The DLC is pleased to release the following draft update to the Technical Requirements for Horticultural Lighting as Version 2.1. This proposed update adds additional eligible product types to the Technical Requirements, with a proposed effective date of July 1, 2021. Please submit all comments using the V2.1 Comment Form to by Friday, November 20, 2020.

DRAFT Technical Requirements for LED-based Horticultural Lighting V2.1

In response to DLC member and stakeholder input, V2.1 proposes establishing eligibility for three new product types to the DLC Horticultural Lighting Program. To support the qualification of fixtures that enable greater whole facility energy savings by removing excess heat from the grow environment, among other strategies, the DLC is proposing Technical Requirements specific to externally-supplied actively cooled and DC-powered fixtures. Additionally, to facilitate the transition period from traditional light sources which rely heavily on lamp replacements, to a future state in which horticultural fixtures are adopted, the DLC is proposing adding eligibility for LED replacements for linear fluorescent and HID lamps.

While no new requirements are added for existing products, proposed requirements specific to the new product types are included in V2.1 under the “Special Considerations” section of the policy document.  New language is highlighted in the draft to indicate additions for ease of review.  

  1. Externally-Supplied Actively Cooled Horticultural Fixtures
    The DLC defines externally-supplied circulating-liquid cooled horticultural fixtures to be products in which liquid, often water or a water/glycol solution, flows through input and output ports of each fixture in the system, being channeled through a cooling plate or other heat exchanger within the fixture. V2.1 describes how to test and report on these types of products to ensure comparable performance to typical V2.0 listed products.
  2. DC-Powered Fixtures
    Horticultural lighting fixtures powered by direct current (DC) being considered by the DLC include modular fixtures, where one AC-to-DC power source supplies power to multiple fixtures, and fixtures that operate on DC power, where one or more AC-to-DC power source may or may not be sold with the fixture. V2.1 describes how to test and report on these DC-powered fixtures in place of the typical equivalent AC testing and reporting.
  3. LED Replacement Lamps
    V2.1 considers eligibility for two types of horticultural lamps: LED replacements for linear fluorescent lamps and LED replacements for mogul-base high intensity discharge (HID) lamps. Draft 1 proposes that LED replacement lamps for horticultural applications meet Horticultural V2.0 Technical Requirements and meet the definitions, eligibility requirements, and supporting documentation details of their respective policies under the DLC’s solid-state lighting program.

Comment Form

The DLC is seeking stakeholder input through the Horticultural Lighting V2.1 Comment Form before releasing Draft 2 of the V2.1 requirements in March 2021. Please submit all comments using the V2.1 Comment Form to by Friday, November 20, 2020.

Informational Webinar

The DLC will host an informational webinar on Monday, October 26, 2020 from 1:00 – 2:00 pm ET to review Draft 1 of Horticultural Technical Requirements V2.1.

If you have questions about Draft 1 of Version 2.1 of the Horticultural Lighting Requirements, please contact