The theoretical biogas potential Pt was calculated taking into account conversion factors of livestock heads into Livestock Units LSU (500 kg) [64]—for cattle the conversion rate is 0.8, for pigs—0.2, for poultry—0.004. The mean amount of slurry per 1 LSU is 44.9 kg for cattle, 43.5 kg for pigs and 26.8 kg for poultry [65]. The number of heads were taken from the data of the Central Statistical Office [66].