Bilibino NPP is a unique facility in the center
of Chukotka
4,5 km
from the administrative boundary
(Bilibino town)
Bilibino NPP is situated in the extreme North-East of Russia above the Arctic Circle, in the permafrost region, in the Chukotka Autonomous District. The plant operates in a self-contained power system in load control mode.
The nuclear power plant generates 80% of electric power produced in the self-contained Chaun-Bilibino power system and is the main heat supply source of its satellite town, Bilibino.
145mln kWh
of electric power were generated by the NPP in 2020
36MW
plant installed capacity
EGP-6 type reactors with the capacity of 12 MW are the “heart” of Bilibino NPP
12,8
years of operation of power unit No. 3 with no failures – a record among Russian NPPs
Bilibino NPP consists of 4 power units with EGP-6 reactor units (pressure-tube uranium-graphite units).
The NPP reactor unit is comprised of the following: a reactor; a natural coolant circulation circuit with a protection and control system; a (reactor) control and protection system circuit; a gas circuit; a maintenance cooldown system; an emergency cooling water supply system (ECWSS).
The process flow chart of Bilibino NPP units belongs to the single-loop type. The controllable chain reaction occurs in the reactor core: fuel (uranium dioxide U235) shares its thermal neutrons.
Heat is removed by water circulating through fuel channels along the natural circulation circuit. The steam-water mixture flows from the reactor to the drum separator, where it is separated into steam and water. Dry saturated steam is supplied to the blades of the turbine, thus driving the turbine and the generator.
Exhaust steam from the turbine enters the condensers to be cooled down there. After purification, heating and deaeration (degassing), condensate returns to the drum separator, where it is mixed with feed water and supplied to the main circulation circuit (MCC).
Electric power produced by the turbine generator is transmitted to an indoor switchgear (ZRU-110 kV) and then is distributed to the Chaun-Bilibino Energy Hub by a VL-110 kV high-voltage power line. Heat supply system water heated by steam from the turbine in boilers is delivered to the Bilibino heat supply station servicing the town.
Order of Rosenergoatom JSC No. 9/621-P dated June 18, 2015 on the Implementation of Measuresn has put into force Measures for the Preparation of Bilibino NPP Power Units for a Final Shutdown No. BILAES MR-100K (04-03)-2015 dated June 8, 2015.
To date, power unit No. 1 of Bilibino NPP is has been shut down and spent nuclear fuel has been removed from the reactor core to a spent fuel pool. The power units No. 2, No. 3 and No. 4 are in operation. They ensure a reliable supply of electricity to consumers in the Chaun-Bilibino Energy Hub and supply heat and hot water to consumers in the town of Bilibino.
The heat output of the reactor unit was selected taking into account the requirement that the electric power of one power unit must not exceed 12 MW due to a low total capacity of the Chaun-Bilibino power system. A sudden outage of such unit will not result in a total outage of the power system.
≤ 12MW
electric power of one
power unit
95,5T/h
necessary steam production capacity of the reactor unit
The EGP-6 reactor (power heterogenous loop reactor with 6 coolant circulation loops) is a graphite-moderated water-cooled heterogeneous loop pressure-tube thermal-neutron power reactor with natural circulation that has a direct-cycle configuration.
The reactor is used for generating electricity and heat.
The power units of Bilibino NPP have a high safety performance. Their main safety features include the principle of self-protection of the reactor unit and the use of safety barriers (the defense-in-depth concept).
All power units are equipped with a containment system preventing any release of radioactive substances into the environment.
The defense-in-depth concept is applied to compensate for potential human errors or mechanical failures. This concept is based on several levels of protection with a sequence of barriers on the way of discharge of radioactive materials into the environment. This concept involves protection of the barriers through prevention of a damage to the plant or to the barriers. It includes further measures to protect the population and the environment against any impacts if the barriers are not sufficiently effective.
The first barrier is a fuel matrix (i.e. a pellet).
The second barrier is fuel cladding. In order to avoid leaks and to identify any faulty fuel elements, a fuel failure detection system is provided.
The operating principle of this system is based on measurement of the steam-water mixture radioactivity at an outlet from each channel. If a leaking fuel assembly is detected (a fuel assembly consists of multiple fuel elements), it is removed from the reactor last, and a new one is installed in its place.
The third barrier is comprised of fuel channels, pipelines, and the circuit equipment. The state of the channels is assessed by monitoring the composition of nitrogen-helium mixture circulating through the reactor space.
The forth barrier consists of reinforced concrete walls of the building housing the circuit equipment (protective boxes). The temperature of concrete beyond the thermal protection structure is constantly monitored and recorded.
EGP-6 reactors have a configuration of the reactor core ensuring “self-protection” or “self-regulation” of the reactor. When the reactor power increases and, consequently, the temperature of the reactor core rises, the nuclear reaction dies out due to natural feedback.
In order to stop the chain reaction quickly and efficiently, neutrons involved in this process must be absorbed. An absorber (boron carbide) is used to accomplish this. Rods made of boron carbide are inserted into the reactor core to reduce the neutron flux level or to shut down the reactor completely.
Electromagnets are used as the drives for the rods to ensure their immersion into the reactor core. This principle guarantees that the rods will drop even if the power unit is de-energized: the powered down electromagnets will stop holding the absorber rods and these will drop down by gravity.
Another way to stop the chain fission reaction is to increase the concentration of boric acid in the coolant: where necessary, the boric acid solution is used by numerous emergency systems.
Bilibino Nuclear Power Plant has been operating safely and reliably over the entire period of operation in all areas of its operation, including ensuring environmental safety
The findings of environmental radiation monitoring carried out by specialists confirm that over many years of its operation, Bilibino NPP has made no impact on the regional environment. Specifically, regular analyses of source and waste water prove that the nuclear power plant has no adverse effect on water bodies.
Monitoring systems inside Bilibino NPP and the automated radiation monitoring system (ARMS) constantly monitor the radiation level in the buffer area and in the control area in real time.
The ARMS continuously monitors the radiation level and transmits the necessary information to Bilibino NPP and environmental radiation monitoring systems.
In this way, the enterprise strives to provide a safety level at which the impact on the environment, the personnel and the population does not exceed the prescribed limits, while the risk of occurrence of emergency situations is minimized.
Bilibino Nuclear Power Plant
Branch of Rosenergoatom JSC
Bilibino NPP, Bilibino town,
Chukotka Autonomous District
689450
Tel.: +7 (42738) 2-56-33
Fax: +7 (42738) 2-50-83
E-mail:
bilnpp@chukotka.ru