Bioenergy is energy that is obtained from biomass (entire organic substances). Until now wood as a solid fuel has been very important but in the last years the agricultural products and organic remnants has become increasingly relevant for the energy supply. The sun is the basis for the biomass energy. The solar energy is chemically absorbed, with the help of the photosynthesis, in the plants. In Kötschach-Mauthen we have three district heating grids. The energy concept of the community shows that the biomass has high potentials to grow. The district heating plant heats all public buildings of the community (townhall, schools, public swimming pool etc.). The whole raw material for the biomass plant comes from the local area.
A biogas plant uses the fermentation of biomass to produce biogas. The raw material of agricultural biogas plants is liquid manure and silage. The by-product of the process is called digestate this is used as a fertilizer. Most biogas plants appropriate the produced gas in a cogeneration unit to generate electricity and heat. In Würmlach there is the biogas plant of the AAE. The specific characteristic of this plant is the combination with the district heating plant “Obergailtaler Fernwärme”. A two kilometre long gas pipeline transports the produced gas to the 500 kW biogas motors located at the “Obergailtaler Fernwärme”, which heats the return flow of the district heating plant with a heat exchanger. In the interims period this combination enables to stop the 1.500 kW biomass boiler, hereby it is possible to save a lot of biomass.