5 things to know about California’s new energy codes

Dr. Nadia Sabeh, the president and founder of greenhouse consulting firm Dr. Greenhouse, says that California’s new energy codes offer both challenges and opportunities for growers in the state. Those same challenges and opportunities will apply to growers elsewhere too if the same or similar codes are adopted by other states.

“They mean growers have to pay attention,” Sabeh says. “And you’re going to have to make sure what you’re designing into your greenhouse and into your indoor farm comply.”

1. Here’s what they mean

According to Sabeh, there are measures in the new codes that apply to lighting, HVAC, building envelopes and power monitoring. The mandatory measures are listed out in Fig. 1. She also wrote about the codes in a blog, here bit.ly/dr-greenhouse-codes-blog

“What this really means is that it’s not a free-for-all,” Sabeh says. “You can’t just do whatever you want to do. And, in some cases, you can’t do what you think might be best for your crop. There are these trade offs with energy efficiency and plant quality or yield. I think that’s where most growers are concerned.”

An example Sabeh gives for a trade-off is the greenhouse envelope. The new codes require two layers of any cover you are going to use, be it glass, polycarbonate or another material. For growers, the concern would be if they are reducing the amount of light transmitted to their plants.

“‘Am I going to see reduced yields in my crops?’ is question number one,” Sabeh says. “And I definitely think that is a valid concern. A one percent increase in light usually translates to a one percent increase in yield. And if you switch to something that’s 80 or 85% transmission when you were at 90% transmittance, all of the sudden that might mean you have less yield.”

2. This only applies to new builds

California growers with an existing facility do not need to comply with the new energy codes, Sabeh says. They can keep growing how they have been without worrying about staying in line with new requirements.

“With an existing facility, you are grandfathered into the older requirements,” Sabeh says.

Anyone who received their building permit before January 1, 2023 is grandfathered into the other requirements, as well. However, that changes if they are planning an expansion, a renovation (i.e. installing a new HVAC system) or building a new structure from the ground up.

“You do want to become familiar with the energy code section if you’re considering a build,” Sabeh says.

In the design process, Sabeh says it’s also important to consider what will change with the new light requirements. For instance, if a grower uses supplemental lighting, they’ll need to make sure the lighting they plan on purchasing will fit requirements in a new build or expansion even if it’s lighting they’ve previously used.

3. What controlled environment horticulture means

In reading any literature or breakdown of California’s energy codes, the term “controlled environment horticulture” will appear. That term is used because the acronym ‘CEA’ was already taken by the California Energy Alliance.

If growers are searching the energy codes for information, they need to make sure they search “CEH” and not “CEA.”

4. Energy code changes are good for indoor ag

In the energy codes, CEH is defined as a process instead of a building type. That’s a good thing for growers, Sabeh says.

“In the California energy code, processes are defined as systems that don’t necessarily require human thermal comfort or don't have that as their primary [function],” Sabeh says. “So, for example, other processes covered in the codes include elevator machine rooms. So we have an elevator and their is a motor and that motor produces a lot of heat. So to prevent the motor from overheating in the room that it’s sitting in, there’s an air conditioning system to cool that elevator machine room down. The primary function of the elevator is to move people up and down the building and we are air conditioning the machine, not the people. So they are different requirements in terms of efficiency.”

Labeling CEH as a process, she says, shows that California understands that the space is not for human comfort, but instead for plant comfort.

5. Why this matters to other states

Other states, Sabeh says, will look at the energy codes in California and take notes when considering their own revisions.

What Sabeh expects is that the industry on the whole will adapt. Greenhouse suppliers, by working with growers in California, will gain the experience to meet those needs. That will then allow them to be prepared if and when similar energy codes spread to other states.

“I think that, if we demonstrate that having this lighting requirement in California doesn’t destroy the industry and maybe that benefits it, that would be a win,” Sabeh says. “Growers are so focused on quality and yield and sellable product. But what if sellable product decreases by 1%, but our savings in terms of operating savings increases by 10%? As long as growers can still meet market demand with that reduced 1%, but save 10% on the other side, then I think growers in other states will say that they want that, too. It’s not always about output. Sometimes it’s also about input.”