Customers

Other System Charges (OSC) are levied for non-compliance to provide necessary services to the system. This document sets out the harmonised arrangements for the calculation of Other System Charges by the Transmission System Operators (TSOs), EirGrid in Ireland and SONI in Northern Ireland respectively, in accordance with the Regulatory Authorities' (RAs) Decision Paper SEM-24-057.

SONI and EirGrid held a virtual industry workshop on Thursday 5th September 2024, where the TSOs and our partners Afry presented the All-Island System Services Supplier Charge Consultation Paper and hosted a Q&A session. This document contains the slides presented at the workshop.

​​Approved 2024/25 Generator Use of System Charges (GTUoS) - Accompanying Note

SONI Transmission Use of System Charging Statement 2024/25

Connections Register 15 August 2024 (Excel)

Connections Register 15 August 2024 (PDF)

2024-25-Approved-Transmission-Loss-Adjustment-Factors-(TLAFs)-Accompanying-Note-v1.0.pdf

2024-25-Approved-TLAFs-v1.0.xlsx

2024-25-Approved-TLAFs-v1.0.pdf

Approved 2024/25 Generator Use of System Charges (GTUoS)