The Psychometrics of Cannabis from Production through Post-Harvest: Controlling the Properties of Moist Air, Making Cannabis Affordable, Consistent, and Safe
Psychometrics is the study of moist air. What most people don't know is that there are a lot of properties of moist air. The psychometric condition of a cannabis grow room plays a large role in how plants function. It can affect the growth and final yield as well as having implications in the spread of disease, mould, and mildew. The same holds true for drying and curing as well as processing and packing.
Each of these stages require different, specific psychometric conditions which are not found in the "Comfort Cooling Zon" and not being met in the industry. VPD drives plant transpiration which drives water and nutrient usage and CO2 and O2 gas exchange, which are all vital to plant health and growth. The psychometric conditions can also promote or prevent mould, mildew, and bud rot. The current state of the industry is very energy intensive, over 50% of the energy used in cultivation goes to HVAC in an effort to control to psychometrics. Unfortunately, psychometrics and the thermodynamics needed to control them are not well understood by most HVAC designers. The problem is that large scale indorr Cannabis processing has actually never been done before, because Cannabis grows were always small and illegal. Large scale cannabis production is an industrial process, not comfort cooling, and "plants are not people".
All phases of growing require relatively high temperature and humidity, this is where the big energy savings are. Air is over cooled to condense out water, then reheated to maintain acceptable temperatures.
Drying through packaging requires much lower temperatures and humidity, this is where the real quality and consistency factor comes in. Here is where the psychometrics of the air the terpenes will either stay where they are or diffuse in the air.
Cannabis is sold by weight and the weight is determined by the psychometrics of the air. If the air is too dry it is costing money/profit. Using liquid desiccants (an adiabatic process) to directly control the moisture and sensible only cooling with a dry coil, the conditions can be precisely controlled using less than 1/2 the energy and will produce a sterile environment thus mitigating the potential for contaminatiom.