Bio-methanization

Since 1st April 2009, all waste food products from UNIL restaurants and cafeterias have been taken to Les Saugealles Farm to be turned into biogas. A clean and economic initiative!

Thanks to an agreement between the UNIL and Lausanne Municipal Cleaning Department, leftover food and coffee grounds from the campus’s cafeterias and restaurants are now used to make biogas. This natural gas is then burned by an installation that produces green electricity for around 100 households in Lausanne.

An economic and clean solution
Previously, slops were fed to pigs and coffee grounds had to be incinerated. These solutions were costly and of doubtful benefit to the environment. The biogas production plant is environmentally-friendly and brings down the cost of waste disposal. By delivering 10 to 15 tonnes a year, the UNIL will use at least 10% of the absorption capacity for slops at Les Saugealles Farm.

Les Saugealles Farm, pilot installation
In service since February 2007, the biogas installation at Les Saugealles farm, located in the Jorat district of Lausanne, is a pilot experiment run by the Department of Forestry, Farming and Wine-Growing and Lausanne Industrial Services.

Mixed with manure from the farm’s cows and horses, slops, grass and frying oil are kept for 44 days in a 400m3 "digester", maintained at a temperature of between 35 and 42°. This produces gas which fires a cogenerator to produce electricity and heating, and also the "digested product" (2,000 tonnes/year) which is an excellent fertilizer for use on the farm.
 

Schéma du dispositif des Saugealles © SIL Lausanne