Greenhouse Ventilation is better with the Solar!
The past decade has seen an expanding use of GreenHouses not only for commercial production of food, but also as a solution in many homes and communities to food security. I hate being a pessimist but we are living in interesting times. Its not surprising that there are thousands of families and individuals around the country that want to have a year around food supply as close as their back yard. Not only does a Greehouse provide peace of mind just in case something where to hit the Fan, it also provides a steady supply of freshly grown vegetables that one can feel even more comfortable putting on the table since you know exactly what you put in the soil to grow it.
For a Greenhouse to improve food production in all environments it is necessary to have optimal Ventilation and air-flow inside. We receive calls daily here at Sunshine Works asking how to calculate the amount of air needed for a Greenhouse. Its very simple, you need to know the Cubic feet of your Greenhouse and this can be calculated by multiplying the LxWxH of your GreenHouse, as an example lets imagine we just bought a High Tunnel GH that is roughly 25ft long by 10ft Wide and 8ft Tall at the Center point, this calculation is approximate not exact but we would take all inputs and come up with (25x10x8) roughly 2k Cuft of space in the GreenHouse, pretty easy right?
Now you need to take in to consideration the kind of crop you will be planting and your humidity levels, certain crops need more ventilation than others, high air-flow crops require the air in the greenhouse to be circulated about once per minute, if this were the case with our recently purchased GreenHouse we would want to buy a 20" Snap Fan as it can easily produce the needed 2k CFM's for our Green House. This sounds pretty easy but remember this will just blow 2k CUFT in to your GreenHouse, alot of professionals like using two Fans, one to Blow and one as an exhaust generally installed closer to the ceiling of the greenhouse since Heat moves up. If we wanted that kind of arrangement with our recently purchased GreenHouse we may want to use two 16" Snap Fans, one installed facing in to the greenhouse so that it will blow between 1-1200cfm's in to your greenhouse and another close to one of the gables on the otherside pointed out so it will blow all the Hot air out of the Greenhouse and provide an optimal environment for your crop.
I hope this article helped clear out some basic questions of how to go about ventilating your Greenhouse with Solar and saving $$$ on electric bills. Please remember that during Winter Months GreenHouses typically require 30% of the ventilation required in the Winter so you will need to plan accordingly.
Also last but not least if you have a battery system available please consider checking out our 20" Super Fan. This bad boy has a Brushless Motor! The only draw back is that this motor does not do well with a wide range of Voltage so you will need to feed it directly from a battery, 12/24V. Also made here in the USA! (my favorite part)