Wood biomass is a renewable source of energy, which is used in the process of cogeneration. Cogeneration is the simultaneous production of electricity and thermal energy in thermal power plants. The raw material is of low economic value and is available in significant quantities in the form of a solid substance of biological origin (trees, bushes) or as a by-product of wood processing in industry (waste wood, sawdust). The raw material does not need to be processed before use. Wood biomass thermal power plants are highly profitable due to the efficient thermodynamic use of fuel and are useful in reducing dependence on non-renewable sources for the production of electricity. Cogeneration will be presented with associated calculations and the principle of operation of the thermal power plant using the example of the woodchip cogeneration plant "Energana Županja". The advantages of wood biomass power plants compared to other ways of producing electricity are low greenhouse gas emissions, increasing energy independence by preserving fossil fuel reserves, stimulating the local economy and rural development in areas rich in forests and agricultural environments.