This paper presents a project of energy efficient public institution lighting. An insight into the existing situation was obtained by field survey where the existing situation was recorded. The calculation of new lighting in the object was performed using the "Relux" program package and the results were presented in quantitative and qualitative form. Along with the calculation of lighting, a calculation of energy savings and CO2 emissions are made with the help of the algorithm for determining the energy requirements and the efficiency of the lighting system in the buildings. From the results of the lighting calculation, it is seen that the values achieved are required by the norm for interior lighting. The results of electricity savings and CO2 emissions are shown in tables showing that savings of 77% have been achieved in relation to the existing situation, which makes the replacement itself a viable one. In order to give an insight into the efficiency of the overall lighting installation, a calculation of the LENI lighting energy indicator has been made and the amount of 6.8 [kW /m2, year] was obtained. According to the estimated value of investment and electricity consumption, a return on investment of 13.3 years was obtained