  The Ireland and Northern Ireland power system is in a period of rapid
transition from conventional generation to renewable generation and has seen a
rapid increase in large demand sites requiring connection into the backbone
transmission system. The role of EirGrid and SONI as Transmission System
Operator in Ireland and Northern Ireland is to operate, maintain and develop
the electricity transmission network. EirGrid ensures that new transmission
projects are developed in a way that balances technical, economic, community
and other stakeholder considerations. This has resulted in much more detailed
evaluation of planning options to maximize utilisation of the existing network
which may include but are not limited to uprating the capacity of the existing
transmission system mainly through the thermal or voltage uprate of existing
circuits. Another method to increase network utilisation is to strategically
deploy Power Flow Control devices to relieve system overloads and maximise
network transfer capacities. EirGrid has developed a new grid development
strategy that places particular emphasis on identifying technologies to help
resolve network issues. This paper presents the study findings for the
application of a power flow controller (PFC) to relieve system issues.
