Hungary’s biomethane network access: FGSZ adds Endrőd virtual entry and updates settlement arrangements

The notice implements a new distribution-system biomethane injection arrangement under the Hungarian gas system’s partial-island operation rules. Alongside the virtual entry, it changes two merged exit points and the gas-quality settlement arrangements for the 2026/27 gas year.^[2]

Under Hungary’s “partial-island” arrangement, a local distribution network receives gas from both a local producer and the national transmission network. It is not an isolated network: locally produced biomethane supplies part of demand, while transmission deliveries provide the balance.

To include that biomethane in the gas-market accounts, FGSZ records it as though it entered the transmission network and then exited into the local distribution network. These records are called the virtual entry and virtual exit. They represent measured gas quantities — not physical movement through transmission pipelines. The virtual exit is grouped with actual transmission deliveries into one combined accounting point, allowing suppliers to schedule deliveries and reconcile the quantities supplied to the area.^[3]

For example, suppose consumers use 100 energy units: 20 come from local biomethane and 80 arrive through transmission pipelines. The accounts show a virtual entry of 20 and a combined exit of 100. This records both sources consistently, even though only 80 units physically pass from transmission into distribution.

The Szarvas producer injects biomethane into MVM Égáz-Dégáz’s local distribution network. A connection between that network and OPUS TIGÁZ’s distribution network allows gas to flow into the OPUS area. The accounting arrangements therefore need to distinguish the quantities assigned to each area.

Endrőd II (Biometán) records the producer’s total injection. Two virtual exit records divide that quantity: Endrőd 1-T records the metered gas transfer into the OPUS network; Endrőd 1-E records the remainder allocated to the MVM area, calculated as total injection minus that transfer.^[4] For example, an injection of 20 energy units, with 8 units measured flowing to OPUS, leaves 12 units allocated to MVM.

Each area’s allocated amount is then added to its physical deliveries from transmission to calculate its combined supply record.^[4]

The partial-island rules do not provide for physical reverse flow from distribution into transmission within this arrangement. Commercial use of surplus production is limited accordingly; where planned production exceeds the area’s consumption, the rules require production to be reduced.^[3]

The investment implication is straightforward: annual gas demand is not enough to demonstrate year-round injection capability. Developers need to understand three things:

FGSZ’s own biomethane planning map recognises this issue by using injection information to help developers assess injection options.^[5]

Where an actual constraint is demonstrated, the appropriate response could be any of four options. The choice should follow a comparison of costs and usable additional capacity — not an assumption that every new virtual point needs new transmission assets.

The accompanying update to the MER, FGSZ’s gas-quality settlement framework, has direct commercial implications. MER specifies how gas volumes are converted into energy and how quality measurements are assigned to network points. For daily settlement, FGSZ uses weighted quality values derived from hourly quantities and quality data; merged points use quantity-weighted values from their constituent points.^[6]

When several sources supply an area, the accounting must reflect their respective quantities and energy content. Otherwise, the commercial allocation can diverge from the energy actually delivered.

The annual historical averages published in MER should not be confused with an unchanging daily settlement value. Nor does an accounting update relax gas specifications: FGSZ continues to identify the network user as responsible for injecting compliant gas.^[6]

The Szarvas terms address a specified case: a network user has both local and transmission supply, and local production exceeds its own customers’ demand but can be absorbed by other distribution consumers. For that case the terms set two booking requirements.^[4]

FGSZ conducted a non-binding domestic biomethane injection survey in autumn 2024. Its published results show submitted production plans reaching 33,942 m³/hour by 2030, translated into approximately 255 million normal cubic metres annually, assuming 7,500 operating hours per year.^[7]

That is a useful indication of developer interest and its geographic distribution. It gives network planning a more concrete starting point than a national ambition expressed without project locations.

The cross-border survey gives a more cautious signal. FGSZ’s separate survey launched in July 2025 asked specifically for biomethane transmission-capacity demand at EU border interconnection points. It was not another survey of all domestic production projects.^[8] In November 2025, FGSZ reported that it had received no biomethane demand indications in that exercise.^[9]

Read together, the two surveys suggest a distinction between domestic project interest and demonstrated demand for additional cross-border capacity. The prudent response is to develop infrastructure against credible, location-specific requirements rather than presume that domestic production announcements automatically justify export-oriented expansion.