1) Background
The IAEA identified through the comprehensive safety assessment of VVER-1000 reactors that the existing DC supply, in particular batteries to be a safety issue because of the following:

• Capacity of the batteries should be checked to ensure that the safety functions are fulfilled when needed. Their capacity should follow the guidelines given in the IAEA document 50-SG-D7 [106].
• Emergency operating procedures should address reduction of DC users in case of total station blackout to extend battery discharge time as much as possible.
• The proposed measures are endorsed.
• The battery monitoring strategy should be improved by installing automatic battery circuit monitoring equipment.
• The batteries should be seismically protected.

In order to address above issue, the EC decided to launch a Tacis project that would provide for equipment solution of this safety issue.
2) Objectives
This project aimed at the replacement of original batteries in the plant power supply system. The original batteries did not meet the western requirements for this type of equipment: they did not have the required capacity, were not seismically resistant and caused maintenance problems due to sulphuric acid evaporation in the battery room.
At the same time, this project aims at transferring to Khmelnitsky NPP (KhNPP) I&C personnel Western know how to prepare corresponding equipment technical requirements, commissioning operational and maintenance procedures.
The EC Consultant implemented this project through the OSA activities at KhNPP. The transfer process was based on theoretical training and complete analysis under the EC Consultant’s responsibility.
3) Project results–achievements
This project involved the following activities:

• Elaborating Equipment Technical Specifications for batteries replacement;
• Fabrication and follow up;
• Test results;
• Maintenance and testing procedures;
• Testing and commissioning procedures;
• Licensing documentation;
• Deliver and installation of the equipment.

4) Comments
This project was fully completed in October 2001 with the issuance and signature of the Certificate of the Final acceptance.
Further Information
Further information on the project results could be sought from the beneficiary organizations.
The Project Final report is available at the JRC-IE archive.