The project will be implemented in the rural commune of Płońsk, in the Płońsk district. For the Municipal Public Use Building in Płońsk there will be a replacement of the existing heat source (gas boiler from 2009 with a heating capacity of 42 kW and low efficiency of heat generation 0.86) for renewable energy source (RES) – an air heat pump with a heating capacity of 29.3 kW and high efficiency of heat generation 4.1. The heat pump will be supported by a designed gas boiler with a heating capacity of 42 kW and a heat efficiency of 0.93.For most of the heating season, the primary and economical heat source for two buildings will be an air heat pump. During the peak period of heat demand or in the event of a failure of the basic heat source, the designed gas boiler will play a supporting role.The total efficiency of the production of the heat source is 3.6. The central heating system is designed to bring heat to individual rooms in the municipal utility building, covering heat losses by the building divisions and supplying the adjacent garage building with a partial change of use into the hygiene and sanitary rooms from the basic locker room.Because both in one and the other building there will be replacement of heating equipment (exchange of the gas boiler and replacement of coal boiler (goat), therefore modernising the thermal works. As a result of the replacement of the heating agent in the municipal utility building from the gas boiler to the heating agent powered from RES (air heat pump), the CO2 emissions were reduced by 82.00 % and dusts by 97.00 %.As a result of the replacement of the heating agent in the garage building with a partial change in use to the hygiene and sanitary rooms, the basic cloakroom from the coal boiler (goat) achieved a reduction of 100 % CO-fuel powered by the heating medium (RES).