Today, ACER releases its report on the Slovak gas transmission tariffs directed at Eustream, Slovakia’s transmission system operator (TSO).
The report assesses the compliance of the proposed reference price methodology (RPM) with the requirements of the EU Network Code on Harmonised Transmission Tariff Structures (NC TAR).
What is the proposed tariff methodology?
The Slovak TSO proposes to:
- Change the current methodology to introduce new tariffs in the middle of the ongoing tariff period, which would result in a tariff increase of more than 70%. The TSO cites exceptional circumstances (a large drop in cross-system flows) as the reason for this change.
- Apply a uniform postage stamp reference price methodology with an ex-ante entry-exit split for 2026-2027.
- Continue recovering transmission revenues through a mix of capacity-based and commodity-based charges.
- Adjust capacity tariffs at all entry and exit points (including domestic points) through benchmarking, using a wide set of European TSO tariffs as a reference.
- Keep two commodity-based charges in place: a flow-based charge paid in kind and a complementary revenue recovery charge.
What are ACER’s key findings?
After analysing the consultation document, ACER concludes that:
- The proposed methodology meets the EU requirement on non-discrimination.
- Compliance with other NC TAR requirements (including transparency, cost-reflectivity, avoidance of cross-subsidisation, volume risk and the prevention of cross-border trade distortions) cannot be confirmed.
- The proposed commodity-based charges are also non-compliant.
