This paper presents a lighting control system based on natural light monitoring and on occupancy control, characterized by installation easiness, even for existing plants, and cheapness. The system is based on a smart control unit and lighting control devices that can be directly mounted on the lamps in series connection. The installation is noninvasive and does not require any changes in the wiring system, since the communication between each lamp and the control system is realized by means of a 2.4 GHz wireless protocol. The system functionality is ensured with any lamps, also with non-dimmable ones. Tests and functionality verifications on the system were performed in laboratory, proving the applicability to real cases and performances that are comparable to the ones achievable with dimmable LED lamps, but with a significant cost saving. Hypothesizing the application of the proposed system and of different control technologies and strategies to a real academic classroom case study, different lighting scenarios have been simulated. Obtained results allow quantifying the effects in terms of energy consumption and CO2 emissions relative to such scenarios, achieving up to 69.6% of energy saving and 30.5% of CO2 emissions avoided. From an economic point of view, the comparison between the proposed control system and commercial systems shows a shorter PayBack Period, from 9 to 5 years. (C) 2017 Elsevier B.V. All rights reserved.