Increasing profits in greenhouses

For year-round production of high quality greenhouse crops, supplemental lighting is often necessary during periods with little sunlight. The electricity costs associated with supplemental lighting are high and may account for up to 30 percent of total production costs. UGA horticulturists developed a control system for LED grow lights that automatically responds to changing levels of sunlight. By measuring light levels at the top of the crop canopy, this controller assures that the light level never drops below a grower-defined threshold. As sunlight decreases, the LED lights automatically provide more light and vice versa. This control approach for supplemental lighting assures that the lighting is only provided when needed and only in the amount needed. This greatly reduces the cost of supplemental lighting, while assuring good growth. Initial trials have shown that this adaptive approach to controlling supplemental lighting can reduce electricity use by 60 percent with a negligible effect on crop growth. They have collaborated with PhytoSynthetix, a local grow light company, to make these adaptive lights available to the greenhouse industry.