Greenhouse evaporative cooling, Humidity, and Salinity


Premium Member
Mr. Calfo,
Have you found a say "Saturation point" in using evaporative cooling up to a certain % level of humidity to where evaporative cooling becomes ineffecient. To my understanding alot of it has to do with the temperature of the water used to do the evaporative cooling also this added moisture will most likely affect salinity levels, if so any "magic formula" :rolleyes: for calculating that as well? I leave my fans on now when its raining and in essence I would say that is using evap. cooling because it brings the moist air into the GH, this also I have found out has seized one of my fans up :mad2: Im thinking the best indication point that Evaporative cooling is innefecient is basically when condensation on the side of the glass which usually occurs over 55% humidity levels and as it gets higher it gets more ineffective. Does this sound right, if not how off base am I? Thanx ya!

Anthony Calfo

New member
you are on the right track fer' sure. I do recall reading data on the efficacy of evaporative cooling at increasing humidity. Our friend Denis Lebrun recently shared some links to pages/reports on data he dug up regarding the same topic.

I'll go look for what I have and ask/suggest you give Denis a jingle for his data too.

Many other-industry GH folks in humid regions like your have resorted to using desicating agents (often cheap-o calcium chloride road salt... mere dollars per ton) on trays in front of the mechanized shutters to dry the incoming air so that it is better able to assist with evaporative cooling as your exhaust fan on the other side pulls it across the pools.

Many interesting possibilities.

My advice is to move :D Tampa is way too humid. Ha!