Under the order of AB Šiaulių Energija, the feasibility study of the reconstruction of the southern boiler house was developed. The possibilities to install boiler houses of 20 MW, 30 MW and 40 MW capacity in the southern boiler house were analysed and the impact of these projects on the change in the price of heat was assessed. After the analysis, an optimal reconstruction plan of the southern boiler house by installing a boiler house of 20 MW was prepared. Investments in a new biofuel boiler of 20 MW were coordinated with the National Commission for Energy Control and Prices, and an application for funding from the Lithuanian Business Support Agency was prepared.