Skip to content
Briefings are running a touch slower this week while we rebuild the foundations.See roadmap
European Energy Markets
1JUN

ACER calls EU gas congestion normal

4 min read
08:52UTC

ACER's 29 May report framed a 'new equilibrium': congested network sides down to about 24 from roughly 50 in 2022, revenue stabilised near EUR 140m. The spot hub basis tells a different story.

← Back to Germany's TSOs call the refill model deadJump to analysis ↓
EconomicDeveloping
Key takeaway

The choke point has moved from pipeline capacity to storage volume, where ACER's healthy-network metric does not look.

ACER, the EU Agency for the Cooperation of Energy Regulators, published its gas wholesale congestion report on Friday 29 May and framed a "new equilibrium". 1 Contractually congested network sides have fallen to around 24, down from roughly 50 at the 2022 crisis peak, and congestion revenue has stabilised near EUR 140m. On the regulator's metric, the European pipeline network has normalised.

That institutional read collides with the spot signal. ACER's own winter analysis put Central European hub premiums above EUR 2/MWh over TTF , the Dutch Title Transfer Facility that prices the European benchmark. A basis that wide says delivered gas east of the benchmark still costs more than the headline. Both readings hold because they measure different things: congestion revenue prices the pipe, while the hub basis prices the molecule arriving where it is needed.

The reframe matters for where risk now sits. Falling congestion revenue and a stable network describe interconnection that allocates capacity efficiently. A persistent delivered-cost premium over TTF describes a market where the squeeze has migrated from how much gas can flow to how much can be stored. With pipeline capacity no longer binding, the structural choke points are the 17 June EU pipeline-supply cliff, which Hungary and Slovakia are litigating at the Court of Justice of the European Union , and the autumn storage landing, not the network ACER has declared healthy.

Deep Analysis

In plain English

ACER is the EU's energy market watchdog. On 29 May it published a report saying gas pipeline congestion across Europe has improved considerably since the 2022 crisis: down from roughly 50 problem points to about 24, with revenue from constrained pipelines stable at EUR 140 million. That improvement covers only one type of constraint: instances where a specific pipeline border point was overbooked. Europe has built more import terminals on its western coast since 2022, so overbooked border points have genuinely fallen. A different type of constraint has grown at the same time: underground gas storage east of the main hubs is under-filled, so gas delivered to Hungary, Slovakia or Austria costs EUR 2 or more per megawatt-hour above the benchmark Dutch price, even when the pipelines themselves are not overbooked. ACER's own winter analysis documented this premium; its congestion report did not flag it as a contradiction of the 'new equilibrium' claim.

Deep Analysis
Root Causes

Congestion revenue (EUR 140m) and congested network sides (~24) both measure the same thing: instances where capacity at a specific physical border point was oversubscribed and capacity had to be auctioned, generating revenue. This metric was designed for a pipeline-dominated gas market where the binding constraint was throughput capacity at physical interconnectors.

The structural shift since 2022 is that European gas supply has re-centred on western LNG entry points (Zeebrugge, Montoir, South Hook, Eemshaven, Revithoussa) rather than eastern pipeline entry points (Baumgarten, Velke Kapusany). LNG enters western hubs cheaply. The binding constraint now sits not at getting gas into western hubs but at getting gas from those hubs to Central European storage and end-use markets.

Central European hub premiums above EUR 2/MWh over TTF (Hungary EUR 123.23/MWh day-ahead on 12 May, per ) reflect a locational basis that is storage-volume-driven rather than pipeline-capacity-driven: there is insufficient stored gas east of the Alpine-Carpathian arc to buffer seasonal demand swings at Central European hubs, and the TTF-indexed contract structure of much Central European supply means buyers pay TTF prices for gas that costs EUR 2/MWh more to deliver physically.

Congestion revenue counts oversubscribed border-point capacity auctions. It does not count the locational spread between a western hub price and an eastern delivered-gas price when no single pipeline interconnector is the bottleneck; when the bottleneck is distributed across multiple storage sites and entry routes simultaneously, the congestion metric registers nothing.

Escalation

The ACER 'new equilibrium' framing is bureaucratically stabilising but analytically premature. The structural bottleneck has migrated rather than resolved. With the 17 June pipeline ban approaching and Hungary and Slovakia litigating at the CJEU, the basis premium above EUR 2/MWh is the forward indicator to track: a widening past EUR 3/MWh would contradict the equilibrium framing within weeks of the report's publication.

What could happen next?
  • Risk

    ACER's 'new equilibrium' framing may reduce political urgency for further network investment or storage mandates in Central European member states, leaving the locational basis premium structurally unaddressed through the 2026-27 winter.

    Medium term · Assessed
  • Opportunity

    Short TTF, long CEGH or PSV is the structural basis trade the storage-volume constraint supports; 17 June pipeline ban and Hungary/Slovakia CJEU challenge are the near-term catalysts for basis widening.

    Short term · Suggested
  • Precedent

    ACER's failure to update its congestion metric to capture storage-volume locational basis sets a precedent for the 'new equilibrium' framing surviving regulatory scrutiny even as physical market premiums contradict it; a measurement-framework gap that could persist until the next winter stress event.

    Long term · Assessed
  • Consequence

    Central European industrial offtakers on TTF-indexed contracts face delivered-gas costs EUR 2/MWh above the headline benchmark in a market the regulator has framed as normalised, reducing the likelihood of contract renegotiation or regulatory relief in the near term.

    Short term · Assessed
Sources:ACER
Mentions:TTF →Hungary →Slovakia →European Council →European Council on Foreign Relations →Gazprom →Florence →ENTSOG →Ukraine →Austria →European Union →Council on Foreign Relations →ACER →
First Reported In

Update #14 · Germany's TSOs call the refill model dead

ACER· 1 Jun 2026
Read original →
Causes and effects
Caused by
Central EU hub premiums top EUR 2/MWh above TTF
ACER's own prior winter analysis finding Central European hub premiums above EUR 2/MWh over TTF directly contradicts the new-equilibrium framing in the 29 May congestion report.
Occurred 27 May 2026
Read story →
This Event
ACER calls EU gas congestion normal
On the regulator's pipe metric the network has healed, but a persistent Central European premium over TTF shows the binding constraint has moved from interconnection to storage volume.
Led to
FNB Gas calls refill model broken
ACER's congestion report reframing the bottleneck as storage rather than pipeline capacity means FNB Gas's zero-booking evidence lands in a market where the structural constraint has already migrated to storage volume.
Occurred 27 May 2026
Read story →
Different Perspectives
Amsterdam-Rotterdam-Antwerp gas trading desks
Amsterdam-Rotterdam-Antwerp gas trading desks
TTF failing to sustain EUR 47-plus with 51 mcm/day of Norwegian supply offline confirms EUR 50 as a diplomatic ceiling rather than a physical floor; the curve is priced as a Troll-restart long, not a storage-deficit short. Winter Cal-26 long versus summer TTF short is the structural position FNB Gas's broken-mechanism verdict supports.
European Commission and DG Energy
European Commission and DG Energy
The Commission lowered the mandatory fill target from 90% to 80% and published the 11 May ETS benchmark revision saving industry EUR 4 billion, choosing industrial competitiveness over storage ambition at the moment physical injection margins narrowed. Berlin's confirmation of no summer injection scheme came with no Commission counter-instrument.
Hungarian and Slovak industrial offtakers
Hungarian and Slovak industrial offtakers
Hungary and Slovakia pay a EUR 2-plus delivered-gas premium over TTF benchmark prices regardless of ACER's improved pipeline-congestion reading, and both are litigating the 17 June EU pipeline ban at the CJEU (ID:3229). A post-17 June tightening of TurkStream supply would widen that basis further.
EBN and Dutch state
EBN and Dutch state
The Dutch state trebled EBN's mandate from 25 to 80 TWh, leaving EBN the sole active Dutch injector after the January auctions drew zero commercial bookings (ID:3637). The EUR 233m state budget cap is the binding cost ceiling; above-market injection at EBN is a fiscal transfer, not a market outcome.
CRE and French gas operators
CRE and French gas operators
France's 100% mandatory CRE booking order is carrying French injection regardless of the inverted strip, providing EU aggregate cover that Germany's abolished levy cannot supply. The order renews annually on CRE decision, making it a political risk rather than a structural guarantee.
FNB Gas and German TSOs
FNB Gas and German TSOs
FNB Gas formally declared the market-based storage-refill framework broken on 27 May, citing zero-clearing January auctions, ten days after Berlin ruled out any summer injection scheme. The intervention sets the institutional predicate for reintroducing a storage levy; the Gasspeicherumlage precedent (2022-25) confirms the administrative path is open.