The subject of the project is the modernisation of energet. 3 buildings of public utility, with a useful area of buildings which have undergone thermal modernisation of 10337.31 m² belonging to the Municipality of Ostrowiec Św., i.e. The City Hall (modern. parts of the central heating system, valve assembly; insulated parts of the roof, roof, exterior wall; introduction of heat recovery from ventilation, cooling function, mechanical ventilation with heat recovery together with control panels, automation and control on parts of the building; replacement of door parts; installation of PV installations; replacement of parts of window joinery or glazing; moder. lighting parts on energy-saving with sensors and wiring), Environmental Self-Aid House “Hailborne” (modern. central heating installation, valve assembly; insulated. basement walls, exterior, ground, roof; replacement of window and door joinery; moder. lighting on energy-saving), Cinema Etiuda (modernisation. c.o., valve assembly; intestinal. stropodachu, ceiling under the attic; replacement of door and window joinery; installation of solar collectors for the purpose of crevice replacement; installation of PV installations; introduction of heat recovery from ventilation, cooling function, mechanical ventilation with heat recovery, ventilation units with automation and control; moder. lighting on energy-saving with sensors and wiring as part of another project). The project assumes the installation of the shutdown of new unused elements. The aim of the project is to increase the energy efficiency of public buildings and the residential sector. As a result of the implementation of the project: electricity saved (129,57 MWh/year) and heat (5 113 GJ/year), reduced primary energy consumption in public buildings (2343864 kWh/year) and final energy consumption (5 674 GJ/year). In addition, the project will result in an annual decrease in greenhouse gas emissions of 600.3 tonnes of CO2 equivalent and the number of RES electricity generating units built will be 2 pcs.