Reducing lighting costs and increasing profits in greenhouses

Summary

The costs of supplemental lighting in greenhouses is second only to labor costs. We have developed a new lighting control system that automatically adapts to changing sunlight levels. This 'adaptive' lighting approach can reduce lighting costs by up to 60%.

Situation

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% of total production costs. More efficient methods to provide supplemental lighting can reduce those costs and increase the profitability of greenhouses.

Response

We 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 provide when needed and only in the amount needed. This greatly reduces the cost of supplemental lighting, while assuring good growth.

Impact

Initial trials have shown that our adaptive approach to controlling supplemental lighting can reduce electricity use by 60% with a negligible effect on crop growth. We have collaborated with PhytoSynthetix, a local grow light company, to make these adaptive lights available to the greenhouse industry.

State Issue

Agricultural Profitability and Sustainability

Details

• Year: 2016
• Geographic Scope: International
• County: Clarke
• Program Areas:
  • Agriculture & Natural Resources