DesignLights Consortium Updates its Technical Requirements for LED-Based Horticultural Lighting

Hort Version 4.0 further supports and speeds adoption of energy efficient lighting and controls in the controlled environment agriculture industry.

MEDFORD, MA – March 12, 2024 –A new version of the DesignLights Consortium’s (DLC) Horticultural Lighting Technical Requirements released today strengthens efforts to improve the efficacy and quality of LED products used in the controlled environment agriculture (CEA) industry.  

Taking effect April 18, 2025, the DLC’s new requirements come at a time of burgeoning growth in the CEA sector. Valued at $7.8 billion last year, the global CEA market is expanding at a compound annual growth rate of 12.2 percent and expected to reach $22 billion by 2033, according to a February 2025 market research report. With lighting being the largest operational expense in CEA facilities, there are significant opportunities to increase energy efficiency and cost savings with the right lights.  

“Fueled by demand for locally produced food as well as the legalization of cannabis cultivation in many states, CEA has consistently grown since we launched our horticultural lighting program in 2018,” DLC Executive Director and CEO Christina Halfpenny said. “The efficacy and quality requirements for fixtures on our Horticultural Qualified Products List (QPL) have steadily increased, as well. Hort V4.0 continues this trend as we seek to promote energy efficient technology to deliver energy savings and support decarbonization goals.”  

Relying on industry standard nomenclature, testing and reporting methodologies, the DLC’s horticultural Technical Requirements establish minimum performance thresholds for horticultural LED fixtures. Since the DLC began its horticultural lighting program, the average efficacy of listed products has increased by nearly 25 percent. Meanwhile, the list itself has increased at an annual rate of over 102 percent. As of February 2025, the Hort QPL comprised more than 1,200 products from over 130 manufacturers. 

Released as a draft for stakeholder comment in November 2024, V4.0 is the product of collaboration among many stakeholders in the horticulture industry. The Technical Requirements support the acceleration of energy efficient lighting in CEA through three key updates: 

• Increasing the photosynthetic photon efficacy (PPE) threshold of DLC-listed horticultural lighting products by 8.7 percent compared to Hort V3.0, which will result in listed fixtures that are at least 45 percent more efficient than the most efficacious non-LED horticultural lighting option – the 1,000-watt double-ended high pressure sodium luminaire;  

• Removal of lamps as categories eligible for QPL listing – a decision based on low application numbers in lamp categories and no comments during the V4.0 draft comment period requesting maintaining lamp eligibility; and  

• Clarifications to various requirements, including for certain product testing requirements and definitions of key terminology. 

Horticultural lighting manufacturers currently on the QPL are encouraged to start submitting applications to update V3.0 to V4.0 listings starting April 18, 2025. 

The DLC is confident this latest version of its Horticultural Lighting Technical Requirements will help accelerate widespread adoption of LED technology that is both energy efficient and optimal for cultivation in CEA facilities. For more details, view the full policy update here and register for an informational webinar on March 25.