reactor Two reactors are now in operation: a
BN-600 fast breeder reactor, generating 600
MWe gross and a
BN-800 fast breeder reactor, generating 885
MWe gross. The BN-800 is the largest
fast neutron power reactor in service in the world. Three turbines are connected to the BN-600 reactor. The BN-600 reactor core is tall and has a diameter of . It has 369
fuel assemblies, each consisting of 127 fuel rods with an enrichment of 17–26%
235U. In comparison, typical enrichment in other Russian reactors is in the range of 3–4% 235U. BN-600 reactors use liquid
sodium as a coolant. The station lacks a
containment building. Construction started on the larger BN-800 fast breeder reactor in 1987. Protests halted progress in 1988, but work resumed in 1992 following an order by President
Boris Yeltsin. Financial difficulties resulted in slow progress. Construction costs have been estimated at 1 trillion
rubles and the new reactor was expected to be finished in 2012–2015. The BN-600, which began operating in 1980, was originally planned to be decommissioned in 2010, but has been life-extended to 2040. On 27 June 2014, controlled nuclear fission started in the BN-800 fast breeder reactor. The newest reactor helps to close the nuclear fuel cycle and to achieve a fuel cycle without or with less nuclear waste. Russia was, at the date, the only country that operates fast neutron reactors for energy production. However issues detected during low power operation required further fuel development work. On 31 July 2015, the unit again achieved minimum controlled power again, at 0.13% of rated power. Commercial operations are expected to start before the end of 2016, now with a power rating of 789 MWe. In December 2015, Unit 4 was connected to the national grid. == See also ==