Reducing the number of must-run, conventional sets in Northern Ireland to enhance RES penetration, while maintaining system stability

The transmission systems of Northern Ireland and Ireland are jointly controlled and operated, by their respective system operators (SOs), SONI and EirGrid, under a collective, all-island, operational policy framework. A solitary, 275 kV double-circuit, known as the North/South tieline (NSTL), serves as the main pathway of jurisdictional interconnection. The foremost contingency of concern, for the safe and stable operation of the All-Island Power System