The American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) has proposed new lighting efficiency standards for greenhouse and indoor controlled environment agriculture (CEA), updating Standard 90.1, the original energy-efficient requirements submitted in 2019.
According to a media advisory from the ASHRAE, the proposed regulations are similar to California’s recently adopted energy codes, which will go into effect for select cannabis operations beginning Jan. 1, 2023.
If the updated requirements are adopted by ASHRAE, they will only apply to newly constructed greenhouses or CEA facilities, additions to greenhouses or CEA facilities, and lighting alterations that replace 10% or more of horticultural luminaries in an enclosed space—only the newly installed lights must meet the updated requirements; lamp replacements are not considered an alteration, the advisory states.
The proposed code requirements are listed in the advisory as follows:
Horticultural Lighting Minimum Efficacy (indoor CEA lighting):
- For indoor CEA operations, luminaires with removable lamps will be required to use lamps with a photosynthetic photon efficacy (PPE) of at least 1.9 micromoles per joule.
- Luminaires without removable lamps shall meet a minimum luminaire PPE of 1.9 micromoles per joule.
- This will allow the use of efficient double-ended HPS lamps; most LED luminaires will qualify. The minimum efficacy requirements only apply to CEH spaces with more than 40 kW of aggregate horticultural lighting load. This equates to approximately (36) 1000W HPS luminaires.
- Time switch controls will be required for indoor horticultural lighting systems.
Horticultural Lighting Minimum Efficacy (greenhouse lighting):
- For greenhouses, luminaires with removable lamps will be required to use lamps with a PPE of at least 1.7 micromoles per joule.
- Luminaires without removable lamps will also need to meet a minimum luminaire PPE of 1.7 micromoles per joule.
- The minimum efficacy requirements only apply to greenhouse lighting with more than 40 kW of aggregate horticultural lighting load.
- Time switch and daylight availability controls will be required for greenhouse horticultural lighting systems.
Industry stakeholders are permitted to provide their feedback and comments on draft 90.1 until Oct. 24, and then it will head to the subcommittee for consideration.