The following master’s thesis examines the use of biothermal energy released during the decomposition process of composting. The aim of this thesis is to explain the heat generation principles of composting, to summarize its consumption possibilities, and to design a suitable use of the source for the demands of a real building. First, the theoretical framework compares various options of the biomass utilization. It then describes the biochemical course of organic matter decomposition, and conceptualizes the term thermocompost as well as different methods of heat extraction. Subsequently, it lists ways of applying this technology in practice. Second, the empirical part uses the findings to propose a compost pile installation, and its connection to the current heating and hot water system in Ecocentre Karpaty in Nová Lhota, Hodonín. Due to the low-temperature nature of the source and the mode of usage of the building, it is recommended to accumulate the heat generated in the hot water storage tank. The preheating of potable water is considered as its primary benefit. In case of sufficiently high temperature of the thermocompost, the design also includes the possibility of preheating of heating water. In conclusion, the thesis evaluates the financial costs of the project and determines the financial savings. These have – due to the low frequency of the building usage and the consumption of hot water reach – relatively low values.