Characterizing The Effects Of Ventilation Fans, Double Glazing, And An Automated Sidewall Roll-Up System On An Unheated High Tunnel Greenhouse In The North Carolina High Country

A high tunnel greenhouse allows agricultural producers to extend growing seasons and improve the quality of crops. High tunnel greenhouses are a viable option for agricultural producers because they are scalable, inexpensive, and easy to construct. These structures are relatively simple and require additional inputs for heating and cooling as seasonal weather variations affect the internal microclimate of the greenhouse. There are many methods for increasing a greenhouse's ability to maintain an optimal indoor microclimate. This study quantifies the individual effects of double glazing, ventilation and HAF fans, and an automated sidewall roll-up system on temperature, relative humidity levels, and light transmission in a unheated high tunnel greenhouse that is located in the North Carolina High Country. The study will also analyze the combined overall effect of five greenhouse technologies, double glazing, ventilation fans, horizontal airflow fans, an insulated ground skirt, and the automated sidewall roll-up system, working in conjunction. The study found that there was a 16.3% increase in the greenhouse's ability to maintain temperatures above 32F, and a 20% increase in the greenhouse's ability to maintain temperatures under 90F after the installation of all five systems. Frequency of freezing and overheating events in the greenhouse were reduced significantly.