Electric lighting is crucial for the building energy performance of public building, including the educational ones. Electric lighting use is affected by various factors such as natural light availability, building envelope characteristics, and lighting system design. In Europe, lighting designers can use the Lighting Energy Numerical Indicator (LENI) to estimate the energy use for electric lighting. The LENI definition integrates parameters related to daylight availability and occupancy-based lighting control systems, among others. Several studies have confirmed that lighting control systems can reduce energy use by 15%–25%. This study examines the role of daylighting and lighting control systems for a fictional building representing a typical Swedish school that uses LED lamps. The LENICALC software developed by ENEA was used to calculate LENI. The findings highlight the significant potential for energy savings that can be achieved by integrating daylight and artificial lighting control systems.