ACER finds Irish gas transmission tariffs largely compliant with EU rules, but calls for clarity on the Corrib Linkline service
ACER finds Irish gas transmission tariffs largely compliant with EU rules, but calls for clarity on the Corrib Linkline service
What is it about?
Today, ACER releases its report on the Irish gas transmission tariffs directed at the Commission for Regulation of Utilities (CRU), Ireland’s national regulatory authority (NRA).
The report assesses whether the proposed reference price methodology (RPM) complies with the requirements of the EU Network Code on Harmonised Transmission Tariff Structures (NC TAR).
What is the proposed tariff methodology?
The Irish NRA proposes to:
Apply a forward-looking matrix methodology based on marginal expansion costs, allocated between entry and exit points. Under this approach, differences between tariffs at network points would reflect the expected unit cost of expanding the pipeline, rather than historical costs.
Apply the same tariff to all exit points serving domestic consumption and a single tariff to all future renewable gas production points, regardless of their location.
Set rules on tariff discounts for any future storage and LNG facilities.
Continue recovering allowed revenues for transmission services through a combination of capacity- and commodity-based tariffs. Capacity tariffs are charged for contracted network capacity, while commodity tariffs are based on transported gas volumes and recover the related costs.
Treat the Corrib Linkline (the pipeline connecting the Corrib offshore gas field to the main ring of the Irish gas network) separately from the transmission service, recovering its costs through a separate tariff.
What are ACER’s key findings?
After analysing the consultation document, ACER concludes that:
The proposed methodology meets the EU requirements on cost-reflectivity, transparency, avoidance of cross-subsidisation, non-discrimination, volume risk and prevention of cross-border trade distortions.
The criteria for setting the flow-based charge are also met.
The criteria for setting non-transmission tariffs are not fully met, as the Corrib Linkline is treated similarly to a non-transmission service but not formally classified as such.
The capacity forecasts used in the methodology are based on Ireland's Network Development Plan for 2024, which may not fully capture more recent demand shifts.
What does ACER recommend?
ACER recommends that the Irish regulator, when adopting its final decision:
Improve the description of the revenue and tariff structure of the Corrib Linkline and formally classify its use as a non-transmission service.
Update capacity forecasts using more recent estimates and, if these show cross-system flows, reassess the methodology against the relevant NC TAR principles.
ACER also recommends that, as part of its upcoming review of the tariff methodology, the Irish regulator assess whether a methodology based on forward-looking marginal expansion costs remains appropriate in the context of the energy transition and declining gas demand.
Next steps
The Irish NRA has until 16 December 2026 to adopt a motivated decision on the reference price methodology.
See all ACER reports on national tariff consultation documents.