Controlled Environment Horticulture Prototype Workshop

In this workshop, the Statewide Codes and Standards Enhancement (CASE) Team will introduce a proposed building energy model prototype for Indoor Controlled Environment Horticulture facilities with high lighting intensities, such as indoor cannabis farms. This prototype is being considered for inclusion in the 2028 Alternative Calculations Methods (ACM) and the 2028 version of California’s Building Energy Code Compliance Software (CBECC).  Prototypes are also used as the standard design (baseline) model for the performance method of complying with Building Energy Efficiency Standards. The performance method provides flexibility to trade-off the energy performance of different components to achieve compliance. When a proposed design is modeled, compliance is demonstrated if the overall energy performance is equal to or better than the standard design’s performance.  

Agenda: 

• Welcome and Introduction  
• The Statewide CASE Team Role in building energy model prototype development 
• An introduction to the proposed Indoor Controlled Environment Horticulture (CEH) prototype for spaces that have lighting power density greater than 30 Watts per canopy square foot. 
• A discussion of proposed user inputs
• How to engage with the Statewide CASE Team and with the California Energy Commission regarding proposed building energy model prototypes. 

Building energy model prototypes represent typical building types within the state and incorporate minimum energy efficiency and load management requirements from California’s Energy Code (California Code of Regulations, Title 24, Part 6). The impact of proposed code change measures is evaluated in energy models of these prototype buildings, and statewide impacts of measures are estimated based on the statewide distribution of each building type by climate zone. These prototypes include general building characteristics, such as layouts and zones, and building envelope, and space-type specific characteristics, such as HVAC system, ventilation, lighting intensity, lighting schedules, occupancy schedules, plant transpiration schedules, temperature setpoint schedules, and humidity setpoint schedules. 

The proposed Indoor CEH building prototype will introduce new horticulture-specific space types, commonly found in high-lighting intensity indoor farms including cloning, vegetative, and flowering rooms for different stages of plant growth, as well as a plant drying room and a processing room for trimming, packaging, and other processing. 

The Statewide CASE Team receives feedback from the public and other stakeholders throughout the code-development process. Recent stakeholder feedback suggested that Indoor (<50% skylight ratio) CEH building permit applicants are using the existing prototypes, such as “Conditioned Warehouse” to show compliance via the performance path. However, none of the existing prototypes currently available in CBECC include the energy intensive process loads characteristic of indoor CEH buildings including rooms with lighting power density greater than 30 Watts per canopy square foot. To provide an option for the performance path that more accurately represents the loads in these facilities, the Statewide CASE Team, in conjunction with subject matter experts and a California Building Energy Modeling (CalBEM) Prototypes Technical Advisory Group, developed this Indoor CEH prototype. The assumptions were informed by field monitoring and data from cannabis farms throughout CA and the rest of the country. 

The Statewide CASE Team is requesting feedback on the proposed Indoor CEH building energy model prototype assumptions for indoor (<50% skylight ratio) CEH facilities that include a room with lighting power density greater than 30 Watts per canopy square foot. We invite participation from new and existing stakeholders.