Tender Announcement  for Equipment Maintenance Services for Units 5 and 6 of the KOZLOCLUY Nuclear Power Plant, Bulgaria

I. Basic Points

Tender Type: Service

Project Name: Execution of maintenance and replacement activities for main and auxiliary equipment and systems of Nuclear Units 5 and 6 during the planned annual maintenance in 2026 and/or related thereto

Procurement Method: Negotiated procedure with invitation to compete / Competitive Negotiation

CPV Code: 50000000

II. Technical Requirements

Technical Specifications: Activities must comply with the nuclear power plant design and the requirements of the equipment designers and manufacturers.

Technical Standards: Must possess a Certificate of Approval for Welding Production, compliant with (БДС) (EN) ISO 3834-2 or equivalent standard; Must possess a Certificate of Conformity for Production Control of Steel Structures, compliant with (БДС) EN 1090-1 EXC Class 4 or equivalent standard.

Quality Standards: Must implement a certified management system, compliant with БДС EN ISO 9001:2015 or equivalent standard, with scope covering maintenance of power plant equipment and installations.

Technical Documentation Submission Requirements: Must submit a list containing the organization's name, certification certificate number, issuing body, validity period, and certification scope.

Testing and Acceptance Criteria: The bidder must have an organization certified according to БДС EN ISO/IEC 17020 or equivalent standard for performing non-destructive testing, destructive quantitative composition testing, metallographic testing; must have an organization certified according to БДС EN ISO/IEC 17020 or equivalent standard (C/A type inspection body) for performing commissioning works, electrophysical quantity control, control of motors, equipment, and installations in electrical equipment.

III. Service Information

Service Type: Maintenance and Repair Services

Service Content: Perform maintenance activities to maintain the operability and reliable operation of main and auxiliary equipment and systems; Perform equipment replacement activities; Support the timely and high-quality execution of the planned annual maintenance of Nuclear Units 5 and 6; Ensure equipment management for its reasonable design life; Perform maintenance activities related to extending the service life of main and auxiliary equipment. Main maintenance activities aim to maintain or increase the reasonable design life of the respective equipment and systems, meet regulatory and supervisory requirements, and ensure the design reliability and availability of equipment and process systems. Auxiliary maintenance activities improve the operating conditions of important safety and production facilities, ensure repairability, restore the service life of equipment and installations, and improve their operational appearance.

Service Period: Start date is April 18, 2026, end date is June 30, 2029. Annual maintenance for Unit 5 is up to 35 calendar days, for Unit 6 up to 35 calendar days. For equipment not involving the annual maintenance cycle and requiring long production lead times, the final completion date is June 30, 2029.

Service Team Requirements: For Subcontract 1, minimum requirement is 32 engineering/technical personnel and 418 execution personnel. For Subcontract 2, minimum requirement is 16 engineering/technical personnel and 224 execution personnel.

Service Objectives: Maintain or increase reasonable design life, meet regulatory and supervisory requirements, ensure design reliability and availability, improve operating conditions.

Service Deliverables: Completion of the scope of works specified in Appendices 1.1 and 2.1

Service Quality Indicators: Performed according to requirements in Technical Specification No. 25.EP-2.T3.1528/01 and the draft contract.

Personnel Qualification Requirements: Engineering/technical personnel and execution personnel with specific professional competencies.

Service Performance Evaluation Method: Evaluation based on tender evaluation criteria.

IV. Implementation Conditions

Project Duration: Start date April 18, 2026, end date June 30, 2029. Planned annual maintenance duration: Unit 5 up to 35 calendar days, Unit 6 up to 35 calendar days. For equipment not involving the annual maintenance cycle, final completion date is June 30, 2029.

Project Implementation Phases: Includes work during annual maintenance periods and outside annual maintenance periods.

Project Start Time: April 18, 2026

Project Completion Time: June 30, 2029

V. Contract Information

Contract Type: Service Contract

Contract Term: Start date April 18, 2026, end date June 30, 2029

Budget Amount: Total estimated value EUR 65,130,760.85 (excluding VAT). Subcontract 1: EUR 47,226,464.98. Subcontract 2: EUR 17,904,295.87

Payment Terms: Payment within 30 calendar days after submission of corresponding documents, upon performance and acceptance of individual scopes of work specified in Contract Appendix 2. Advance payment up to 10% of the contract value for goods and services, payable within ten working days after submission of advance payment guarantee and invoice of equal value. The advance payment will be deducted at 10% from each subsequent payment.

Price Adjustment Mechanism: Not explicitly mentioned.

Subcontracting Allowed: Not explicitly mentioned.

Payment Milestones: After performance and acceptance of each individual scope of work.

Payment Proportions: Advance payment up to 10%, subsequent payments deduct 10% of the advance.

VI. Bidding Requirements

Bid Language: Bulgarian

Bid Submission Method: Electronic submission

Bid Bond: Bid bond not explicitly mentioned, but contract performance bond required at 5% of contract value.

Performance Bond: 5% of the contract value, provided in cash, bank guarantee, or eligible insurance, valid for 30 days longer than the contract term.

Minimum Turnover Requirement: Subcontract 1: Total turnover in the past three years at least EUR 23,613,232, turnover in specific field at least EUR 11,806,616. Subcontract 2: Total turnover in the past three years at least EUR 8,952,147, turnover in specific field at least EUR 4,476,073.

Financial Capacity Requirements: Must submit annual financial statements or turnover certificates.

Company Registration Requirement: Must be registered in the relevant professional register.

Company Qualification Requirements: Must be registered in the Central Professional Register of Builders of the Republic of Bulgaria for Group III, Category I construction; or foreign entity registered in a similar register in its home member state. Must be registered in the register for product technical requirements for maintenance, repair, and modification activities for cranes, electric hoists, pressure vessels, steel pipes for steam and hot water; or foreign entity registered in a similar register in its home member state.

Similar Project Experience Requirement: Within the past 3 years prior to application submission, must have executed activities identical or similar to the subject of the tender (experience in the field of nuclear power plants regarding reactors, turbines, generators (including maintenance of generators with power ≥800 MW), transformers (including overhaul, replacement and transport logistics of main transformers with power ≥630,000 kVA), heat exchange equipment, and primary and secondary circuit pump sets and valves). For Subcontract 2, experience in heat exchange equipment and pump sets, installation and maintenance of support/suspension systems, piping and valves, adjustment and replacement of hydraulic dampers is required.

Project Manager Qualification: Not explicitly mentioned.

Technical Team Size Requirement: See Service Team Requirements.

Equipment Capability Requirement: Not explicitly mentioned.

Consortium Bidding Requirement: Not explicitly mentioned.

VII. Bid Evaluation Rules

Evaluation Method: Comprehensive scoring method

Technical Score: Includes staffing, abnormal response time, warranty service conditions, total 50 points (weight).

Commercial Score: Not explicitly mentioned.

Price Score: Weight 50%

Evaluation Criteria: K1: Presence of personnel and leadership team with specific professional competencies (weight 30%). K2: Response time to abnormalities arising during maintenance and installation activities requiring the use of machining and electrical repair bases for part and node processing or heat treatment (weight 10%). K3: Warranty service conditions, including response time (weight 10%). K4: Bid price (weight 50%)

Scoring Weight Proportions: Technical score (K1, K2, K3) total 50%, Price score (K4) 50%

Comprehensive Scoring Formula: Total score calculated by weighting scores from each criterion. Price score formula: K4 = (P_min / P_i) * 100

VIII. Timeline

Tender Notice Publication Time: Not explicitly mentioned.

Tender Document Acquisition Deadline: Not explicitly mentioned, but bid deadline is also the deadline for submitting requests to participate.

Bid Submission Deadline: April 6, 2026 23:59:59 (UTC+03:00)

Bid Opening Time: April 7, 2026 13:30

Expected Award Time: Not explicitly mentioned.