“Useful Heat” and Measuring Grow Room Dehumidifier Performance

Categorised in: | 04/06/2019

Air conditioner performance looks at ”Useful Heat”. This term covers cooling, condensing duty or heat delivered by an air conditioner/heat pump. Useful heat divided by power input gives a coefficient of performance ( COP) rating for the equipment in your cannabis grow room.

If an A/C delivers 12,000 BTUs (one ton) of cooling (and condensing) and uses 1KW of power, the COP is 12,000 BTUs for each kilowatt of power consumed.
Dehumidifiers are rated by the amount of water removed, divided by power input. A rating of 240 pints per day with power requirements of 1KW, yields 10 pints per KW. If COP is calculated for dehumidifiers, “Useful Heat” to the grow room is water condensed minus excess heat added. Each hour, condensing 10 pints of water requires about 10,000 BTUs of cooling (heat of vaporization/fusion).
If 10,000 BTUs of heat is also added to the air, the net result is a COP of ZERO. For each kilowatt of power consumed, no net heat is removed from the cannabis grow room.

Our Subcooled Air 550 hybrid dehumidifier delivers cooling during lights on and on demand reheat during the lights off. This hybrid design yields a COP during lights-on of up to 15,000 BTUs per kilowatt.