Higher Light Efficacy in LED-Lamps by lower LED-Current

About 20% of worldwide electric energy is consumed by lighting systems. LED-lamps in future have the biggest part and so it is important that they work with highest efficacy. With LED the energy wasting of traditional lighting technologies is obsolete. In 2015 in the households most LED-lamps less 25 watt at AC line voltage produce only 70 Lumen per Watt. Some small power filament LED lamps in bulb shape until 6 Watt give 120 Lumen per Watt. If we reduce the LED-current on the halve value we get a bigger efficacy of 150 Lumen per Watt. In the laboratory we get measurements of luminous intensity in an Ulbricht sphere in a temperature chamber from -20deg C to 60deg C. The presented measurement results verify this theory.