A Review of Advances in Lighting Systems’ Technology—The Way Toward Lighting 4.0 Era

Research and development over the last century have historically concentrated on improving one specific aspect of energy efficiency. The market penetration rate for systems using solid-state light sources is currently between 40 and 45 percent, and it is rising. This article provides an update on the state of lighting technology based on the compilation of more than 160 recent documents. The only widespread use of solid-state lighting sources over the next years might help reduce greenhouse gas emissions by up to 500 Mtn per year and decrease electrical energy utilization for illumination by up to 4% by 2030. But this forecast could be severely affected by the “rebound effect.” Switching to the SSL2 concept, which consists of sustainable smart lighting systems based on solid-state lighting devices, might be one way to stop that harmful effect. Smart, human-centered lighting that incorporates light quality is driven by “appliance efficiency.” This merely suggests that the “Right Light” should be provided by next-generation lighting systems with the best levels of quality and efficiency when and where it is needed.