Views: 24 Author: Site Editor Publish Time: 2025-03-20 Origin: Site
US DLC Releases Official Version of Horticultural Lighting Hort V4.0
The U.S. DesignLights Consortium (DLC) officially released the Hort V4.0 standard for horticultural lighting on March 12, 2025, with an effective application date of April 18, 2025. Products that do not meet the new Hort V4.0 requirements will be delisted from the Qualified Products List (QPL) by January 5, 2026. The application deadline for Hort V3.0 was April 17, 2024, and the deadline for upgrading from Hort V3.0 to Hort V4.0 is October 31, 2025, with no automatic upgrades for products.
The DLC Horticultural Lighting Technical Requirements aim to further support and accelerate the adoption of energy-saving lighting and controls in Controlled Environment Agriculture (CEA), guiding the industry toward sustainability and decarbonization efforts.
Update 1: Increased Photosynthetic Photon Efficacy (PPE) Requirement
Hort V4.0 raises the PPE threshold to 2.5 µmol/J (with a -5% tolerance), an 8.7% increase from the 2.3 µmol/J in Hort V3.0. This sets the DLC efficiency threshold for LED-based horticultural lighting over 45% higher than the most efficient non-LED options. The raised PPE requirement will remove the least efficient products from Hort V3.0 (approximately 11% of the QPL) from the listing. Manufacturers are advised to verify compliance early.
Update 2: Removal of the "Lamp" Category
The "lamp" category, which included linear tubes and E39 bulbs, has been discontinued. Since Hort V2.1, new certification pathways were introduced for DC-powered products, liquid-cooled products, and lamps. While other categories have seen active participation and QPL growth, the lamp category lacked adoption. With no comments supporting its retention during the review period, DLC decided to eliminate it in Hort V4.0.
Update 3: Clarifications on LM80 Reports, Tunable Spectrum Products, and Application Fees
LM80 Report Applicability: Additional clarification states that manufacturer declarations can be used for LEDs with the same peak or dominant wavelength. However, applications will be rejected if the nominal wavelength deviates by more than ±15 nm from the LM80 test wavelength.
Tunable Spectrum Products: Two new definitions are introduced—Customizable Spectra and Predefined Spectra—with updated testing requirements for each. It’s further clarified that the maximum power state may not necessarily involve all channels or LEDs operating at full capacity.
Application Fees: Starting April 18, 2025, certain Hort V4.0 application fees will increase to maintain rigorous evaluation standards and support enhanced QPL features for end-users. For upgrades to Hort V4.0 where product performance remains unchanged since the initial submission, a $500 non-performance-impacting update fee (per product family) will apply.
Upgrade Application Fees: For cases upgrading to Hort V4.0 with no performance changes, a $500 fee per family applies.
New Application Fees: Due to the significant efficiency improvements in V4.0, models not meeting the new PPE requirements should be identified and addressed promptly, as they will be delisted by January 5, 2026. This may involve product line adjustments, and manufacturers are encouraged to plan ahead, Expedited Application Fee: USD1650 per application.
