About Axpo Kompogas

Discover Axpo Kompogas

We make the best out of biowaste, turning it into renewable energy and natural resources for the future.

Biowaste contains carbon-neutral renewable energy. The fermentation process in one of our 15 Kompogas plants converts this biowaste into biogas and digestate containing methane. We take the biogas and produce electricity and heat or feed it into gas grids, while the digestate can be used as fertiliser, thus returning it to the fields it came from.

The closed Kompogas cycle

We have been sustainably recycling biowaste for over 20 years and have built up knowledge and experience across the board, from separating waste and collecting cuttings through to processing, energy production and digestate. By recycling valuable materials, we are closing gaps in cycles and generating energy and resources to serve generations. 

Fermentation plant

The ecological cycle in the Kompogas process

The Kompogas process is based on the continuous dry fermentation of biowaste in an oxygen-free atmosphere. This generates carbon-neutral methane, which is converted into green electricity and heat in a combined heat and power plant or treated to give the biogas the same high quality as natural gas. Tried-and-tested technology allows the Kompogas plants to extract as much energy out of the biowaste as possible: depending on the type of waste, a tonne of the material can generate up to 1000 kilowatt hours of energy, leaving around 900 kilograms of solid and liquid natural fertiliser as a by-product.

Transport and treatment

First of all, the Kompogas plant takes receipt of the biowaste that has been collected. It is unloaded in the underground silo, where an electronic crane moves it into the shredder, which breaks the waste down into a particle size of no more than 60 mm. After passing through the star screen, the shredded material is transported on a conveyor belt and through a spiral conveyor into the fermenter.

Fermentation inside the fermenter

The core component of the plant is the plug-flow fermenter, in which the fermentation process has to take place under uniform conditions. These are ensured by:

  • a sturdy agitator, which mixes the biomass with the microorganisms gently and continuously
  • keeping the fermenter supplied continuously around the clock in a fully automated process
  • the fermentation process inside the fermenter, which is based on anaerobic-thermophilic dry fermentation at a constant temperature of around 55 °C – ideal for microorganism growth.

The biomass remains in the fermenter for about 14 days. A temperature of 55 °C ensures that the material is safely sanitised and any weed seeds are killed off.

Mobile services

Shredding organic material

Sieving compost and soil and preparation

Transplanting compost heaps

Axpo Kompogas

Products and services

Our customers

Contact us

We’d be happy to advise you in person.

  • Eastern Switzerland

    Michael Schoch
    Sales Consultant Biomass Region East
    T +41 79 232 71 05  

  • Mittelland region

    Manuel Weber
    Sales Consultant Biomass Central Region
    T +41 79 922 73 76 

  • Zurich region

    Patrik Schmid
    Sales Consultant Biomass Zurich region
    T +41 79 461 76 99 

  • Western Switzerland

    Raphaël Bapst
    Responsable du service de la clientèle romande 
    T +41 79 935 61 12