Biomethane in Bilbao's gas network: Enagás authorized to inject 475 Nm³/h

Key data

Metabarri SA now has the green light to discharge its biomethane production directly into the primary gas transport network in Bilbao. The Resolution of July 28, 2026 from the Directorate General for Energy Policy and Mines grants Enagás Transporte del Norte (ETN) administrative authorization, approval of the execution project, and declaration of public utility of the facilities necessary to make that injection possible.

This is not a pilot project or a test: it is an installation with a declaration of public utility, backed by a favorable CNMC report and without any objections during the public information period. The regulatory process has concluded without friction.

What does this regulation establish?

The resolution grants three simultaneous authorizations to Enagás Transporte del Norte for the facilities of the project called "Annex to the expansion project of the Arrigorriaga-Barakaldo, Barakaldo-Santurtzi gas pipeline (Arrigorriaga-Santurtzi Gas Pipeline Duplication) New position 45.01.DX.02 with Measurement Station G-65 for biomethane injection":

• Administrative authorization: legally enables the construction and operation of the new injection position.
• Approval of the execution project: validates the specific technical design of the installation.
• Declaration of public utility: allows ETN to act on lands and easements necessary to execute the project, with the advantages this entails in terms of access and expropriation if necessary.

The installation is integrated as an annex to the duplication of the existing Arrigorriaga-Santurtzi gas pipeline. The new position 45.01.DX.02 incorporates a Measurement Station G-65 specifically designed to measure and control the flow of biomethane entering the primary transport network.

The project did not require environmental impact assessment and received no objections during the public information period, indicating a clean procedure without opposition.

Economic and operational impact

For the renewable gas sector, this authorization has clear strategic value: it demonstrates that it is technically and regulatorily viable to connect biomethane production directly to the primary transport network in Spain, not just to local distribution networks.

The most relevant operational elements are:

• Injection capacity of 475 Nm³/h: this is the authorized ceiling for the installation. Metabarri SA will be able to inject up to that volume continuously into the ETN network.
• Pressure of 72 barg: operating at this pressure means that biomethane is incorporated directly at the primary transport level, not at secondary networks of lower pressure. This expands its potential distribution.
• Declaration of public utility: facilitates the execution of works and reduces the risks of blockage due to land access, which shortens construction timelines and costs.
• No environmental assessment: the project passed the screening filters without the need for a complete environmental procedure, which represents a saving of time and administrative costs for ETN and Metabarri.

For other biomethane producers, this case is a concrete reference for how to structure a connection request to primary transport infrastructure and which agencies are involved (Directorate General for Energy Policy and Mines + CNMC).

Who does it affect?

• Enagás Transporte del Norte, SL (ETN): directly authorized company. It must execute the project according to the approved design and operate the new injection position.
• Metabarri SA: biomethane producer that will be able to inject its production into the primary transport network through the new facility.
• Biomethane producers in Spain: this case is a direct precedent for any company evaluating connecting its plant to the gas transport network.
• Gas transport network managers: must know the procedural framework established by this type of authorization for future third-party requests.
• Investors and promoters in renewable gas: the authorization confirms that the Spanish regulatory framework allows and facilitates the integration of biomethane into existing infrastructure.
• Energy advisors and biomethane project consultants: reference for procedure, timelines, and agencies involved in similar projects.

Practical example

Metabarri SA operates a biomethane production plant in the Bilbao area. Until now, without direct access to the primary transport network, its distribution capacity was geographically limited. With the new position 45.01.DX.02 and the operational Measurement Station G-65, Metabarri will be able to inject up to 475 Nm³/h of biomethane directly into the Arrigorriaga-Santurtzi gas pipeline at 72 barg.

This means that on a full day of operation at full capacity, Metabarri can discharge up to 11,400 Nm³ of biomethane into the primary transport network (475 Nm³/h × 24 hours). That volume is distributed along with conventional natural gas circulating through the network, reaching industrial and domestic consumers connected to the Arrigorriaga-Santurtzi gas pipeline.

For a biomethane producer evaluating a similar project, this case shows that the procedure before the Directorate General for Energy Policy and Mines, with prior CNMC report, can be resolved without environmental assessment if the project meets screening criteria, and without objections if prior planning is solid.

What should companies do now?

1. Biomethane producers with plants in operation or in project: analyze whether their production and location are compatible with a connection to Enagás's primary transport network, using the technical parameters of this case as reference (475 Nm³/h, 72 barg).
2. Companies evaluating biomethane projects: identify which transport network manager operates in their area and contact them to learn about connection requirements. This case confirms that the Directorate General for Energy Policy and Mines and CNMC are the key agencies in the authorization process.
3. Energy project advisors: document this file (BOE-A-2026-17907) as a procedural reference for future requests for authorization to inject biomethane into the transport network.
4. Renewable gas investors: assess the regulatory precedent that this authorization represents for the viability of similar projects in other locations on the Spanish gas network.
5. Distribution network managers: review whether there are biomethane producers in their area who may be interested in similar connections at the distribution level, taking advantage of the framework that this resolution consolidates.

Official source

Consult complete regulation at official source

Disclaimer: This article is for informational purposes only and does not constitute legal advice. For specific decisions, consult a qualified professional. Source: https://www.boe.es/diario_boe/txt.php?id=BOE-A-2026-17907