The DesignLights Consortium (DLC) has released their Draft 1 Horticultural Technical Requirements V4.0. The draft proposes three updates: Efficacy increase: Hort V4.0 proposes to increase the efficacy threshold to 2.5 μmol × J-1, which is an 8.7% increase over the Hort V3.0 threshold. This will set the DLC efficacy threshold for LED-based horticultural lighting at more [...]