Optimizing efficiency and material use in lighting systems through industrial LVDC-based energy distribution

Since the late 19th century, electric lighting has significantly improved human comfort, becoming essential indoors and outdoors. However, it now accounts for 15-19% of global electrical energy demand, leading to high operating costs and CO₂ emissions. Modern lighting systems, especially those using light-emitting diode (LED) technology, offer advantages in energy efficiency, service life, and recyclability. Despite this, conventional alternating current (AC) energy distribution has seen little change. Most LED lights still rely on AC input but internally convert it to direct current (DC), typically using individual ballasts for rectification and voltage adjustment – resulting in system losses. This study investigates losses in current lighting supply systems and proposes decentralized DC grid concepts to power lighting more efficiently and support renewable energy integration. The proposed architecture achieves over 6% annual electrical energy savings and more than 14% material savings over an LED system’s lifetime. To enable safe implementation, various switching and protection concepts were developed for both earthed and isolated grid branches. Losses from protection components were measured and compared to a standard AC-based solution. Based on installation and customer requirements, an implementation plan is recommended. The concept is transferable to commercial, private, and public lighting systems and other light sources.