Narora Atomic Power Station in Uttar Pradesh, India, share ninth place among the smallest nuclear reactors in the world. The gross power capacity of these reactors is 220MWe each.

All these reactors are horizontal pressure tube type pressurised heavy-water reactors (PHWR), and are owned and operated by India's Nuclear Power Corporation. Rajasthan 3-6, Kaiga 1-4, Kakarapar 1-2, Madras 1-2 and Narora 1-2 started commercial operation in 2000-2010, 2000-2011, 1993- 1995, 1984-1986 and 1991- 1992 respectively.

Qinshan 1, China

The first reactor unit of the Qinshan nuclear power plant located in the Zhejiang Province of China is the world's tenth smallest nuclear reactor. The reactor unit is owned by Qinshan Nuclear Power Company and operated by CNNC Nuclear Operation Management Company. It has a gross power capacity of 310MWe and thermal capacity of 966MWt.

Qinshan1 is a CNP-300 pressurised water reactor (PWR) developed by China National Nuclear Corporation (CNNC). The nuclear reactor was constructed between 1985 and 1991, and began commercial operations in April 1994.

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