• Energy Research

The most critical parameters of the microclimate in greenhouses are air and soil temperature, air and soil moisture, plant illumination, and carbon dioxide (CO2) concentration in photosynthesis. New energy sources and resource-efficient management of microclimate parameters in greenhouses can be utilized to reduce greenhouse crop cultivation costs and increase profits. As the plant mass increase depends on photosynthesis, which involves the formation of glucose in the plant chloroplasts from water and carbon dioxide under the influence of light radiation, the saturation of greenhouses with carbon dioxide has become popular in recent decades. However, insufficient light slows down the process of glucose formation, while excessive light intensity negatively affects photosynthesis. Based on the experimentally proven Van Henten model of plant growth and using the MATLAB environment, a methodology was proposed, and the dependence between CO2 concentration and leaf lettuce illumination power required for maximum photosynthesis was determined. It is equal to 0.57 ppm/(W/m2). Such dependence should be considered when designing control systems to reduce resource and energy costs for greenhouse crop cultivation while ensuring maximum yield.