Ensuring that the proper environmental control system is installed for indoor cannabis growing can minimize disease- and production-related issues and optimize growth.
by David Kuack
The DeltaCool Environmental System from Delta T Solutions provides indoor cannabis growers with a custom-designed package that provides precise temperature and humidity control.
Russ Zabel, general manager at Delta T Solutions in Temecula, Calif., said most indoor cannabis growers are trying to design a room to optimize growth. Zabel, who has worked with both greenhouse growers and indoor growers, said that regardless of the type of crop, whether cannabis, tomatoes or chrysanthemums, each grower produces their plants differently.
“Even though the life cycles may be different between cannabis, vegetables and ornamental plants, growers are still using a substrate and a fertilizer,” he said.
What is different is how they are producing the crops.
“Some indoor cannabis growers may produce six plants per 1,000-watt high intensity discharge (HID) light, while others will grow 10 plants per 1,000-watt light. When we design an environmental control system for cannabis production, we collect all of that information from the grower. We want to know the number of lights, the number of plants, the substrate and the method of watering. All of this information is known on the front end. This enables us to engineer an environmental control system with a bit of a buffer. A grower may say he is only going to produce eight plants per light, but we design it for nine or 10 plants to cover any production changes a grower may make.”
Even the substrate and how the plants are produced can impact the environmental control system.
“The substrates that cannabis growers are using include straight soil, rockwool and coco coir,” he said. “They are using large grow bags, different size pots and small and large rockwool slabs. That is why the environmental control system needs to be sized and designed for the specific method of production. The environment could change just by switching from coco to rockwool.”
Maintaining the proper environment
For indoor cannabis growers the biggest issue is whether they can maintain the proper environment so that they prevent disease from infecting their crops.
“Like greenhouse growers with large open greenhouses, cannabis growers using buildings with large rooms will find it more challenging to control temperature, humidity and airflow,” Zabel said. “Being able to divide the building space into moderate size rooms allows for better environmental control.
“In an indoor facility it’s a self-contained space, a closed room. Cannabis growers are recirculating the air within that space. There is no outside air coming in. The growers are incorporating carbon dioxide into the room to maintain plant growth. They are using HID lights or LED lights as a light source.”
The DeltaCool controller ensures that the equipment in the DeltaCool Environmental System delivers the cooling, heating and dehumidification necessary to maximize cannabis growth.
Not being able to maintain the proper environment can lead to issues with disease including Botrytis and powdery mildew.
“Most growers think of temperature and humidity when controlling the environment, but airflow is also a critical factor,” he said. “Having the right air velocity ensures that there is good transpiration, good carbon dioxide management and disease control.
“In order to ensure that there is adequate airflow requires the installation of more horizontal airflow (HAF) type fans. Indoor cannabis production is different than greenhouse production, so we customize a system that provides additional air movement within a space. We have been doing research with HAF fans to determine the best placement for the right air movement. It’s related to determining the proper logistics, the right fan quantity, correct placement and the appropriate velocity.
The DeltaCool controller ensures that the equipment in the DeltaCool Environmental System delivers the cooling, heating and dehumidification necessary to maximize cannabis growth.
Installing the right environmental control system
The ability to be able to maintain precise environmental control is just as important for indoor cannabis as it is for greenhouse vegetable and ornamental crops.
“It is very important to install the proper environmental control package,” Zabel said. “Our environmental control system provides both temperature and humidity control out of the same controller. Our DeltaCool system goes from chiller to fan coil control to boiler. It has everything required. It is the complete package.
“Some indoor cannabis growers may think they only need to buy a fan coil, chiller and a boiler. That’s not the case. Growers need to have all of the components and they have to work together. The proper package, including the controls, pumps, zones, fan coils, chillers and heaters, contains the equipment that works together.”
Both temperature and humidity control can be issues in indoor cannabis production.
“When the lights are on, they are generating heat, and a grower is trying to maintain 75ºF-80ºF, so there has to be cooling,” he said. “When the lights are off the plants are transpiring increasing the humidity so the environmental controls have to be able to dehumidify. Humidity control is necessary when the lights are on and off. The overall energy load is much less when the lights are off. The load for humidity control is about 30 percent of the lighting load.
“It is important to have the properly designed environmental control system for indoor cannabis production. It will turn the lights and irrigation system on and off when they’re supposed to operate. The right environmental control system will cool, heat and dehumidify. It will do all of the things necessary in an indoor grow to optimize plant growth just like in a greenhouse.”
To learn more about creating an environment with proper humidity, temperature and light levels for cannabis production, contact Delta T Solutions at [email protected] or (800) 552-5058; http://www.deltatsolutions.com. Delta T Solutions is an expert in high-efficiency heating and cooling for horticulture, cannabis and agriculture applications.
David Kuack is a freelance technical writer in Fort Worth, Texas; [email protected].