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Bulgaria’s NEK tenders replacement of two units at Chaira pumped-storage plant

Natsionalna Elektricheska Kompania (NEK), Bulgaria’s state-owned hydropower producer, invites bids by 15 November for the supply and replacement of generators, turbines, main and auxiliary equipment, and control systems for units 1 and 4 of the Chaira pumped-storage hydropower plant.

The contract, which is expected to be completed within 42 months, and which has an estimated value of Lev 220.527 million (US$ 125.6 million/ EUR 112.7 million), includes the design, manufacturing and delivery of equipment, dismantling of the existing components and installation of the new equipment, designer’s supervision, testing and commissioning, training of personnel and rectification of defects within the warranty period of the entire equipment.

The contractor will be required to ensure the adaptation of the new units to the plant’s other systems, as well as to provide participation in the primary and secondary frequency regulation of the grid and the supply of emergency restoration line corridors of the power system, in accordance with the contract, according to the procurement notice published on 17 September.

Chaira, located in southwestern Bulgaria, is the largest pumped-storage plant in southeast Europe, with an installed capacity in generating mode of 864 MW and 784 MW in pumping mode. It plays a crucial role in securing and balancing Bulgaria’s electricity grid. It comprises four single-stage units, each with capacity of 216 MW in generating mode and 197 MW in pumping mode, in an underground power plant. The Chaira reservoir acts as the lower basin and the Belmeken reservoir as the upper basin. The average daily operation of the plant, which is limited by the volume of the lower basin, allows for continuous operation with full power in generating mode for 8.5 hours and in pumping mode for 11 hours.

The contractor shall be required to comply with the provisions of the legal acts in force in the Republic of Bulgaria, including the Environmental Protection Act, the Waste Management Act, the Spatial Development Act, the acts on their implementation and the applicable strategies, plans and programmes for environmental protection, as well as the requirements of NEK, the contracting authority, regarding environmental protection and the resulting obligations thereof.

The minimum warranty period for the delivered and installed technological equipment, machines and facilities is 36 months, counting from the date of a bilaterally signed protocol without notes for successfully conducted 72-hour tests. The estimated service life of the completed civil and erection works and installed equipment should be not less than 50 years.

The scope of contract also includes the training of the contracting authority’s personnel for operation and maintenance of the newly installed equipment and systems, which shall be carried out prior to completion of each unit.

Interested bidders should be registered in the Central Professional Register of Builders (CPRB) at the Chamber of Builders in the Republic of Bulgaria and hold a valid certificate for the execution of construction works of the Third Group, first category, according to Article 5, paragraph 6 of the Regulations on the procedure for registration and maintenance of the Central Professional Register of Builders (CPRB), and for foreign persons – in a similar register according to the legislation of the state in which they are established.

Each participant for the last three completed financial years must have a minimum total turnover of BGN 150 million and a turnover in the area covered by the procurement of BGN 50 million. Bidders should have performed during the last 15 years, as of the date of submission of the offer, at least one identical or similar contract to the subject of the public procurement.

Bid documents shall be submitted for participation in this procedure through the Centralized Automated Information System for Electronic Public Procurement (CAIS EOP). Communication between the contracting authority, bidders and the contractor(s) of the public procurement shall be carried out via the platform. The full tender notice including technical specifications, bidding instructions and documents can be viewed in English and Bulgarian at: https://app.eop.bg/today/404888.

For further information, contact: Rosita Dimitrova at Email: rositsa.dimitrova@nek.bg; Tel.: +359 29263420.