Unit 1 of India's Kaiga nuclear palnt in Karnataka, an indigenously designed pressurised heavy water reactor (PHWR), was taken offline on 31 December having completed a record 962 unbroken days of operation since 13 May 2016.

On 10 December, the reactor the broke the previous world record for continuous operation (940 days) held by unit 2 of the UK's Heysham 2 plant, an advanced gas-cooled reactor (AGR) since September 2016.

Both PHWRs and AGRs are designed for online refuelling.

Nuclear Power Corporation of India Ltd (NPCIL) said that during its continuous run of 962 days, Kaiga 1 had generated about 5 billion units of electricity at a plant load factor of about 99.3%.

Kaiga 1 began commercial operation in 2000, and is one of four PHWR units at the site.

NPCIL said three of its reactors - Kaiga 1, Rajasthan 3 and Rajasthan 5 - have now achieved continuous operating runs of over two years. Rajasthan 3 operated for 777 days, and Rajasthan 5 for 765 days.

Photo: India's Kaiga 1 (Photo: DAE)