The presented contribution reviews actual status of biogas production in the European countries with a focus on the Slovak municipal WWTPs. In 49 monitored Slovak WWTPs (out of 520) the anaerobic digestion with biogas production is operated. The total volume of digestion tanks is about 195 000 m3 but the total daily biogas production is only approx. 55 000 m3 d–1. From a technological point of view, the digestion tanks have sufficient space for considerable increase of biogas production. The increase can be achieved by the choice and dosing of external organic sources that could bring significant energy – economic contribution to WWTP operation without technological process adaptation (plant oils, fats, organic materials, etc.) or with a small technological process adaptation (food residues, food and agricultural products and wastes). The contribution describes the actual load parameters of digestion tanks, specific biogas production, electrical power capacity, and production on the Slovak WWTP obtained on the basis of a questionnaire from Slovak Water Companies
