Imperfections Charges October 2025 – September 2026 Consultation Paper
Today, 30th June 2025, the Regulatory Authorities (RAs) are publishing a Consultation Paper on the Transmission System Operators (i.e. EirGrid & SONI) ‘Imperfections Charges Forecast Tariff Year 2025/26’ (i.e., 01/10/2025 to 30/9/2026), prior to issuing its final decision on the Tariff Year 2025/26 Imperfections Charge.
The purpose of this charge is for the TSOs to recover their forecast total costs associated with;
• managing the costs that arise given the transmission system (the wires) cannot deliver the efficient outcomes from the electricity market;, and
• the operational requirements of the electricity system (e.g. minimum number of generating units on requirements, constraints, local Security of Supply (SoS) requirements in Dublin and Northern Ireland).
In their submission, the TSOs forecast an allowance of €883.23 million for the Tariff Year 2025/26, compared to the €567.21 million allowed by the RAs for Tariff Year 2024/25.
The RAs have reviewed the TSOs’ report, and seek stakeholders’ views on any aspect of the proposals and, in particular, on the following:
i. Whether the TSOs’ forecasts of costs and assumptions for Tariff Year 2025/26 are reasonable;
ii. If there are actions the TSOs could take to minimise Imperfections Charges;
iii. Whether the K-factor element (which is projected to be significantly greater for Tariff Year 2025/26 than in previous Tariff Years) should be partially recovered over one or more Tariff Year and, if so, at what quantum.
Responses to this paper should be forwarded to the Market Modelling Group (mmg@cru.ie) and Caroline Winder (caroline.winder@uregni.gov.uk) by close of business on 25th July 2025.
Following consideration of responses received and further review of the TSOs’ submission, the RAs intend publishing a decision in early September 2024.