Reliable heating, ventilation and air conditioning (HVAC) equipment can cost upward of $300,000 or more for a 5,000-square-foot growing facility in the cannabis space. Proper lighting might cost just as much.
But those environmental controls become less effective for an ideal harvest if they are not complemented by the intelligent application of air distribution through engineered ductwork, which isn’t overly complicated nor expensive in the grand scheme of a productive room, according to Geoff Brown, vice president of technical solutions for Quest.
Often an afterthought, airflow is currently the biggest hump for growers in relation to environmental controls, but it doesn’t have to be, Brown said. Through Quest’s partnership with Hawthorne Gardening Company, growers now have access to the Airflow Mapping service, a computer-aided analysis that calculates or predicts where a diffuser’s air will travel. In turn, growers have access to custom solutions to their specific facilities without making major changes to those facilities.
Featured here, Brown shares more about Airflow Mapping, the importance of intelligent air distribution, working with manufacturers, return on investment and other pertinent knowledge to help avoid oversights associated with environment controls.
Q: Why is airflow so important in cannabis cultivation?
A: Ultimately it just comes down to building productive plants. TIP 1 Good air circulation at the leaf is what allows the leaf to breathe, to get rid of the oxygen around the leaf and to absorb more CO2 to make sure that the transpiration is happening and that you don’t have a locally deficient vapor pressure deficit (VPD). It’s really how the system needs to work. In my opinion, airflow is the single most overlooked thing in cannabis right now, or at least it is the next hump to get over.
The hump 10 years ago was, “Oh, shoot, we’re going to put cooling units in these rooms and hopefully they’ll do enough for dehumidification.” And then there was a dehumidification problem. Now there’s a notion, “We’re putting cooling units and dehumidifiers in, so we don’t have to think about airflow.”
So, how has that been addressed? Well, people have thrown in rotation fans in the space to move air around, but there’s no real concerted effort at managing airflow, or at least thinking intelligently about how airflow works in your room. It’s an afterthought at best.
TIP 2 Proper engineered ductwork is relatively inexpensive in the grand scheme of indoor grow rooms. A 5,000-square-foot, which is a big room, and a productive room, might cost $20,000 in ductwork. And properly designed ductwork reduces the need for air-rotation fans in the space.
TIP 3 Air-rotation fans, although they’ve been used successfully, are actually a really bad thing for an efficient growth. For one, every watt they consume is an additional watt that needs to be removed from the space by a cooling system. So, you pay to run the fan and then you pay to cool off the fan. And most of those fans are also relatively inexpensive, open-pole motors. They can’t be cleaned properly between grows. So, you