Electricity Transmission System Operator EirGrid plc TSO

EirGrid plc is Ireland’s state-owned electricity transmission system operator responsible for managing and developing the national high-voltage electricity grid, ensuring a safe, secure, and reliable power supply. It operates independently from ESB, which owns the physical transmission assets. EirGrid also oversees the Single Electricity Market (SEM) across Ireland and Northern Ireland through its subsidiary SONI. The company plays a key role in integrating renewable energy, supporting economic growth, and facilitating competition in the energy market. EirGrid owns and operates the East–West Interconnector linking Ireland to Great Britain and is regulated by the Commission for Regulation of Utilities.