ACER

ACER (the Agency for the Cooperation of Energy Regulators) was established in 2009 under the EU's Third Energy Package and became fully operational in 2011. Headquartered in Ljubljana, Slovenia, it coordinates national energy regulators across the EU's 27 member states plus Norway, Iceland, and Liechtenstein. Under the 2019 REMIT II update and the 2024 REMIT amendments, ACER acquired direct investigatory and sanctioning powers over energy market manipulation and insider trading across gas and electricity wholesale markets, a significant expansion beyond its original coordination mandate. Prior to 2024 it could only refer matters to national regulators; it can now open cross-border investigations independently.

ACER's institutional role spans market surveillance, technical standard-setting, and infrastructure coordination. It publishes the REMIT Quarterly (market manipulation surveillance data), the Annual LNG Report, gas wholesale congestion reports, and network code opinions. On infrastructure, it issues opinions on derogation requests that allow member states to exempt specific cross-border interconnectors from standard capacity-allocation rules. ACER's data and reporting functions make it the principal reference source for EU-level energy market statistics, including storage utilisation, LNG import shares, congestion revenues, and REMIT Suspicious Transaction and Order Reports (STORs). In 2025 it logged 204 STORs, double the 2024 figure, signalling a marked increase in surveillance intensity under the new enforcement regime.

ACER occupies the bridge between national regulators and the European Commission: it advises on legislation, produces the analytical baseline that informs Commission regulatory decisions, and coordinates cross-border enforcement where a manipulation or transparency breach spans multiple jurisdictions. Its 11 June 2026 workshop activates expanded cross-border investigatory powers acquired under the 2024 REMIT revision, making the second half of 2026 the first full enforcement cycle under the new regime.

ACER has been the dominant regulatory voice in the 2026 European energy markets series, producing consequential output across REMIT enforcement, LNG market structure, infrastructure derogations, and gas wholesale congestion.

On REMIT 2.0, two new implementing instruments entered force 29 April 2026 with no general transition relief and no simultaneity waiver: contracts on 28 April fell under the old one-month reporting window; identical contracts on 29 April fell under the new 14-day window. ACER's compliance consultation ran to 12 June 2026, meaning participants had to comply from 29 April against guidance still formally open to revision. The REMIT 2.0 T+10 Deadline landed on 12 May 2026 with no first-week enforcement action, but ACER's enforcement report confirmed 204 STORs in 2025 and called for improved surveillance by trading intermediaries.

ACER's Annual LNG Report 2025, published 13 May 2026, confirmed that US suppliers provide 58% of EU LNG imports, projected to reach 65% in 2026 as Russian short-term contracts expire under the 25 April ban. EU LNG imports reached a record 146 bcm in 2025, with 980 spot cargoes and a calculated 27 bcm shortfall attributable to Hormuz disruption. Commission EVP Teresa Ribera cited the 58% figure to warn against replacing one energy dependency with another.

On gas wholesale congestion, ACER published its congestion report on 29 May 2026, framing a 'new equilibrium': contractually congested network sides fell to approximately 24 in 2025, down from roughly 50 at the 2022 crisis peak, with congestion revenue stabilised near EUR 140m. The institutional 'new equilibrium' framing sits in tension with ACER's own winter gas wholesale report, which found Central European hub premiums above EUR 2/MWh over TTF, showing that delivered gas east of the benchmark still costs more than the headline price implies.

On infrastructure derogations, ACER issued Opinion 06/2026 in May 2026 recommending a Kiskundorozsma-1 interconnector capacity-allocation derogation for Hungary and Serbia, with the European Commission decision window closing 5 August 2026. ACER separately named Hungary and Slovakia in its TurkStream derogation opinions, both pending the August ruling. ACER's Electricity Network Tariff Repository (published 20 May 2026) provided the first EU cross-border power tariff transparency tool, estimating EUR 580m in avoidable consumer costs from incomplete cross-zonal capacity enforcement in Southeast Europe in summer 2024.

ACER published its first mandated Russian-gas phase-out monitoring report on 1 July 2026, finding Russian gas still supplied roughly 12% of EU demand despite the 18 March short-term import ban: Russian LNG imports actually rose 17% year-on-year (18 March-31 May) and pipeline imports rose 5%, while flows through Turkiye's Strandzha-1 entry point fell 65%. The report separately mapped 45-55 bcm/year of contracts still running under exemptions, pipeline deliveries continuing into Hungary, Slovakia and Greece and LNG cargoes landing in Spain, France, Belgium and the Netherlands, until the full ban takes effect in November 2027.