Biological feedback control of LED grow lights

In controlled environment agricultural (CEA) systems (greenhouses and indoor plant production facilities) light is the most energy consuming, and yet the least controlled, input factor for plant growth. Plants can dissipate up to 80% of the absorbed light energy as heat through physiological protective mechanisms (non photochemical quenching) and this light cannot be used for plant growth. Light energy consumption represents up to 30% of the final cost of the produce. While all other inputs are monitored and controlled based on plant needs, light control is rudimentary (on/off).Knowing the fate of the light that is absorbed by the leaves makes it possible to monitor changes in photosynthetic parameters, and allows for automated changes in lighting based on the physiology of the plants. PhytoSynthetix and the University of Georgia have developed a biological feedback system that monitors how efficiently the plants are using the light for photosynthesis. The system uses this information to optimize energy use efficiency based on the plants physiological performance. The light output from the LED lights can be adjusted based upon the plant's physiology (photosynthetic efficiency). Based on the plants' requirements, the system autonomously adjusts the LED grow lights duty-cycle to match plants requirements reducing the system energy consumption.The primary project goal is improve CEA by reducing the costs associated with artificial lighting, thus promoting energy conservation. Our research represent the next step in the LED grow lighting development. Our technology is unique and complements previous research which has largely focused on LED spectra and light intensity. This project will add a new dimension to the use of LED lighting in CEA. It will yield the first lighting system controlled by plants, increasing energy use efficiency and reducing energy consumption.Our approach involves first testing the already developed biological feedback system to validate our preliminary data. Next, we will improve the capabilities of the system to expend the applications and achieve optimal energy use efficiency. Finally, we will reduce the cost of the system by replacing the most expensive part, the commercial chlorophyll fluorometer. A new, low-cost sensor will be developed to provide the data needed to run the biofeedback system.The electricity savings our technology can offer for CEA will be an important contribution to energy use reduction and food production, and be will be cost effective. At the same time, the reduced energy use will lower CO2 emissions and thus contribute to climate change mitigation. It will bring benefits to CEA growers, reducing their energy consumption and making them more competitive. This will increase the economic feasibility and sustainability of CEA.