The diploma thesis (DP) deals with the issue of economic efficiency of biomass use in a selected company. Its aim was to analyze and evaluate the economic efficiency in the production of energy from fossil fuels and biomass, and to compare their basic economic parameters. The company, which previously used natural gas for heating, has been heating with wood dust since 2010, and in our diploma thesis we analyzed how much they saved by no longer using natural gas as the main fuel for heating production. We evaluated the economic efficiency. Based on this, heat production alternatives were modeled, which are then evaluated and compared with reality.