New biogas processing plant in Aarberg: Axpo supplies Energie Wasser Bern with biomethane

12.02.2026 - The fermentation plant operated by Axpo Biomasse AG in Aarberg (BE) is realigning its energy production: the previous combined heat and power plant has been replaced by a modern biogas processing plant. It produces biomethane from regional green waste, which is purchased by Energie Wasser Bern.

What it's all about:

• The Axpo Biomasse fermentation plant has replaced its combined heat and power plant with a modern biogas processing plant.
• Energie Wasser Bern (ewb) purchases all of the biomethane produced.
• The biomethane is fed into the local gas pipeline operated by Seelandgas AG. Gasverbund Mittelland (GVM) is building a pressure boosting station to feed any surplus gas into the high-pressure gas network.

The Axpo Biomasse AG fermentation plant in Aarberg processes around 20,000 tonnes of biomass from the region into electricity and natural fertiliser every year. Until now, the biogas produced in this process has been used on site in a combined heat and power plant (CHP) to generate electricity. This year, Axpo is realigning its energy production in Aarberg: the existing CHP plant has been replaced by a modern biogas processing plant.

Energie Wasser Bern takes over the entire production

The new plant processes the biogas produced into high-quality biomethane. This virtually CO₂-neutral gas can be used in the same way as fossil natural gas and fed directly into the existing gas network. Axpo Biomasse AG and Energie Wasser Bern have signed a contract for the complete purchase of the biomethane produced. By taking over production from the Aarberg plant, Energie Wasser Bern is increasing its share of Swiss biogas and thus contributing to the promotion of Swiss biogas production.

The gas is fed into the grid via the Seelandgas AG gas pipeline. A pressure boosting station is being built to enable the biomethane to also enter the GVM grid. The existing gas infrastructure at the Aarberg site enables the project to be implemented efficiently and optimally.

The switch from electricity production to biomethane feed-in allows for a more efficient use of the energy content of the biomass overall. ‘In this way, we are making another important contribution to the decarbonisation of energy supply and to regional value creation,’ says Daniel Gobbo, Head of Axpo's Biomass Business Unit.

‘By purchasing energy from the Aarberg plant, ewb is consistently pursuing its strategy for a CO₂-neutral energy future and strengthening sustainable security of supply,’ says Marcel Ottenkamp, Head of Energy Management at ewb.