By M.V. Ramana

India's Prototype Fast Breeder Reactor (PFBR) has been delayed again, perhaps until mid-2017. According to an official statement presented in the Parliament of India on 28 July 2016, the Prototype Fast Breeder Reactor (PFBR) is now expected to reach "first criticality by March 2017".

However, even this date is uncertain and an unnamed source within India's Department of Atomic Energy told The Hindu, a leading newspaper in India, that "reaching first criticality might take 'a couple of more months from March 2017'".

The PFBR, whose construction started in 2004 and which was originally expected to become critical in 2010, has been delayed repeatedly. In early 2015, according to P. Chellapandi, the chairman and managing director of Bharatiya Nabhikiya Vidyut Nigam Ltd (BHAVINI), which is building the reactor, the PFBR was expected to attain criticality by either June or July 2015 and begin producing power by September 2015, with commercial operation by the last quarter of 2016.

According to the World Nuclear Industry Status Report, the PFBR is currently among the reactors in the world that have the dubious distinction of being "under construction" for the longest periods of time.

An important reason for the delay in the completion of the PFBR has likely been problems in the production of Mixed Oxide Fuel elements for the core of the PFBR. According to the director of the Bhabha Atomic Research Centre, as of October 2015, only: "90% fuel pins for the core has been fabricated". The PFBR core "consists of 181 fuel subassemblies" (85 with 21% PuO2 content and 96 with 28% PuO2 content) and each fuel subassembly is made up of 217 pins; each pin has a "1000 mm column of MOX" and an upper and a lower column of depleted uranium.