R2.32/94: Independent alternative shut-down system

This TACIS project was part of a programme of work to enhance the safety of the 11 RBMK-1000 reactors in the Russian Federation.
The main objective of this project was to develop a design concept for an independent/alternative shutdown system for these reactors. The project was also to determine means of reducing the void reactivity effect of the Control and Protection System Cooling Circuit (CPS-CC) that might lead to a reduction in the performance requirements of the second shut-down system.
Planned Outputs:
A series of reports was to be delivered documenting the selection of suitable concepts and their development into engineering specifications for approval by the beneficiaries and Russian regulatory authority.
Project Activities:
The requirements for a second shutdown system were to be identified and used to derive assessment criteria. The potential concepts and options were then to be documented and assessed to select the preferred option. This was submitted to the beneficiaries and regulatory authority for initial approval. In the final phase of the project the selected option was to be developed to produce an initial design for approval by the beneficiaries and regulatory authorities.
The studies were to be based on a selected reference unit, and identify the necessary differences in approach for the remaining units.

The project was implemented in three phases.
Phase 1:
Identification of the system requirements, to select the reference unit and to document its existing system;
Assessment criteria and their weightings were also to be developed.
Phase 2:
Assessment of potential options was for identifying concepts, assessing options and carrying out supporting calculations. The preferred option was to be selected and submitted to the Safety Authorities of Russia for endorsement (hold point).
Phase 3:
Development of the design specification including the development of the basic design specification, supported by design calculations and appropriate safety analyses, for the preferred option(s) to enable prototype testing to be included in a future TACIS project.
Additionally, a cost estimate and timescale for completion of demonstration work and implementation of the system on the reference plant and the other RBMK reactors in Russia was provided.
The project can be considered as completed in conformance with the TOR. The project has laid the basis for the implementation of project R1.04/00 - Independent alternative shut-down system.