Lisbon, April 9, 2026 (Lusa) - Power utility REN (Rede Electrica Nacional) announced on Thursday that it carried out the first issuance of guarantees of origin for biomethane produced in Portugal on 20 March at the Aljustrel production plant.

Biomethane, also known as Renewable natural gas (RNG), is a renewable fuel made from biogas that has been upgraded to a quality similar to fossil natural gas.

In a statement released on Thursday, the energy grid operator said that these documents certified the origin of biomethane produced by Capwatt at the Aljustrel Biomethane Production Plant, making REN the first entity to issue a production certificate for this renewable gas in Portugal.

REN explained that these certificates serve as proof to consumers that a specific portion of the energy they use was produced from a particular source and technology.

"In the case of renewable energy, these guarantees prove the origin of the energy, enabling suppliers and end consumers to demonstrate their consumption of renewable energy, particularly in the context of their sustainability strategies and respective obligations", the company said in the document.

REN highlighted that these guarantees of origin were particularly significant for biomethane as they ensured the traceability and valuation of renewable gases, promoting the decarbonisation of sectors where electrification is technically difficult.

JO/MYAL // ADB.

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