From biowaste to biogas: how to transform the resource into energy?

The discussions were led by various experts, including Camille Demazure, Delegate for Strategy, Development and Optimization (TRIFYL), Anne Bonrepaux, Director of Awareness-Raising for Public Policy Support (TRIFYL) and Véronique Velez, Head of the Innovation and Foresight Department, Project Management and Heritage Policies Department (USH).

With the entry into force of mandatory sorting of biowaste for all since January 1, 2024 (AGEC law), the management of these resources becomes an opportunity to reduce our dependence on fossil fuels and contribute to the energy transition. Thanks to recovery methods such as methanization, this organic waste can be transformed into biogas, a renewable, local and storable energy source to meet current ecological challenges.

Social landlords: key players in biowaste management

Social landlords are not responsible for processing biowaste produced by households, but they must manage it within the building and guarantee suitable systems for collection handled by local authorities.

Biowaste can have many uses: composting used in green spaces or urban farms, production of biogas through methanization or micro-methanization, this biogas being able to be used to supply the energy needs of residences.

With this in mind, many initiatives have emerged. For example, the Public Housing Office (OPH) of La Rochelle has installed 96 composting bins on 22 sites, involving 25% of tenants from the first year. This type of local management promotes the creation of social ties while contributing to the circular economy. Other landlords, such as Logéal immobilière in Seine-Maritime, have opted for methanization with innovative biowaste collection systems: tenants have bio-buckets and access to a "GaïaBox". This collected biowaste is then transformed into biogas used locally. In Marseille, as part of the call for projects "Social housing committed to green gas" led by GRDF and the Union sociale pour l'habitat, Erilia currently purchases 10% of its gas under a Guarantee of Origin and wishes to take a new step by producing green gas as part of micro-methanization, from its tenants' biowaste.

For Véronique Velez, Head of the Innovation and Foresight Department at USH: “Biowaste can help reduce our dependence on fossil fuels and is part of the answer to the energy and carbon issue.”

Tryfil: a player committed to the recovery of biowaste

One of the most inspiring examples of biowaste recovery is that of Tryfil, a public establishment for the recovery of household and similar waste from Tarn, Haute Garonne and Hérault, engaged in methanization to convert organic waste into renewable energy.

Created in 1999, Trifyl covers 358 municipalities or nearly 330.000 inhabitants in the Tarn department. A true regional project, Tryfil implements pioneering and exemplary initiatives in the management of biowaste by combining awareness-raising actions and sorting of biowaste at source. Users deposit their biowaste in an "orange bag" collected in the same bin as traditional black bags, which simplifies the sorting process by households and avoids additional collection costs for biowaste. Marked with a code detectable by camera to identify their origin by community, these bags will follow a separate route in the industrial unit and will be directed towards a methanization process, thus contributing to the production of biogas.

For Camille Demazure, Delegate for Strategy, Development and Optimization at Trifyl: "Trifyl aims to manage 8.000 tonnes of biowaste, or 20 kg/person/year. By combining the production of biogas from household waste and biowaste, this ultimately represents the production of a quantity of biogas equivalent to more than 10% of the gas needs of households in the area."

For Jean-Charles Colas-Roy, Chairman of Coénove: "Biowaste, sometimes seen as worthless waste, is now recognized as a valuable energy resource. Thanks to technological advances and innovative practices, this household waste is transformed into green gas and allows us to heat our homes using increasingly efficient boilers. Biogas is more than ever the emblematic energy of the circular economy and territories. We are proud to support and highlight innovative players such as TRIFYL or USH who are working to make the most of biowaste by producing green gas, a local, storable and renewable energy."