ACER has published its 2026 Monitoring Report on European liquefied natural gas (LNG) market developments, reviewing key market trends in 2025 and the implications for Europe’s energy security, including the risks linked to tensions in the Middle East.

Worth highlighting, given there is much talk of EU data gaps, that ACER has the overview of EU LNG market. This annual ACER report shows that LNG has become central to the EU gas system as Europe continues to move away from Russian gas. At the same time, it highlights growing exposure to global LNG market risks, including supply concentration, spot market volatility and geopolitical disruptions.

Main highlights

• The EU imported a record 146 bcm of LNG in 2025, confirming LNG’s key role in Europe’s gas supply. The EU is the world's largest importer of LNG.
• Global LNG production increased by 36 bcm, the strongest annual growth since 2022.
• The United States supplied 58% of EU LNG imports in 2025, equivalent to around a quarter of total EU gas demand.
• ACER’s daily LNG price assessments (based exclusively on actual spot transactions) provide much needed transparency on the EU LNG spot price discovery. More than 980 spot LNG cargoes for delivery in the EU in 2025 were reported to ACER in 2025, up from 550 transactions in 2024.
• TTF, the Dutch gas trading hub, remained the main benchmark, used to price 74% of EU spot LNG trades.
• In a full-year Strait of Hormuz closure scenario in 2026, the global LNG market could face a net supply shortfall of 27 bcm compared with 2025, intensifying competition for spot cargoes.

ACER’s recommendations

Recent tensions in the Middle East show how quickly geopolitical crises can disrupt energy flows and drive up prices. In response, ACER underlines the continued strategic importance of REPowerEU and its three pillars for Europe’s energy security:

• Energy savings and efficiency, to reduce gas demand and lower vulnerability to external shocks.
• Diversification of supply sources, to avoid overreliance on individual suppliers or transit routes.
• Faster roll-out of renewable energy, to strengthen resilience by reducing dependence on imported fossil fuels.

For punchy overview of related issues like the impact of Hormuz on EU gas storage filling for winter 2026, see also the recent ACER key developments in European gas markets report (April 2026). 

Today, ACER releases its Opinion on the All-Island Resource Adequacy Assessments for Ireland, Northern Ireland and the Single Electricity Market (SEM) as a whole. The assessment was jointly prepared by the transmission system operators (TSOs) of both jurisdictions (EirGrid and SONI), complementing the European Resource Adequacy Assessment (ERAA) 2025.

What is a resource adequacy assessment?

The ERAA evaluates electricity resource adequacy across the EU and provides a consistent framework to assess whether additional national measures are needed to ensure security of supply. It is carried out annually by the European Network of Transmission System Operators for Electricity (ENTSO-E) and reviewed by ACER.

Member States can complement the European analysis through national adequacy assessments (NRAAs) to reflect local conditions. When a national assessment identifies differences from the European assessment, ACER issues an opinion.

What did ACER find?

ACER finds that most differences between the All-Island Resource Adequacy Assessment and the ERAA are justified, as they reflect national trends and include additional modelling detail, enhancing accuracy. 

ACER also highlights two factors with a major impact on adequacy:

• The planned second North-South Interconnector is included only in the SEM-wide assessment, meaning its contribution to adequacy is not captured in all three analyses. Once operational (expected by 2031), it would help keep adequacy risks in the SEM within the reliability standard in 2033 and 2035, strengthening security of supply across the island and highlighting the importance of increased cross-zonal capacity for resource adequacy.
• The rapid growth of data centres in Ireland (which accounted for 22% of national electricity demand in 2024 and could reach 31% by 2034) poses a key adequacy risk. New policy updates now require data centres to provide onsite or nearby generation equal to peak demand, helping reduce grid reliance and improve flexibility during stress periods. Future adequacy assessments should better reflect both the demand impact of data centres and the extent to which policy measures can mitigate adequacy risks.

What are ACER’s recommendations?

To further strengthen the assessment, ACER recommends that TSOs:

• Include a viability assessment of adequacy resources in the central scenario to confirm the required resources are realistically available. 
• Ensure revenue consistency between market viability and dispatch models so that both tools reflect aligned market revenues and investment signals. 
• Consider multiple revenue streams in the assessment to provide a more robust evaluation of resource profitability. 
• Include the planned second North-South Interconnector in all the three analyses. 
• Consider greater operational flexibility for gas units during periods of scarcity. 
• Incorporate storage and demand response expansion, including flexibility from data centres, for all target years till 2035. 

What are the next steps?

ACER encourages TSOs to consider these recommendations to ensure a more accurate assessment of adequacy risks.

Europe has an EU-wide framework (called 'REMIT') to detect and deter market manipulation and abuse in wholesale energy markets. This framework counts on many parties collecting and monitoring data, all working together to ensure the integrity of Europe’s wholesale energy markets. National energy regulators are responsible for REMIT enforcement.

Today, ACER publishes its annual reports on energy market surveillance, covering:

• The preparedness of persons professionally arranging transactions (PPATs) to detect and report suspicious behaviour. PPATs are trading intermediaries such as energy exchanges, organised market places (OMPs) or brokers, who arrange or facilitate transactions in wholesale energy products.

• National regulatory authorities’ (NRAs’) analysis of suspicious transaction and order reports (STORs) submitted by PPATs, their enforcement actions and penalties.

Both reports are mandated by the 2024 revised REMIT Regulation, which expanded PPATs’ obligations for monitoring trading activity and reporting suspected market abuse to ACER and to the relevant national regulator.

What are ACER’s key findings?

ACER highlights the important role of PPAT market surveillance and NRA enforcement under the REMIT framework. 

ACER’s analysis shows that PPATs’ structural compliance with their REMIT obligations is improving. However, their market surveillance still needs to be strengthened to ensure fair, transparent and well-functioning wholesale energy markets across the EU.

ACER encourages PPATs to review and improve surveillance arrangements, systems and procedures, working in particular on the quality, completeness and timeliness of suspicious transaction and order reports (STORs) submitted via ACER’s Notification platform.

ACER also found that the number and quality of STORs submitted by PPATs in 2025 increased significantly, reaching 204 reports - double the previous year’s figure. In parallel, NRAs made steady progress in screening, prioritising and closing cases.

For PPATs, ACER identified key areas in their surveillance practices where further improvements are needed:

• Strengthen functional independence and professionalisation of surveillance teams, including through appropriate training.
• Reduce reliance on basic monitoring tools in favour of more targeted ones.
• Expand surveillance coverage to potential breaches under REMIT Articles 3 and 4 (in addition to Article 5), across all markets and products.
• Enhance proactive engagement with market participants.
• Ensure timely and complete reporting of suspicious behaviour, focusing on effectiveness rather than formal compliance alone.

Read more.

For follow-ups by national regulators, ACER recommends: 

• Strengthening PPATs’ analysis of market behaviour by providing more detailed assessments of market participants’ conduct and its impact on the market.
• Further enhancing NRAs’ capacity (staff and IT resources) to manage the growing volume and complexity of cases.
• Maintaining and expanding engagement between NRAs and PPATs to further improve reporting quality.
• Ensuring timely communication with ACER to support effective coordination and case handling.

Read more.

What's next?

Don’t miss the ACER-European Commission REMIT event on 11 June. Register here.

ACER publishes its Opinions on requests from seven national regulatory authorities for derogations from applying EU gas network codes and guidelines at interconnection points with third countries. 

These requests have been submitted by the energy regulators of Bulgaria, Estonia, Hungary, Italy, Lithuania, Slovakia and Spain, and are addressed to the European Commission and ACER (in line with the Gas Regulation). 

The Regulation widens the scope of the existing EU gas network codes and guidelines, expanding their application to third countries’ entry and exit points, starting from 5 August 2026. 

If, for specific reasons (e.g. existing long-term contractual arrangements or legal difficulties in establishing a dispute resolution procedure with transmission network operators or natural gas suppliers established in third countries), the EU rules cannot be effectively implemented, national regulatory authorities can request a time-limited derogation.

What is the role of ACER?

ACER’s role is not to issue a recommendation nor to reject or grant a derogation – this is the task of the European Commission.

After receiving the derogation requests, ACER had three months to provide its opinion to the European Commission. To inform its decision-making process, ACER conducted an extensive review of each request, held bilateral discussions with the relevant national regulatory authorities and applied a harmonised approach while considering the specifics of every Opinion.

For the details of each country, see the full text of the individual ACER Opinion. In brief, ACER considers that in Hungary and Bulgaria the relevant network codes have been implemented to the maximum extent possible to date, until certain EU rules are not implemented simultaneously by the neighbouring transmission system operators.

For Estonia, Italy, Lithuania, Slovakia and Spain, ACER has carefully examined the requests and their specific conditions, providing detailed inputs to the European Commission to support the Commission’s decision.

What are the next steps?

The European Commission will decide whether to grant the derogations, taking into consideration the input provided by ACER.