Lighting, A Significant Horticulture Expense

When Dani Luna-Fuller joined US Lighting Trends’ staff as a contributor her first article was titled “Horticulture Lighting – It isn’t all Cannabis!”

Since then, she has authored a number of articles explaining the role lighting play in supporting horticulture.

But yes, cannabis is a part of horticulture. More importantly, it is possible to learn how lighting that benefits cannabis can also benefit other types of crops and plants.

Recently Cannabis Business Times (yes, there is a publication for everything), had an article on the topic. The article, authored by Robert Eddy, a resource efficiency horticulturist at the Resource Innovation Institute, is titled “Cannabis Lighting and Irrigation: Resource-Efficient, Cost-Saving Best Practices.”

With more states legalizing cannabis but, more importantly, horticulture lighting representing an opportunity, there are some best practices that all can learn as distributors, contractors, and lighting designers seek to serve / benefit from this market.

While the article focused on lighting and irrigation, here is the pertinent elements tied to the lighting market:

“Cannabis growers who can grow their crops to their desired quality and yield targets using fewer inputs (i.e., grow at a lower cost) than their competitors have a competitive advantage in their markets. And should the U.S. Food and Drug Administration approve cannabis for interstate commerce under federal rescheduling, competition would only get stiffer.

That’s why it’s important to take a close look at key systems such as lighting and irrigation to determine what, if anything, can be optimized to minimize potential waste and increase efficiency.

Here, we offer tips and best practices to help you grow a climate-smart cannabis business built for longevity.

Lighting, a Significant Expense

Lighting is one of the most significant operational expenses in cannabis cultivation, making it a prime area for resource-efficient and cost-saving initiatives. By optimizing lighting systems, growers can reduce energy consumption, improve yields, and ultimately boost profitability.

Mikhail Sagal, a contributor to Resource Innovation Institute’s (RII) Lighting Best Practices Guide and president of TSRgrow, an RII-member organization, says that the first thing cannabis growers need to do on their optimization journey is track their energy usage. Too often, growers set up their lighting systems without ongoing verification, leading to missed opportunities for improving efficiency.

“There’s rarely any ongoing verification or checking of lighting equipment efficiencies,” Sagal says. “Monitoring energy is very important.”

He stresses it’s essential to track not only overall energy use but also the energy consumed for specific strains and growth cycles. This data allows growers to assess how efficiently they’re producing each pound of cannabis.

Ideally, growers can submeter their light fixtures to get a granular view into cultivation rooms and specific zones within each chamber. Centralized powered horticultural LED lighting systems come with integrated energy-monitoring capabilities, which allow growers to track energy usage per fixture without additional hardware. These systems often provide data on energy consumption, light intensity, and operational hours via cloud-based platforms or local software.

Once a baseline power reading has been established, growers can begin experimenting with light dimming (if the systems have that capability). Growers can define light intensity settings and fine-tune them based on the needs of each strain and the environmental conditions in the grow room. This ensures growers only use the light needed to optimize plant health and productivity without wasting energy.

Sagal explains that not all light fixtures will have the same efficiency rating as they are dimmed. Fixtures with centralized power can maintain efficiency even at lower output levels. Centralized power units manage electricity for multiple lighting fixtures throughout the facility.

“They can take in a high voltage AC, essentially 480V, 3-phase, and then distribute the converted DC power to the fixtures with a much higher conversion efficiency that is higher throughout the dimming range,” Sagal says.

Optimizing the light spectrum for each cultivation stage can also reduce energy usage by only delivering the light needed at each growth stage. For example, red and far-red light is less energy-intensive to produce than blue light. Fixtures don’t necessarily require tunable spectrum capabilities. Rather, growers need “a really good spectrum,” Sagal says. “In cloning, you’re going to have much more blue and green and white, but very little red.”

As the crop matures, the lights should slowly add more red spectrum, with far-red light added later in the flowering stage. “Our testing shows that a fixed far-red spectrum at the correct ratio to deep red works extremely well, maximizing cannabinoids, yields and terpenes,” Sagal says. Recent research into far-red is yielding even more insights into its benefits and when to use it in the flowering stage.

Beyond energy-efficient fixture features, growers can stage lights, HVAC systems, and other equipment to avoid simultaneous start-ups that can significantly reduce peak demand charges. Many states calculate energy rates based on peak demand over short periods, making it essential to spread out energy-intensive activities across the day. This can lead to major cost savings, particularly in regions with high peak demand charges. “You can stage the lights and the rooms even by minutes so that you never maximize a peak demand,” Sagal says.

Additionally, many utility companies offer incentives through demand response programs, where growers can be paid (or receive a credit) to reduce energy usage during peak grid demand windows—typically when residential users draw the most power from the grid. By integrating lighting controls with these programs, growers can reduce energy costs while contributing to grid stability, making them both eco-friendly and economically savvy—another reason why data logging is important.

For growers noticing uneven growth in their crops (e.g., where lower branches have significantly less inflorescence), subcanopy lighting can be a less energy-intensive solution compared to increasing light intensity or adding more overhead fixtures.

“Intra canopy lighting allows you to get more uniform growth deeper in the canopy, resulting in bigger buds at the lower levels,” Sagal says. This approach can be especially useful in vertical farming setups common in the cannabis industry.”

Takeaways

• If you run across a cannabis opportunity, hopefully these tidbits help in designing and optimizing a system.
• Aside from cannabis, many horticulture lighting projects can benefit from the same techniques, although some refinement may be necessary.
• With more people, and businesses, operating organic farms in greenhouses as well as residential and commercial facilities (including Portland International Airport) having indoor plants, horticulture lighting could be an opportunity in your market.