In the new buildings, almost only LED systems are now being designed. The majority of existing plants, on the other hand, have not yet been converted to LED technology and hold great and often easy-to-develop climate protection potential: so-called “Low Hanging Fruits”. In the conversion forced by the phasing out of fluorescent lamps (e.g., in the EU this year, 2023), the main question is whether “transitional solutions” in the form of LED replacement lamps make sense or whether it would be better to switch to more powerful LED lights right away. However, the focus of renovations is not solely on the high efficiency of the LEDs. New control options should also be considered wherever possible in coordination with the most sustainable light source, daylight. In addition, the understanding of user needs has evolved in recent years [1], so that, with proper planning, renovations also ensure an improved and performance-enhancing quality of stay with increased visual comfort in rooms.