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Agriculture, Codes + Standards

DLC Draft 1 Horticultural Technical Requirements V4.0

David Shiller December 26, 2024

 

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 than 45% above the most efficacious non-LED option.
  • Removal of lamp categories: Hort V4.0 proposes to remove eligibility for lamps. This decision was made based on low application numbers in lamp categories.
  • Clarifications to various requirements: A variety of clarifications are proposed throughout Hort V4.0, including for definitions of key terminology and for certain testing requirements.

The Draft 1 Horticultural Technical Requirements V4.0 document is available here. Stakeholder comments were accepted through 12/19/24.

 

author avatar
David Shiller
David Shiller is the Publisher of LightNOW, and Senior Business Development Consultant at Capacity Consulting, a North American consulting firm providing business development services to advanced lighting manufacturers. The ALA awarded David the Pillar of the Industry Award. David has been co-chair of the ALA’s Engineering Committee since 2010. David established MaxLite’s OEM component sales into a multi-million dollar division. He invented GU24 lamps while leading ENERGY STAR lighting programs for the US EPA. David has been published in leading lighting publications, including LD+A, enLIGHTenment Magazine, LEDs Magazine, and more.
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