MaresConnect 750 MW HVDC Interconnector System

Summary

The procurement concerns the construction of the MaresConnect 750 MW, ±320 kV bidirectional high-voltage direct-current interconnector between Ireland and Wales. The link will include approximately 240 km of subsea and onshore cables and new converter stations. The design and delivery works are divided into four turnkey EPC lots: two HVDC converter stations (Lot 1A), an Irish 400 kV AC tail substation (Lot 1B), subsea and onshore HVDC cables and associated Welsh HVAC cables (Lot 2A), and the underground HVAC cable system in Ireland (Lot 2B). Bidders for Lots 1A and 1B must bid for both paired lots, as must bidders for Lots 2A and 2B. Bidders may participate in up to four lots. To participate, a completed Pre-Qualification Questionnaire must be submitted electronically by 31 October 2026 at 12:00 UTC. Price is not the only award criterion. The contractor will be responsible for the design and execution of its lot, under contracts based on the amended 2017 FIDIC Silver Book. The estimated total procurement value is EUR 1 billion.