Loss of Energy and Economic Potential of a Biogas Plant Fed with Cow Manure due to Storage Time

The aim of the publication was to analyze investments in biogas plants with a cogeneration unit for an average size dairy farm. The basis for the calculation was the use of cow manure as the only substrate in methane fermentation. The economic balance also includes ecological and service aspects. The study also shows how much energy and quality potential is lost due to improper manure management and what impact a single farm with dairy cows has on the emission of carbon dioxide equivalent. It has been estimated that as a result of improper storage of manure, even 2/3 of its fertilizing, energy and economic value can be lost, while causing damage to the environment. It has been estimated that for a single farm with 100 cows, without government mechanisms subsidizing investments in RES, the payback period exceeds 15 years, and the Return of Capital Employed is slightly more than 6%.