Estimating latent load in a grow room
Estimating latent load in a grow room
(OP)
I am currently engineering an HVAC system for a plant growing warehouse (marijuana, in a legal state). The client wants to maintain 72 deg F at 40% RH in the grow rooms. I am trying to estimate the latent loads in one of the grow rooms (around 400 square feet) so I can ensure the system is sized correctly and I have adequate leaving air temperatures. I'm looking at using DX packaged units with digital scroll compressors and hot gas reheat, if possible. What are the best ways to estimate latent loads in this space?





RE: Estimating latent load in a grow room
RE: Estimating latent load in a grow room
RE: Estimating latent load in a grow room
RE: Estimating latent load in a grow room
RE: Estimating latent load in a grow room
Some searching led here:
https://en.wikipedia.org/wiki/Evapotranspiration
which led here:
https://en.wikipedia.org/wiki/Penman_equation
Other pages focused on the total leaf area as an important parameter:
http://passel.unl.edu/pages/informationmodule.php?...
Other important factors seem to be lighing level and air motion.
Perhaps there is something similar to this for plants:
[link Kleiber's law] https://en.wikipedia.org/wiki/Kleiber%27s_law [/link]
RE: Estimating latent load in a grow room
Transpiration of plants is directly proportional to biomass production
Maybe plant yield or growth in terms of pounds per day could be a useful parameter in estimating latent heat generation. But I don't know what constant to use if q = k * (lbm/day) is even in the ballpark. And k would seem to be a function of several variables, including: (leaf area/mass), lighting, temperature, humidity, air speed. Though those values may be relatively stable when the greenhouse is in full operation and the proportions of plants at each stage of growth are relatively constant.
You might ask whether they have any information on how much watering they do per day and the yield in mass per day. Any water that doesn't go down a drain in a steady-state operation will turn into latent heat. Perhaps their current temperature and humidity are comparable to what they want to maintain and the current watering rate will be informative.