The subject of the project is a comprehensive energy renovation of the part of the large-area building of the Opole Rehabilitation Centre in Korfantów Sp. z o.o., i.e. swimming pool and gym. The decision to implement the project was made due to the technical condition of this part of the facility, high operating costs and insufficient thermal comfort. The energy audit shows that the building covered by the project generates large heat losses, i.e. it is characterised by low insulation of external partitions, poor condition of window and door joinery, inefficient internal lighting and ventilation system. The project envisages carrying out an energy audit before and after the project, preparation of construction documentation, supervision of the investor, thermal modernisation works including insulation of external and foundation walls, replacement of window and door joinery, insulation of the roof of the gym and the ceiling of the swimming pool hall, installation of heat pump, photovoltaic installation, mechanical ventilation of the swimming pool and gymnasium, modernisation of lighting and execution of works inextricably linked to the project. The energy modernisation of the facility where hospital treatment activities are carried out is in line with the current Health Needs Map. As part of the project, the following products will be produced: number of energy upgraded buildings – 1 pcs, number of RES heat generation units built – 1 pc, number of RES electricity generation units built – 1 pcs, additional capacity to generate heat from renewable sources – 0.18 MWt, additional capacity to generate electricity from renewable sources – 0,04495 MWe, number of modernised heat sources – 1 pc, usable area of buildings subjected to thermal modernisation – 1 709.71 m².